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Sample records for agglutination test stat

  1. Direct agglutination test for serologic diagnosis of Neospora caninum infection.

    PubMed

    Romand, S; Thulliez, P; Dubey, J P

    1998-01-01

    A direct agglutination test was evaluated for the detection and quantitation of IgG antibodies to Neospora caninum in both experimental and natural infections in various animal species. As compared with results obtained by the indirect fluorescent antibody test, the direct agglutination test appeared reliable for the serologic diagnosis of neosporosis in a variety of animal species. The direct agglutination test should provide easily available and inexpensive tools for serologic testing for antibodies to N. caninum in many host species. PMID:9491426

  2. Latex agglutination tests for measurement of antiplague antibodies.

    PubMed Central

    Suzuki, S; Sakakibara, H; Hotta, S

    1977-01-01

    A latex agglutination test was evaluated as a method for detection and titration of antiplague antibodies. Slide and microtiter techniques using polystyrene latex particles coated with specific fraction-I-antigen of Yersinia pestis were found to be comparable in specificity and sensitivity to serological tests commonly used in laboratory practice. The latex agglutination titers correlated well with those measured by the World Health Organization standard method of indirect hemagglutination, although there was a tendency for the former to be a little lower than the latter. With further study, the latex agglutination test may have application in the seroinvestigation of plague infection in rodents. Images PMID:914990

  3. Simple solutions to false results with plate/slide agglutination tests in diagnosis of infectious diseases of man and animals.

    PubMed

    Saxena, Hari Mohan; Chothe, Shubhada; Kaur, Paviter

    2015-01-01

    We have developed a new Superagglutination test for serodiagnosis of infectious diseases. It differs from conventional plate/slide agglutination tests (PAT/SAT) by three additional steps: prior staining of serum antibody by adding a dye and addition of diluted biotinylated antiglobulin and avidin in sequence after mixing the antigen with the test serum. The new steps circumvent the problems of false positive and false negative results of PAT/SAT. In serodiagnosis of brucellosis, Superagglutination test had higher positive predictive value and specificity than Rose Bengal Plate Test (RBPT) and Standard Tube Agglutination Test (STAT) and higher negative predictive value and sensitivity than RBPT, STAT, ELISA and Complement Fixation Test (CFT).•Superagglutination is a simple, accurate and economic screening test for infections.•More specificity, sensitivity, positive & negative predictive value than RBPT, STAT.•More sensitivity, negative predictive value than ELISA and Complement Fixation Test. PMID:26844209

  4. Simple solutions to false results with plate/slide agglutination tests in diagnosis of infectious diseases of man and animals

    PubMed Central

    Saxena, Hari Mohan; Chothe, Shubhada; Kaur, Paviter

    2015-01-01

    We have developed a new Superagglutination test for serodiagnosis of infectious diseases. It differs from conventional plate/slide agglutination tests (PAT/SAT) by three additional steps: prior staining of serum antibody by adding a dye and addition of diluted biotinylated antiglobulin and avidin in sequence after mixing the antigen with the test serum. The new steps circumvent the problems of false positive and false negative results of PAT/SAT. In serodiagnosis of brucellosis, Superagglutination test had higher positive predictive value and specificity than Rose Bengal Plate Test (RBPT) and Standard Tube Agglutination Test (STAT) and higher negative predictive value and sensitivity than RBPT, STAT, ELISA and Complement Fixation Test (CFT).•Superagglutination is a simple, accurate and economic screening test for infections.•More specificity, sensitivity, positive & negative predictive value than RBPT, STAT.•More sensitivity, negative predictive value than ELISA and Complement Fixation Test. PMID:26844209

  5. Latex agglutination test (LAT) for the diagnosis of typhoid fever.

    PubMed

    Sahni, Gopal Shankar

    2013-06-01

    The efficacy of latex agglutination test in the rapid diagnosis of typhoid fever was studied and the result compared with that of blood culture. This study included 80 children suffering from typhoid fever, among which 40 were confirmed by blood culture isolation and 40 had possible typhoid fever based on high Widal's titre (a four-fold rise in the titre of antibody to typhi "O" and "H" antigen was considered as a positive Widal's test result). Eighty children, 40 with febrile illness confirmed to be other than typhoid and 40 normal healthy children were used as negative controls. The various groups were: (i) Study group ie, group I had 40 children confirmed by culture isolation of Salmonella typhi(confirmed typhoid cases). (ii) Control groups ie, (a) group II with 40 febrile controls selected from paediatrics ward where cause other than S typhi has been established, (b) group III with 40 afebrile healthy controls that were siblings of the children admitted in paediatric ward for any reason with no history of fever and TAB vaccination in the last one year, and (c) group IV with 40 children with high Widal's titre in paired sera sample. Widal's test with paired sera with a one week interval between collections were done in all 40 patients. Latex aggtutination test which could detect 900 ng/ml of antigen as observed in checker board titration, was positive in all 40 children from group I who had positive blood culture and in 30 children from group IV who had culture negative and had high Widal's titre positive. Latex agglutination test was positive in 4 children in group II and none in group III. Using blood culture positive cases as true positive and children in groups II and III as true negative, the test had a sensitivity of 100% and specificity of 96%. Latex agglutination test was found to be significantly sensitive (100%) and specific (96%) and could detect 75% more cases in group IV (possible typhoid cases). Thus latex agglutination test can be used for rapid

  6. Macroscopic Agglutination Test for Rapid Diagnosis of Human Leptospirosis

    PubMed Central

    Brandão, Angela P.; Camargo, Eide D.; da Silva, Emilson D.; Silva, Marcos V.; Abrão, Rui V.

    1998-01-01

    A commercially available slide agglutination test (SAT) for the diagnosis of human leptospirosis was evaluated by comparing it to an immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) and to the microscopic agglutination test (MAT). For all 108 patients, leptospirosis was diagnosed on the basis of a fourfold or greater increase in titer by MAT (seroconversion), and all but 1 of 245 controls were MAT negative (titers, <1:100). Both SAT and the IgM ELISA failed to detect one case of infection (sensitivity, 99%). Only 3 of 145 blood donors and none of the 100 patients with other illnesses were SAT positive (specificity, 99%). The overall results were similar for the three tests; however, SAT and ELISA were statistically more sensitive as initial screening tests. For 22% of the patients, the diagnosis of leptospirosis was made earlier by SAT than by MAT. SAT detected 27 (44%) of 62 MAT-negative patients with the first serum sample. ELISA and SAT had very similar results. Follow-up of patients for 1 year after the onset of symptoms showed a decreasing rate of positivity by SAT from the third month on. The rate of positivity by ELISA decreased more slowly, to about 67% by the end of the study. By MAT all patients were persistently reactive. SAT and ELISA seem to be convenient methods for the rapid and early screening for leptospirosis and could replace the less sensitive MAT. ELISA gives less subjective results than SAT and provides information on IgM kinetics, but it can be performed only by the more sophisticated laboratories. SAT is inexpensive, can be performed more quickly and more easily than ELISA, and could be used by the less well equipped laboratories. PMID:9774553

  7. A comparison of titers of anti-Brucella antibodies of naturally infected and healthy vaccinated cattle by standard tube agglutination test, microtiter plate agglutination test, indirect hemagglutination assay, and indirect enzyme-linked immunosorbent assay

    PubMed Central

    Mohan, Anju; Saxena, Hari Mohan; Malhotra, Puneet

    2016-01-01

    Aim: We determined the antibody response in cattle naturally infected with brucellosis and normal healthy adult cattle vaccinated during calf hood with strain 19. Materials and Methods: The antibody titers were measured by standard tube agglutination test (STAT), microtiter plate agglutination test (MAT), indirect hemagglutination assay (IHA), and indirect enzyme-linked immunosorbent assay (iELISA) as per standard protocols. Results: The mean STAT titers were 1.963±0.345 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was extremely significant (p<0.0001). The mean MAT titers were 2.244±0.727 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was very significant (p<0.005). The mean IHA titers in infected cattle were 2.284±0.574, and those in healthy vaccinated cattle were 1.200±0.155. The difference was extremely significant (p=0.0002). However, the difference in mean iELISA titers of infected cattle (1.3678±0.014) and healthy vaccinated cattle (1.367±0.014) was non-significant. The infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals. However, it cannot be ascertained whether these antibodies are due to vaccine or response to infection. Since the infected animals had been vaccinated earlier, the current infection may suggest that vaccination was unable to induce protective levels of antibody. The heightened antibody response after infection may also indicate a secondary immune response to the antigens common to the vaccine strain and wild Brucella organisms. Conclusion: The brucellosis infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals. PMID:27536032

  8. Evaluation of the one-point microcapsule agglutination test for diagnosis of leptospirosis.

    PubMed Central

    Arimitsu, Y.; Kmety, E.; Ananyina, Y.; Baranton, G.; Ferguson, I. R.; Smythe, L.; Terpstra, W. J.

    1994-01-01

    We have developed a one-point microcapsule agglutination test (MCAT) for the serodiagnosis of leptospirosis. The MCAT kit was evaluated for use in humans by six WHO Collaborating Centres for Reference and Research on Leptospirosis. The laboratories classified their serum samples on the basis of the microscopic agglutination test (MAT) and the following screening tests: enzyme-linked immunosorbent assay (ELISA), macroscopic (slide) agglutination test, or the complement fixation test. The MCAT may in some instances give a positive result earlier in the course of the disease than MAT or the ELISA IgM; on the other hand, it did not detect antibodies against some serovars, for example, those of the Sejroe or Australis serogroup in Slovakia. In contrast, however, the MCAT detected antibodies to serovar hardjo (the same serogroup as Sejroe) in patients from the United Kingdom and the Russian Federation. PMID:8062397

  9. Human African trypanosomiasis: a latex agglutination field test for quantifying IgM in cerebrospinal fluid.

    PubMed Central

    Lejon, V.; Büscher, P.; Sema, N. H.; Magnus, E.; Van Meirvenne, N.

    1998-01-01

    LATEX/IgM, a rapid agglutination test for the semi-quantitative detection of IgM in cerebrospinal fluid of patients with African trypanosomiasis, is described in this article. The lyophilized reagent has been designed for field use and remains stable at 45 degrees C for one year. The test has been evaluated on cerebrospinal fluid samples from trypanosome-infected and non-infected patients, by comparison with commercial latex agglutination, radial immunodiffusion, and nephelometry. All test systems yielded similar results. PMID:10191550

  10. Comparative evaluation of recombinant LigB protein and heat-killed antigen-based latex agglutination test with microscopic agglutination test for diagnosis of bovine leptospirosis.

    PubMed

    Nagalingam, Mohandoss; Thirumalesh, Sushma Rahim Assadi; Kalleshamurthy, Triveni; Niharika, Nakkala; Balamurugan, Vinayagamurthy; Shome, Rajeswari; Sengupta, Pinaki Prasad; Shome, Bibek Ranjan; Prabhudas, Krishnamsetty; Rahman, Habibur

    2015-10-01

    This study aimed to develop latex agglutination test (LAT) using recombinant leptospiral immunoglobulin-like protein (LigB) (rLigB) antigen and compare its diagnostic efficacy with LAT using conventional heat-killed leptospiral antigen and microscopic agglutination test (MAT) in diagnosing bovine leptospirosis. The PCR-amplified 1053-bp ligB gene sequences from Leptospira borgpetersenii Hardjo serovar were cloned in pET 32 (a) vector at EcoRI and NotI sites and expressed in BL21 E. coli cells as fusion protein with thioredoxin (-57 kDa) and characterized by SDS-PAGE and immunoblot. Out of 390 serum samples [cattle (n = 214), buffaloes (n = 176)] subjected to MAT, 115 samples showed reciprocal titre≥100 up to 1600 against one or more serovars. For recombinant LigB protein/antigen-based LAT, agglutination was observed in the positive sample, while no agglutination was observed in the negative sample. Similarly, heat-killed leptospiral antigen was prepared from and used in LAT for comparison with MAT. A two-sided contingency table was used for analysis of LAT using both the antigens separately against MAT for 390 serum samples. The sensitivity, specificity and positive and negative predictive values of recombinant LigB LAT were found to be 75.65, 91.27, 78.38 and 89.96 %, respectively, and that of heat-killed antigen-based LAT were 72.17, 89.82, 74.77 and 88.53 %, respectively, in comparison with MAT. This developed test will be an alternative/complementary to the existing battery of diagnostic assays/tests for specific detection of pathogenic Leptospira infection in bovine population. PMID:26065562

  11. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT AUXILIARY PROVISIONS ON NATIONAL POULTRY IMPROVEMENT PLAN Blood Testing Procedures § 147.1 The standard...

  12. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a... to December 2, 1932, pp. 487 to 491. (a) The blood samples should be collected and delivered as follows: (1) The blood samples should be taken by properly qualified and authorized persons only, and...

  13. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a... to December 2, 1932, pp. 487 to 491. (a) The blood samples should be collected and delivered as follows: (1) The blood samples should be taken by properly qualified and authorized persons only, and...

  14. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a... to December 2, 1932, pp. 487 to 491. (a) The blood samples should be collected and delivered as follows: (1) The blood samples should be taken by properly qualified and authorized persons only, and...

  15. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a... to December 2, 1932, pp. 487 to 491. (a) The blood samples should be collected and delivered as follows: (1) The blood samples should be taken by properly qualified and authorized persons only, and...

  16. Development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus.

    PubMed

    Trinh, Dai Quang; Ogawa, Haruko; Bui, Vuong Nghia; Nguyen, Tham Thi Hong; Gronsang, Dulyatad; Baatartsogt, Tugsbaatar; Kizito, Mugimba Kahoza; AboElkhair, Mohammed; Yamaguchi, Shigeo; Nguyen, Viet Khong; Imai, Kunitoshi

    2015-09-01

    A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value=0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology. PMID:25952731

  17. Salmonella typhi VI antigen co-agglutination test for the rapid diagnosis of typhoid fever.

    PubMed

    Rao, P S; Prasad, S V; Arunkumar, G; Shivananda, P G

    1999-01-01

    A slide Co-agglutination test for the detection of Salmonella typhi Vi antigen in blood was evaluated for its efficiency in rapid diagnosis of Typhoid fever. The results were compared with conventional methods like Blood culture and Widal test. The test showed a sensitivity of 86.67% and specificity of 88.83% when compared with blood culture positivity or Widal titre above 160. This is a useful rapid diagnostic test for the early diagnosis of Typhoid fever. PMID:10798017

  18. A microtitration agglutination test for detecting group E streptococcus infection in swine.

    PubMed

    Armstrong, C H; Wood, R L; Wessman, G E

    1982-04-01

    A microtitration agglutination test was developed and evaluated for detecting infection of swine with group E streptococci type IV, the most common causative agent of streptococcic lymphadenitis of swine. Whole cell agglutinogens representing group and type antigens of group E streptococci were tested in the microtitration agglutination test against reference antisera to Streptococcus groups A, B, C, D, E, F, G. H, K, L, M, N, O, P, Q, R, S and U, as well as specific antisera to types II, IV and V of group E. Group E specific agglutinogens were unsatisfactory in the microtitration agglutination test because of cross reactions with group P and U antisera and because of poor reproducibility of the test. Type specific agglutinogens of group E streptococci reacted only with their respective homologous antisera and not with any heterologous group antisera. None of the group E streptococci agglutinogens reacted with 52 normal swine sera. Agglutinogen made from group E streptococci type IV was selected for further evaluation in the microtitration agglutination test because group E streptococci types II and V are considered to be of minor importance in the etiology of streptococcic lymphadenitis of swine. Swine experimentally infected with a type IV strain developed significant titers in the microtitration agglutination test. All swine tested negative before exposure and seroconverted (titer >/=4) two to six weeks postexposure.The microtitration agglutination test was used by two different laboratories to test 187 duplicate samples of serum from infected swine. A total of 94.1% of the tests were read at either the same titer (48.1%) or a difference of not more than one dilution (46.0%) at the two laboratories. There was disagreement between the two laboratories in the test-positive test-negative status of 19 of the sera (10.2%). Titers of two of the sera differed by two dilutions (<4 at one laboratory and 8 at the other). The remaining 17 sera differed in titer by only one

  19. A Microtitration Agglutination Test for Detecting Group E Streptococcus Infection in Swine

    PubMed Central

    Armstrong, C.H.; Wood, R.L.; Wessman, G.E.

    1982-01-01

    A microtitration agglutination test was developed and evaluated for detecting infection of swine with group E streptococci type IV, the most common causative agent of streptococcic lymphadenitis of swine. Whole cell agglutinogens representing group and type antigens of group E streptococci were tested in the microtitration agglutination test against reference antisera to Streptococcus groups A, B, C, D, E, F, G. H, K, L, M, N, O, P, Q, R, S and U, as well as specific antisera to types II, IV and V of group E. Group E specific agglutinogens were unsatisfactory in the microtitration agglutination test because of cross reactions with group P and U antisera and because of poor reproducibility of the test. Type specific agglutinogens of group E streptococci reacted only with their respective homologous antisera and not with any heterologous group antisera. None of the group E streptococci agglutinogens reacted with 52 normal swine sera. Agglutinogen made from group E streptococci type IV was selected for further evaluation in the microtitration agglutination test because group E streptococci types II and V are considered to be of minor importance in the etiology of streptococcic lymphadenitis of swine. Swine experimentally infected with a type IV strain developed significant titers in the microtitration agglutination test. All swine tested negative before exposure and seroconverted (titer ≥4) two to six weeks postexposure. The microtitration agglutination test was used by two different laboratories to test 187 duplicate samples of serum from infected swine. A total of 94.1% of the tests were read at either the same titer (48.1%) or a difference of not more than one dilution (46.0%) at the two laboratories. There was disagreement between the two laboratories in the test-positive test-negative status of 19 of the sera (10.2%). Titers of two of the sera differed by two dilutions (<4 at one laboratory and 8 at the other). The remaining 17 sera differed in titer by only

  20. A monoclonal antibody-based latex bead agglutination test for the detection of Bordetella avium.

    PubMed

    Suresh, P; Arp, L H

    1993-01-01

    The purpose of this study was to develop a rapid method to distinguish Bordetella avium from closely related Bordetella avium-like and B. bronchiseptica bacteria. A monoclonal antibody of the IgM isotype was produced in Balb/c mice against live B. avium strain 75. The monoclonal antibody, in the form of ascites fluid, was added to a bovine serum albumin-glycine buffer (pH 8.6) and adsorbed to 3.03-microns-diameter latex beads. Optimum concentrations of antibody, beads, and bacteria were determined. The latex bead conjugate was tested against 40 isolates of B. avium, 24 isolates of B. avium-like bacteria, 17 isolates of B. bronchiseptica, two isolates of Alcaligenes faecalis, and several other common genera. Strong agglutination occurred with all B. avium isolates and the two isolates of A. faecalis. Weak agglutination occurred with Staphylococcus aureus and two isolates of B. bronchiseptica. There was no agglutination with any of the B. avium-like isolates. The latex bead agglutination test may be useful as an aid in the identification of B. avium when used in conjunction with other criteria. PMID:8257369

  1. Field evaluation of latex agglutination test for detecting urinary antigens in visceral leishmaniasis in Sudan.

    PubMed

    El-Safi, S H; Abdel-Haleem, A; Hammad, A; El-Basha, I; Omer, A; Kareem, H G; Boelaert, M; Chance, M; Hommel, M

    2003-07-01

    A latex agglutination test to detect urinary antigens for visceral leishmaniasis (VL) was studied. In 204 patients with suspected VL, KAtex had a sensitivity of 95.2% with good agreement with microscopy smears but poor agreement with 4 different serology tests. It was also positive in 2 confirmed VL cases co-infected with HIV. In all K4tex-positive confirmed cases actively followed up after treatment, the test became negative 1 month after completion of treatment. While IC4tex had a specificity of 100% in healthy endemic and non-endemic controls, the direct agglutination test (DAT) was positive in 14% of the KAtex-negative healthy endemic controls. KAtex is a simple addition to the diagnostics of VL particularly at field level and as a complementary test for the diagnosis of VL in smear-negative cases with positive DAT results. PMID:15748081

  2. Use of latex agglutination test to determine rabies antibodies in production of rabies antisera in horses.

    PubMed

    Saengseesom, Wachiraporn; Kasempimolporn, Songsri; Akesowan, Surasak; Ouisuwan, Suraseha; Sitprija, Visith

    2010-11-01

    A therapeutic anti-rabies immunoglobulin for human use has been produced mainly in horses. The presently available seroneutralization test, the rapid fluorescent focus inhibition test (RFFIT), is laborious and rather difficult to carry out in horse farms. This study was undertaken to develop a simple latex agglutination test (LAT) for determining rabies antibodies in horse sera. LAT was validated by testing a total of 468 horse serum samples characterized by RFFIT. Of these, 253 of 260 samples with antibody titers of less than 100 IU/ml had agglutination score of 1+, whereas 174 of 208 samples with antibody titers equal to or greater than 100 IU/ml had agglutination scores of 2-4+. Results of LAT correlated with those of RFFIT (r = 0.87, p < 0.0001). LAT has the advantages of being rapid, simple to perform, easy to interpret, and applicable as an on-site testing tool for the estimation of rabies antibodies in horses. PMID:21329315

  3. Elemental X-ray mapping of agglutinated foraminifer tests: a non- destructive technique for determining compositional characteristics.

    USGS Publications Warehouse

    Commeau, R.F.; Reynolds, Leslie A.; Poag, C.W.

    1985-01-01

    The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers. -Authors

  4. Microscopic agglutination test on captive rattlesnakes : Data on serovars and titers.

    PubMed

    Rodrigues, T C S; Santos, A L Q; Lima, A M C; Gomes, D O; Cardoso, G F; Brites, V L C

    2016-06-01

    The microscopic agglutination test (MAT) is considered the "golden standard" leptospirosis serodiagnostic test, but there is little information about it as it pertains to snakes. To fill this information gap, we provide data on serovars and titers of fifty-six Crotalus durissus collilineatus sera samples that tested positive by MAT (10.1016/j.actatropica.2016.02.006 (Rodrigues et al., 2016) [5]). These data are presented in a table, along with a description of the methodology used for sample collection and serologic testing. PMID:27077089

  5. Microscopic agglutination test on captive rattlesnakes : Data on serovars and titers

    PubMed Central

    Rodrigues, T.C.S.; Santos, A.L.Q.; Lima, A.M.C.; Gomes, D.O.; Cardoso, G.F.; Brites, V.L.C.

    2016-01-01

    The microscopic agglutination test (MAT) is considered the “golden standard” leptospirosis serodiagnostic test, but there is little information about it as it pertains to snakes. To fill this information gap, we provide data on serovars and titers of fifty-six Crotalus durissus collilineatus sera samples that tested positive by MAT (10.1016/j.actatropica.2016.02.006 (Rodrigues et al., 2016) [5]). These data are presented in a table, along with a description of the methodology used for sample collection and serologic testing. PMID:27077089

  6. Latex agglutination test based on single-chain Fv recombinant antibody fragment.

    PubMed

    Golchin, M; Khalili-Yazdi, A; Karamouzian, M; Abareghi, A

    2012-01-01

    Recombinant antibodies have been proposed as invaluable tools for various therapeutic and diagnostic purposes. Here, we describe the development of a novel latex agglutination test (LAT) using single-chain Fv recombinant antibody fragment for the detection of K99(+) enterotoxigenic Escherichia coli strains. For the production of a single-chain Fv antibody fragment (scFv) against the major colonization factor (FanC) of K99 antigen, the scFv gene was integrated into a bacterial expression vector under the control of T7 promoter. After high-level expression of soluble scFv (approximately 50 mg/l) in flask cultivation of E. coli DE3 and purification, scFv was immobilized on different latex particles, and then, these sensitized beads were used in LAT. Results obtained with our latex reagents revealed that the recombinant antibody-coated particles were able to give a good agglutination signal with purified antigen, intact cells displaying this protein and clinical specimens. The strength of agglutination of scFv-coated beads for antigen was comparable to that of polyclonal anti-K99-coated particles. However, the assay proved to be simple and rapid, similar to conventional LATs, and owing to more convenient and economical production of recombinant antibodies, they can be considered as a useful reagent for replacing monoclonal antibodies in LATs. PMID:21916915

  7. Diagnostic value of latex agglutination test in diagnosis of acute bacterial meningitis

    PubMed Central

    Mohammadi, Syeda Fasiha; Patil, Asha B.; Nadagir, Shobha D.; Nandihal, Namrata; Lakshminarayana, S. A.

    2013-01-01

    Objectives: To know the incidence of bacterial meningitis in children below five years of age. To compare conventional culture and antigen detection methods (Latex agglutination test). Materials and Methods: 100 CSF samples of clinically suspected meningitis cases in children below 5 years of age were included. The samples were subjected to cell count, Gram stain, culture and LAT. The organisms isolated in the study were characterized according to standard procedures. Results: Of the 100 cases studied, 31 cases were diagnosed as ABM by Gram stain, culture and latex agglutination test as per WHO criteria. The hospital frequency of ABM was 1.7%. 15 (48.38) cases were culture positive. Gram stain was positive in 22(70.96) cases and LAT in 17(54.83) cases. Haemophilus influenzae was the most common causative agent of acute bacterial meningitis followed by S.pneumoniae. Case fatality rate was 45.16%. The sensitivity and specificity of LAT was 66.66% and 87.91% respectively. Conclusion: Bacterial meningitis is a medical emergency and early diagnosis and treatment is life saving and reduces chronic morbidity. LAT was more sensitive compared to conventional Gram stain and Culture technique in identifying the fastidious organisms like H.influenzae, S.pneumoniae and Group B Streptococcus. However, the combination of Gram stain, Culture and LAT proved to be more productive than any of the single tests alone. PMID:24339598

  8. Agglutinated tests in post-Sturtian cap carbonates of Namibia and Mongolia

    NASA Astrophysics Data System (ADS)

    Bosak, T.; Lahr, D. J. G.; Pruss, S. B.; Macdonald, F. A.; Dalton, L.; Matys, E.

    2011-08-01

    Paleomagnetic data suggest that the early Cryogenian (Sturtian) glaciation extended to sea level at low latitude. The impact of this dramatic environmental change on biota, and the composition of ecosystems in the immediate aftermath of the Sturtian glaciation remain virtually unknown. Here we report the discovery of abundant agglutinated tests in organic-rich carbonates directly overlying Sturtian glacial deposits from two different paleocontinents: the Rasthof Formation of the Congo craton in northern Namibia and the Tsagaan Oloom Formation of the Dzabkhan terrane in Mongolia. The most abundant tests preserve morphological and compositional characters consistent with those found in at least two different families of modern lobose testate amoebae (Amoebozoa), a group of heterotrophic microbial eukaryotes. The presence of spatially and compositionally variable clay minerals, quartz and microcline on the test walls is a signature of widespread biological agglutination. The post-glacial fossil assemblages differ from the most common pre-Sturtian vase-shaped fossil testate amoebae, perhaps as a result of different preservational mechanisms or of the appearance of new forms after the glaciation. The apparent local abundance of eukaryotic body fossils in the post-Sturtian carbonates suggests that the Cryogenian limestones and dolostones may host a currently unexplored fossil record of modern eukaryotes.

  9. Development of a Latex Agglutination Test as a Simple and Rapid Method for Diagnosis of Trichomonas vaginalis Infection.

    PubMed

    Darani, Hossein Yousofi; Ahmadi, Firuzeh; Zabardast, Nozhat; Yousefi, Hossein Ali; Shirzad, Hedayat

    2010-01-01

    Trichomoniasis is a worldwide infection and due to its complications rapid and accurate diagnosis of infection especially in pregnant women is very important. In this study, development of a latex agglutination test using native antigens for rapid diagnosis of trichomoniasis is investigated. Trichomonas vaginalis was harvested from TYIS33 culture medium and anti Trichomonas vaginalis antiserum was raised in rabbits. Salt precipitation method was used for antibody purification. Polyesteren latex particles coated with purified antibody and used for detection of Trichomonas vaginalis. Clinical samples of vaginal discharge were collected from 500 women and examined for Trichomonas vaginalis by using wet mount, culture and latex agglutination tests. Sensitivity and specificity of latex test was determined considering culture as golden standard. Sensitivity and specificity of latex agglutination test was 100% and 81% and those of wet mount were 33.3% and 100%, respectively. Positive and negative predictive values of latex agglutination test were 6% and 100%, respectively. Due to inconvenient sensitivity and specificity of the latex agglutination test developed in this study, further work is recommended to improve the test. PMID:23408769

  10. Antibodies and the Aberdeen typhoid outbreak of 1964. II. Coombs', complement fixation and fimbrial agglutination tests.

    PubMed

    Brodie, J

    1977-10-01

    In a previous paper (Brodie, 1977) the value of the Widal test in the diagnosis of typhoid fever was shown to be limited. Evaluation of possible alternative tests showed that: (1) the sensitivity of the anti-human globulin (Coombs') test appeared greater than that of the agglutination test but the length of time (48 h) before results were available rendered it of little value in rapid diagnosis: (2) the complement fixation test offered no particular help towards diagnosis; (3) immunized and non-immunized typhoid fever patients developed fimbrial antibodies, as also did immunized healthy individuals. In this latter group, however, those immunized with alcoholized TAB vaccine had higher antibody titres to fimbrial antigen than those immunized with heat-killed phenolized vaccine. PMID:269194

  11. The relationship of the lunar regolith less than 10-microns fraction and agglutinates. II - Chemical composition of agglutinate glass as a test of the 'fusion of the finest fraction' /F3/ model

    NASA Technical Reports Server (NTRS)

    Walker, R. J.; Papike, J. J.

    1982-01-01

    Agglutinate glasses from nine Apollo soils have been studied using an automated electron microprobe technique in order to test the fusion of the finest fraction model proposed by Papike (1981). The nine average agglutinate glass compositions are compared with the calculated fused-soil-free compositions, the bulk compositions and the 90-20 micron fraction compositions of the soils in which they are found. It is found that the agglutinate glass data are consistent with the composition of most of the fractions finer than 10 microns, allowing for the volatile loss of K2O and Na2O; some inconsistencies that do arise may result from the degree of soil maturity and the amount of material finer than 10 microns. It is concluded that the fusion of the finest fraction model is a good first approximation of mechanisms affecting the formation of agglutinate glass.

  12. Seroprevalence of bovine leptospiral antibodies by microscopic agglutination test in Southeast of Iran

    PubMed Central

    Khalili, Mohammad; Sakhaee, Ehsanollah; Aflatoonian, Mohammad Reza; Abdollahpour, Gholamreza; Tabrizi, Saeed Sattari; Damaneh, Elham Mohammadi; Hossini-nasab, Sajad

    2014-01-01

    Objective To evaluate serological findings of bovine leptospirosis which is a zoonotic disease with worldwide distribution caused by Leptospira interrogans. Methods One hundred and sixty seven sera were collected from 9 commercial dairy herds in jiroft suburbs, from July to October 2011. Microscopic agglutination test (MAT) was used to evaluates serological findings of bovine leptospirosis in Jiroft suburb dairy farms, Kerman province, Iran. Results Antibodies were found by MAT at least against one serovar of Leptospira interrogans in 29 samples (17.36%) among 167 sera at a dilution 1:100 or higher, and Leptospira pomona was the most prevalent serovar. Positive titers against more than one serovar were detected in 6 sera of the positive samples. Conclusion This study is the first report of leptospirosis in Southeast Iran and showed that Leptospira pomona was the most and Leptospira icterohaemorrhagiae the least prevalent serovars in Southeast Iran. PMID:25182718

  13. Development of a Specific Latex Agglutination Test to Detect Antibodies of Enterovirus 71.

    PubMed

    Qin, Bo; Zhang, Jianhua; Xie, Wenhao; Liu, Xuehong; He, Tingting; Chen, Jinkun; Dong, Xuejun

    2015-10-01

    A latex agglutination test (LAT) was developed for the rapid detection of antibodies against the VP1 or VP1 proteins of Enterovirus 71 (EV71). The proteins of interest including prokaryotically expressed VP1 and two strains of anti-VP1 monoclonal antibody (McAb) against EV71 were covalently linked to carboxylated latex using ethyl-dimethyl-amino-propyl carbodiimide (EDC) to prepare sensitized latex beads. LAT was evaluated by an enzyme-linked immunosorbent assay (ELISA) as a reference test. The VP1-LAT showed a sensitivity of 87.0%, specificity of 88.9%, and an agreement ratio of 90.0% in detecting VP1 in 100 serum samples from experimentally infected mice, whereas these values were 86.8, 96.7, and 93.3%, respectively, for 608 clinical human serum samples. The VP1-LAT has advantages over other assays in terms of low cost, rapidity, chemical stability, high sensitivity, repeatability, and specificity. The LAT established in the present study is a rapid and simple test suitable for field monitoring of antibodies against VP1-EV71. PMID:26363276

  14. A systematic review on the microscopic agglutination test seroepidemiology of bovine leptospirosis in Latin America.

    PubMed

    Pinto, Priscila da Silva; Libonati, Hugo; Penna, Bruno; Lilenbaum, Walter

    2016-02-01

    The diagnosis of leptospirosis commonly relies on serology, which has three issues that are referred: the sampling, the antigen panel, and the cutoff point. We propose a systematic review of the bovine leptospirosis in Latin America, in order to provide a better understanding of the evolution of the research and of the seroepidemiology of bovine leptospirosis in that region. Internet databases were consulted over the year of 2014. Inclusion criteria for analysis included serosurvey using microscopic agglutination test (MAT), a relevant number of animals, the presence in the antigen panel of at least one representant of serogroup Sejroe, and a cutoff point of ≥100. A total of 242 articles that referred to cattle, leptospir*, and one region of Latin America was found. Only 105 articles regarding to serosurveys using MAT were found in several countries, and 61 (58.1 %) met all the inclusion criteria. In conclusion, this systematic review demonstrated a high prevalence of the infection (75.0 % at herd level and 44.2 % at animal level), with predominance of strains of serogroup Sejroe (80.3 %). It was evident that there is the necessity of more studies in several countries, as well as the need for greater standardization in studies, especially with regard to the adopted cutoff point at serological tests. PMID:26581437

  15. [Activity of porcine anti-Brucella abortus immunoglobulins in the acid plate agglutination test (APAT)].

    PubMed

    Stryszak, A; Błaszczyk, B; Królak, M

    1987-01-01

    Serological activity of swine IgM and IgG against Brucella abortus in RBPT was determined in relation to four other reactions used in Poland for diagnosing brucellosis standard agglutination test, complement fixation test, antiglobulin test, 2-mercaptoethanol test). Isolation of IgG was performed by the method of filtration on Sephadex gel G-200 of swine sera raised against Brucella abortus S19 by double immunization with suspension of killed bacteria. The presence of a certain Ig class in the fractions thus obtained was confirmed by immunoelectrophoresis and immunodiffusion tests. RBPT revealed the reaction of antibodies of IgM and IgG class which proves usability of this reaction diagnosis both early (IgM) and chronic (IgG) infection with brucellosis. Both classes of antibodies mentioned above were active also in SAT and CTT. Also the results obtained in AGT and MET were found interesting. In one of the sera, the absence of incomplete antibodies was observed, whereas positive reaction in antiglobulin test was found in its fractions containing IgG. This phenomenon was determined as concealment of incomplete agglutinins through higher level of complete antibodies in normal serum. In swine (the results were different from those obtained for cattle), apart from incomplete antibodies in IgG class, the presence of these agglutinins in IgM class was noted. On the other hand, the results obtained in MET proved that IgM antibodies of swine were not totally reduced when affected by 2-mercaptoethanol. PMID:3137534

  16. Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis

    PubMed Central

    Enabulele, Osahon; Awunor, Simeon Nyemike

    2016-01-01

    Background: Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients. Materials and Methods: Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever. Results: Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection. Conclusion: A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test. PMID:27397952

  17. Occurrence of leptospiral infections in swine population in Poland evaluated by ELISA and microscopic agglutination test.

    PubMed

    Wasiński, B; Pejsak, Z

    2010-01-01

    Swine are one of significant reservoirs and sources of Leptospira infections for man. Serological screenings help to effectively control the epidemiological situation in swine herds and to prevent transmission of Leptospira from animals to man. The purpose of this study was to investigate, by the use of serological methods, the prevalence of infections caused by selected Leptospira serogroups in swine population in Poland. A total of 7112 swine serum samples were examined. The samples were collected from January to October 2008 and came from 280 counties situated in all 16 provinces of Poland. All sera were examined preliminary by enzyme-linked immunosorbent assay (ELISA) using heat-stable antigenic preparation. The samples positive or doubtful in ELISA were investigated by microscopic agglutination test (MAT) with use of serovars Icterohaemorrhagiae, Pomona, Canicola, Sejroe, Tarassovi and Of the collected sera examined by ELISA 73 (1.02%) samples were positive, 85 (1.20%)--doubtful and 6954--negative. Among ELISA-positive and doubtful sera 64 samples (coming from 14 provinces) were recognized in MAT as positive. Among MAT positive samples 42.19% of sera demonstrated titres with serovar Pomona, 32.81%--with Sejroe, 14.06%--with Icterohaemorrhagiae, 6.25%--with Tarassovi, 3.13%--with Grippotyphosa and 1.56% with Canicola. PMID:21370749

  18. Seroprevalence of Mycoplasma gallisepticum antibody by ELISA and serum plate agglutination test of laying chicken

    PubMed Central

    Ali, Md. Zulfekar; Rahman, Md. Mostafizer; Sultana, Shirin

    2015-01-01

    Aim: Mycoplasma gallisepticum (MG) is important avian pathogens responsible for chronic respiratory diseases of chicken and turkeys, which result in large economic loss for the poultry industry. The objectives of this study were determination of seroprevalence of MG antibody of commercial layer chicken at laying period in selected areas of Bangladesh. Materials and Methods: A total of 563 blood samples were collected randomly from selected commercial layer chickens at laying period during the period from July to December, 2013. Indirect enzyme linked immunosorbent assay (iELISA) and serum plate agglutination (SPA) test were performed to detect the presence of antibodies against MG. Results: Of 563 samples, 64.47% and 56.13% showed an overall prevalence of MG antibodies in iELISA and SPA test respectively. Prevalence of MG was recorded the highest (69.63%) at 50-55 weeks of age compared with lowest (53.26%) at 56-61 weeks of age (p<0.05). Significant (p<0.05) effect of breed were observed in the seroprevalence of MG infection in layer birds in the present study. The overall, 68.77%, 63.74% and 59.37% prevalence were found respectively in sonali, ISA Brown and White leg horn. The prevalence of MG antibodies was the highest (70.13%) in December followed by November (68%), October (65.67%), August (63.46%), September (58.54%) and July (51.78%) month. The seroprevalence of MG antibodies was higher (69.63%) in most of the large flocks and lower (56.82%) in small flocks. Conclusion: Therefore, might be suggested that the commercial layer farms should be routinely checked to monitor MG infection and the reactor birds should be culled since MG organism has the potential to transmit vertically. The correlation between MG antibody in month and flock size was not significant (p=0.359 and p=0.868, respectively). PMID:27046987

  19. A meta-analysis of the diagnostic performance of the direct agglutination test and rK39 dipstick for visceral leishmaniasis

    PubMed Central

    Chappuis, François; Rijal, Suman; Soto, Alonso; Menten, Joris; Boelaert, Marleen

    2006-01-01

    Objective To compare the performance of the direct agglutination test and rK39 dipstick for the diagnosis of visceral leishmaniasis. Data sources Medline, citation tracking, January 1986 to December 2004. Selection criteria Original studies evaluating the direct agglutination test or the rK39 dipstick with clinical visceral leishmaniasis as target condition; adequate reference classification; and absolute numbers of true positive, true negative, false positive, and false negative observations available or derivable from the data presented. Results 30 studies evaluating the direct agglutination test and 13 studies evaluating the rK39 dipstick met the inclusion criteria. The combined sensitivity estimates of the direct agglutination test and the rK39 dipstick were 94.8% (95% confidence interval 92.7% to 96.4%) and 93.9% (87.7% to 97.1%), respectively. Sensitivity seemed higher and more homogenous in the studies carried out in South Asia. Specificity estimates were influenced by the type of controls. In phase III studies carried out on patients with clinically suspected disease, the estimated specificity of the direct agglutination test was 85.9% (72.3% to 93.4%) and of the rK39 dipstick was 90.6% (66.8% to 97.9%). Conclusion The diagnostic performance of the direct agglutination test and the rK39 dipstick for visceral leishmaniasis is good to excellent and seem comparable. PMID:16882683

  20. Performance of commercial latex agglutination tests for the differentiation of Candida dubliniensis and Candida albicans in routine diagnostics.

    PubMed

    Chryssanthou, E; Fernandez, V; Petrini, B

    2007-11-01

    Candida dubliniensis is phenotypically similar to Candida albicans and may therefore be underdiagnosed in the clinical microbiology laboratory. The performance of Bichro-Dubli latex agglutination test for rapid species identification of C. dubliniensis was prospectively evaluated on 111 vaginal and 118 respiratory isolates. These had presumptively been identified as C. albicans/C. dubliniensis by their green colonies on CHROMagar Candida plates. Bichro-Dubli test identifed 2 (1.8%) vaginal and 6 (5.1%) respiratory isolates as C. dubliniensis. The test was also positive for 37 C. dubliniensis control strains characterised by 18S-28S DNA-sequencing. Bichro-Dubli test is thus a sensitive and accurate tool for rapid diagnostics in routine laboratories. PMID:18092961

  1. A prototype of the direct agglutination test kit (DAT-Canis) for the serological diagnosis of canine visceral leishmaniasis.

    PubMed

    Oliveira, Edward; Saliba, Juliana Wilke; Oliveira, Diana; Dias, Edelberto Santos; Paz, Gustavo Fontes

    2016-05-15

    This report describes the stege I/II development of a new direct agglutination test (DAT) for the diagnosis of canine visceral leishmaniasis (CVL) using freeze-dried antigen produced Coomassie blue-stained Leishmania (Leishmania) infantum promastigotes. In stage I, 16 canine serum samples, collected from eight dogs carrying CVL and eight healthy dogs, were assessed with the DAT using 2-mercaptoethanol (2-ME), N-acetyl-cysteine (NAC), kaolin or NAC plus urea (NAC+U) to improve the assay conditions. Stage II assessed the diagnostic accuracy with 100 serum samples collected from dogs with symptomatic CVL and clinically healthy dogs, comparing the four different sample diluents. The CVL-DAT prototype kit showed equivalent performances when 2-ME, NAC or NAC+U were used: 97.1% sensitivity (CI: 83-99.8%), 97% specificity (CI: 88.5-99.5%) and a 97% diagnostic accuracy (CI: 90.8-99.2). With kaolin, a 94.1% sensitivity (CI: 79-99%), 97% specificity (CI: 88.5-99.5%) and 96% diagnostic accuracy were observed (CI: 89.5-98.7), with no statistically significant differences among the four reagents (p=1.0). The NAC plus urea in sample diluent decreased non-specific agglutination, promoted a better defined sharp-edged blue spot and was thus chosen as a component for the new DAT prototype to diagnose canine VL, designated DAT-Canis. PMID:27084465

  2. Sensitivity and Specificity of an Improved Rapid Latex Agglutination Test for Identification of Methicillin-Sensitive and -Resistant Staphylococcus aureus Isolates

    PubMed Central

    Smole, Sandra C.; Aronson, Elyssa; Durbin, Annette; Brecher, Stephen M.; Arbeit, Robert D.

    1998-01-01

    The performance of a second-generation rapid agglutination kit, Slidex Staph Plus (SSP; bioMérieux), was compared to those of the Slidex Staph (SS; bioMérieux), Staphaurex (SRX; Murex Diagnostics), and BBL Staphyloslide (BBL; Becton Dickinson) kits by using 508 clinical isolates composed of 150 methicillin-sensitive Staphylococcus aureus (MSSA) organisms, 154 methicillin-resistant S. aureus (MRSA) organisms, and 204 non-S. aureus Staphylococcus spp. Of the 508 isolates tested, 75% were fresh clinical isolates, with the remainder taken from five different freezer collections. All four agglutination tests had comparable sensitivities for MSSA and MRSA. However, the SS kit was significantly less specific (93.1%) than the three other tests (P > 0.05, McNemar test). These results demonstrate that the new rapid latex agglutination kit, SSP, was more specific for the identification of S. aureus than the previous version and performed comparably to the SRX and BBL kits. PMID:9542948

  3. Diagnosis of Leptospirosis: Comparison between Microscopic Agglutination Test, IgM-ELISA and IgM Rapid Immunochromatography Test

    PubMed Central

    Niloofa, Roshan; Fernando, Narmada; de Silva, Nipun Lakshitha; Karunanayake, Lilani; Wickramasinghe, Hasith; Dikmadugoda, Nandana; Premawansa, Gayani; Wickramasinghe, Rajitha; de Silva, H. Janaka; Premawansa, Sunil; Rajapakse, Senaka; Handunnetti, Shiroma

    2015-01-01

    Background Leptospirosis is diagnosed on clinical grounds, and confirmed by microscopic agglutination test (MAT). IgM-ELISA (Serion-Virion) and immunochromatography test (Leptocheck-WB) are two immunodiagnostic assays for leptospirosis. Their sensitivity, specificity and applicability in Sri Lanka have not been systematically evaluated. Methods Clinically diagnosed leptospirosis patients (n = 919) were recruited from three hospitals in the Western Province of Sri Lanka, during June 2012 to December 2013. MAT, IgM-ELISA and Leptocheck-WB were performed on all patient sera. MAT titer of ≥400 in single sample, four-fold rise or seroconversion ≥100 in paired samples were considered as positive for MAT. For diagnostic confirmation, MAT was performed during both acute and convalescent phases. Anti-leptospiral IgM ≥20 IU/ml and appearance of a band in the test window were considered as positive for IgM-ELISA and Leptocheck-WB test respectively. Patients with an alternative diagnosis (n = 31) were excluded. Data analysis was performed using two methods, i) considering MAT as reference standard and ii) using Bayesian latent class model analysis (BLCM) which considers each test as imperfect. Results MAT, IgM-ELISA and Leptocheck-WB positivity were 39.8%, 45.8% and 38.7% respectively during the acute phase. Acute-phase MAT had specificity and sensitivity of 95.7% and 55.3% respectively, when compared to overall MAT positivity. IgM-ELISA and Leptocheck-WB had similar diagnostic sensitivity when compared with acute-phase MAT as the gold standard, although IgM-ELISA showed higher specificity (84.5%) than Leptocheck-WB (73.3%). BLCM analysis showed that IgM-ELISA and Leptocheck-WB had similar sensitivities (86.0% and 87.4%), while acute-phase MAT had the lowest sensitivity (77.4%). However, acute-phase MAT had high specificity (97.6%), while IgM-ELISA and Leptocheck-WB showed similar but lower specificity (84.5% and 82.9%). Conclusions Both IgM-ELISA and Leptocheck-WB shows

  4. Bayesian estimation of sensitivity and specificity of the modified agglutination test and bioassay for detection of Toxoplasma gondii in free-range chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxoplasma gondii infects virtually all warm-blooded animals worldwide. Serological tests, including the modified agglutination test (MAT), are often used to determine exposure to the parasite. The MAT can be used for all hosts because it does not need species-specific reagents and has been shown to...

  5. A modified agglutination test for Neospora caninum: development, optimization, and comparison to the indirect fluorescent-antibody test and enzyme-linked immunosorbent assay.

    PubMed

    Packham, A E; Sverlow, K W; Conrad, P A; Loomis, E F; Rowe, J D; Anderson, M L; Marsh, A E; Cray, C; Barr, B C

    1998-07-01

    Current serologic tests used to detect antibodies to Neospora caninum require species-specific secondary antibodies, limiting the number of species that can be tested. In order to examine a wide variety of animal species that may be infected with N. caninum, a modified direct agglutination test (N-MAT) similar to the Toxoplasma gondii modified direct agglutination test (T-MAT) was developed. This test measures the direct agglutination of parasites by N. caninum-specific antibodies in serum, thus eliminating the need for secondary host-specific anti-isotype sera. The N-MAT was compared to the indirect fluorescent-antibody test (IFAT) and the enzyme-linked immunosorbent assay (ELISA) with a "gold standard" serum panel from species for which secondary antibodies were available (n = 547). All positive samples tested were from animals with histologically confirmed infections. Up to 16 different species were tested. The N-MAT gave a higher sensitivity (100%) and specificity (97%) than the ELISA (74 and 94%, respectively) and had a higher sensitivity but a lower specificity than the IFAT (98 and 99%, respectively). The reduced specificity of the N-MAT was due to false-positive reactions in testing fetal fluids with particulate matter or severely hemolyzed serum. Overall, the N-MAT proved to be highly sensitive and specific for both naturally and experimentally infected animals, highly reproducible between and within readers, easy to use on large sample sizes without requiring special equipment, and useful in testing serum from any species without modification. PMID:9665950

  6. A Modified Agglutination Test for Neospora caninum: Development, Optimization, and Comparison to the Indirect Fluorescent-Antibody Test and Enzyme-Linked Immunosorbent Assay

    PubMed Central

    Packham, Andrea E.; Sverlow, Karen W.; Conrad, Patricia A.; Loomis, Emily F.; Rowe, Joan D.; Anderson, Mark L.; Marsh, Antoinette E.; Cray, Carolyn; Barr, Bradd C.

    1998-01-01

    Current serologic tests used to detect antibodies to Neospora caninum require species-specific secondary antibodies, limiting the number of species that can be tested. In order to examine a wide variety of animal species that may be infected with N. caninum, a modified direct agglutination test (N-MAT) similar to the Toxoplasma gondii modified direct agglutination test (T-MAT) was developed. This test measures the direct agglutination of parasites by N. caninum-specific antibodies in serum, thus eliminating the need for secondary host-specific anti-isotype sera. The N-MAT was compared to the indirect fluorescent-antibody test (IFAT) and the enzyme-linked immunosorbent assay (ELISA) with a “gold standard” serum panel from species for which secondary antibodies were available (n = 547). All positive samples tested were from animals with histologically confirmed infections. Up to 16 different species were tested. The N-MAT gave a higher sensitivity (100%) and specificity (97%) than the ELISA (74 and 94%, respectively) and had a higher sensitivity but a lower specificity than the IFAT (98 and 99%, respectively). The reduced specificity of the N-MAT was due to false-positive reactions in testing fetal fluids with particulate matter or severely hemolyzed serum. Overall, the N-MAT proved to be highly sensitive and specific for both naturally and experimentally infected animals, highly reproducible between and within readers, easy to use on large sample sizes without requiring special equipment, and useful in testing serum from any species without modification. PMID:9665950

  7. Reverse-Transcriptase PCR Detection of Leptospira: Absence of Agreement with Single-Specimen Microscopic Agglutination Testing

    PubMed Central

    Waggoner, Jesse J.; Balassiano, Ilana; Mohamed-Hadley, Alisha; Vital-Brazil, Juliana Magalhães; Sahoo, Malaya K.; Pinsky, Benjamin A.

    2015-01-01

    Background Reference diagnostic tests for leptospirosis include nucleic acid amplification tests, bacterial culture, and microscopic agglutination testing (MAT) of acute and convalescent serum. However, clinical laboratories often do not receive paired specimens. In the current study, we tested serum samples using a highly sensitive real-time nucleic acid amplification test for Leptospira and compared results to MAT performed on the same specimens. Methods/Principal Findings 478 serum samples from suspected leptospirosis cases in Rio de Janeiro were tested using a real-time RT-PCR for the diagnosis of leptospirosis, malaria and dengue (the Lepto-MD assay). The Lepto-MD assay detects all species of Leptospira (saprophytic, intermediate, and pathogenic), and in the current study, we demonstrate that this assay amplifies both Leptospira RNA and DNA. Dengue virus RNA was identified in 10 patients, and no cases of malaria were detected. A total of 65 samples (13.6%) were positive for Leptospira: 35 samples (7.3%) in the Lepto-MD assay, 33 samples (6.9%) by MAT, and 3 samples tested positive by both (kappa statistic 0.02). Poor agreement between methods was consistent regardless of the titer used to define positive MAT results or the day of disease at sample collection. Leptospira nucleic acids were detected in the Lepto-MD assay as late as day 22, and cycle threshold values did not differ based on the day of disease. When Lepto-MD assay results were added to the MAT results for all patients in 2008 (n=818), the number of detected leptospirosis cases increased by 30.4%, from 102 (12.5%) to 133 (16.3%). Conclusions/Significance This study demonstrates a lack of agreement between nucleic acid detection of Leptospira and single-specimen MAT, which may result from the clearance of bacteremia coinciding with the appearance of agglutinating antibodies. A combined testing strategy for acute leptospirosis, including molecular and serologic testing, appears necessary to maximize

  8. Local Production of a Liquid Direct Agglutination Test as a Sustainable Measure for Control of Visceral Leishmaniasis in Sudan.

    PubMed

    Osman, Hussam Ali; Mahamoud, Abdelhafeiz; Abass, Elfadil Mustafa; Madi, Rubens Riscala; Semiao-Santos, Saul J; El Harith, Abdallah

    2016-05-01

    A prerequisite for the control of visceral leishmaniasis (VL) is the accessibility to reference diagnostics. The high price of the freeze-dried direct agglutination test (FD-DAT) and the short shelf-life time of the rK39 strip test (rK39) have limited the application of these tests in Sudan. An original liquid DAT (LQ-DAT) with high reproducibility compared with the FD-DAT and rK39 has been routinely produced in our laboratory since 1999. In this study, a 3.4-year-old batch (of more than 90 test batches produced to date) was chosen to validate the diagnostic performance of this test against microscopy, FD-DAT, and rK39 in 96 VL and 42 non-VL serum samples. Relatively higher sensitivity (95/96, 99.0%) was recorded for the LQ-DAT than for the FD-DAT (92/96, 95.8%) and rK39 (76/96, 79.2%), probably because of the use of the endemic autochthonous Leishmania donovani isolate as the antigen. Experience with the LQ-DAT, its low cost of production, ease of providing this test, and diagnostic reliability compared with the FD-DAT suggest that widescale implementation of the LQ-DAT can contribute to sustainable VL control in Sudan. PMID:26976890

  9. Development and Evaluation of a Rapid Latex Agglutination Test Using a Monoclonal Antibody To Identify Candida dubliniensis Colonies

    PubMed Central

    Marot-Leblond, Agnes; Beucher, Bertrand; David, Sandrine; Nail-Billaud, Sandrine; Robert, Raymond

    2006-01-01

    Cell components of the dimorphic pathogenic fungus Candida dubliniensis were used to prepare monoclonal antibodies (MAbs). One MAb, designated 12F7-F2, was shown by indirect immunofluorescence to be specific for a surface antigen of Candida dubliniensis yeast cells. No reactivity was observed with other fungal genera or with other Candida species, including Candida albicans, that share many phenotypic features with C. dubliniensis. The use of different chemical and physical treatments for cell component extraction suggested that the specific epitope probably resides on a protein moiety absent from C. albicans. However, we failed to identify the target protein by Western blotting, owing to its sensitivity to heat and sodium dodecyl sulfate. MAb 12F7-F2 was further used to develop a commercial latex agglutination test to identify C. dubliniensis colonies (Bichro-dubli Fumouze test; Fumouze Diagnostics). The test was validated on yeast strains previously identified by PCR and on fresh clinical isolates; these included 46 C. dubliniensis isolates, 45 C. albicans isolates, and other yeast species. The test had 100% sensitivity and specificity for C. dubliniensis isolated on Sabouraud dextrose, CHROMagar Candida, and CandiSelect media and 97.8% sensitivity for C. dubliniensis grown on Candida ID medium. The test is rapid (5 min) and easy to use and may be recommended for routine use in clinical microbiology laboratories and for epidemiological investigations. PMID:16390961

  10. Development and evaluation of a rapid latex agglutination test using a monoclonal antibody to identify Candida dubliniensis colonies.

    PubMed

    Marot-Leblond, Agnes; Beucher, Bertrand; David, Sandrine; Nail-Billaud, Sandrine; Robert, Raymond

    2006-01-01

    Cell components of the dimorphic pathogenic fungus Candida dubliniensis were used to prepare monoclonal antibodies (MAbs). One MAb, designated 12F7-F2, was shown by indirect immunofluorescence to be specific for a surface antigen of Candida dubliniensis yeast cells. No reactivity was observed with other fungal genera or with other Candida species, including Candida albicans, that share many phenotypic features with C. dubliniensis. The use of different chemical and physical treatments for cell component extraction suggested that the specific epitope probably resides on a protein moiety absent from C. albicans. However, we failed to identify the target protein by Western blotting, owing to its sensitivity to heat and sodium dodecyl sulfate. MAb 12F7-F2 was further used to develop a commercial latex agglutination test to identify C. dubliniensis colonies (Bichro-dubli Fumouze test; Fumouze Diagnostics). The test was validated on yeast strains previously identified by PCR and on fresh clinical isolates; these included 46 C. dubliniensis isolates, 45 C. albicans isolates, and other yeast species. The test had 100% sensitivity and specificity for C. dubliniensis isolated on Sabouraud dextrose, CHROMagar Candida, and CandiSelect media and 97.8% sensitivity for C. dubliniensis grown on Candida ID medium. The test is rapid (5 min) and easy to use and may be recommended for routine use in clinical microbiology laboratories and for epidemiological investigations. PMID:16390961

  11. Rapid detection of methicillin resistance in Staphylococcus aureus isolates by the MRSA-screen latex agglutination test.

    PubMed

    van Leeuwen, W B; van Pelt, C; Luijendijk, A; Verbrugh, H A; Goessens, W H

    1999-09-01

    The slide agglutination test MRSA-Screen (Denka Seiken Co., Niigata, Japan) was compared with the mecA PCR ("gold standard") for the detection of methicillin resistance in Staphylococcus aureus. The MRSA-Screen test detected the penicillin-binding protein 2a (PBP2a) antigen in 87 of 90 genetically diverse methicillin-resistant S. aureus (MRSA) stock culture strains, leading to a sensitivity of 97%. The three discrepant MRSA strains displayed positive results only after induction of the mecA gene by exposure to methicillin. Both mecA PCR and MRSA-Screen displayed negative results among the methicillin-susceptible S. aureus strains (n = 106), as well as for Micrococcus spp. (n = 10), members of the family Enterobacteriaceae (n = 10), Streptococcus pneumoniae (n = 10), and Enterococcus spp. (n = 10) (specificity = 100%). Producing the same PBP2a antigen, all 10 methicillin-resistant Staphylococcus epidermidis strains score positived in both the latex test and the mecA PCR. Consequently, the MRSA-Screen test should be applied only after identification of the MRSA strain to the species level to rule out coagulase-negative staphylococci. In conclusion, due to excellent specificity and sensitivity the MRSA-Screen latex test has the potential to be successfully used for routine applications in the microbiology laboratory. PMID:10449498

  12. Detection of leishmanial antigen in the urine of patients with visceral leishmaniasis by a latex agglutination test.

    PubMed

    Sundar, Shyam; Agrawal, Shrinkhla; Pai, Kalpana; Chance, Michael; Hommel, Marcel

    2005-08-01

    Diagnosis of visceral leishmaniasis (VL) is usually done by demonstration of parasites in tissue smears. However, obtaining these smears may be risky, painful, and difficult. Antibody-based diagnostics are limited by their inability to predict active disease. In this study, a new latex agglutination test (KAtex), which detects parasite antigen in freshly voided and boiled urine, was evaluated in patients with VL before the start (n = 382) and at the end of treatment (n = 273); 185 healthy controls from leishmaniasis-endemic region were also studied. The KAtex result was positive in 87% (95% confidence interval [CI] = 83.3-90.3). However, at the end of treatment only 3% (95% CI = 1.6-6.2) patients were positive. The specificity of the test was 99% and 2 of 185 healthy controls tested positive. Positive and negative predictive values were 0.994 and 0.788, respectively. KAtex is a promising test, and in a simplified and improved format it could be applied meaningfully in the diagnosis of VL. PMID:16103587

  13. Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis.

    PubMed

    Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

    2016-09-01

    Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. PMID:27207442

  14. Detection of enterotoxigenic Clostridium perfringens in food and fecal samples with a duplex PCR and the slide latex agglutination test.

    PubMed Central

    Fach, P; Popoff, M R

    1997-01-01

    A duplex PCR procedure was evaluated for the detection of Clostridium perfringens in food and biological samples and for the identification of enterotoxigenic strains. This method uses two sets of primers which amplify in the same reaction two different DNA fragments simultaneously: the 283-bp C. perfringens phospholipase C gene fragment and the 426-bp enterotoxin gene fragment. Internal primers within the two primer sets confirmed the specificity of the method by DNA-DNA hybridization with the PCR products. No cross-reaction was observed with other Clostridium species or with other bacteria routinely found in food. The detection level was approximately 10(5) C. perfringens cells per g of stool or food sample. When overnight enrichment culture was used, 10 C. perfringens cells per g was detected in 57 artificially contaminated food samples. The duplex PCR is a rapid, sensitive, and reliable method for the detection and identification of enterotoxigenic C. perfringens strains in food samples. A slide latex agglutination test was also evaluated as a rapid, simple technique for the detection of C. perfringens enterotoxin in stool samples. PMID:9361409

  15. A novel agglutination test for antigen-specific detection of platelet antibodies.

    PubMed

    Meyer, Oliver; Agaylan, Ashraf; Borchert, Hans-Hubert; Aslan, Tunay; Bombard, Stéphane; Kiesewetter, Holger; Salama, Abdulgabar

    2006-10-15

    A simple and rapid antigen-specific assay for the identification antibodies to platelets is lacking, yet. Red-dyed polystyrene microbeads were coated with monoclonal antibodies to various platelet glycoprotein complexes, and used for the detection of platelet autoantibodies and alloantibodies. The results were largely identical with those obtained by monoclonal antibody-specific immobilization of platelet antigen assay (MAIPA). The new test is reliable yet less complex and time-consuming than the currently available assays, and it can be implemented in any routine laboratory. PMID:16933262

  16. Prevalence of Candida albicans and Trichomonas vaginalis in pregnant women in Havana City by an immunologic latex agglutination test.

    PubMed

    Fernández Limia, Octavio; Lantero, María Isela; Betancourt, Arsenio; de Armas, Elizabeth; Villoch, Alejandra

    2004-10-15

    We aimed to estimate the prevalence of Candida albicans and Trichomonas vaginalis in immunocompetent pregnant women living in Havana City, Cuba, with or without symptoms of vaginitis, using a sample of 640 women from 6 Gyneco-obstetrics hospitals, which represents 2.5% of total yearly pregnant women. Diagnosis was made using a new latex agglutination kit (Newvagin C-Kure, La Habana, Cuba). Clinical sensitivity and specificity of this assay were validated against culture method, with 467 and 489 clinical specimens for Candida albicans and Trichomonas vaginalis, respectively. Results showed that the kit clinical sensitivity was 100% for Candida albicans and 86.7% for Trichomonas vaginalis compared with a clinical specificity of 93.3% for Candida albicans and 95.1% for Trichomonas vaginalis by culture. The prevalence of candidiasis was determined to be 42.3% (95% confidence interval [CI] 3.8%); the prevalence of trichomoniasis was 9.84% (95% CI 2.3%). In our sample, 48.7% of the women tested negative with respect to both candidiasis and trichomoniasis. Only 6.41% of the cases yielded inconclusive results. The test has high sensitivity, and our results indicate a relatively high prevalence of both infections. However, a significant difference (P < .001) was also observed in candidiasis and trichomoniasis prevalence among hospitals corresponding to the quantity of women with clinical vaginitis. No difference was observed between diabetics and nondiabetics, probably due to the special care of diabetic pregnant women. We conclude that the method is useful for this kind of vaginitis prevalence study and that candidiasis and trichomoniasis prevalences in pregnant women of Havana are 38.5% to 46.2 % (95% CI) and 7.5% to 12.1% (95% CI), respectively. PMID:15775877

  17. Rapid Detection of Methicillin Resistance in Coagulase-Negative Staphylococci by a Penicillin-Binding Protein 2a-Specific Latex Agglutination Test

    PubMed Central

    Horstkotte, Matthias A.; Knobloch, Johannes K.-M.; Rohde, Holger; Mack, Dietrich

    2001-01-01

    The detection of PBP 2a by the MRSA-Screen latex agglutination test with 201 clinical coagulase-negative staphylococci had an initial sensitivity of 98% and a high degree of specificity for Staphylococcus epidermidis strains compared to PCR for mecA. Determination of oxacillin MICs evaluated according to the new breakpoint (0.5 μg/ml) of the National Committee for Clinical Laboratory Standards exhibited an extremely low specificity for this population. PMID:11574595

  18. Latex agglutination test

    MedlinePlus

    ... laboratory method to check for certain antibodies or antigens in a variety of body fluids including saliva, ... latex beads coated with a specific antibody or antigen. If the suspected substance is present, the latex ...

  19. Agglutination of Helicobacter pylori coccoids by lectins

    PubMed Central

    Khin, Mar Mar; Hua, Jie Song; Ng, Han Cong; Wadström, Torkel; Ho, Bow

    2000-01-01

    AIM: To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms. METHODS: Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS: Strong agglutination was observed with mannose-specific Concanavalin A (Con A), fucose-specific Tetragonolobus purpureas (Lotus A) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori lectin agglutination. Interes tingly, heating of H. pylori cells at 60 °C for 1 h was shown to augment the agglutination with all of the lectins tested. CONCLUSION: The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during the events of morphological transformation, resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection. This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease. PMID:11819557

  20. Multi-centric prospective evaluation of rk39 rapid test and direct agglutination test for the diagnosis of visceral leishmaniasis in Brazil.

    PubMed

    de Assis, Tália S M; Braga, Alexandre S da C; Pedras, Mariana J; Oliveira, Edward; Barral, Aldina; de Siqueira, Isadora C; Costa, Carlos H N; Costa, Dorcas L; Holanda, Thiago A; Soares, Vítor Y R; Biá, Mauro; Caldas, Arlene de J M; Romero, Gustavo A S; Rabello, Ana

    2011-02-01

    The diagnosis of visceral leishmaniasis (VL) is still a major problem in Brazil and several other countries where the disease is endemic. The use of an easy-to-use and interpret, sensitive, and specific method that requires no complex infrastructure or specialized professionals, such as direct agglutination test (DAT) and the rK39-based rapid immunochromatographic test may enhance the diagnosis of disease. This study evaluated the performance of a rapid test (DiaMed- IT-LEISH®) and the DAT for the diagnosis of VL in 213 parasitologically confirmed cases and 119 controls with clinical suspicion of VL and confirmation of another etiology. The sensitivities and specificities of the rapid test were 93% and 97%, respectively and those of the DAT were 90% and 96%, respectively. The positive predictive values of the rapid test and the DAT were 98% and 97%, respectively and the negative predictive values were 89% and 84%, respectively. The Kappa index showed agreement between both methods classified as substantial (0.77). This study showed that the DAT and the rapid test can be used to diagnose VL in Brazil, following a pilot study for implementation of the rapid test in the health services. PMID:20970152

  1. TrypTect CIATT--a card indirect agglutination trypanosomiasis test for diagnosis of Trypanosoma brucei gambiense and T. b. rhodesiense infections.

    PubMed

    Nantulya, V M

    1997-01-01

    A simple and rapid test, the card indirect agglutination trypanosomiasis test (TrypTect CIATT) is described, for detecting circulating antigens in persons suffering from Trypanosoma brucei gambiense and T. b. rhodesiense infection by latex agglutination. The sensitivity of the test (95.8% for T. b. gambiense and 97.7% for T. b. rhodesiense) was significantly higher than that of lymph node puncture, microhaematocrit centrifugation and cerebrospinal fluid examination after single and double centrifugation. The specificity of the test was also high: 106 blood donor sera as well as sera from 37 patients with malaria, 25 with visceral leishmaniasis, 10 with schistosomiasis, 5 with filariasis and 10 with hydatid disease, from trypanosomiasis-free areas, gave negative results. Eighteen clinical suspects from active disease transmission foci, without microscopically detectable parasitaemia but with a positive test result, were further examined by lumbar puncture and inoculation of blood into mice; 11 (61%) were found to be infected, suggesting that the test had a high positive predictive value. This study showed that TrypTect CIATT is a useful test for rapid diagnosis of both patent and non-patent T. b. gambiense and T. b. rhodesiense infections. PMID:9463665

  2. Serological evidence of Leishmania donovani infection in apparently healthy dogs using direct agglutination test (DAT) and rk39 dipstick tests in Kafta Humera, north-west Ethiopia.

    PubMed

    Kalayou, S; Tadelle, H; Bsrat, A; Abebe, N; Haileselassie, M; Schallig, H D F H

    2011-06-01

    Leishmania (Kinetoplastida: Trypanosomatidae) are protozoan parasites of significant medical and veterinary importance. Over the last decade, visceral leishmaniasis (VL) has emerged as a major opportunistic infection associated with HIV/AIDS in North Western Ethiopia. This paper reports on serological evidence of possible Leishmania donovani (L. donovani) infection in dogs using two serological tests: direct agglutination test (DAT) and Kalazar detect rapid test (KDRT). Two hundred and seventeen asymptomatic local breed dogs were examined for L. donovani antibodies. Performance of the DAT and KDRT was assessed in 162 matching samples of blood collected on filter paper and serum, respectively. Using DAT and KDRT testing in parallel, the overall seroprevalence of L. donovani infection was 27.7% and 14.8%, respectively. The degree of agreement was found to be fair (68.8%, k = 0.234). Univariable logistic regression analysis of some risk factors for L. donovani infection in dogs using DAT indicates that place of residence, sex, age, dog keeping purpose and dog housing condition were not significantly associated with seropositivity. The high proportion of positive dogs suggests the exposure of these animals to L. donovani infection and needs further investigation. Isolation and typing of the parasite aiming at confirming the role of these animals in maintenance and transmission of kala-azar is advocated. PMID:21371289

  3. Comparison of passive haemagglutination test with Widal agglutination test for serological diagnosis of typhoid fever in an endemic area.

    PubMed

    Coovadia, Y M; Singh, V; Bhana, R H; Moodley, N

    1986-06-01

    A passive haemagglutination test, using sheep red blood cells sensitised with Salmonella typhi lipopolysaccharide, was compared with the Widal test for the serological diagnosis of typhoid fever in an endemic area. The results obtained on sera from 152 patients with bacteriologically confirmed typhoid and 183 patients who did not have typhoid were analysed in terms of sensitivity, specificity, simplicity, and rapidity of the respective tests. The passive haemagglutination test was found to be more sensitive (80%) than the S typhi O antigen (71%) but marginally less sensitive than the H antigen (82%) of the Widal test. The false positive rate on control sera was 1.2% and 6.6%, respectively, for the Widal O and H antigens, and 1.6% for the passive haemagglutination test. Our findings indicate that the passive haemagglutination test is comparable with the Widal test for the serological diagnosis of typhoid fever in endemic areas, but is more simple, rapid, and economic. The passive haemagglutination test may be a useful alternative to the Widal test for the serological diagnosis of typhoid fever in busy microbiology laboratories in areas in which the disease is endemic. PMID:2424936

  4. Evaluation in Papua New Guinea of a urine coagglutination test and a Widal slide agglutination test for rapid diagnosis of typhoid fever.

    PubMed

    West, B; Richens, J E; Howard, P F

    1989-01-01

    Two simple rapid tests for the laboratory diagnosis of typhoid fever were evaluated, a coagglutination test for detecting Salmonella typhi antigens in urine and a Widal slide agglutination for detecting serum antibodies. Ninety-two culture-confirmed typhoid cases were compared with 64 non-typhoid fever patients, 50 close contacts of typhoid patients, 30 vaccinated staff and 72 healthy community members. A strong urine Vi coagglutination was found to be 86.5% sensitive and 91.8% specific for typhoid, but was not always easy to read. The slide Widal H was found to be 99% sensitive and 95% specific whereas the slide Widal O was 98% sensitive and 98% specific. These data suggest that a single slide Widal O, at a reciprocal titre of 40, is the most suitable rapid test for the diagnosis of typhoid in a population with low typhoid antibody levels in the community, few other cross-reacting Salmonella infections, and a tendency for patients to present late in the infection. PMID:2617639

  5. Comparison of an rK39 dipstick rapid test with direct agglutination test and splenic aspiration for the diagnosis of kala-azar in Sudan.

    PubMed

    Veeken, Hans; Ritmeijer, Koert; Seaman, Jill; Davidson, Robert

    2003-02-01

    We compared an rK39 dipstick rapid test (Amrad ICT, Australia) with a direct agglutination test (DAT) and splenic aspirate for the diagnosis of kala-azar in 77 patients. The study was carried out under field conditions in an endemic area of north-east Sudan. The sensitivity of the rK39 test compared with splenic aspiration was 92% (46/50), the specificity 59% (16/27), and the positive predictive value 81% (46/57). Compared with the diagnostic protocol used by Médecins sans Frontières, the sensitivity of the rK39 test was 93% (50/54), the specificity 70% (16/23), and the positive predictive value 88% (50/57). Compared with splenic aspirates, the sensitivity of a DAT with a titre > or =1:400 was 100% (50/50), but its specificity only 55% (15/27) and the positive predictive value was 80% (50/62). Using a DAT titre > or =1:6400, the sensitivity was 84% (42/50), the specificity 85% (23/27) and the positive predictive value 91% (42/46). All four patients with DAT titre > or =1:6400 but negative splenic aspirate were also rK39 positive; we consider these are probably 'true' cases of kala-azar, i.e. false negative aspirates, rather than false DAT and rK39 seropositives. There were no false negative DATs (DAT titre < or =1:400 and aspirate positive), but there were four false negative rK39 tests (rK39 negative and aspirate positive). The rK39 dipstick is a good screening test for kala-azar; but further development is required before it can replace the DAT as a diagnostic test in endemic areas of the Sudan. PMID:12581443

  6. Development and assessment of a latex agglutination test based on recombinant MSP5 to detect antibodies against Anaplasma marginale in cattle

    PubMed Central

    Ramos, Carlos A.N.; Araújo, Flábio R.; Santos, Rafaelle C.; Melo, Elaine S.P.; Sousa, Letícia C.; Vidal, Carlos E.S.; Guerra, Neurisvan R.; Ramos, Rafael A.N.

    2014-01-01

    The recombinant protein MSP5 has been established as an important antigen for serological diagnosis of Anaplasma marginale by enzyme-linked immunosorbent assay (ELISA). However, due to the high cost of specialized equipment, this technique is not accessible to all laboratories, especially in developing countries in areas where the disease is endemic. The present study describes the standardization of a latex agglutination test (LAT) to detect antibodies against A. marginale based on recombinant MSP5. Compared with indirect enzyme-linked immunosorbent assay (iELISA), the relative sensitivity and specificity of the LAT were 95.21% and 91.86% respectively, with an almost perfect agreement between tests (kappa index = 0.863). These results can be considered important for the serological diagnosis of A. marginale, as they indicate that the test represents a rapid and low cost alternative to ELISA. PMID:24948931

  7. Rapid identification of Streptococcus pneumoniae in blood cultures by using the ImmuLex, Slidex and Wellcogen latex agglutination tests and the BinaxNOW antigen test.

    PubMed

    Altun, O; Athlin, S; Almuhayawi, M; Strålin, K; Özenci, V

    2016-04-01

    Rapid identification of Streptococcus pneumoniae in blood culture (BC) bottles is important for early directed antimicrobial therapy in pneumococcal bacteraemia. We evaluated a new latex agglutination (LA) test on BC bottles, the ImmuLex™ S. pneumoniae Omni (Statens Serum Institut, Denmark), and compared the performance with the Slidex® pneumo-Kit (bioMérieux, France) and the Wellcogen™ S. pneumoniae (Remel, UK) LA tests, as well as the BinaxNOW® S. pneumoniae (Alere, USA) antigen test. The four tests were directly applied on 358 positive BC bottles with Gram-positive cocci in pairs or chains and on 15 negative bottles. Valid test results were recorded in all cases for ImmuLex and BinaxNOW and in 88.5 % (330/373) and 94.1 % (351/373) of cases for Slidex and Wellcogen, respectively. Based on bottles positive for S. pneumoniae by conventional methods, the sensitivity of ImmuLex was 99.6 %, similar to the other tests (range, 99.6-100 %). Based on bottles positive for non-pneumococcal pathogens, the specificity of ImmuLex was 82.6 %, in comparison to 97.6 % for Slidex (p < 0.01) and 85.4 % for Wellcogen (p = ns). The BinaxNOW test had a lower specificity (64.1 %) than any LA test (p < 0.01). On BC bottles positive for α-haemolytic streptococci, ImmuLex was positive in 12/67 (17.9 %) cases, Slidex in 2/59 (3.4 %) cases, Wellcogen in 11/64 (17.2 %) cases and BinaxNOW in 25/67 (37.3 %) cases. In conclusion, the ImmuLex test provides a valid and sensitive technique for the rapid detection of S. pneumoniae in BC bottles, similar to the other compared methods. However, the specificity was sub-optimal, since the test may cross-react with other Gram-positive bacteria. PMID:26796552

  8. Sero-epidemiology of equine toxoplasmosis using a latex agglutination test in the three metropolises of Punjab, Pakistan.

    PubMed

    Saqib, M; Hussain, M H; Sajid, M S; Mansoor, M K; Asi, M N; Fadya, A A K; Zohaib, A; Sial, A U R; Muhammad, G; Ullah, I

    2015-06-01

    Toxoplasmosis is a serious threat for livestock in addition to being of zoonotic significance. In this study, serodiagnosis of equine toxoplasmosis was conducted in a randomly selected population from the 3 metropolises of Punjab, Pakistan. To this end, 272 draught equines were screened using a commercial latex agglutination assay kit. Association of probable risk factors of equine toxoplasmosis was also documented. A total of 91 (33.5%) equines were found sero-positive for Toxoplama (T.) gondii having antibody titers ranging between 1:32 to 1:612. The highest rates of seropositive cases were observed in donkeys (58.7%) followed by mules (28.6%) and horses (23.5%). Age, sex and species of draught equines were found not to be statistically (p>0.05) associated with the distribution of T. gondii antibodies. The results of the study provided a baseline data for the exposure of equine population in this area. In addition, it is recommended that the contiguous population of domestic ruminants and possible reservoirs such as feral cats should be screened in order to explore the potential risk for the human population in Pakistan. PMID:26691256

  9. Usefulness of the rK39-Immunochromatographic Test, Direct Agglutination Test, and Leishmanin Skin Test for Detecting Asymptomatic Leishmania Infection in Children in a New Visceral Leishmaniasis Focus in Amhara State, Ethiopia

    PubMed Central

    Gadisa, Endalamaw; Custodio, Estefanía; Cañavate, Carmen; Sordo, Luis; Abebe, Zelalem; Nieto, Javier; Chicharro, Carmen; Aseffa, Abraham; Yamuah, Lawrence; Engers, Howard; Moreno, Javier; Cruz, Israel

    2012-01-01

    In areas where visceral leishmaniasis is anthroponotic, asymptomatically infected patients may play a role in transmission. Additionally, the number of asymptomatic patients in a disease-endemic area will also provide information on transmission dynamics. Libo Kemkem and Fogera districts (Amhara State, Ethiopia) are now considered newly established areas to which visceral leishmaniasis is endemic. In selected villages in these districts, we conducted a study to assess the usefulness of different approaches to estimate the asymptomatic infection rate. Of 605 participants, the rK39 immunochromatographic test was able to detect asymptomatic infection in 1.5% (9 of 605), direct agglutination test in 5.3% (32 of 605), and leishmanin skin test in 5.6% (33 of 589); the combined use of serologic methods and leishmanin skin test enabled detecting asymptomatic infection in 10.1% (61 of 605). We conclude that the best option to detect asymptomatic infection in this new visceral leishmaniasis–endemic focus is the combined use of the direct agglutination test and the leishmanin skin test. PMID:22556076

  10. High detection rates of cryptococcal antigen in pulmonary cryptococcosis by Eiken latex agglutination test with pronase pretreatment.

    PubMed

    Kohno, S; Yasuoka, A; Koga, H; Kaku, M; Maesaki, S; Tanaka, K; Mitsutake, K; Matsuda, H; Hara, K

    1993-08-01

    Two different kits for the detection of serum cryptococcal antigen in patients with pulmonary cryptococcosis were evaluated. The Eiken test (the Eiken Co., Tokyo), which uses pronase for pretreatment of serum, was compared with the Crypto-LA test (International Biological Laboratories, Cranbury, NJ), which did not use pronase prior to testing. Cryptococcal antigen was detected in 21 of 23 patients (91%) with the Eiken test and in only 10 of 23 patients (43%) with the Crypto-LA test (p < 0.01 by McNemar test). However, the sensitivity of two tests was identical without use of pronase, as both tests could detect as little as 10(4) cells/ml of Cryptococcus neoformans and 10 ng/ml of capsular polysaccharide of C. neoformans. In those serum specimens for which both tests were positive, titers were much higher for the Eiken test, but there was a statistically significant correlation between the two tests (coefficient correlation 0.79, p < 0.01). Cryptococcal antigen titer levels measured by the Eiken test correlated well with clinical courses. There was one false-positive reaction among 82 sera of non-cryptococcal patients. Pronase enhanced the sensitivity of the Eiken test, which appeared to be useful in patients with pulmonary cryptococcal disease, and its use may prevent unneeded lung biopsies. PMID:8264770

  11. Evaluation of chromogenic medium and direct latex agglutination test for detection of group B streptococcus in vaginal specimens from pregnant women in Lebanon and Kuwait.

    PubMed

    Ghaddar, Nahed; Alfouzan, Wadha; Anastasiadis, Elie; Al Jiser, Tamima; Itani, Saad Eddine; Dernaika, Racha; Eid, Toufic; Ghaddar, Ali; Charafeddine, Adib; Dhar, Rita; El Hajj, Hiba

    2014-10-01

    This study was undertaken to evaluate chromogenic medium and a direct latex agglutination test (DLA) for detection of Group B Streptococcus (GBS) in the vaginal specimens of pregnant women, and to ascertain the prevalence of GBS in this population in Kuwait and Lebanon. Vaginal swabs, collected from women at 35-37 weeks of gestation, were cultured on 5 % sheep blood agar (SBA), colistin nalidixic acid agar (CNA), Strept B Select chromogenic agar (SBS) as well as Lim enrichment broth in 168 cases in Lebanon while only SBA was used for 1391 samples in Kuwait. In addition, vaginal samples from 102 GBS-positive and 20 GBS-negative women near the time of delivery were collected in Kuwait for evaluation of the DLA test. During the study period, the prevalence of GBS colonization was determined to be 20.7 % (288/1391) in Kuwait while 18.4 % (31) of 168 pregnant women in Lebanon had vaginal cultures positive for GBS. By direct plating of vaginal swabs on the three media used, the isolation rates of GBS were 51.6, 64.5 and 77.4 % on SBA, CNA and SBS, respectively, which increased to 90.35, 93.1 and 96.8 %, respectively, following subculture in Lim broth after 18 h of incubation. The sensitivity of the DLA test was found to be dependent on the density of GBS colonization, resulting in 100 % sensitivity and 100 % specificity for heavy (>10(2) c.f.u. per swab) and moderately heavy (50-100 c.f.u. per swab) growth of GBS. However, for vaginal specimens yielding <50 c.f.u. per swab, the sensitivity, specificity, positive and negative predictive values of the DLA test were 100, 55.5, 63.6 and 100 %, respectively. In conclusion, a chromogenic agar, such as SBS, and a DLA test can be used for rapid detection of GBS in pregnant women. The DLA test, in particular, could prove to be a useful tool for immediate detection of GBS in women near delivery so that intrapartum antibiotic prophylaxis can be initiated. PMID:25082944

  12. Evaluation of ImmunoCard STAT test and ELISA versus light microscopy in diagnosis of giardiasis and cryptosporidiosis.

    PubMed

    Sadaka, H A; Gaafar, M R; Mady, R F; Hezema, N N

    2015-08-01

    This study was designed to evaluate ImmunoCard STAT Cryptosporidium/Giardia rapid assay and ELISA copro-antigen assays in detecting Giardia lamblia and Cryptosporidium species in fecal samples in comparison to microscopy. Both ImmunoCard STAT and ELISA assays were evaluated with 90 stool specimens that were tested by the standard ova and parasite examination including staining with both iron hematoxylin stain and modified Ziehl Neelson stains. Counting the number of Giardia cysts and Cryptosporidia oocysts in the positive stool samples was done in order to quantify the lower limit of parasite number that was able to be detected by all included assays. Both ImmunoCard STAT and ELISA assays were compared on the basis of the attributes which are number of detected cases, sensitivity, specificity, time required for the procedure and screening, ease of performance and interpretation, and cost. Microscopic examination revealed that 13.3% of the samples were positive for Giardia and 2.2% for Cryptosporidium. By ELISA, 16.7% of the samples were infected with Giardia and 3.3% with Cryptosporidium, while by ImmunoCard STAT, 17.8 and 4.45% of the samples were positive for Giardia and Cryptosporidium, respectively. There is no statistically significant difference between the results of ELISA and ImmunoCard STAT assays. The lowest concentration detected in the stool samples was 10.50 ± 1.05 Giardia cysts and 2.83 ± 1.72 Cryptosporidium oocysts. The ImmunoCard STAT was extremely easy to read, thus requiring much less time, but its cost was much higher than ELISA. We concluded that although the overall ranking of both assays was high, the ImmunoCard STAT rapid assay was a more desirable test despite its higher cost. PMID:25924795

  13. [Evaluation of the agglutination test (AT), complement fixation test (CFT) and the antiglobulin test (AGT) in the diagnosis of swine brucellosis. III. Basic studies].

    PubMed

    Karpiński, T M; Zórawski, C; Skwarek, P

    1986-01-01

    In the examinations of the swine sera obtained from swines immunized s.c. with adjuvant Br.abortus S19 vaccine or Br.suis 1417 vaccine, it was found that agglutinins were present after 3 weeks, and C.F. antibodies or incomplete agglutinins normally after injections. Probably, in the first period of Brucella infection negative results of C.F.T. or AGT or both will be obtained. In the swine sera from Brucella free herds, agglutinins reacting with the Brucellognost antigen were present. The performance of mercaptoethanol test or C.F.T. lead in most cases to suitable diagnosis. In our conditions we have not obtained results which permit to classify AGT as a supplement test in serodiagnosis of swine brucellosis. PMID:3822855

  14. Total Automation for the Core Laboratory: Improving the Turnaround Time Helps to Reduce the Volume of Ordered STAT Tests.

    PubMed

    Ialongo, Cristiano; Porzio, Ottavia; Giambini, Ilio; Bernardini, Sergio

    2016-06-01

    The transition to total automation represents the greatest leap for a clinical laboratory, characterized by a totally new philosophy of process management. We have investigated the impact of total automation on core laboratory efficiency and its effects on the clinical services related to STAT tests. For this purpose, a 47-month retrospective study based on the analysis of 44,212 records of STAT cardiac troponin I (CTNI) tests was performed. The core laboratory reached a new efficiency level 3 months after the implementation of total automation. Median turnaround time (TAT) was reduced by 14.9±1.5 min for the emergency department (p < 0.01), reaching 41.6±1.2 min. In non-emergency departments, median TAT was reduced by 19.8±2.2 min (p < 0.01), reaching 52±1.3 min. There was no change in the volume of ordered STAT CTNI tests by the emergency department (p = 0.811), whereas for non-emergency departments there was a reduction of 115.7±50 monthly requests on average (p = 0.026). The volume of ordered tests decreased only in time frames of the regular shift following the morning round. Thus, total automation significantly improves the core laboratory efficiency in terms of TAT. As a consequence, the volume of STAT tests ordered by hospital departments (except for the emergency department) decreased due to reduced duplicated requests. PMID:25882188

  15. Diagnosis of myocardial infarction based on lectin-induced erythrocyte agglutination: a feasibility study

    NASA Astrophysics Data System (ADS)

    Bocsi, József; Nieschke, Kathleen; Mittag, Anja; Reichert, Thomas; Laffers, Wiebke; Marecka, Monika; Pierzchalski, Arkadiusz; Piltz, Joachim; Esche, Hans-Jürgen; Wolf, Günther; Dähnert, Ingo; Baumgartner, Adolf; Tarnok, Attila

    2014-03-01

    Myocardial infarction (MI) is an acute life-threatening disease with a high incidence worldwide. Aim of this study was to test lectin-carbohydrate binding-induced red blood cell (RBC) agglutination as an innovative tool for fast, precise and cost effective diagnosis of MI. Five lectins (Ricinus communis agglutinin (RCA), Phaseolus vulgaris erythroagglutinin (PHA), Datura stramonium agglutinin (DSA), Artocarpus agglutinin (ArA), Triticum agglutinin (TA)) were tested for ability to differentiate between agglutination characteristics in patients with MI (n = 101) or angina pectoris without MI (AP) (n = 34) and healthy volunteers (HV) as control (n =68) . RBC agglutination was analyzed by light absorbance of a stirred RBC suspension in the green to red light spectrum in an agglutimeter (amtec, Leipzig, Germany) for 15 min after lectin addition. Mean cell count in aggregates was estimated from light absorbance by a mathematical model. Each lectin induced RBC agglutination. RCA led to the strongest RBC agglutination (~500 RBCs/aggregate), while the others induced substantially slower agglutination and lead to smaller aggregate sizes (5-150 RBCs/aggregate). For all analyzed lectins the lectin-induced RBC agglutination of MI or AP patients was generally higher than for HV. However, only PHA induced agglutination that clearly distinguished MI from HV. Variance analysis showed that aggregate size after 15 min. agglutination induced by PHA was significantly higher in the MI group (143 RBCs/ aggregate) than in the HV (29 RBC-s/aggregate, p = 0.000). We hypothesize that pathological changes during MI induce modification of the carbohydrate composition on the RBC membrane and thus modify RBC agglutination. Occurrence of carbohydrate-lectin binding sites on RBC membranes provides evidence about MI. Due to significant difference in the rate of agglutination between MI > HV the differentiation between these groups is possible based on PHA-induced RBC-agglutination. This novel assay

  16. Mannanoligosaccharide agglutination by Salmonella enterica strains isolated from carrier pigs

    PubMed Central

    Borowsky, Luciane; Corção, Gertrudes; Cardoso, Marisa

    2009-01-01

    Type-1 fimbriae are associated with most Salmonella enterica serovars and are an essential factor for host colonization. Mannanoligosaccharides (MOS), a prebiotic that is agglutinated by type-1 fimbriae, are proposed for the control of enterobacteria colonization and may be an alternative to Salmonella control in pigs. The aim of this study was to evaluate the capability of porcine Salmonella strains to adhere to MOS in vitro. A total of 108 strains of Salmonella sp. isolated from carrier pigs were evaluated for the amplification of fimA and fimH genes, agglutination of MOS and hemagglutination. In all tested strains, amplicons of expected size were detected for both fimA and fimH gene. In the hemagglutination assays, 31 (28.7%) strains presented mannose–sensitive agglutination of erythrocytes, indicating that the strains were expressing type-1 fimbriae. Considering only strains expressing the type-1 fimbriae, 23 (74.2%) presented a strong agglutination of MOS, 3 (9.6%) a weak reaction and 5 (16.2%) none. The results indicate that Salmonella enterica strains expressing type-1 fimbriae can agglutinate effectively in vitro to MOS. PMID:24031388

  17. Manufacturing High-Fidelity Lunar Agglutinate Simulants

    NASA Technical Reports Server (NTRS)

    Gutafson, R. J.; Edmunson, J. E.; Rickman, D. L.

    2010-01-01

    The lunar regolith is very different from many naturally occurring material on Earth because it forms in the unique, impact-dominated environment of the lunar surface. Lunar regolith is composed of five basic particle types: mineral fragments, pristine crystalline rock fragments, breccia fragments, glasses of various kinds, and agglutinates (glass-bonded aggregates). Agglutinates are abundant in the lunar regolith, especially in mature regoliths where they can be the dominant component.This presentation will discuss the technical feasibility of manufacturing-simulated agglutinate particles that match many of the unique properties of lunar agglutinates.

  18. PrimaTB STAT-PAK Assay, a Novel, Rapid Lateral-Flow Test for Tuberculosis in Nonhuman Primates▿

    PubMed Central

    Lyashchenko, Konstantin P.; Greenwald, Rena; Esfandiari, Javan; Greenwald, David; Nacy, Carol A.; Gibson, Susan; Didier, Peter J.; Washington, Marc; Szczerba, Peter; Motzel, Sherri; Handt, Larry; Pollock, John M.; McNair, James; Andersen, Peter; Langermans, Jan A. M.; Verreck, Frank; Ervin, Sean; Ervin, Frank; McCombs, Candace

    2007-01-01

    Tuberculosis (TB) is the most important zoonotic bacterial disease in nonhuman primates (NHP). The current diagnostic method, the intradermal palpebral tuberculin test, has serious shortcomings. We characterized antibody responses in NHP against Mycobacterium tuberculosis to identify immunodominant antigens and develop a rapid serodiagnostic test for TB. A total of 422 NHP were evaluated, including 243 rhesus (Macaca mulatta), 46 cynomolgus (Macaca fascicularis), and 133 African green (Cercopithecus aethiops sabaeus) monkeys at five collaborative centers. Of those, 50 monkeys of the three species were experimentally inoculated with M. tuberculosis. Antibody responses were monitored every 2 to 4 weeks for up to 8 months postinfection by MultiAntigen Print ImmunoAssay with a panel of 12 recombinant antigens. All of the infected monkeys produced antibodies at various levels and with different antigen recognition patterns. ESAT-6 and MPB83 were the most frequently recognized proteins during infection. A combination of selected antigens which detected antibodies in all of the infected monkeys was designed to develop the PrimaTB STAT-PAK assay by lateral-flow technology. Serological evaluation demonstrated high diagnostic sensitivity (90%) and specificity (99%). The highest rate of TB detection was achieved when the skin test was combined with the PrimaTB STAT-PAK kit. This novel immunoassay provides a simple, rapid, and accurate test for TB in NHP. PMID:17652522

  19. Agglutination of Staphylococcus aureus by Rabbit Sera

    PubMed Central

    Forsgren, Arne; Forsum, Urban

    1972-01-01

    Of 137 Staphylococcus aureus strains, 87 agglutinated in normal rabbit serum. The agglutination was shown to be caused by the Fc-part of immunoglobulin G (IgG). F(ab1)2-fragments of IgG and immunoglobulin M (IgM) in corresponding concentrations were unreactive. The agglutinating strains had a high or moderate content of protein A. Strains with a low content of protein A and protein A-negative mutants did not agglutinate. The importance of the reaction between the Fc part of IgG and protein A for serotyping of S. aureus is demonstrated. Two alternative methods for serotyping S. aureus are suggested, using either F(ab1)2 fragments of IgG or intact IgM. Images PMID:4564678

  20. Conventional Rapid Latex Agglutination in Estimation of von Willebrand Factor: Method Revisited and Potential Clinical Applications

    PubMed Central

    Che Hussin, Che Maraina

    2014-01-01

    Measurement of von Willebrand factor antigen (VWF : Ag) levels is usually performed in a specialised laboratory which limits its application in routine clinical practice. So far, no commercial rapid test kit is available for VWF : Ag estimation. This paper discusses the technical aspect of latex agglutination method which was established to suit the purpose of estimating von Willebrand factor (VWF) levels in the plasma sample. The latex agglutination test can be performed qualitatively and semiquantitatively. Reproducibility, stability, linearity, limit of detection, interference, and method comparison studies were conducted to evaluate the performance of this test. Semiquantitative latex agglutination test was strongly correlated with the reference immunoturbidimetric assay (Spearman's rho = 0.946, P < 0.001, n = 132). A substantial agreement (κ = 0.77) was found between qualitative latex agglutination test and the reference assay. Using the scoring system for the rapid latex test, no agglutination is with 0% VWF : Ag (control negative), 1+ reaction is equivalent to <20% VWF : Ag, and 4+ reaction indicates >150% VWF : Ag (when comparing with immunoturbidimetric assay). The findings from evaluation studies suggest that latex agglutination method is suitable to be used as a rapid test kit for the estimation of VWF : Ag levels in various clinical conditions associated with high levels and low levels of VWF : Ag. PMID:25759835

  1. Field applications of agglutination and cytoadherence assays with Plasmodium falciparum from Papua New Guinea.

    PubMed

    Southwell, B R; Brown, G V; Forsyth, K P; Smith, T; Philip, G; Anders, R

    1989-01-01

    Plasmodium falciparum isolates obtained directly from patients in Papua New Guinea were tested in their first cycle of growth in vitro for adherence to melanoma cells and for susceptibility to agglutination by immune serum. Binding varied among isolates and, in many cases, increased with further rounds of replication under optimal culture conditions. Binding inhibition assays and agglutination assays demonstrated extreme heterogeneity of surface antigens; apparently none of the sera from adult patients recognized all of the variants presented. PMID:2694479

  2. Detection of Delta9-tetrahydrocannabinol and amphetamine-type stimulants in oral fluid using the Rapid Stat point-of-collection drug-testing device.

    PubMed

    Röhrich, J; Zörntlein, S; Becker, J; Urban, R

    2010-04-01

    The Rapid Stat assay, a point-of-collection drug-testing device for detection of amphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines in oral fluid, was evaluated for cannabis and amphetamine-type stimulants. The Rapid Stat tests (n = 134) were applied by police officers in routine traffic checks. Oral fluid and blood samples were analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol, amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyethylamphetamine, and methylenedioxyamphetamine. The comparison of GC-MS analysis of oral fluid with the Rapid Stat results for cannabis showed a sensitivity of 85%, a specificity of 87%, and a total confirmation rate of 87%. When compared with serum, the sensitivity of the cannabis assay decreased to 71%, the specificity to 60%, and the total confirmation rate to 66%. These findings were possibly caused by an incorrect reading of the THC test results. Comparison of the Rapid Stat amphetamine assay with GC-MS in oral fluid showed a sensitivity of 94%, a specificity of 97%, and a total confirmation rate of 97%. Compared with serum, a sensitivity of 100%, a specificity of 90%, and a total confirmation rate of 92% was found. The amphetamine assay must, therefore, be regarded as satisfactory. PMID:20406540

  3. Light-scattering analysis of ultrasonic wave's influence on the RBC agglutination in vitro

    NASA Astrophysics Data System (ADS)

    Doubrovski, Valeri A.; Dvoretski, Costanten N.

    1999-04-01

    Elastic light scattering is one of the most often used optical methods to analyze the cells agglutination reaction - the base of a great number of medical diagnostic test and biomedical investigations. The increase of the resolution of methods and apparatus towards the induced cells aggregation - the foundation of the reaction of agglutination, is quite an actual problem. The solution of this problem increases the reliability of the diagnostic test and gives an opportunity to achieve the diagnostic information in the cases when the traditional approaches do not lead to the diagnostic results. The attempt to increase the resolution of the immune reaction analyzer by means of ultrasonic waves action on the reagent mixture in vitro is taken in this paper. The RBC agglutination reaction which is usually used for the blood group type examination is chosen as an example of an object of the investigation. Different laser optical trains of the devices based on the turbidimetric and nephelometric methods and their combination are analyzed here. The influence of the ultrasonic wave time interval action and of the features of the sample preparation procedure on the resolution towards the agglutination process was investigated in this work. It is shown that the ultrasonic wave action on the reagent mixture leads to a large gain in the resolution of the device towards the RBC agglutination process. The experiments showed that the resolution of the device was enough to register the agglutination process even for the erythrocytes with weak agglutination ability when the reaction was invisible without ultrasonic action. It occurred that the diagnostic test time was more than by an order shortened due to the ultrasonic wave action. The optimal ultrasonic time interval action, the sample preparation technology and experimental technique were defined. The principle of the ultrasonic wave action on the cells agglutination process suggested here can be spread out on the immune

  4. Comparison of staphylococcal coagglutination, latex agglutination, and counterimmunoelectrophoresis for bacterial antigen detection.

    PubMed Central

    Thirumoorthi, M C; Dajani, A S

    1979-01-01

    Soluble antigens of Haemophilus influenzae type b, Streptococcus pneumoniae, Neisseria meningitidis, and group B streptococcus were looked for in cerebrospinal fluid, serum, and urine by using the staphylococcal coagglutination test, latex agglutination test, and counterimmunoelectrophoresis. The staphylococcal coaggultination and latex agglutination tests were more sensitive than counterimmunoelectrophoresis in identifying antigens of H. influenzae type b, S. pneumoniae, and N. meningitidis. None of the three tests successfully detected group B streptococcal antigens in body fluids. Nonspecific reactions noted with the staphylococcal coagglutination test could be usually eliminated after premixing test specimens with soluble protein A. PMID:34622

  5. Paper Towels, Baseball, Puzzles, Nuts & Bolts & the TI-83Plus STAT Tests Menu.

    ERIC Educational Resources Information Center

    Carruth, Barbara

    This collection of activities is designed to show how graphing calculators can be used to explore statistics. The activities address such topics as data representation, distributions, and statistical tests. Teaching notes and calculator instructions are included as are blackline masters. (MM)

  6. Process to create simulated lunar agglutinate particles

    NASA Technical Reports Server (NTRS)

    Gustafson, Robert J. (Inventor); Gustafson, Marty A. (Inventor); White, Brant C. (Inventor)

    2011-01-01

    A method of creating simulated agglutinate particles by applying a heat source sufficient to partially melt a raw material is provided. The raw material is preferably any lunar soil simulant, crushed mineral, mixture of crushed minerals, or similar material, and the heat source creates localized heating of the raw material.

  7. Evaluation of the usefulness of six commercial agglutination assays for serologic diagnosis of toxoplasmosis.

    PubMed

    Villard, Odile; Cimon, Bernard; Franck, Jacqueline; Fricker-Hidalgo, Hélène; Godineau, Nadine; Houze, Sandrine; Paris, Luc; Pelloux, Hervé; Villena, Isabelle; Candolfi, Ermanno

    2012-07-01

    Six agglutination tests for detecting Toxoplasma gondii-specific antibodies (immunoglobulin G or M) in serum were performed and compared. In total, 599 sera were examined using direct and indirect agglutination assays. Sensitivity varied from 93.7% to 100% and specificity from 97.1% to 99.2%. In a selected population with interfering diseases, the percentage of false positives ranged from 4.3% to 10.9%. Although an overall agreement of 100% was found for chronic toxoplasmosis, sensitivity for the detection of confirmed acute toxoplasmosis ranged from 86.4% to 97.3%. Regarding the large variability in terms of the performance of the 6 assays, tests based on the hemagglutination principle were found to be better than the other agglutination tests for all the panels evaluated, meaning that they could be used as qualitative or semiquantitative low-cost screening assays. PMID:22541791

  8. Stat3 inhibition in neural lineage cells.

    PubMed

    Chiba, Tomohiro; Mack, Laura; Delis, Natalia; Brill, Boris; Groner, Bernd

    2012-06-01

    Abstract Deregulation of signal transducer and activator of transcription 3 (Stat3) is attracting attentions in neurological disorders of elderly populations, e.g., Stat3 is inactivated in hippocampal neurons of Alzheimer's disease (AD) brains, whereas it is often constitutively activated in glioblastoma multiforme (GBM), correlating with poor prognosis. Stat3-inhibiting drugs have been intensively developed for chemotherapy based on the fact that GBM, in many cases, are "addicted" to Stat3 activation. Stat3 inhibitors, however, potentially have unfavorable side effects on postmitotic neurons, normal permanent residents in the central nervous system. It is, therefore, of great importance to address detailed cellular responses of neural lineage cells including normal neurons, astrocytes, and neuronal/glial cancer cell lines to several classes of Stat3 inhibitors focusing on their effective concentrations. Here, we picked up five human and mouse cancer cell lines (Neuro-2a and SH-SY5Y neuroblastoma cell lines and Tu-9648, U-87MG, and U-373MG glioblastoma cell lines) and treated with various Stat3 inhibitors. Among them, Stattic, FLLL31, and resveratrol potently suppressed P-Stat3 and cell viability in all the tested cell lines. Stat3 knockdown or expression of dominant-negative Stat3 further sensitized cells to the inhibitors. Expression of familial AD-related mutant amyloid precursor protein sensitized neuronal cells, not glial cells, to Stat3 inhibitors by reducing P-Stat3 levels. Primary neurons and astrocytes also responded to Stat3 inhibitors with similar sensitivities to those observed in cancer cell lines. Thus, Stat3 inhibitors should be carefully targeted to GBM cells to avoid potential neurotoxicity leading to AD-like neuropsychiatric dysfunctions. PMID:25436682

  9. Chemical aspects of agglutinate formation - Relationships between agglutinate composition and the composition of the bulk soil. [lunar surface composition

    NASA Technical Reports Server (NTRS)

    Via, W. N.; Taylor, L. A.

    1976-01-01

    Attention is centered on the nature and intensity of geochemical fractionation accompanying agglutination of several size fractions of the immature Apollo-16 soil sample 67460, from North Ray Crater. The soil features coarse mean grain size about 150 microns, low (20 wt.%) magnetic agglutinate content, and a bimodal grain size distribution. The magnetic fraction included both agglutinates and magnetic non-agglutinates (glass-free microbreccias with 30-60 micron native FeNi grains hosted in a matrix of pyroxene, ilmenite, and olivine). The separation process residue contained nonmagnetic agglutinates with compositions near pure plagioclase. The magnetic agglutinate fraction appears selectively enriched in ferromagnesian elements to the partial exclusion of plagioclase elements. Agglutinate glass chemistry based solely on magnetic separation is deprecated on the basis of the results.

  10. Ultrasensitive Antibody Detection by Agglutination-PCR (ADAP)

    PubMed Central

    2016-01-01

    Antibodies are widely used biomarkers for the diagnosis of many diseases. Assays based on solid-phase immobilization of antigens comprise the majority of clinical platforms for antibody detection, but can be undermined by antigen denaturation and epitope masking. These technological hurdles are especially troublesome in detecting antibodies that bind nonlinear or conformational epitopes, such as anti-insulin antibodies in type 1 diabetes patients and anti-thyroglobulin antibodies associated with thyroid cancers. Radioimmunoassay remains the gold standard for these challenging antibody biomarkers, but the limited multiplexability and reliance on hazardous radioactive reagents have prevented their use outside specialized testing facilities. Here we present an ultrasensitive solution-phase method for detecting antibodies, termed antibody detection by agglutination-PCR (ADAP). Antibodies bind to and agglutinate synthetic antigen–DNA conjugates, enabling ligation of the DNA strands and subsequent quantification by qPCR. ADAP detects zepto- to attomoles of antibodies in 2 μL of sample with a dynamic range spanning 5–6 orders of magnitude. Using ADAP, we detected anti-thyroglobulin autoantibodies from human patient plasma with a 1000-fold increased sensitivity over an FDA-approved radioimmunoassay. Finally, we demonstrate the multiplexability of ADAP by simultaneously detecting multiple antibodies in one experiment. ADAP’s combination of simplicity, sensitivity, broad dynamic range, multiplexability, and use of standard PCR protocols creates new opportunities for the discovery and detection of antibody biomarkers. PMID:27064772

  11. Agglutinates and carbon accumulation in Apollo 17 lunar soils

    NASA Technical Reports Server (NTRS)

    Basu, A.; Meinschein, W. G.

    1976-01-01

    A critical review of maturity with respect to the abundance of implanted solar wind elements (SWE) in lunar soils indicates: (1) that the Rosiwal Principle has limited applicability in determining implantation of SWE in lunar soils, and (2) that despite a depletion of SWE in agglutinitic glass, agglutinates are enriched in SWE due to the presence of buried surfaces of numerous clasts within agglutinates. A statistical analysis of published data of several Apollo 17 soils indicates that the abundance of carbon and, by analogy, the abundance of other SWE are correlatable with the agglutinate content and the mean grain size of lunar soils. Microscopic examination of more than 5000 grains of agglutinates in polished thin sections reveals a wide range of variability in the mineralogy, grain size distribution, degree of recycling, etc., of the clast population in agglutinates. This indicates that the volume-correlated SWE content of agglutinates may vary and need not be constant.

  12. The chemistry of some individual lunar soil agglutinates

    NASA Technical Reports Server (NTRS)

    Gibbons, R. V.; Hoerz, F.; Schaal, R. B.

    1976-01-01

    The inquiry is centered on the composition of agglutinate glasses examined via microprobe techniques. The glass chemistry of the agglutinates is brought into relation with compositions of constituent detritus and bulk compositions of the parent soils, with recent reported results taken into cognizance. Electron microprobe analysis data were examined for possible chemical fractionation resulting from meteoritic impacts and formation of agglutinates in the lunar regolith; individual agglutinates from lunar soils 78222, 71061, and 60009 were probed. Differences between impact glasses and corresponding bulk soils were scrutinized. Agglutinate glass analyses tend to cluster near the bulk soil compositions. A slight enrichment in mafic elements in grand averages of the agglutinate clusters relative to the bulk soils was found. Evidence of total impact melts and minor partial shock melts is examined.

  13. Nitrogen isotopic signatures in agglutinates from breccia 79035

    NASA Technical Reports Server (NTRS)

    Kerridge, John F.; Kim, Yoosook; Kim, Jin S.; Marti, Kurt

    1993-01-01

    Agglutinates in the size range 125-175 microns from regolith breccia 79035 are substantially depleted in N compared with bulk 79035. Isotopically, agglutinate N closely resembles that found previously in ilmenite separates. The minimum (delta)N-15 value found during stepwise pyrolysis of agglutinates is significantly heavier than that observed for bulk 79035. The major host phase for trapped N in 79035, and the host phase of the lightest isotopic component(s), remain unidentified.

  14. Penicillamine prevents ram sperm agglutination in media that support capacitation.

    PubMed

    Leahy, T; Rickard, J P; Aitken, R J; de Graaf, S P

    2016-02-01

    Ram spermatozoa are difficult to capacitate in vitro. Here we describe a further complication, the unreported phenomenon of head-to-head agglutination of ram spermatozoa following dilution in the capacitation medium Tyrodes plus albumin, lactate and pyruvate (TALP). Sperm agglutination is immediate, specific and persistent and is not associated with a loss of motility. Agglutination impedes in vitro sperm handling and analysis. So the objectives of this study were to investigate the cause of sperm agglutination and potential agents which may reduce agglutination. The percentage of non-agglutinated, motile spermatozoa increased when bicarbonate was omitted from complete TALP suggesting that bicarbonate ions stimulate the agglutination process. d-penicillamine (PEN), a nucleophilic thiol, was highly effective at reducing agglutination. The inclusion of 250 μM PEN in TALP reduced the incidence of motile, agglutinated spermatozoa from 76.7 ± 2.7% to 2.8 ± 1.4%. It was then assessed if PEN (1 mM) could be included in existing ram sperm capacitation protocols (TALP +1 mM dibutyryl cAMP, caffeine and theophylline) to produce spermatozoa that were simultaneously capacitated and non-agglutinated. This protocol resulted in a sperm population which displayed high levels of tyrosine phosphorylated proteins and lipid disordered membranes (merocyanine-540) while remaining motile, viable, acrosome-intact and non-agglutinated. In summary, PEN (1 mM) can be included in ram sperm capacitation protocols to reduce sperm agglutination and allow for the in vitro assessment of ram sperm capacitation. PMID:26705263

  15. The Classroom-Friendly ABO Blood Types Kit: Blood Agglutination Simulation

    ERIC Educational Resources Information Center

    Arnold, Savittree Rochanasmita; Kruatong, Tussatrin; Dahsah, Chanyah; Suwanjinda, Duongdearn

    2012-01-01

    The classroom-friendly ABO blood type kit was developed by combining advantages of modelling and a simulation laboratory to teach the topics of ABO blood types and blood transfusion. Teachers can easily simulate the agglutination reaction on a blood type testing plate in the classroom, and show the students how this reaction occurs by using the…

  16. Acanthamoeba castellanii STAT protein.

    PubMed

    Kicinska, Anna; Leluk, Jacek; Jarmuszkiewicz, Wieslawa

    2014-01-01

    STAT (signal transducers and activators of transcription) proteins are one of the important mediators of phosphotyrosine-regulated signaling in metazoan cells. We described the presence of STAT protein in a unicellular, free-living amoebae with a simple life cycle, Acanthamoeba castellanii. A. castellanii is the only, studied to date, Amoebozoan that does not belong to Mycetozoa but possesses STATs. A sequence of the A. castellanii STAT protein includes domains similar to those of the Dictyostelium STAT proteins: a coiled coil (characteristic for Dictyostelium STAT coiled coil), a STAT DNA-binding domain and a Src-homology domain. The search for protein sequences homologous to A. castellanii STAT revealed 17 additional sequences from lower eukaryotes. Interestingly, all of these sequences come from Amoebozoa organisms that belong to either Mycetozoa (slime molds) or Centramoebida. We showed that there are four separated clades within the slime mold STAT proteins. The A. castellanii STAT protein branches next to a group of STATc proteins from Mycetozoa. We also demonstrate that Amoebozoa form a distinct monophyletic lineage within the STAT protein world that is well separated from the other groups. PMID:25338074

  17. Systems, devices, and methods for agglutination assays using sedimentation

    DOEpatents

    Schaff, Ulrich Y.; Sommer, Gregory J.; Singh, Anup K.

    2016-01-26

    Embodiments of the present invention include methods for conducting agglutination assays using sedimentation. Aggregates may be exposed to sedimentation forces and travel through a density medium to a detection area. Microfluidic devices, such as microfluidic disks, are described for conducting the agglutination assays, as are systems for conducting the assays.

  18. MEMS reagent and sample handling procedure: Feasibility of viral antibody detection by passive immune agglutination

    NASA Technical Reports Server (NTRS)

    Bailey, G. D.; Tenoso, H. J.

    1975-01-01

    An attempt was made to develop a test requiring no preadsorption steps for the assessment of antibodies to rubella and mumps viruses using the passive immune agglutination (PIA) method. Both rubella and mumps antigens and antibodies were prepared. Direct PIA tests, using rubella antigen-coated beads, and indirect PIA tests, using rubella antibody-coated beads, were investigated. Attempts, using either method, were unsuccessful. Serum interference along with nonspecific agglutination of beads by the rubella antigen resulted in no specific response under the test conditions investigated. A new, highly sensitive approach, the enzyme immunoassay (EIA) test system, is recommended to overcome the nonspecificity. This system is a logical outgrowth of some of the solid phase work done on MEMS and represents the next generation tests system that can be directly applied to early disease detection and monitoring.

  19. The specificity of antisera against Bordetella pertussis examined by bacterial agglutination.

    PubMed

    Fredriksen, J H; Frøholm, L O; Kjennerud, U

    1987-12-01

    The specificity of conventional, adsorbed antisera against agglutinogens 1, 2, and 3 of Bordetella pertussis was examined by slide agglutination and by agglutination in microtitre wells. Unadsorbed hyperimmune sera showed higher agglutinating activity against autologous or homologous cells than against cells of heterologous serotype. Adsorption of sera with heterologous cells increased the serotype specificity considerably. In spite of extensive adsorption, these anti-agglutinogen sera were still found to cross-react with B. parapertussis and/or B. bronchiseptica strains. Adsorption experiments with B. pertussis hyperimmune sera against serotype 1-, 1.2-, and 1.3-organisms demonstrated that the cross-reacting surface antigens differed from the agglutinogens 1, 2, and 3. Thus, in making species-specific reagents for diagnostic use it may be of value to include adsorption with B. parapertussis and probably with B. bronchiseptica. Limited data indicated that there is no need to use B. avium for adsorption. The agglutination assays were also used to test three monoclonal antibodies stated to be specific for the agglutinogens 1, 2, and 3, respectively. Some anomalous behaviour for the anti-agglutinogen 1 reagent was found, whereas the anti-agglutinogen 2 and 3 reagents corresponded well with the present polyclonal factor sera. PMID:2894108

  20. STAT inhibitors for cancer therapy

    PubMed Central

    2013-01-01

    Signal Transducer and Activator of Transcription (STAT) proteins are a family of cytoplasmic transcription factors consisting of 7 members, STAT1 to STAT6, including STAT5a and STAT5b. STAT proteins are thought to be ideal targets for anti-cancer therapy since cancer cells are more dependent on the STAT activity than their normal counterparts. Inhibitors targeting STAT3 and STAT5 have been developed. These included peptidomimetics, small molecule inhibitors and oligonucleotides. This review summarized advances in preclinical and clinical development of these compounds. PMID:24308725

  1. False-positive cryptococcal antigen latex agglutination caused by disinfectants and soaps.

    PubMed

    Blevins, L B; Fenn, J; Segal, H; Newcomb-Gayman, P; Carroll, K C

    1995-06-01

    Five disinfectants or soaps were tested to determine if any could be responsible for false-positive results obtained with the Latex-Crypto Antigen Detection System kit (Immuno-Mycologics, Inc., Norman, Okla.). Three disinfectants or soaps (Derma soap, 7X, and Bacdown) produced false-positive agglutination after repeated washing of ring slides during testing of a known negative cerebrospinal fluid specimen. PMID:7650214

  2. Serotype assignment by sero-agglutination, ELISA, and PCR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For assessing isolates of Listeria monocytogenes serotype designation is the foremost subtyping method used. Traditionally serotyping has been done with agglutination reactions. In the last decade alternative serotyping methods were described using Enzyme Linked Immunosorbent Assay(ELISA)and Polymer...

  3. Comparison of Phadebact coagglutination, Bactogen latex agglutination, and counterimmunoelectrophoresis for detection of Haemophilus influenzae type b antigens in cerebrospinal fluid.

    PubMed Central

    Collins, J K; Kelly, M T

    1983-01-01

    Cerebrospinal fluid specimens from patients with suspected meningitis were screened with the Phadebact Haemophilus Test (Pharmacia Diagnostics), with Bactogen (Wampole Laboratories), and by counterimmunoelectrophoresis. With culture-positive fluids, Phadebact coagglutination detected 95%, Bactogen latex agglutination detected 91%, and counterimmunoelectrophoresis detected only 79%. Both agglutination techniques were 25-fold more sensitive than counterimmunoelectrophoresis when tested with dilutions of positive fluids. To obtain specific reactions with the Phadebact reagents it was necessary to heat treat (95 degrees C, 5 min) the fluid; with Bactogen and counterimmunoelectrophoresis this was not necessary. PMID:6603467

  4. Antibody blocks acquisition of bacterial colonization through agglutination

    PubMed Central

    Roche, A. M.; Richard, A. L.; Rahkola, J. T.; Janoff, E. N.; Weiser, J. N.

    2014-01-01

    Invasive infection often begins with asymptomatic colonization of mucosal surfaces. A murine model of bacterial colonization with Streptococcus pneumoniae was used to study the mechanism for mucosal protection by immunoglobulin. In previously colonized immune mice, bacteria were rapidly sequestered within large aggregates in the nasal lumen. To further examine the role of bacterial agglutination in protection by specific antibodies, mice were passively immunized with IgG purified from anti-pneumococcal sera or pneumococcal type-specific monoclonal human IgA (hIgA1 or hIgA2). Systemically-delivered IgG accessed the mucosal surface and blocked acquisition of colonization and transmission between littermates. Optimal protection by IgG was independent of Fc fragment and complement and, therefore, did not involve an opsonophagocytic mechanism. Enzymatic digestion or reduction of IgG prior to administration showed that protection required divalent binding that maintained its agglutinating effect. Divalent hIgA1 is cleaved by the pneumococcal member of a family of bacterial proteases that generate monovalent Fabα fragments. Thus, passive immunization with hIgA1 blocked colonization by an IgA1-protease deficient mutant (agglutinated), but not the protease-producing wild-type parent (not agglutinated), whereas protease-resistant hIgA2 agglutinated and blocked colonization by both. Our findings highlight the importance of agglutinating antibodies in mucosal defense and reveal how successful pathogens evade this effect. PMID:24962092

  5. Prevalence of agglutinating antibodies to Sarcocystis neurona in raccoons, Procyon lotor, from the United States.

    PubMed

    Lindsay, D S; Rosypal, A C; Spencer, J A; Cheadle, M A; Zajac, A M; Rupprecht, C; Dubey, J P; Blagburn, B L

    2001-10-24

    Equine protozoal myeloencephalitis (EPM) is the most important protozoal disease of horses in North America and it is caused by Sarcocystis neurona. Natural cases of encephalitis due to S. neurona have been reported in raccoons, Procyon lotor. We examined 99 raccoons for agglutinating antibodies to S. neurona using the S. neurona agglutination test (SAT) employing formalin-fixed merozoites as antigen. Raccoons originated in Florida (N=24, collected in 1996), New Jersey (N=25, collected in 1993), Pennsylvania (N=25, collected in 1999), and Massachusetts (N=25, collected in 1993 and 1994). We found that 58 (58.6%) of the 99 raccoons were positive for antibodies to S. neurona using the SAT; 44 of 99 raccoons (44%) had titers of > or =1:500. This prevalence is similar to the reported seroprevalence of 33-60% for S. neurona antibodies in horses from the United States using the Western blot test. PMID:11698158

  6. Agglutination of human erythrocytes by the interaction of Zn(2+)ion with histidine-651 on the extracellular domain of band 3.

    PubMed

    Kiyotake, Kento; Ochiai, Hideharu; Yamaguchi, Takeo

    2016-05-01

    Clustering of band 3, chloride/bicarbonate exchanger, has been reported in Zn(2+)-treated human erythrocytes. However, the agglutination of human erythrocytes is also induced by the interaction of Zn(2+)ion with histidine on band 3. Identification of histidine that interacts with Zn(2+)ion remains to be determined. The Zn(2+)-induced agglutination of human erythrocytes was unaffected by chymotrypsin cleavage of the small loop region containing His-547 in the extracellular domain of band 3. On the other hand, papain digestion of the large loop region containing His-651 in band 3 inhibited such Zn(2+)-induced agglutination. Moreover, Zn(2+)-induced erythrocyte agglutination was inhibited by the peptide (ARGWVIHPLG) containing His-651, but not by the peptide such as ARGWVIRPLG, which His-651 was substituted by arginine. Among 10 kinds of animal erythrocytes tested, interestingly, no agglutination by Zn(2+)ions was observed in cow cells only that the forth amino acid in the upstream from His-669 on the large loop of cow band 3 is aspartate (Asp-665) instead of glycine. As expected, the agglutination of human erythrocytes by Zn(2+) ions was inhibited in the presence of aspartate. These data indicate that the interaction of Zn(2+) ion with His-651 residue of band 3 plays an important role in the Zn(2+)-induced agglutination of human erythrocytes. PMID:26859120

  7. Seroprevalence and comparison of different serological tests for brucellosis detection in small ruminants

    PubMed Central

    Sadhu, Dashrath B.; Panchasara, H. H.; Chauhan, H. C.; Sutariya, D. R.; Parmar, V. L.; Prajapati, H. B.

    2015-01-01

    Aim: The aim was to study the seroprevalence and efficacy of the different serological tests used for detection of antibody against Brucella species in small ruminants of Banaskantha district of North-Gujarat. Materials and Methods: Total 1000 serum samples comprising of 485 from sheep and 515 from goat tested for detection of antibodies against the Brucella species by three different serological tests viz., Rose bengal plate test (RBPT), Standard tube agglutination test (STAT), and Indirect Enzyme-linked immunosorbent assay (I-ELISA). Results: The seroprevalence of brucellosis in small ruminants was 11.30%, 11.10%, and 8.80% by RBPT, STAT, and I-ELISA, respectively. The seroprevalence of brucellosis was found to be higher in sheep than goats. The sensitivity of RBPT was found slight more than STAT, but the specificity of both tests was same. In this study, the overall agreement of RBPT and STAT with I-ELISA was found 92.50% and 92.30% in small ruminants, respectively. Conclusion: I-ELISA was a better serological test as compared to RBPT and STAT in the sense of sensitivity, specificity, and rapidity and it could be advocated for screening of brucellosis in sheep and goats. PMID:27047135

  8. CPR Facts and Stats

    MedlinePlus

    ... CPR About CPR & First Aid CPR Facts & Stats History of CPR Cardiac Arrest vs. Heart Attack International ... Training Kits RQI AHA Instructors ECC Educational Conferences Programs CPR In Schools Hands-Only CPR ...

  9. Comparison of agglutinating and neutralizing antibodies to serovar hardjo in sows immunized with two commercial whole culture polivalent anti-leptospira bacterins.

    PubMed

    Soto, Francisco Rafael Martins; Pinheiro, Sônia Regina; Morais, Zenaide Maria; Gonçales, Amane Paldês; de Azevedo, Sérgio Santos; Bernardi, Fernanda; Camargo, Sebastião Rodrigues; Vasconcellos, Silvio Arruda

    2008-07-01

    It was performed the comparison of the intensity and duration of agglutinating and neutralizing antibodies to serovar Hardjo in swines vaccinated with two commercial anti-leptospira bacterins. Sows no reactive to 24 Leptospira sp serovars in the microscopic agglutination test (MAT) were divided in three groups: Group A (n=08): received two vaccine A doses with 30 days interval, Group B (n=08) two vaccine B doses with 30 days interval and Group C (n=08): control no vaccinated against leptospirosis.Blood samples were collected each 30 days during six months following the first vaccination. The sera were tested by MAT and growth inhibition test (GIT) to serovar Hardjo in order to evaluate respectively agglutinating and neutralizing antibodies. It was found that neutralizing antibodies persisted for a longer time than the agglutinating ones and that the absence of agglutinating antibodies does not means in the absence of the neutralizing. The peaks of agglutinating antibodies was obtained at least 30 days earlier than that produced by neutralizing. The duration of both kinds of antibodies measured differed between the two bacterines tested. The period for inducing neutralizing antibodies against serovar Hardjo indicated that gilts must be immunized with two doses of whole culture anti-leptospira bacterines applied 30 days each other at least 90 days before the first mating. For the maintenance of hight levels of neutralizing antibodies the revaccinations must be performed every six months after the first vaccination. PMID:24031250

  10. Comparison of agglutinating and neutralizing antibodies to serovar hardjo in sows immunized with two commercial whole culture polivalent anti-leptospira bacterins

    PubMed Central

    Soto, Francisco Rafael Martins; Pinheiro, Sônia Regina; Morais, Zenaide Maria; Gonçales, Amane Paldês; de Azevedo, Sérgio Santos; Bernardi, Fernanda; Camargo, Sebastião Rodrigues; Vasconcellos, Silvio Arruda

    2008-01-01

    It was performed the comparison of the intensity and duration of agglutinating and neutralizing antibodies to serovar Hardjo in swines vaccinated with two commercial anti-leptospira bacterins. Sows no reactive to 24 Leptospira sp serovars in the microscopic agglutination test (MAT) were divided in three groups: Group A (n=08): received two vaccine A doses with 30 days interval, Group B (n=08) two vaccine B doses with 30 days interval and Group C (n=08): control no vaccinated against leptospirosis.Blood samples were collected each 30 days during six months following the first vaccination. The sera were tested by MAT and growth inhibition test (GIT) to serovar Hardjo in order to evaluate respectively agglutinating and neutralizing antibodies. It was found that neutralizing antibodies persisted for a longer time than the agglutinating ones and that the absence of agglutinating antibodies does not means in the absence of the neutralizing. The peaks of agglutinating antibodies was obtained at least 30 days earlier than that produced by neutralizing. The duration of both kinds of antibodies measured differed between the two bacterines tested. The period for inducing neutralizing antibodies against serovar Hardjo indicated that gilts must be immunized with two doses of whole culture anti-leptospira bacterines applied 30 days each other at least 90 days before the first mating. For the maintenance of hight levels of neutralizing antibodies the revaccinations must be performed every six months after the first vaccination. PMID:24031250

  11. Detection of Salmonella enterica serovar Enteritidis (SE) Antibodies in Serum Using A Polystyrene Bead/SE Flagella Agglutination Assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Serologic screening of flocks can be an important method to detect Salmonella enteritidis (SE) infections but can be labor intensive or lack specificity. Our goal was to develop a rapid agglutination assay using SE flagella adsorbed to polystyrene beads as a simple, relatively specific test to dete...

  12. Enhanced agglutination reaction of ABO subgroups by gold nanoparticle solution: implication for identification of ABO subgroups.

    PubMed

    Ammaranond, P; Sriyarak, J; Saejong, S; Deesin, P; Seereemaspun, A; Rojanathanes, R

    2011-12-01

    Although the ABO blood group is the most significant in blood group system in human, other subgroups system is also important to be concerned in blood banking laboratory. ABO subgroups have weak antigen potency on red blood cell. In some cases, they could not been detected by cell grouping and serum grouping methods. This may lead to misinterpretation of ABO typing which will cause serious problems for transfusion and transplantation. Gold nanoparticle solution can increase the agglutination reaction of ABO typing. Thus far, the investigation of ABO blood group system has been performed using gold nanoparticle solution. Samples were tested comparing between with and without gold nanoparticle solution. After reading the agglutination reaction, supernatants were collected and measured at the optical density at 760 nm by spectrophotometer. The optical density of 2-5% cell suspension and monoclonal antibody was higher than in the tube of 2-5% cell suspension, monoclonal antibody and gold nanoparticle solution. By adding the gold nanoparticle solution, the agglutination reaction was increased ranging from 7.0-37.7% (median 15.0%) for ABO grouping system whereas 12.1-50.9% (median 23.4%) was observed in ABO subgroups. It could decrease the chance of misinterpretation by 33.3%. By using gold nanoparticle solution might be the alternative way for investigation of weak antigen potency on red blood cell. PMID:22416584

  13. Lack of chemical fractionation in major and minor elements during agglutinate formation. [in lunar soil

    NASA Technical Reports Server (NTRS)

    Hu, H.-N.; Taylor, L. A.

    1977-01-01

    Rhodes et al. (1975, 1976) and Adams et al. (1975) have reported that the agglutinate fraction of the soils on the lunar surface displays a marked enrichment in Fe, Mg, Ti, K, and La, and a depletion in Ca, Na, Al, and Eu, relative to the bulk soils. The reported investigation is concerned with a testing of the theory of chemical fractionation involving magnetic separation which was developed in connection with these findings. Soils 64421 and 71501 were sieved and the magnetic fractions separated according to the method developed by Adams and McCord (1973). Analyses of agglutinitic glass did not indicate any appreciable chemical fractionation for the major and minor elements accompanying the agglutination process. It was found that most, if not all fractionations reported can be accounted for completely by the magnetic nonagglutinate impurities in the agglutinate fraction. It is, therefore, concluded that there appears to be no reason to make use of any chemical fractionation theory, whose validity remains to be demonstrated.

  14. Studying red blood cell agglutination by measuring membrane viscosity with optical tweezers

    NASA Astrophysics Data System (ADS)

    Fernandes, Heloise P.; Fontes, Adriana; de Thomaz, André A.; Barbosa, Luiz C.; Barjas-Castro, Maria L.; Cesar, Carlos L.

    2007-09-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycoproteins embedded in a fluid lipid bilayer that are responsible for cell agglutination. Manipulating RBCs rouleaux with a double optical tweezers, we observed that the cells slide easily one over the others but are strongly connected by their edges. An explanation for this behavior could be the fact that when the cells slide one over the others, proteins are dragged through the membrane. It confers to the movement a viscous characteristic that is dependent of the velocity between the RBCs and justifies why is so easy to slide them apart. Therefore, in a first step of this work, by measuring the force as a function of the relative velocity between two cells, we confirmed this assumption and used this viscous characteristic of the RBC rouleaux to determine the apparent membrane viscosity of the cell. As this behavior is related to the proteins interactions, we can use the apparent membrane viscosity to obtain a better understanding about cell agglutination. Methods related to cell agglutination induced by antigen-antibody interactions are the basis of most of tests used in transfusion centers. Then, in a second step of this work, we measured the apparent membrane viscosity using antibodies. We observed that this methodology is sensitive to different kinds of bindings between RBCs. Better comprehension of the forces and bindings between RBCs could improve the sensibility and specificity of the hemagglutination reactions and also guides the development of new potentiator substances.

  15. Evolution of carbon isotopes, agglutinates, and the lunar regolith

    NASA Technical Reports Server (NTRS)

    Desmarais, D. J.; Basu, A.; Hayes, J. M.; Meinschein, W. G.

    1975-01-01

    Apollo 17 light-mantle soils and Apollo 15 Apennine Front soils are compared with respect to isotopic enrichment of C-13 and the maturity of the site. Analyses of soil-size fractions indicate that while the carbon concentration on particle surfaces remains relatively constant with increasing soil maturity, total surface-correlated carbon increases due to increasing total soil surface area. The role of agglutinates in the incorporation of surface-correlated carbon into aggregate grains is examined; agglutinates contain a major percentage of the carbon found in mature soil, and the volume-correlated carbon component in agglutinates apparently continues to increase after the surface-correlated carbon concentrations have reached a constant value. Constraints that may limit the carbon concentration in lunar soils to a value not greater than 300 micrograms/g are considered.

  16. Interaction of mumps virus V protein variants with STAT1-STAT2 heterodimer: experimental and theoretical studies

    PubMed Central

    2010-01-01

    Background Mumps virus V protein has the ability to inhibit the interferon-mediated antiviral response by inducing degradation of STAT proteins. Two virus variants purified from Urabe AM9 mumps virus vaccine differ in their replication and transcription efficiency in cells primed with interferon. Virus susceptibility to IFN was associated with insertion of a non-coded glycine at position 156 in the V protein (VGly) of one virus variant, whereas resistance to IFN was associated with preservation of wild-type phenotype in the V protein (VWT) of the other variant. Results VWT and VGly variants of mumps virus were cloned and sequenced from Urabe AM9 vaccine strain. VGly differs from VWT protein because it possesses an amino acid change Gln103Pro (Pro103) and the Gly156 insertion. The effect of V protein variants on components of the interferon-stimulated gene factor 3 (ISGF3), STAT1 and STAT2 proteins were experimentally tested in cervical carcinoma cell lines. Expression of VWT protein decreased STAT1 phosphorylation, whereas VGly had no inhibitory effect on either STAT1 or STAT2 phosphorylation. For theoretical analysis of the interaction between V proteins and STAT proteins, 3D structural models of VWT and VGly were predicted by comparing with simian virus 5 (SV5) V protein structure in complex with STAT1-STAT2 heterodimer. In silico analysis showed that VWT-STAT1-STAT2 complex occurs through the V protein Trp-motif (W174, W178, W189) and Glu95 residue close to the Arg409 and Lys415 of the nuclear localization signal (NLS) of STAT2, leaving exposed STAT1 Lys residues (K85, K87, K296, K413, K525, K679, K685), which are susceptible to proteasome degradation. In contrast, the interaction between VGly and STAT1-STAT2 heterodimer occurs in a region far from the NLS of STAT2 without blocking of Lys residues in both STAT1 and STAT2. Conclusions Our results suggest that VWT protein of Urabe AM9 strain of mumps virus may be more efficient than VGly to inactivate both the IFN

  17. Evolution of Shock Melt Compositions in Lunar Agglutinates

    NASA Technical Reports Server (NTRS)

    Vance, A. M.; Christoffersen, R.; Keller, L. P.

    2015-01-01

    Lunar agglutinates are aggregates of regolith grains fused together in a glassy matrix of shock melt produced during smaller-scale (mostly micrometeorite) impacts. Agglutinate formation is a key space weathering process under which the optically-active component of nanophase metallic Fe (npFe(sup 0)) is added to the lunar regolith. Here we have used energy-dispersive X-ray (EDX) compositional spectrum imaging in the SEM to quantify the chemical homogeneity of agglutinitic glass, correlate its homogeneity to its parent soil maturity, and identify the principle chemical components contributing to the shock melt compositional variations.

  18. B lymphocytes from patients with chronic lymphocytic leukemia contain signal transducer and activator of transcription (STAT) 1 and STAT3 constitutively phosphorylated on serine residues.

    PubMed

    Frank, D A; Mahajan, S; Ritz, J

    1997-12-15

    To explore the pathogenesis of chronic lymphocytic leukemia (CLL), we examined whether phosphorylation of one or more signal transducer and activator of transcription (STAT) factors was abnormal in cells from CLL patients. No constitutive tyrosine phosphorylation was detected on any STAT in CLL cells. To assess the phosphorylation of serine residues of STAT1 and STAT3 in CLL cells, we raised antibodies that specifically recognize the form of STAT1 phosphorylated on ser-727 and the form of STAT3 phosphorylated on ser-727. We found that in 100% of patients with CLL (n = 32), STAT1 and STAT3 were constitutively phosphorylated on serine. This was in contrast to normal peripheral blood B lymphocytes or CD5+) B cells isolated from tonsils, in which this phosphorylation was absent. Serine phosphorylation of STAT1 and STAT3 was seen occasionally in other leukemias, but it was a universal finding only in CLL. The serine phosphorylation of these STATs was a continuous process, as incubation of CLL cells with the kinase inhibitor H7 led to the dephosphorylation of these serine residues. The STAT serine kinase in CLL cells has not been identified, and appears to be neither mitogen-activated protein kinase nor pp70(s6k). In summary, the constitutive serine phosphorylation of STAT1 and STAT3 is present in all CLL samples tested to date, although the physiologic significance of this modification remains to be determined. PMID:9399961

  19. Targeting STAT3 in cancer: how successful are we?

    PubMed Central

    Yue, Peibin; Turkson, James

    2008-01-01

    Background Aberrant activation of the signal transducer and activator of transcription (STAT)3 occurs in many human tumors. Moreover, studies utilizing genetic and pharmacological approaches to modulate constitutive STAT3 activity have provided compelling evidence for the critical role of aberrant STAT3 activity in malignant transformation and tumor progression, and thereby validated STAT3 as a novel cancer drug target. Objective This review is intended to be a full coverage of the efforts to develop direct STAT3 inhibitors and will provide a discussion on the inhibitory modalities developed to date. Methods Review of the literature focused on the modalities and mechanisms that directly target and inhibit the STAT protein or its functions. Results/conclusion While a variety of STAT3 inhibitors have been identified that induce antitumor cell effects in vitro and in vivo, the landscape remains murky. With a few exceptions, most of the STAT3 inhibitors reported to date have not undergone an in vivo efficacy, pharmacology or toxicity testing. Also, there is no evidence, per the published literature of an impending clinical development for the few agents that were reported to exhibit in vivo efficacy. Overall, there is the need for a reassessment of the ongoing strategies to target STAT3 intended not only for refinement, but also for incorporating some new technologies to strengthen our efforts and ensure the success – sooner, rather than later – of identifying suitable anti-STAT3 agents for development into clinically useful anticancer therapeutics. PMID:19053881

  20. Agglutinating serum for distinguishing Staphylococcus aureus of human biotype.

    PubMed

    Live, I

    1975-08-01

    Antiserum to Staphylococcus aureus strain 17 was treated with S. aureus strain 61218 until the antibodies against thermostable agglutinogen were removed. The absorbed serum agglutinated phage-typable as well as phageuntypable staphylococci of human biotype, whether recovered from people or from dogs. PMID:125241

  1. Synthesis for Lunar Simulants: Glass, Agglutinate, Plagioclase, Breccia

    NASA Technical Reports Server (NTRS)

    Weinstein, Michael; Wilson, Stephen A.; Rickman, Douglas L.; Stoeser, Douglas

    2012-01-01

    The video describes a process for making glass for lunar regolith simulants that was developed from a patented glass-producing technology. Glass composition can be matched to simulant design and specification. Production of glass, pseudo agglutinates, plagioclase, and breccias is demonstrated. The system is capable of producing hundreds of kilograms of high quality glass and simulants per day.

  2. [Agglutination of hen egg-yolk immunoglobulins (IgY) against Salmonella enterica, serovar enteritidis].

    PubMed

    Terzolo, H R; Sandoval, V E; Caffer, M I; Terragno, R; Alcain, A

    1998-01-01

    Two groups of 6 laying hens were used to produce IgY. In the vaccinated group (V), hens were injected by intramuscular route with two doses of a Salmonella enterica serovar Enteritidis bacterin at 20-day interval. In the control group (T) hens remained unvaccinated. Four IgY extractions were performed on the egg production of both groups. The first two extractions were carried out using the yolks obtained from the eggs produced during the 4th and 5th post-vaccination week (extracts 1V and 1T) and the other two using the ones from the 6th, 7th and 8th week (2V and 2T). Starting from the extracts 1V and 1T other products were obtained by freezing-thawing (1V-A and 1T-A) and simple (1V-B and 1T-B) or double (1V-C and 1T-C) flow capillary dialysis concentration. All these products were compared using an ELISA test specific for the detection of chicken antibodies against flagellar antigens of S. Enteritidis. In this test, V extracts were positive whereas T extracts were negative. The extract 1V was more positive than the extract 2V. The extract 1V-C was the most positive and was therefore selected to be used as an antiserum in the agglutination tests. This extract contained 1.9 g/dl of total proteins, 0.028 g/dl of triglycerides and 0.012 g/dl of cholesterol and showed an electrophoretic pattern characteristic of IgY. The 1T-C extract was used as a negative control in the agglutination tests. Slide somatic and tube flagellar agglutination tests were simultaneously carried out using both IgY extracts and a standard rabbit anti-Salmonella (IgG) sera. Overall 367 strains from the Enterobacteriaceae family were tested together with two other strains belonging to the Vibrionaceae family. The 1V-C extract specifically agglutinated S. Enteritidis strains in the same way as the rabbit sera. This extract also agglutinated other Salmonella strains antigenically related to S. Enteritidis. Salmonella which did not share somatic or flagellar antigens with S. Enteritidis, other

  3. Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

    SciTech Connect

    Laul, J.C.; Smith, M.R.

    1984-11-15

    Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

  4. Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

    NASA Technical Reports Server (NTRS)

    Laul, J. C.; Smith, M. R.; Papike, J. J.; Simon, S. B.

    1984-01-01

    Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

  5. Structural Tailoring of Advanced Turboprops (STAT)

    NASA Technical Reports Server (NTRS)

    Brown, Kenneth W.

    1988-01-01

    This interim report describes the progress achieved in the structural Tailoring of Advanced Turboprops (STAT) program which was developed to perform numerical optimizations on highly swept propfan blades. The optimization procedure seeks to minimize an objective function, defined as either direct operating cost or aeroelastic differences between a blade and its scaled model, by tuning internal and external geometry variables that must satisfy realistic blade design constraints. This report provides a detailed description of the input, optimization procedures, approximate analyses and refined analyses, as well as validation test cases for the STAT program. In addition, conclusions and recommendations are summarized.

  6. [STAT3 inhibitor].

    PubMed

    Kitamura, Toshio

    2011-01-01

    Clinical efficacies of various molecular-targeted drugs have been recently demonstrated. Most of these drugs are kinase inhibitors. A most successful drug Glivec is an inhibitor of Bcr-Abl fusion kinase, derived from a well-known causative chromosome translocation of chronic myeloid leukemia(CML). Although other kinase inhibitors have also proved to be useful in the therapy of malignant diseases including an ALK inhibitor for lung carcinomas, a general problem of kinase inhibitors is their lowspecificities. Therefore, the complication of these drugs must be overcome. Recently, trials to develop moleculartargeted therapy whose targets are molecules other than kinases have also been promising. Among molecular targets, STAT3 has attracted a great deal of researchers' attention because it is constitutively activated in most malignant tumors and plays important roles in carcinogenesis. This article summarizes the current situation and problems to be solved with STAT3 inhibitors as well as our recent findings on the molecular mechanisms of STAT3 activation. PMID:21368456

  7. Concanavalin A-induced agglutination of human leukemic and lymphoma cells.

    PubMed

    Maca, R D

    1976-04-01

    With a newly developed turbidometric method, concanavalin A was shown to agglutinate normal lymphocytes, lymphoma cells, and leukemic cells from chronic lymphocytic leukemia and from acute myelocytic and lymphocytic leukemia. However, there was a marked difference in the kinetics of this agglutination process. Leukemic blast cells and cells from a patient with convoluted lymphoma agglutinated poorly in this system. Conversely, the degree of agglutination for chronic lymphocytic leukemia cells was greater than that for the blast cells and also slightly greater than that for normal lymphocytes. Cultured cells from a Burkitt's lymphoma (Raji) and from a patient with poorly differentiated lymphoma agglutinated very rapidly with concanavalin A. Prior incubation of all cell types with neuraminidase markedly enhanced the agglutination process similar to that of trypsinization. Thus, these studies illustrate the usefulness of this method in quantitating the kinetics of agglutination of various human neoplastic cell types by concanavalin A. PMID:1063062

  8. Serotyping of Streptococcus pneumoniae by agglutination assays: a cost-effective technique for developing countries.

    PubMed Central

    Lalitha, M. K.; Pai, R.; John, T. J.; Thomas, K.; Jesudason, M. V.; Brahmadathan, K. N.; Sridharan, G.; Steinhoff, M. C.

    1996-01-01

    There is a need for additional data on the distribution of pneumococcal serotypes in developing countries. We report the use of a coagglutination (COA) and a latex agglutination (LA) test for serotyping Streptococcus pneumoniae which were evaluated using 114 clinical isolates in Vellore, India. In tests to serotype 30 fresh isolates of pneumococci from meningitis (8 isolates), bacteraemia/septicaemia (21 isolates) and peritonitis (1 isolate) cases, there was complete concordance among the three methods. An additional 20 isolates (11 from cerebrospinal fluid and 9 from blood cultures) were serotyped using both LA and COA, with full agreement between the results. With a further 30 isolates, there was 93% concordance for the COA types with serotypes assigned by a WHO reference laboratory. The COA and LA serotyping results were equivalent in accuracy to those obtained using quellung serotyping. Both these agglutination tests are rapid, valid, and relatively cheap, and with appropriate validation by reference laboratories they could be more widely used in developing countries to obtain local and regional data on pneumococcal serotype distribution. PMID:8823960

  9. Use of commercial extenders and alternatives to prevent sperm agglutination for cryopreservation of brown bear semen.

    PubMed

    Gomes-Alves, S; Alvarez, M; Nicolas, M; Lopez-Urueña, E; Martínez-Rodríguez, C; Borragan, S; de Paz, P; Anel, L

    2014-08-01

    The objective of this study was to evaluate different bovine and canine commercial semen extenders for cryopreservation of brown bear ejaculates and the effect of semen collection directly into extender on sperm agglutination. Semen samples were obtained by electroejaculation from 13 adult males. In experiment 1, eleven ejaculates from eight bears were used to evaluate Bioxcell and Andromed as extenders, whereas in experiment 2, nine ejaculates from six bears were used to evaluate Triladyl canine, CaniPro, and Extender 2 as extenders. An extender specifically developed for brown bears (Test-Tris-fructose-egg yolk-glycerol, TTF-ULE/bear) served as a control extender in both experiments. After thawing, total and progressive sperm motility and sperm viability were greater (P < 0.05) for TTF-ULE/bear and Andromed extenders than for Bioxcell in experiment 1 and greater (P < 0.05) for TTF-ULE/bear extender than for Triladyl Canine, CaniPro, and Extender 2 in experiment 2. In experiment 3, addition of handling extender (TTF-H) to the semen collection tube for eight ejaculates from seven bears resulted in less (P < 0.05) sperm agglutination in fresh samples (score 0.5 ± 0.2 vs. 1.8 ± 0.4 in diluted and control samples, respectively) with no effect on pre-freeze and post-thawing semen quality. In conclusion, TTF-ULE/bear is the most suitable extender for brown bear semen cryopreservation, but comparable results can be obtained with the commercial extender Andromed. In addition, collection of ejaculates directly in TTF-H extender decreases sperm agglutination in fresh samples. PMID:24950618

  10. Mononucleosis spot test

    MedlinePlus

    Monospot test; Heterophile antibody test; Heterophile agglutination test; Paul-Bunnell test; Forssman antibody test ... back of the neck This test looks for antibodies called heterophile antibodies, which form in the body ...

  11. Mononucleosis spot test

    MedlinePlus

    Monospot test; Heterophile antibody test; Heterophile agglutination test; Paul-Bunnell test; Forssman antibody test ... The mononucleosis spot test is done when symptoms of mononucleosis are ... Fatigue Fever Large spleen (possibly) Sore throat Tender ...

  12. Tagging of Genomic STAT3 and STAT1 with Fluorescent Proteins and Insertion of a Luciferase Reporter in the Cyclin D1 Gene Provides a Modified A549 Cell Line to Screen for Selective STAT3 Inhibitors

    PubMed Central

    Samsonov, Andrey; Zenser, Nathan; Zhang, Fan; Zhang, Hongyi; Fetter, John; Malkov, Dmitry

    2013-01-01

    Signal transducer and activator of transcription 3 (STAT3) is an oncogenic protein that is constitutively activated in numerous cancer cell lines and human cancers. Another STAT family member, STAT1, possesses cancer-inhibitory properties and can promote apoptosis in tumor cells upon activation. To better characterize these important cancer related genes, we tagged STAT3 and STAT1 loci with fluorescent protein (FP) sequences (RFP and GFP respectively) by targeted integration via zinc finger nuclease (ZFN) - mediated homologous recombination in A549 cells that express aberrantly activated STAT3. We inserted the FP transgenes at the N-terminus of the STAT3 locus and at the C-terminus of the STAT1 locus. The integration resulted in endogenous expression of fluorescent STAT3 and STAT1 chimeric fusion proteins. When stimulated with IL-6 or IFN-γ, the cells showed robust nuclear translocation of RFP-STAT3 or STAT1-GFP, respectively. Pre-incubation of cells with a known specific STAT3 inhibitor showed that IFN-γ-induced translocation of STAT1-GFP was not impaired. STAT3 activates multiple downstream targets such as genes involved in cell cycle progression - e.g. cyclin D1. To detect changes in expression of endogenous cyclin D1, we used ZFN technology to insert a secreted luciferase reporter behind the cyclin D1 promoter and separated the luciferase and cyclin D1 coding regions by a 2A sequence to induce a translational skip. The luciferase insertion was made in the RFP-STAT3/STAT1-GFP cell line to have all three reporters in a single cell line. Addition of a STAT3 inhibitor led to suppression of cyclin D1 promoter activity and cell growth arrest. The triple-modified cell line provides a simple and convenient method for high-content screening and pre-clinical testing of potential STAT3 inhibitors in live cells while ensuring that the STAT1 pathway is not affected. This approach of reporting endogenous gene activities using ZFN technology could be applied to other cancer

  13. Evaluation of Polysaccharide-Based Latex Agglutination Assays for the Rapid Detection of Antibodies to Burkholderia pseudomallei.

    PubMed

    Suttisunhakul, Vichaya; Chantratita, Narisara; Wikraiphat, Chanthiwa; Wuthiekanun, Vanaporn; Douglas, Zakiya; Day, Nicholas P J; Limmathurotsakul, Direk; Brett, Paul J; Burtnick, Mary N

    2015-09-01

    Melioidosis is a severe disease caused by the Gram-negative bacterium Burkholderia pseudomallei. Diagnosis of melioidosis currently relies on the isolation of B. pseudomallei from clinical samples, which can take several days. An indirect hemagglutination assay (IHA) is widely used for serodiagnosis, but it has a short shelf life, is poorly standardized, and requires a viable bacteria culture performed in a biosafety level 3 (BSL-3) laboratory. To improve the diagnostic methods, we have developed two rapid latex agglutination tests based on purified B. pseudomallei O-polysaccharide (OPS) and capsular polysaccharide (CPS) antigens. The immunodiagnostic potential of these tests was evaluated using serum from culture-confirmed melioidosis patients (N = 143) and healthy donors from either endemic (N = 199) or non-endemic areas (N = 90). The sensitivity of the OPS-based latex agglutination assay (OPS-latex; 84.4%) was significantly higher than both the CPS-latex (69.5%) (P < 0.001) and IHA (69.5%) (P = 0.001). When evaluated with Thai donor serum, the OPS-latex had comparable specificity (56.9%) to the CPS-latex (63.8%) (P = 0.053), but was significantly lower than the IHA (67.6%) (P = 0.002). In contrast, all tests with U.S. donor serum were highly specific (≥ 97.8%). These results suggest that polysaccharide-based latex agglutination assays may be useful for serodiagnosis of melioidosis in non-endemic areas. PMID:26123956

  14. Evaluation of Polysaccharide-Based Latex Agglutination Assays for the Rapid Detection of Antibodies to Burkholderia pseudomallei

    PubMed Central

    Suttisunhakul, Vichaya; Chantratita, Narisara; Wikraiphat, Chanthiwa; Wuthiekanun, Vanaporn; Douglas, Zakiya; Day, Nicholas P. J.; Limmathurotsakul, Direk; Brett, Paul J.; Burtnick, Mary N.

    2015-01-01

    Melioidosis is a severe disease caused by the Gram-negative bacterium Burkholderia pseudomallei. Diagnosis of melioidosis currently relies on the isolation of B. pseudomallei from clinical samples, which can take several days. An indirect hemagglutination assay (IHA) is widely used for serodiagnosis, but it has a short shelf life, is poorly standardized, and requires a viable bacteria culture performed in a biosafety level 3 (BSL-3) laboratory. To improve the diagnostic methods, we have developed two rapid latex agglutination tests based on purified B. pseudomallei O-polysaccharide (OPS) and capsular polysaccharide (CPS) antigens. The immunodiagnostic potential of these tests was evaluated using serum from culture-confirmed melioidosis patients (N = 143) and healthy donors from either endemic (N = 199) or non-endemic areas (N = 90). The sensitivity of the OPS-based latex agglutination assay (OPS-latex; 84.4%) was significantly higher than both the CPS-latex (69.5%) (P < 0.001) and IHA (69.5%) (P = 0.001). When evaluated with Thai donor serum, the OPS-latex had comparable specificity (56.9%) to the CPS-latex (63.8%) (P = 0.053), but was significantly lower than the IHA (67.6%) (P = 0.002). In contrast, all tests with U.S. donor serum were highly specific (≥ 97.8%). These results suggest that polysaccharide-based latex agglutination assays may be useful for serodiagnosis of melioidosis in non-endemic areas. PMID:26123956

  15. Serological tests as indicators of immunity against Pasteurella multocida infection in sheep.

    PubMed Central

    Dua, S K; PandurangaRao, C C

    1978-01-01

    Five serological tests, i.e. single tube agglutination, doubling dilution tube agglutination, agar agglutination, passive hemagglutination and passive mouse protection tests were evaluated for their efficacy in predicting the fate of vaccinated and unvaccinated sheep on challenge with an ovine strain of Pasteurella multocida. The passive hemagglutination test predicted the fate of unvaccinated sheep while the agar agglutination test indicated the immune status of vaccinated sheep. PMID:743601

  16. Amyloidogenic amyloid-β-peptide variants induce microbial agglutination and exert antimicrobial activity.

    PubMed

    Spitzer, Philipp; Condic, Mateja; Herrmann, Martin; Oberstein, Timo Jan; Scharin-Mehlmann, Marina; Gilbert, Daniel F; Friedrich, Oliver; Grömer, Teja; Kornhuber, Johannes; Lang, Roland; Maler, Juan Manuel

    2016-01-01

    Amyloid-β (Aβ) peptides are the main components of the plaques found in the brains of patients with Alzheimer's disease. However, Aβ peptides are also detectable in secretory compartments and peripheral blood contains a complex mixture of more than 40 different modified and/or N- and C-terminally truncated Aβ peptides. Recently, anti-infective properties of Aβ peptides have been reported. Here, we investigated the interaction of Aβ peptides of different lengths with various bacterial strains and the yeast Candida albicans. The amyloidogenic peptides Aβ1-42, Aβ2-42, and Aβ3p-42 but not the non-amyloidogenic peptides Aβ1-40 and Aβ2-40 bound to microbial surfaces. As observed by immunocytochemistry, scanning electron microscopy and Gram staining, treatment of several bacterial strains and Candida albicans with Aβ peptide variants ending at position 42 (Aβx-42) caused the formation of large agglutinates. These aggregates were not detected after incubation with Aβx-40. Furthermore, Aβx-42 exerted an antimicrobial activity on all tested pathogens, killing up to 80% of microorganisms within 6 h. Aβ1-40 only had a moderate antimicrobial activity against C. albicans. Agglutination of Aβ1-42 was accelerated in the presence of microorganisms. These data demonstrate that the amyloidogenic Aβx-42 variants have antimicrobial activity and may therefore act as antimicrobial peptides in the immune system. PMID:27624303

  17. Prevalence of agglutinating antibodies to Toxoplasma gondii and Sarcocystis neurona in beavers (Castor canadensis) from Massachusetts

    USGS Publications Warehouse

    Jordan, C.N.; Kaur, T.; Koenen, K.; DeStefano, S.; Zajac, A.M.; Lindsay, D.S.

    2005-01-01

    The present study examined the seroprevalence of Toxoplasma gondii and Sarcocystls neurona in a population of beavers (Castor canadensis) from Massachusetts. Sixty-two blood samples were collected during the field seasons over 3 consecutive years from different animals. Blood was collected onto filter paper and shipped to the Department of Biomedical Sciences, Virginia Tech, Blacksburg, Virginia, for parasite testing. The samples were tested at dilutions of 1:25, 1:50, and 1:100 against each parasite antigen by modified agglutination tests to determine whether antibodies to either parasite were present in the blood. Six of 62 samples (10%) were positive for T. gondii, with 2 samples having titers of 1:25 and 4 having titers of 1:50. Four of 62 samples (6%) were positive for S. neurona, with 2 samples having titers of 1:25 and 2 having titers of 1:50. ?? American Society of Pathologists 2005.

  18. Formation of agglutinate-like particles in an experimental regolith

    NASA Technical Reports Server (NTRS)

    See, Thomas H.; Horz, Friedrich

    1988-01-01

    Agglutinate-like particles composed predominantly of glass were produced from a fragmental gabbro target that was repetitively impacted by Ni-alloy projectiles. The experimental glasses are much more heterogeneous in composition than their lunar counterparts, and they are dominated by incomplete mixing of melted component minerals and by plagioclase-rich compositions. Most of the particles are found to be highly enriched in feldspar and to be sustantially fractionated relative to the initial bulk target. It is suggested that fractionation trends within lunar agglutinitic glasses may be partly due to phase-specific melting.

  19. Students' Attitudes toward Statistics (STATS).

    ERIC Educational Resources Information Center

    Sutarso, Toto

    The purposes of this study were to develop an instrument to measure students' attitude toward statistics (STATS), and to define the underlying dimensions that comprise the STATS. The instrument consists of 24 items. The sample included 79 male and 97 female students from the statistics classes at the College of Education and the College of…

  20. Seroprevalence Study of Human Brucellosis by Conventional Tests and Indigenous Indirect Enzyme-Linked Immunosorbent Assay

    PubMed Central

    Agasthya, Annapurna S.; Isloor, Srikrishna; Krishnamsetty, Prabhudas

    2012-01-01

    Brucellosis is one of the most important reemerging zoonoses in many countries. Brucellosis is caused by Gram-negative coccobacillus belonging to genus Brucella. Human brucellosis often makes the diagnosis difficult. The symptoms and clinical signs most commonly reported are fever, fatigue, malaise, chills, sweats headaches, myalgia, arthralgia, and weight loss. Some cases have been presented with only joint pain, lower backache, and involuntary limb movement, burning feet, or ischemic heart attacks. The focus of this work was to develop a highly sensitive and specific indirect ELISA by using smooth lipopolysaccharide antigen of Brucella abortus 99 to detect anti-Brucella antibodies at Project Directorate on Animal Disease Monitoring and Surveillance. Serum samples collected from 652 individuals in whom fever was not the major symptom but the complaint was of joint pain, headache, lower backache, and so forth, were screened by Rose Bengal plate agglutination test (RBPT) and standard tube agglutination test (STAT). Subsequent testing of sera by indigenous indirect ELISA detected 20 samples positive (3.6% seroprevalence), and indirect ELISA was found to be more sensitive than RBPT and STAT. The seroprevalence in South Karnataka was 2.14%, and in North Karnataka it was 0.92%. PMID:22566755

  1. Quantitative Determination of Fibrinogen of Patients with Coronary Heart Diseases through Piezoelectric Agglutination Sensor

    PubMed Central

    Chen, Qinghai; Hua, Xing; Fu, Weiling; Liu, Dongbo; Chen, Ming; Cai, Guoru

    2010-01-01

    Fibrinogen can transform fibrin through an agglutination reaction, finally forming fibrin polymer with grid structure. The density and viscosity of the reaction system changes drastically during the course of agglutination. In this research, we apply an independently-developed piezoelectric agglutination sensor to detect the fibrinogen agglutination reaction in patients with coronary heart diseases. The terminal judgment method of determining plasma agglutination reaction through piezoelectric agglutination sensor was established. In addition, the standard curve between plasma agglutination time and fibrinogen concentration was established to determinate fibrinogen content quantitatively. The results indicate the close correlation between the STAGO paramagnetic particle method and the method of piezoelectric agglutination sensor for the detection of Fibrinogen. The correlation coefficient was 0.91 (γ = 0.91). The determination can be completed within 10 minutes. The fibrinogen concentration in the coronary heart disease group was significantly higher than that of the healthy control group (P < 0.05). The results reveal that high fibrinogen concentration is closely correlated to the incurrence, development and prognosis of coronary heart diseases. Compared with other traditional methods, the method of piezoelectric agglutination sensor has some merits such as operation convenience, small size, low cost, quick detecting, good precision and the common reacting agents with paramagnetic particle method. PMID:22294917

  2. Vi-specific latex agglutination for early and rapid detection of Salmonella serotype typhi in blood cultures.

    PubMed

    Jesudason, M V; Sridharan, G; Mukundan, S; John, T J

    1994-02-01

    Latex particles coated with rabbit antisera against Salmonella serotype typhi (S. typhi) Vi and O (STO) antigens were used in slide agglutination tests for the rapid identification of S. typhi in blood culture broths as soon as Gram-negative bacilli (GNB) were detected in them. Among 231 consecutive blood cultures showing GNB tested for Vi, and a subset of 163 tested for STO, by latex agglutination (LA), 125 and 32, respectively, were positive. The GNB in 127 blood cultures were confirmed by conventional methods as S. typhi, 125 (98.4%) of which had been identified by the Vi LA test. In the subset of 163, 81 grew S. typhi, of which only 32 (39.5%) had been identified by the STO LA tests. Thus, the sensitivity of the Vi and STO LA tests was 98.4% and 39.5%, respectively, whereas the specificity was 100% for both tests. Of the S. typhi isolates, 38 (30.4%) were detected by the Vi LA test on day 2 and 73 (58.4%) on day 3, day 1 being the date of inoculation of the blood culture broths. Thus, the Vi LA test is suitable for the early and rapid confirmation of S. typhi in blood culture. PMID:7520382

  3. An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of sodium and potassium feldspars

    NASA Astrophysics Data System (ADS)

    Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

    1985-11-01

    The results of an experiment designed to test the validity of the model for agglutinate formation involving fusion of the finest fraction or F3 are reported. Impact glasses were formed from various mixes of orthoclase and albite powders, which were used as analogs for soils with chemically constrasting coarse and fine fractions. The results showed that the single most important factor displacing the composition of a small-scale impact melt from the bulk composition of the source regolith is the fractionated composition of the finest soil fraction. Volatile loss and the amount of melting, which in turn are determined by the degree of shock, are also important. As predicted by the model, the lower pressure melts are the most fractionated, and higher pressure is accompanied by increased melting causing glass compositions to approach the bulk. In general, the systematics predicted by the model are observed; the model appears to be valid.

  4. An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of sodium and potassium feldspars

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

    1985-01-01

    The results of an experiment designed to test the validity of the model for agglutinate formation involving fusion of the finest fraction or F3 are reported. Impact glasses were formed from various mixes of orthoclase and albite powders, which were used as analogs for soils with chemically constrasting coarse and fine fractions. The results showed that the single most important factor displacing the composition of a small-scale impact melt from the bulk composition of the source regolith is the fractionated composition of the finest soil fraction. Volatile loss and the amount of melting, which in turn are determined by the degree of shock, are also important. As predicted by the model, the lower pressure melts are the most fractionated, and higher pressure is accompanied by increased melting causing glass compositions to approach the bulk. In general, the systematics predicted by the model are observed; the model appears to be valid.

  5. Relationship between cell-bound dextransucrase and the agglutination of Streptococcus mutans.

    PubMed

    McCabe, M M; Smith, E E

    1975-09-01

    Dextran-induced agglutination of Streptococcus mutans cells is independent of cell-bound dextransucrase activity. Toluene extraction or the presence of Hg2+ or Cu2+ markedly decreased or completely abolished cell-bound dextransucrase activity without adversely affecting dextran-induced cell agglutination. Cells treated by heating at 100 C until cell-bound dextransucrase was completely inactivated continued to agglutinate when induced by dextran-induced cell agglutination resulted from cell treatment with trypsin and several other enzymes, as well as from ethylenediaminetetraacetic acid treatment, without a corresponding loss of cell-bound dextransucrase activity. Cells possessed a greater avidity for branched dextrans of low molecular weight than for linear dextrans of the same weight, indicating that size alone does not determine the efficiency of dextran as an inducer of agglutination. Divalent metal ions were required for both sucrose- and dextran-induced agglutination of S. mutans K1-R cells. Although normal cells of strain 6715-49 did not appear to require divalent cations for agglutination, heat- and ethlyenediaminetetraacetic acid-treated cells specifically required Ca2+. The role of Ca2+ in cell agglutination may be either to activate the cell-surface dextran receptor or to form specific intercellular Ca2+ bridges. PMID:809356

  6. An early Cambrian agglutinated tubular lophophorate with brachiopod characters

    PubMed Central

    Zhang, Z.-F.; Li, G.-X.; Holmer, L. E.; Brock, G. A.; Balthasar, U.; Skovsted, C. B.; Fu, D.-J.; Zhang, X.-L.; Wang, H.-Z.; Butler, A.; Zhang, Z.-L.; Cao, C.-Q.; Han, J.; Liu, J.-N.; Shu, D.-G.

    2014-01-01

    The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen. et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagerstätte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long pedicle with coelomic space. The terminal bulb of the pedicle provided anchorage in soft sediment. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods. PMID:24828016

  7. Eriocalyxin B Inhibits STAT3 Signaling by Covalently Targeting STAT3 and Blocking Phosphorylation and Activation of STAT3.

    PubMed

    Yu, Xiaokui; He, Li; Cao, Peng; Yu, Qiang

    2015-01-01

    Activated STAT3 plays an important role in oncogenesis by stimulating cell proliferation and resisting apoptosis. STAT3 therefore is an attractive target for cancer therapy. We have screened a traditional Chinese herb medicine compound library and found Eriocalyxin B (EB), a diterpenoid from Isodon eriocalyx, as a specific inhibitor of STAT3. EB selectively inhibited constitutive as well as IL-6-induced phosphorylation of STAT3 and induced apoptosis of STAT3-dependent tumor cells. EB did not affect the upstream protein tyrosine kinases or the phosphatase (PTPase) of STAT3, but rather interacted directly with STAT3. The effects of EB could be abolished by DTT or GSH, suggesting a thiol-mediated covalent linkage between EB and STAT3. Site mutagenesis of cysteine in and near the SH2 domain of STAT3 identified Cys712 to be the critical amino acid for the EB-induced inactivation of STAT3. Furthermore, LC/MS/MS analyses demonstrated that an α, β-unsaturated carbonyl of EB covalently interacted with the Cys712 of STAT3. Computational modeling analyses also supported a direct interaction between EB and the Cys712 of STAT3. These data strongly suggest that EB directly targets STAT3 through a covalent linkage to inhibit the phosphorylation and activation of STAT3 and induces apoptosis of STAT3-dependent tumor cells. PMID:26010889

  8. Eriocalyxin B Inhibits STAT3 Signaling by Covalently Targeting STAT3 and Blocking Phosphorylation and Activation of STAT3

    PubMed Central

    Yu, Xiaokui; He, Li; Cao, Peng; Yu, Qiang

    2015-01-01

    Activated STAT3 plays an important role in oncogenesis by stimulating cell proliferation and resisting apoptosis. STAT3 therefore is an attractive target for cancer therapy. We have screened a traditional Chinese herb medicine compound library and found Eriocalyxin B (EB), a diterpenoid from Isodon eriocalyx, as a specific inhibitor of STAT3. EB selectively inhibited constitutive as well as IL-6-induced phosphorylation of STAT3 and induced apoptosis of STAT3-dependent tumor cells. EB did not affect the upstream protein tyrosine kinases or the phosphatase (PTPase) of STAT3, but rather interacted directly with STAT3. The effects of EB could be abolished by DTT or GSH, suggesting a thiol-mediated covalent linkage between EB and STAT3. Site mutagenesis of cysteine in and near the SH2 domain of STAT3 identified Cys712 to be the critical amino acid for the EB-induced inactivation of STAT3. Furthermore, LC/MS/MS analyses demonstrated that an α, β-unsaturated carbonyl of EB covalently interacted with the Cys712 of STAT3. Computational modeling analyses also supported a direct interaction between EB and the Cys712 of STAT3. These data strongly suggest that EB directly targets STAT3 through a covalent linkage to inhibit the phosphorylation and activation of STAT3 and induces apoptosis of STAT3-dependent tumor cells. PMID:26010889

  9. Agglutination of Sindbis Virus and of Cells Infected with Sindbis Virus by Plant Lectins

    PubMed Central

    Birdwell, Charles R.; Strauss, James H.

    1973-01-01

    We have examined the agglutination of Sindbis virus and of chick and hamster cells infected with Sindbis virus by two of the plant lectins, concanavalin A and Ricinus communis agglutinin. Both lectins agglutinate the virus by binding to the polysaccharide chains of the envelope glycoproteins. Both chick and hamster cells exhibit increased agglutination by the lectins after infection by Sindbis virus. In the case of chick cells infected with Sindbis virus, this increase in agglutinability occurs between 3 and 5 h after infection. Infected and mock-infected cells bind the same amount of 3H-labeled concanavalin A, which suggests that the increase in agglutination after infection is due to rearrangements at the cell surface rather than to insertion of new lectin binding sites per se. PMID:4735591

  10. Utility of Serological Tests in the Era of Molecular Testing for Diagnosis of Human Brucellosis in Endemic Area with Limited Resources

    PubMed Central

    Metgud, Sharada C.; Mutnal, Manohar B; Nagamoti, Mahantesh B; Patil, Chidanand S.

    2016-01-01

    Background The culture has always been the gold standard test for diagnosis of human brucellosis but the conventional Brucella diagnostic tests viz. serology and culture are often beset with poor specificity & sensitivity respectively. The culture positivity rates for Brucella vary from 92% for bone marrow to 10% for non-blood samples and also dependent on the type of sample. The primary immune-determinant for Brucella species is the cell wall surface lipopolysaccharide, which is antigenically similar to other gram-negative rods. Hence, Brucella serological tests cross react with Escherichia coli 0116 and 0157, Salmonella urbana, Yersinia enterocolitica 0:9, Vibrio cholerae, Xanthomonas maltophilia and Afipia clevellandensis infections, which are common in developing countries also having higher incidence of brucellosis. Aim The aim of the study was evaluation of conventional serological techniques and PCR for diagnosis of human brucellosis in and around north Karnataka which is endemic for brucellosis and patients often present with elevated base line antibody titers and confounding clinical manifestations. Materials and Methods Blood/serum samples of 400 patients suffering from acute undifferentiated fever (AUF) were subjected to culture, Brucella slide agglutination test (SAT), standard tube agglutination test (STAT coupled with 2 ME) and PCR. Results Of the 400 AUF patients, anti-Brucella antibodies were detected by SAT and STAT in serum of 35 and 34 patients respectively. IS711 gene for Brucella was identified in 32 patients by PCR. Twenty samples yielded Brucella in culture on biphasic medium with average incubation period of 9 days. All patients having titer of ≥ 160IU / ml in STAT were found positive by PCR also. Conclusion Brucella STAT corroborated well with PCR results in all those cases where antibodies were present at least one dilution above cut-off value of 80 IU/ml. We probably need to raise cut-off titers to ≥160 IU/ml because of endemic region

  11. Identification of Haemophilus influenzae Serotypes by Standard Slide Agglutination Serotyping and PCR-Based Capsule Typing

    PubMed Central

    LaClaire, Leslye L.; Tondella, Maria Lucia C.; Beall, David S.; Noble, Corie A.; Raghunathan, Pratima L.; Rosenstein, Nancy E.; Popovic, Tanja

    2003-01-01

    To resolve discrepancies in slide agglutination serotyping (SAST) results from state health departments and the Centers for Disease Control and Prevention (CDC), we characterized 141 of 751 invasive Haemophilus influenzae isolates that were identified in the United States from January 1998 to December 1999 through an active, laboratory-based, surveillance program coordinated by the CDC. We found discrepancies between the results of SAST performed at state health departments and those of PCR capsule typing performed at the CDC for 56 (40%) of the isolates characterized: 54 isolates that were identified as a particular serotype by SAST were shown to be unencapsulated by PCR, and two isolates that were reported as serotypes b and f were found to be serotypes f and e, respectively, by PCR. The laboratory error most likely to affect the perceived efficacy of the conjugate H. influenzae type b (Hib) vaccine was the misidentification of isolates as serotype b: of 40 isolates identified as serotype b by SAST, 27 (68%) did not contain the correlating capsule type genes. The frequency of errors fell substantially when standardized reagents and routine quality control of SAST were used during a study involving three laboratories. An overall 94% agreement between SAST and PCR results showed that slide agglutination could be a valid and reliable method for serotyping H. influenzae if the test was performed correctly, in accordance with standardized and recommended procedures. An ongoing prospective analysis of all H. influenzae surveillance isolates associated with invasive disease in children less than 5 years old will provide more accurate national figures for the burden of invasive disease caused by Hib and other H. influenzae serotypes. PMID:12517878

  12. Red blood cell membrane viscoelasticity, agglutination and zeta potential measurements with double optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Fernandes, Heloise P.; Barjas-Castro, Maria L.; de Thomaz, André A.; de Ysasa Pozzo, Liliana; Barbosa, Luiz C.; Cesar, Carlos L.

    2006-02-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycolproteins embedded in, or attached, to a fluid lipid bilayer and are negatively charged, which creates a repulsive electric (zeta) potential between the cells and prevents their aggregation in the blood stream. There are techniques, however, to decrease the zeta potential to allow cell agglutination which are the basis of most of the tests of antigen-antibody interactions in blood banks. This report shows the use of a double optical tweezers to measure RBC membrane viscosity, agglutination and zeta potential. In our technique one of the optical tweezers trap a silica bead that binds strongly to a RBC at the end of a RBCs rouleaux and, at the same time, acts as a pico-Newton force transducer, after calibration through its displacement from the equilibrium position. The other optical tweezers trap the RBC at the other end. To measure the membrane viscosity the optical force is measured as a function of the velocity between the RBCs. To measure the adhesion the tweezers are slowly displaced apart until the RBCs disagglutination happens. The RBC zeta potential is measured in two complimentary ways, by the force on the silica bead attached to a single RBC in response to an applied electric field, and the conventional way, by the measurement of terminal velocity of the RBC after released from the optical trap. These two measurements provide information about the RBC charges and, also, electrolytic solution properties. We believe this can improve the methods of diagnosis in blood banks.

  13. Active components with inhibitory activities on IFN-γ/STAT1 and IL-6/STAT3 signaling pathways from Caulis Trachelospermi.

    PubMed

    Liu, Xiao-Ting; Wang, Zhe-Xing; Yang, Yu; Wang, Lin; Sun, Ruo-Feng; Zhao, Yi-Min; Yu, Neng-Jiang

    2014-01-01

    Initial investigation for new active herbal extract with inhibiting activity on JAK/STAT signaling pathway revealed that the extract of Caulis Trachelospermi, which was separated by 80% alcohol extraction and subsequent HP-20 macroporous resin column chromatography, was founded to strongly inhibit IFN-γ-induced STAT1-responsive luciferase activity (IFN-γ/STAT1) with IC50 value of 2.43 μg/mL as well as inhibiting IL-6-induced STAT3-responsive luciferase activity (IL-6/STAT3) with IC50 value of 1.38 μg/mL. Subsequent study on its active components led to the isolation and identification of two new dibenzylbutyrolactone lignans named 4-demethyltraxillaside (1) and nortrachelogenin 4-O-β-D-glucopyranoside (2), together with six known compounds. The lignan compounds 1-4 together with other lignan compounds isolated in previous study were tested the activities on IFN-γ/STAT1 and IL-6/STAT3 pathways. The following result showed that the main components trachelogenin and arctigenin had corresponding activities on IFN-γ/STAT1 pathway with IC50 values of 3.14 μM and 9.46 μM as well as trachelogenin, arctigenin and matairesinol strongly inhibiting IL-6/STAT3 pathway with IC50 values of 3.63 μM, 6.47 μM and 2.92 μM, respectively. PMID:25100250

  14. STAT1 and STAT3 do not participate in FGF-mediated growth arrest in chondrocytes.

    PubMed

    Krejci, Pavel; Salazar, Lisa; Goodridge, Helen S; Kashiwada, Tamara A; Schibler, Matthew J; Jelinkova, Petra; Thompson, Leslie Michels; Wilcox, William R

    2008-02-01

    Activating mutations in fibroblast growth factor receptor 3 (FGFR3) cause several human skeletal dysplasias as a result of attenuation of cartilage growth. It is believed that FGFR3 inhibits chondrocyte proliferation via activation of signal transducers and activators of transcription (STAT) proteins, although the exact mechanism of both STAT activation and STAT-mediated inhibition of chondrocyte growth is unclear. We show that FGFR3 interacts with STAT1 in cells and is capable of activating phosphorylation of STAT1 in a kinase assay, thus potentially serving as a STAT1 kinase in chondrocytes. However, as demonstrated by western blotting with phosphorylation-specific antibodies, imaging of STAT nuclear translocation, STAT transcription factor assays and STAT luciferase reporter assays, FGF does not activate STAT1 or STAT3 in RCS chondrocytes, which nevertheless respond to a FGF stimulus with potent growth arrest. Moreover, addition of active STAT1 and STAT3 to the FGF signal, by means of cytokine treatment, SRC-mediated STAT activation or expression of constitutively active STAT mutants does not sensitize RCS chondrocytes to FGF-mediated growth arrest. Since FGF-mediated growth arrest is rescued by siRNA-mediated downregulation of the MAP kinase ERK1/2 but not STAT1 or STAT3, our data support a model whereby the ERK arm but not STAT arm of FGF signaling in chondrocytes accounts for the growth arrest phenotype. PMID:18198189

  15. Identification, gene expression and immune function of the novel Bm-STAT gene in virus-infected Bombyx mori.

    PubMed

    Zhang, Xiaoli; Guo, Rui; Kumar, Dhiraj; Ma, Huanyan; Liu, Jiabin; Hu, Xiaolong; Cao, Guangli; Xue, Renyu; Gong, Chengliang

    2016-02-10

    Genes in the signal transducer and activator of transcription (STAT) family are vital for activities including gene expression and immune response. To investigate the functions of the silkworm Bombyx mori STAT (Bm-STAT) gene in antiviral immunity, two Bm-STAT gene isoforms, Bm-STAT-L for long form and Bm-STAT-S for short form, were cloned. Sequencing showed that the open reading frames were 2313 bp encoding 770 amino acid residues for Bm-STAT-L and 2202 bp encoding 734 amino acid residues for Bm-STAT-S. The C-terminal 42 amino acid residues of Bm-STAT-L were different from the last 7 amino acid residues of Bm-STAT-S. Immunofluorescence showed that Bm-STAT was primarily distributed in the nucleus. Transcription levels of Bm-STAT in different tissues were determined by quantitative PCR, and the results revealed Bm-STAT was mainly expressed in testes. Western blots showed two bands with molecular weights of 70 kDa and 130 kDa in testes, but no bands were detected in ovaries by using anti-Bm-STAT antibody as the primary antibody. Expression of Bm-STAT in hemolymph at 48 h post infection with B. mori macula-like virus (BmMLV) was slightly enhanced compared with controls, suggesting a weak response induced by infection with BmMLV. Hemocyte immunofluorescence showed that Bm-STAT expression was elevated in B. mori nucleopolyhedrovirus (BmNPV)-infected cells. Moreover, resistance of BmN cells to BmNPV was reduced by downregulation of Bm-STAT expression and increased by upregulation. Resistance of BmN cells to BmCPV was not significantly improved by upregulating Bm-STAT expression. Therefore, we concluded that Bm-STAT is a newly identified insect gene of the STAT family. The JAK-STAT pathway has a more specialized role in antiviral defense in silkworms, but JAK-STAT pathway is not triggered in response to all viruses. PMID:26592694

  16. Agglutinating activity of alcohol-soluble proteins from quinoa seed flour in celiac disease.

    PubMed

    De Vincenzi, M; Silano, M; Luchetti, R; Carratù, B; Boniglia, C; Pogna, N E

    1999-01-01

    The edible seeds of the quinoa plant contain small quantities of alcohol-soluble protein which, after peptic-tryptic digestion, are unable to agglutinate K562(s) cells. When separated by affinity chromatography on sepharose-6B coupled with mannan, peptic-tryptic digest separated in two fractions. Fraction B peptides (about 1% of total protein) were shown to agglutinate K562(s) cells at a very low concentration, whereas peptides in fraction A and in the mixed fraction A+B were inactive, suggesting that fraction A contains protective peptides that interfere with the agglutinating activity of toxic peptides in fraction B. PMID:10646556

  17. Momordica charantia seed lectin: toxicity, bacterial agglutination and antitumor properties.

    PubMed

    Kabir, Syed Rashel; Nabi, Md Mahamodun; Nurujjaman, Md; Abu Reza, Md; Alam, A H M Khurshid; Uz Zaman, Rokon; Khalid-Bin-Ferdaus, Khandaker Md; Amin, Ruhul; Khan, Md Masudul Hasan; Hossain, Md Anowar; Uddin, Md Salim; Mahmud, Zahid Hayat

    2015-03-01

    In last three decades, several studies were carried out on the D-galactose-specific lectin of Momordica charantia seeds (MCL). In the present study, in vitro growth inhibition (8-23 %) at different concentrations (6-24 μg/ml) of MCL was observed against Ehrlich ascites carcinoma (EAC) cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MCL also showed 28, 45, and 75 % growth inhibitions against EAC cells when administered 1.2, 2.0, and 2.8 mg/kg/day (i.p.), respectively for five consequent days in vivo in mice. After lectin treatment, the level of red blood cell and hemoglobin was increased significantly with the decrease of white blood cell and maintained the normal level when compared with EAC-bearing control and normal mice without EAC cells. Although MCL caused cell cycle arrest at G0/G1 phase of EAC cells, any irregular shape or apoptotic morphological alterations in the lectin-treated EAC cells was not observed by an optical and fluorescence microscope. Lectin showed toxicity against brine shrimp nauplii with an LC50 value of 49.7 μg/ml. Four out of seven pathogenic bacteria were agglutinated by MCL in the absence of inhibitory sugar D-lactose/D-galactose. In conclusion, MCL showed strong cytotoxic effect and therefore can be used as a potent anticancer chemotherapeutic agent. PMID:25542240

  18. Commensal symbiosis between agglutinated polychaetes and sulfate-reducing bacteria.

    PubMed

    Guido, A; Mastandrea, A; Rosso, A; Sanfilippo, R; Tosti, F; Riding, R; Russo, F

    2014-05-01

    Pendant bioconstructions occur within submerged caves in the Plemmirio Marine Protected Area in SE Sicily, Italy. These rigid structures, here termed biostalactites, were synsedimentarily lithified by clotted-peloidal microbial carbonate that has a high bacterial lipid biomarker content with abundant compounds derived from sulfate-reducing bacteria. The main framework builders are polychaete serpulid worms, mainly Protula with subordinate Semivermilia and Josephella. These polychaetes have lamellar and/or fibrillar wall structure. In contrast, small agglutinated terebellid tubes, which are a minor component of the biostalactites, are discontinuous and irregular with a peloidal micritic microfabric. The peloids, formed by bacterial sulfate reduction, appear to have been utilized by terebellids to construct tubes in an environment where other particulate sediment is scarce. We suggest that the bacteria obtained food from the worms in the form of fecal material and/or from the decaying tissue of surrounding organisms and that the worms obtained peloidal micrite with which to construct their tubes, either as grains and/or as tube encompassing biofilm. Peloidal worm tubes have rarely been reported in the recent but closely resemble examples in the geological record that extend back at least to the early Carboniferous. This suggests a long-lived commensal relationship between some polychaete worms and heterotrophic, especially sulfate-reducing, bacteria. PMID:24636469

  19. STAT3 the oncogene - still eluding therapy?

    PubMed

    Wake, Matthew S; Watson, Christine J

    2015-07-01

    The STAT family of transcription factors (signal transducers and activators of transcription) transduce signals from cytokine receptors to the nucleus, where STAT dimers bind to DNA and regulate transcription. STAT3 is the most ubiquitous of the STATs, being activated by a wide variety of cytokines and growth factors. STAT3 has many roles in physiological processes such as inflammatory signalling, aerobic glycolysis and immune suppression, and was also the first family member shown to be aberrantly activated in a wide range of both solid and liquid tumours. STAT3 promotes tumorigenesis by regulating the expression of various target genes, including cell-cycle regulators, angiogenic factors and anti-apoptosis genes. Paradoxically, in some circumstances, STAT3 signalling induces cell death. The best known example is the involuting mammary gland, where STAT3 is essential for induction of a lysosomal pathway of cell death. Nevertheless, direct silencing or inhibition of STAT3 diminishes tumour growth and survival in both animal and human studies. This suggests that abolishing STAT3 activity may be an effective cancer therapeutic strategy. However, despite this potential as a therapeutic target, and the extensive attempts by many laboratories and pharmaceutical companies to develop an effective STAT3 inhibitor for use in the clinic, no direct STAT3 inhibitor has been approved for clinical use. In this review, we focus on the role of STAT3 in tumorigenesis, and discuss its potential as a therapeutic target for cancer treatment. PMID:25825152

  20. Passive immunization with Leptospira LPS-specific agglutinating but not non-agglutinating monoclonal antibodies protect guinea pigs from fatal pulmonary hemorrhages induced by serovar Copenhageni challenge.

    PubMed

    Challa, Sreerupa; Nally, Jarlath E; Jones, Carroll; Sheoran, Abhineet S

    2011-06-15

    Leptospira interrogans serovar Copenhageni causes pulmonary hemorrhages with respiratory failure, a major cause of death in leptospirosis patients. Protective immunity to Leptospira is known to correlate with the production of leptospiral lipopolysaccharide (L-LPS)-specific agglutinating antibodies. We generated L-LPS-specific mouse monoclonal antibodies (MAbs) and investigated if these MAbs can protect guinea pigs against fatal pulmonary hemorrhages caused by serovar Copenhageni. The MAbs L8H4 and L9B11 against 22kDa L-LPS agglutinated leptospires and completely protected guinea pigs from the development of fatal pulmonary hemorrhages by serovar Copenhageni, whereas the MAb L4C1 against 8kDa L-LPS neither agglutinated the bacteria nor protected the animals against the fatal pulmonary hemorrhages. PMID:21549788

  1. In vivo antitumor efficacy of STAT3 blockade using a transcription factor decoy approach: implications for cancer therapy.

    PubMed

    Xi, Sichuan; Gooding, William E; Grandis, Jennifer Rubin

    2005-02-01

    The development of more effective prevention and treatment strategies for solid tumors is limited by an incomplete understanding of the critical growth pathways that are activated in carcinogenesis. Signal transducers and activators of transcription (STAT) proteins have been linked to transformation and tumor progression. Several approaches have been used to block STAT3 in cancer cells resulting in reduced proliferation and apoptosis. We tested the hypothesis that blocking STAT3 activation using a transcription factor decoy approach would decrease tumor growth and STAT3 target gene expression in vivo. In a xenograft model of squamous cell carcinoma of the head and neck (SCCHN), daily administration of the STAT3 decoy (25 microg) resulted in decreased tumor volumes, abrogation of STAT3 activation, and decreased expression of STAT3 target genes (VEGF, Bcl-xL, and cyclin D1) compared to treatment with a mutant control decoy. Blockade of STAT3 with the STAT3 decoy also induced apoptosis and decreased proliferation, an effect that was augmented when the STAT3 decoy was combined with cisplatin, both in vitro and in vivo. These results suggest that a transcription factor decoy approach may be used to target STAT3 in cancers that demonstrate increased STAT3 activation including SCCHN. PMID:15592503

  2. The Cenozoic Diversity of Agglutinated Foraminifera - Evidence for a late Oligocene to early Miocene diversification event

    NASA Astrophysics Data System (ADS)

    Kaminski, Michael; Setoyama, Eiichi; Kender, Sev; Cetean, Claudia

    2014-05-01

    The agglutinated foraminifera are among the most abundant micro-organisms in the deep marine environment and have a diversity record extending back to the late Precambrian. We present an updated diversity curve for agglutinated foraminiferal genera based on the stratigraphic ranges of all the agglutinated genera recognized as valid in the classification of Kaminski (2014). The data set for this analysis is based on the stratigraphic ranges of agglutinated genera published in Foraminiferal Genera and their Classification, which has been subsequently updated based on published studies and our new observations. The mean standing diversity of agglutinated foraminiferal genera was compiled by counting the number of boundary crossers rather than the number of genera in each stage. In this study, we report the stratigraphic and geographical occurrence of a benthic foraminiferal diversification event that has previously received little attention. In the latest Oligocene to earliest Miocene a number of trochospiral agglutinated genera with alveolar or canaliculate walls first appeared in the fossil record. Our studies of late Oligocene of the Congo fan, offshore Angola (Kender et al., 2008; Cetean and Kaminski, 2011) have revealed a diverse assemblage that includes new taxa of deep-water agglutinated foraminifera. In a biostratigraphic study of the Miocene foraminiferal assemblages Kender et al. (2008) noted steadily increasing diversity and proportions of infaunal agglutinated foraminiferal morphotypes over the lower Miocene interval. The proportion of infaunal agglutinated foraminifera assigned to the order Textularida increased dramatically in the lower mid-Miocene, suggesting expansion of the oxygen minimum zone into deeper waters. In addition to the trochospiral alveolar genera, several species of Reticulophragmium and Cyclammina display rapid diversification into numerous separate lineages that are at present not reflected in our generic diversity record owing to

  3. PeriStats: Perinatal Statistics

    MedlinePlus

    ... is developed by the March of Dimes Perinatal Data Center and provides access to maternal and infant health ... on PeriStats sometimes different from my health department's data? What should I do if pop-up blocker ... We acknowledge the Centers for Disease Control and Prevention for its support ...

  4. The role of stat1b in zebrafish hematopoiesis

    PubMed Central

    Song, Hao; Yan, Yi-lin; Titus, Tom; He, Xinjun; Postlethwait, John H.

    2011-01-01

    STAT1 mediates response to interferons and regulates immunity, cell proliferation, apoptosis, and sensitivity of Fanconi Anemia cells to apoptosis after interferon signaling; the roles of STAT1 in embryos, however, are not understood. To explore embryonic functions of STAT1, we investigated stat1b, an unstudied zebrafish co-ortholog of human STAT1. Zebrafish stat1a encodes all five domains of the human STAT1-alpha splice form but, like the human STAT1-beta splice variant, stat1b lacks a complete transactivation domain; thus, two unlinked zebrafish paralogs encode protein forms translated from two splice variants of a single human gene, as expected by subfunctionalization after genome duplication. Phylogenetic and conserved synteny studies showed that stat1b and stat1a arose as duplicates in the teleost genome duplication (TGD) and clarified the evolutionary origin of STAT1, STAT2, STAT3, STAT4, STAT5A, STAT5B and STAT6 by tandem and genome duplication. RT-PCR revealed maternal expression of stat1a and stat1b. In situ hybridization detected stat1b but not stat1a expression in embryonic hematopoietic tissues. Morpholino knockdown of stat1b, but not stat1a, decreased expression of the myeloid and granulocyte markers spi and mpo and increased expression of the hematopoietic progenitor marker scl, the erythrocyte marker gata1, and hemoglobin. These results suggest that zebrafish Stat1b promotes myeloid development at the expense of erythroid development. PMID:21914475

  5. Small molecules, LLL12 and FLLL32, inhibit STAT3 and exhibit potent growth suppressive activity in osteosarcoma cells and tumor growth in mice.

    PubMed

    Onimoe, Grace-Ifeyinwa; Liu, Aiguo; Lin, Li; Wei, Chang-Ching; Schwartz, Eric B; Bhasin, Deepak; Li, Chenglong; Fuchs, James R; Li, Pui-kai; Houghton, Peter; Termuhlen, Amanda; Gross, Thomas; Lin, Jiayuh

    2012-06-01

    Constitutive activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in osteosarcoma, and hence, may serve as a therapeutic target. In order to target STAT3, we tested two new STAT3 inhibitors, LLL12 and FLLL32. LLL12 and FLLL32 inhibit STAT3 phosphorylation and STAT3 downstream targets. LLL12 and FLLL32 also inhibit IL-6 induced STAT3 phosphorylation. The inhibition of STAT3 by LLL12 and FLLL32 resulted in the induction of apoptosis, reduction of plating efficiency, and migration in osteosarcoma cells. Furthermore, LLL12 and FLLL32 inhibited SJSA osteosarcoma cells and OS-33 tumor growth in murine xenografts. These results provide evidence that constitutive STAT3 signaling is required for osteosarcoma survival and migration in vitro and tumor growth in vivo. Blocking persistent STAT3 signaling by LLL12 and FLLL32 may be a novel therapeutic approach for osteosarcoma. PMID:21340507

  6. Modulation of ligand-mediated human red cell agglutinability by prostaglandins

    SciTech Connect

    McLawhon, R.W.; Marikovsky, Y.; Weinstein, R.S.

    1986-03-01

    Ethanol induces the transformation of human red cells from bioconcave discs to echinocytes in vitro. In addition, they have observed that ethanol can enhance the agglutination of red cells by the plant lectin wheat germ agglutinin or poly-L-lysine. Incubation of washed human red cells with 5 and 10% ethanol (v/v) in phosphate buffered saline, pH 7.3 at 25/sup 0/C produced a 30% increase in ligand-mediated agglutinability within 12 min. Simultaneous addition of ethanol and one of the following prostaglandin derivatives, PGE/sub 1/, pge/sub 2/, pgf/sub 2/-alpha, or PGl/sub 2/ (10/sup -9/ to 5 x 10/sup -7/ M) prevented the shape-associated increases in red cell agglutinability. Thromboxane-B/sub 2/ had no effect on agglutinability. Prostaglandins did not prevent ethanol-induced red cell shape transformations per se under identical experimental conditions. As intragastric administration of 100% ethanol results in the formation of spiculated red cell thrombi in postcapillary venules of rat gastric mucosa, they postulate that the cytoprotective role of prostanoids in preventing mucosal ulceration may be due in part to their capacity to inhibit intravascular ligand mediated red cell agglutination, hemostasis, and their sequelae, epithelial necrosis. Moreover, the data suggest that ethanol-induced red cell shape transformations and ligand-mediated agglutination represent two distinct and independent biological phenomena.

  7. [Detection of anti-Brucella spp. antibodies in swine by agglutination techniques and indirect ELISA in the Buenos Aires and La Pampa provinces, Argentina].

    PubMed

    Castro, H A; González, S R; Prat, M I; Baldi, P C

    2006-01-01

    Porcine brucellosis is one of the most important zoonoses in this country. Currently, there is no control program for porcine brucellosis in Argentina and the epidemiological situation is still unknown. The purpose of our study was to detect anti-Brucella spp. antibodies in swine in the southwest of the Buenos Aires province and the east of the La Pampa province. Blood samples were obtained when animals were slaughtered. The presence of anti-brucella antibodies was studied by the buffered plate agglutination test (BPA), the tube agglutination test (SAT), the 2-mercaptoethanol (2-ME) agglutination test and indirect ELISA tests, using the cytosolic fraction from Brucella abortus S19 (CYT), and lipopolysaccharide (LPS)-free cytosolic proteins (CP). Out of a total of 325 samples analyzed, 17.8% reacted positively to BPA, 13.8% to SAT, 8.0% to 2-ME, 21.0% to ELISA-CYT and 10.0% to ELISA-CP. These results agree with the few data available in our country and suggest that brucellosis screening should be extended to other regions. PMID:17037254

  8. Seroprevalence of human brucellosis in and around Jammu, India, using different serological tests

    PubMed Central

    Sharma, H. K.; Kotwal, S. K.; Singh, D. K.; Malik, M. A.; Kumar, Arvind; Rajagunalan; Singh, M.

    2016-01-01

    Aim: Brucellosis is a disease of zoonotic importance as it affects both human as well as animal’s health, and therefore, directly affects animal productivity and human efficiency. Therefore, a study was conducted to estimate the seroprevalence of brucellosis in humans in Jammu and surrounding areas. Materials and Methods: A total of 121 sera samples from humans occupied with professional related to animals were collected and tested for anti-Brucella antibodies by Rose Bengal plate test (RBPT), modified RBPT (mRBPT), standard tube agglutination test (STAT), and indirect enzyme-linked immunosorbent assay (I-ELISA). Sampling was done keeping in view with the occupation, sex, and age. Results: The overall seroprevalence of brucellosis recorded was 4.96%. The test-wise seroprevalence was 9.91% by RBPT, 9.91% by mRBPT, 9.09% by STAT, and 16.52% by I-ELISA. The prevalence of brucellosis was higher in >35-50 years age group compared to >20-35 years and >50-65 years. Sex-wise seroprevalence was higher in males than females. Taking I-ELISA as standard, the relative sensitivities of mRBPT, RBPT, and I-ELISA were in the order of mRBPT=RBPT>STAT. All the tests revealed high specificity values; however, among different serological tests, I-ELISA detected a maximum number of positive sera samples. Conclusions: The prevalence of brucellosis was found to be approximately 5%. The adult (>35-50 years) age male group was most vulnerable. The routine diagnosis of brucellosis involved the conventional serological tests, viz., RBPT and STAT, but each was associated with drawbacks which could give either false-positive or false-negative interpretation. Therefore, it is always recommended to use a battery of tests in the diagnosis of brucellosis. PMID:27536036

  9. Activating STAT6 mutations in follicular lymphoma

    PubMed Central

    Yildiz, Mehmet; Li, Hongxiu; Bernard, Denzil; Amin, Nisar A.; Ouillette, Peter; Jones, Siân; Saiya-Cork, Kamlai; Parkin, Brian; Jacobi, Kathryn; Shedden, Kerby; Wang, Shaomeng; Chang, Alfred E.; Kaminski, Mark S.

    2015-01-01

    Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma in the Western world. FL cell-intrinsic and cell-extrinsic factors influence FL biology and clinical outcome. To further our understanding of the genetic basis of FL, we performed whole-exome sequencing of 23 highly purified FL cases and 1 transformed FL case and expanded findings to a combined total of 114 FLs. We report recurrent mutations in the transcription factor STAT6 in 11% of FLs and identified the STAT6 amino acid residue 419 as a novel STAT6 mutation hotspot (p.419D/G, p.419D/A, and p.419D/H). FL-associated STAT6 mutations were activating, as evidenced by increased transactivation in HEK293T cell–based transfection/luciferase reporter assays, heightened interleukin-4 (IL-4) –induced activation of target genes in stable STAT6 transfected lymphoma cell lines, and elevated baseline expression levels of STAT6 target genes in primary FL B cells harboring mutant STAT6. Mechanistically, FL-associated STAT6 mutations facilitated nuclear residency of STAT6, independent of IL-4–induced STAT6-Y641 phosphorylation. Structural modeling of STAT6 based on the structure of the STAT1-DNA complex revealed that most FL-associated STAT6 mutants locate to the STAT6-DNA interface, potentially facilitating heightened interactions. The genetic and functional data combined strengthen the recognition of the IL-4/JAK/STAT6 axis as a driver of FL pathogenesis. PMID:25428220

  10. Advances in peptidic and peptidomimetic-based approaches to inhibit STAT signaling in human diseases.

    PubMed

    Szelag, Malgorzata; Wesoly, Joanna; Bluyssen, Hans A R

    2016-01-01

    STATs promote fundamental cellular processes, marking them as convergence points of many oncogenic and inflammatory pathways. Therefore, aberrant activation of STAT signaling is implicated in a plethora of human diseases, like cancer, inflammation and auto-immunity. Identification of STAT-specific inhibitors is the topic of great practical importance, and various inhibitory strategies are being pursued. An interesting approach includes peptides and peptide-like biopolymers, because they allow the manipulation of STAT signaling without the transfer of genetic material. Phosphopeptides and peptidomimetics directly target STATs by inhibiting dimerization. Despite that a large number of efficient peptide- based STAT3-specific inhibitors have been reported to date, none of them was able to meet the pharmacological requirements to serve as a potent anti-cancer drug. The existing limitations, like metabolic instability and poor cell permeability during in vivo tests, excluded these macromolecules from further clinical development. To overcome these liabilities, in the last five years many advances have been made to develop next generation STAT-specific inhibitors. Here we discuss the pitfalls of current STAT inhibitory strategies and review the progress on the development of peptide-like prodrugs directly targeting STATs. Novel strategies involve screening of high-complexity libraries of random peptides, as specific STAT3 or STAT5 DNA-binding inhibitors, to construct cell permeable peptide aptamers and aptides for cancer therapy. Another new direction is synthesis of negative dominant α-helical mimetics of the STAT3 N-domain, preventing oligomerization on DNA. Moreover, construction of phosphopeptide conjugates with molecules mediating cellular uptake offers new therapeutic possibilities in treatment of cancer, asthma and allergy. PMID:26521960

  11. Cucurbitacin B and cucurbitacin I suppress adipocyte differentiation through inhibition of STAT3 signaling.

    PubMed

    Seo, Cho-Rong; Yang, Dong Kwon; Song, No-Joon; Yun, Ui Jeong; Gwon, A-Ryeong; Jo, Dong-Gyu; Cho, Jae Youl; Yoon, Keejung; Ahn, Jee-Yin; Nho, Chu Won; Park, Woo Jin; Yang, Seung Yul; Park, Kye Won

    2014-02-01

    Cucurbitacin B, a member of the cucurbitaceae family, can act as a STAT3 signaling inhibitor to regulate the growth of hepatocellular carcinoma. STAT3 signaling has been shown to inhibit adipocyte differentiation through C/EBPα and PPARγ. Based on these studies, we hypothesized that cucurbitacin B would prevent PPARγ mediated adipocyte differentiation through STAT3 signaling. To test this hypothesis, mesenchymal C3H10T1/2 and 3T3-L1 preadipocyte cells were treated with a sub-cytotoxic concentration of cucurbitacin B. Cucurbitacin B treatment inhibits lipid accumulation and expression of adipocyte markers including PPARγ and its target genes in a dose-dependent manner. Cucurbitacin B treatment impairs STAT3 signaling as manifested by reduced phosphorylation of STAT3 and suppression of STAT3 target gene expression in preadipocytes. The anti-adipogenic effects of cucurbitacin B are significantly blunted in cells with STAT3 silenced by introducing small interfering RNA. Finally, our data show that cucurbitacin I, another cucurbitacin family member, also inhibits adipocyte differentiation by suppressing STAT3 signaling. Together, our data suggest the possibility of utilizing cucurbitacins as a new strategy to treat metabolic diseases and implicate STAT3 as a new target for the development of functional foods and drugs. PMID:24316209

  12. Novel high-throughput screening system for identifying STAT3-SH2 antagonists

    SciTech Connect

    Uehara, Yutaka; Mochizuki, Masato; Matsuno, Kenji; Haino, Takeharu; Asai, Akira

    2009-03-13

    Constitutive activation of the oncogenic transcription factor STAT3 frequently occurs in various human malignancies. STAT3 activation involves dimerization via intermolecular pTyr-SH2 interaction. Thus, antagonizing this interaction is a feasible approach to inhibit STAT3 activation for cancer therapy. In order to identify selective STAT3 inhibitors, we developed a biochemical HTS system based on AlphaScreen technology, which measures the abilities of test compounds to antagonize pTyr-SH2 interactions. We screened our chemical libraries using this system and identified 5,15-diphenylporphyrin (5,15-DPP) as a selective STAT3-SH2 antagonist. Selective inhibition of STAT3 nuclear translocation and DNA biding activity was observed in cells treated with 5,15-DPP. IL-6-dependent dimerization of STAT3, c-myc promoter binding and c-myc protein expression were all suppressed by 5,15-DPP, whereas no decrement in either expression or phosphorylation level of STAT3 was observed. Thus, the HTS assay system represented herein may be useful for identifying novel STAT3-SH2 antagonists.

  13. STAT3 paradoxically stimulates β-catenin expression but inhibits β-catenin function

    PubMed Central

    Ibrahem, Salih; Al-Ghamdi, Saleh; Baloch, Kanwal; Muhammad, Belal; Fadhil, Wakkas; Jackson, Darryl; Nateri, Abdolrahman S; Ilyas, Mohammad

    2014-01-01

    Wnt signalling and the signal transducer and activator of transcription 3 (STAT3) are oncogenic signalling pathways which are deregulated in colorectal cancer (CRC). Here we investigated the interaction of these two pathways. Firstly, we investigated biochemical interaction by inhibiting STAT3 and β-catenin (through gene knock-down and dominant-negative TCF4 expression) in nine CRC cell lines. β-catenin inhibition did not affect STAT3 levels, whereas STAT3 knock-down resulted in reduced β-catenin mRNA and protein levels. The reduction in β-catenin protein was not prevented by proteasome inhibition, and IL6-induced STAT3 activation resulted in increased β-catenin mRNA. This suggests that STAT3 positively regulates β-catenin (at a transcriptional level) and evaluation of 44 CRCs by immunostaining supported this by showing an association between nuclear STAT3 expression and nuclear β-catenin (P = 0.022). We tested the functional interaction between STAT3 and Wnt signalling by knocking down STAT3 and β-catenin individually and in combination. Knock-down of β-catenin and STAT3 individually inhibited cell proliferation (P < 0. 001 for each) through G1 arrest. However, simultaneous knock-down of STAT3 and β-catenin had a significantly weaker effect than knock-down of β-catenin alone (P < 0.01). Knock-down of STAT3 and β-catenin, individually and together, inhibited cell motility (P < 0.001) without evidence of interaction. We conclude that STAT3 regulates β-catenin but β-catenin does not regulate STAT3. The STAT3/β-catenin interaction is complex but may reduce the proliferative activity of β-catenin possibly by taking β-catenin protein beyond the optimal level. This may indicate biological differences in tumours where both STAT3 and β-catenin are activated compared to those where only one is activated. PMID:25348333

  14. Identification of STAT1 and STAT3 Specific Inhibitors Using Comparative Virtual Screening and Docking Validation

    PubMed Central

    Szelag, Malgorzata; Czerwoniec, Anna; Wesoly, Joanna; Bluyssen, Hans A. R.

    2015-01-01

    Signal transducers and activators of transcription (STATs) facilitate action of cytokines, growth factors and pathogens. STAT activation is mediated by a highly conserved SH2 domain, which interacts with phosphotyrosine motifs for specific STAT-receptor contacts and STAT dimerization. The active dimers induce gene transcription in the nucleus by binding to a specific DNA-response element in the promoter of target genes. Abnormal activation of STAT signaling pathways is implicated in many human diseases, like cancer, inflammation and auto-immunity. Searches for STAT-targeting compounds, exploring the phosphotyrosine (pTyr)-SH2 interaction site, yielded many small molecules for STAT3 but sparsely for other STATs. However, many of these inhibitors seem not STAT3-specific, thereby questioning the present modeling and selection strategies of SH2 domain-based STAT inhibitors. We generated new 3D structure models for all human (h)STATs and developed a comparative in silico docking strategy to obtain further insight into STAT-SH2 cross-binding specificity of a selection of previously identified STAT3 inhibitors. Indeed, by primarily targeting the highly conserved pTyr-SH2 binding pocket the majority of these compounds exhibited similar binding affinity and tendency scores for all STATs. By comparative screening of a natural product library we provided initial proof for the possibility to identify STAT1 as well as STAT3-specific inhibitors, introducing the ‘STAT-comparative binding affinity value’ and ‘ligand binding pose variation’ as selection criteria. In silico screening of a multi-million clean leads (CL) compound library for binding of all STATs, likewise identified potential specific inhibitors for STAT1 and STAT3 after docking validation. Based on comparative virtual screening and docking validation, we developed a novel STAT inhibitor screening tool that allows identification of specific STAT1 and STAT3 inhibitory compounds. This could increase our

  15. STAT5 Outcompetes STAT3 To Regulate the Expression of the Oncogenic Transcriptional Modulator BCL6

    PubMed Central

    Walker, Sarah R.; Nelson, Erik A.; Yeh, Jennifer E.; Pinello, Luca; Yuan, Guo-Cheng

    2013-01-01

    Inappropriate activation of the transcription factors STAT3 and STAT5 has been shown to drive cancer pathogenesis through dysregulation of genes involved in cell survival, growth, and differentiation. Although STAT3 and STAT5 are structurally related, they can have opposite effects on key genes, including BCL6. BCL6, a transcriptional repressor, has been shown to be oncogenic in diffuse large B cell lymphoma. BCL6 also plays an important role in breast cancer pathogenesis, a disease in which STAT3 and STAT5 can be activated individually or concomitantly. To determine the mechanism by which these oncogenic transcription factors regulate BCL6 transcription, we analyzed their effects at the levels of chromatin and gene expression. We found that STAT3 increases expression of BCL6 and enhances recruitment of RNA polymerase II phosphorylated at a site associated with transcriptional initiation. STAT5, in contrast, represses BCL6 expression below basal levels and decreases the association of RNA polymerase II at the gene. Furthermore, the repression mediated by STAT5 is dominant over STAT3-mediated induction. STAT5 exerts this effect by displacing STAT3 from one of the two regulatory regions to which it binds. These findings may underlie the divergent biology of breast cancers containing activated STAT3 alone or in conjunction with activated STAT5. PMID:23716595

  16. STAT3 Impairs STAT5 Activation in the Development of IL-9-Secreting T Cells.

    PubMed

    Olson, Matthew R; Verdan, Felipe Fortino; Hufford, Matthew M; Dent, Alexander L; Kaplan, Mark H

    2016-04-15

    Th cell subsets develop in response to multiple activating signals, including the cytokine environment. IL-9-secreting T cells develop in response to the combination of IL-4 and TGF-β, although they clearly require other cytokine signals, leading to the activation of transcription factors including STAT5. In Th17 cells, there is a molecular antagonism of STAT5 with STAT3 signaling, although whether this paradigm exists in other Th subsets is not clear. In this paper, we demonstrate that STAT3 attenuates the ability of STAT5 to promote the development of IL-9-secreting T cells. We demonstrate that production of IL-9 is increased in the absence of STAT3 and cytokines that result in a sustained activation of STAT3, including IL-6, have the greatest potency in repressing IL-9 production in a STAT3-dependent manner. Increased IL-9 production in the absence of STAT3 correlates with increased endogenous IL-2 production and STAT5 activation, and blocking IL-2 responses eliminates the difference in IL-9 production between wild-type and STAT3-deficient T cells. Moreover, transduction of developing Th9 cells with a constitutively active STAT5 eliminates the ability of IL-6 to reduce IL-9 production. Thus, STAT3 functions as a negative regulator of IL-9 production through attenuation of STAT5 activation and function. PMID:26976954

  17. Function of shrimp STAT during WSSV infection.

    PubMed

    Wen, Rong; Li, Fuhua; Li, Shihao; Xiang, Jianhai

    2014-06-01

    JAK/STAT signaling pathway plays key roles in the antiviral immunity of mammals, fish and insect. However, limited knowledge is known about the function of JAK/STAT signaling pathway in the antiviral immunity of shrimp although virus disease has caused severe mortality in shrimp aquaculture. In order to understand the function of JAK/STAT signaling pathway in the antiviral immunity of shrimp, dsRNA interfering technique was used to silence the expression of STAT gene in Litopenaeus vannamei, and the mortality of shrimp was detected after WSSV infection. Furthermore, the expressions of some potential target genes regulated by STAT or genes related to RNA interfering pathway were detected in STAT silenced shrimp during WSSV infection. The WSSV copy number in STAT silenced shrimp was 10(2)-10(3) copies/ng DNA which was much lower than that in the control. The mortality in STAT silenced shrimp caused by WSSV infection decreased very significantly compared to their controls. The function of STAT was verified in vitro cultured cells of hematopoietic tissue of crayfish Cherax quadricarinatus by adding specific inhibitor of STAT3(S3I-201), and the cultured cells treated with S3I-201 showed much less WSSV copy number than their controls, which further suggested that STAT might be helpful for the replication of WSSV. Expression analysis on the potential STAT target genes and genes in RNA interfering pathway provide important information for understanding the functional mechanism of STAT in antiviral immunity of shrimp. PMID:24727196

  18. Serotyping of Campylobacter jejuni by slide agglutination based on heat-labile antigenic factors.

    PubMed Central

    Lior, H; Woodward, D L; Edgar, J A; Laroche, L J; Gill, P

    1982-01-01

    A serotyping scheme for Campylobacter jejuni was developed based on slide agglutination of live bacteria with whole cell antisera absorbed with homologous heated and heterologous unheated cross-reactive antigens. Among 815 isolates from human and nonhuman sources, 21 serogroups were recognized. Of the 615 isolates from human cases of gastroenteritis, 529 (86%) were typable; 455 strains agglutinated in 20 single antisera, whereas 74 isolates agglutinated in various pairs of antisera, allowing subdivision of some main serogroups into subserogroups. Of the 200 isolates of C. jejuni from nonhuman sources (chicken, swine, etc.), 166 (83%) were typable, 145 cultures agglutinated in various single antisera, and 21 strains agglutinated with different pairs of antisera. Among isolates from all sources, 8 serogroups (1, 2, 4, 5, 7, 8, 9, and 11) were encountered most frequently. Serogroups 1, 2, 4, 5, 7, 9, and 11 were most common among human isolates; the majority of the chicken and all of the swine isolates belonged to the same serogroups identified from human cases. Very good serological correlation was obtained in 20 family outbreaks and 4 community outbreaks. PMID:7096555

  19. Epibenthic, agglutinating foraminiferans in the Santa Catalina Basin and their response to disturbance

    NASA Astrophysics Data System (ADS)

    Levin, Lisa A.; Childers, Susan E.; Smith, Craig R.

    1991-04-01

    There are five common species of large (0.5-6 cm long) epibenthic, agglutinating foraminiferans in the Santa Catalina Basin (1200-1350 m). This paper describes their basic ecology and response to mound disturbance. Combined, the five species attain mean densities of 200-300 individuals per m 2 and their protoplasm has an average biomass of 199.5 mg m -2. Individual species occur at densities ranging from 7 to 100 m -2, and each species has a different population size structure. Protoplasm comprises <2% of test volumes. Analysis of excess 234Th revealed no indication of particle sequestering within tests, and acridine orange direct counts of bacteria provided no evidence of microbial gardening or enhancement associated with tests. Twenty-five per cent of tests examined had metazoan associates; approximately half of these were polychaetes. Experiments were carried out to investigate the response of the epibenthic foraminiferal assemblage to disturbance from large, biogenic mounds, a common feature on the Santa Catalina Basin floor. Three branched forms, Pelosina cf. arborescens, P. cf. cylindrica and a mud-walled astrorhizinid, were most abundant on background sediments, less common on natural mounds and absent from artificially-created mounds exposed for 10.5 months. Two spherical species, Oryctoderma sp. and a different mud-walled astrorhizinid, were present at similar densities on artificial mounds (9.5-10.5 months old), natural mounds and undisturbed sediments, but Oryctoderma sp. attained largest sizes on mounds. These two species appear to be opportunistic taxa that can colonize and grow rapidly on mound sediments. This study suggests that disturbance, in this case that by sediment mound builders, is an important source of spatial heterogeneity in deep-water foraminiferal communities. Where sediment mounds occur, foraminiferal assemblages will experience disequilibrium dynamics.

  20. NAB2-STAT6 fusion types account for clinicopathological variations in solitary fibrous tumors.

    PubMed

    Tai, Hui-Chun; Chuang, I-Chieh; Chen, Tse-Ching; Li, Chien-Feng; Huang, Shih-Chiang; Kao, Yu-Chien; Lin, Po-Chun; Tsai, Jen-Wei; Lan, Jui; Yu, Shih-Chen; Yen, Shao-Lun; Jung, Shih-Ming; Liao, Kuan-Cho; Fang, Fu-Min; Huang, Hsuan-Ying

    2015-10-01

    Solitary fibrous tumor (SFT) is characterized by the inv12(q13q13)-derived NAB2-STAT6 fusion, which exhibits variable breakpoints and drives STAT6 nuclear expression. The implications of NAB2-STAT6 fusion variants in pathological features and clinical behavior remain to be characterized in a large cohort of SFTs. We investigated the clinicopathological correlates of this genetic hallmark and analyzed STAT6 immunoexpression in 28 intrathoracic, 37 extrathoracic, and 23 meningeal SFTs. These 88 tumors were designated as histologically nonmalignant in 75 cases and malignant in 13, including 1 dedifferentiated SFT. Eighty cases had formalin-fixed and/or fresh samples to extract assessable RNAs for RT-PCR assay, which revealed NAB2-STAT6 fusion variants comprising 12 types of junction breakpoints in 73 fusion-positive cases, with 65 (89%) falling into 3 major types. The predominant NAB2ex4-STAT6ex2 (n=33) showed constant breakpoints at the ends of involved exons, whereas the NAB2ex6-STAT6ex16 (n=16) and NAB2ex6-STAT6ex17 (n=16) might exhibit variable breakpoints and incorporate NAB2 or STAT6 intronic sequence. Including 73 fusion-positive and 7 CD34-negative SFTs, STAT6 distinctively labeled 87 (99%) SFTs in nuclei, exhibited diffuse reactivity in 73, but did not decorate 98 mimics tested. In seven fusion-negative cases, 6 were STAT6-positive, suggesting rare fusion variants not covered by RT-PCR assay. Regardless of histological subtypes, intrathoracic SFTs affected older patients (P=0.035) and tended to be larger in size (P=0.073). Compared with other variants, NAB2ex4-STAT6ex2/4 fusions were significantly predominant in the SFTs characterised by intrathoracic location (P<0.001), older age (P=0.005), decreased mitoses (P=0.0028), and multifocal or diffuse STAT6 staining (P=0.013), but not found to correlate with disease-free survival. Conclusively, STAT6 nuclear expression was distinctive in the vast majority of SFTs, including all fusion-positive tumors, and

  1. Role of STAT3 in lung cancer

    PubMed Central

    Dutta, Pranabananda; Sabri, Nafiseh; Li, Jinghong; Li, Willis X

    2014-01-01

    Lung cancer remains a challenging disease. It is responsible for the high cancer mortality rates in the US and worldwide. Elucidation of the molecular mechanisms operative in lung cancer is an important first step in developing effective therapies. Accumulating evidence over the last 2 decades suggests a critical role for Signal Transducer and Activator of Transcription 3 (STAT3) as a point of convergence for various signaling pathways that are dysregulated in the disease. In this review, we discuss possible molecular mechanisms involving STAT3 in lung tumorigenesis based on recent literature. We consider possible roles of STAT3 in cancer cell proliferation and survival, in the tumor immune environment, and in epigenetic regulation and interaction of STAT3 with other transcription factors. We also discuss the potential role of STAT3 in tumor suppression, which complicates strategies of targeting STAT3 in cancer therapy. PMID:26413424

  2. STAT3 Signaling in Polycystic Kidney Disease

    PubMed Central

    Weimbs, Thomas; Talbot, Jeffrey J.

    2015-01-01

    Mutations in the gene coding for the integral membrane protein polycystin-1 (PC1) are the cause of most cases of autosomal-dominant polycystic kidney disease (ADPKD), a very common disease that leads to kidney failure and currently lacks approved treatment. Recent work has revealed that PC1 can regulate the transcription factor STAT3, and that STAT3 is aberrantly activated in the kidneys of ADPKD patients and PKD mouse models. Recent approaches to directly inhibit STAT3 in PKD mouse models have been promising. Numerous signaling pathways are known to activate STAT3 and many have long been implicated in the pathogenesis of PKD - such as EGF/EGFR, HGF/c-Met, Src. However, a role of STAT3 in the pathogenesis of PKD had never been considered until now. Here, we review the current findings that suggest that STAT3 is a promising target for the treatment of PKD. PMID:26523147

  3. Serological grouping of meningococci and encapsulated Haemophilus influenzae strains by latex agglutination.

    PubMed Central

    Leinonen, M; Sivonen, A

    1979-01-01

    The latex agglutination method, utilizing antibody-coated latex particles, was adapted for serogrouping of Neisseria meningitidis and serotyping of encapsulated Haemophilus influenzae strains from agar plates. It was found to give more clear-cut results than conventional slide agglutination. A 100% agreement with the antiserum agar method was found for all strains isolated from blood or cerebrospinal fluid. Many meningococcal strains from nasopharyngeal carriers are autoagglutinable, but some of these gave a positive reaction with the group B latex reagent, although they were negative by the antiserum agar method. The latex agglutination method has several advantages over others: the lack of autoagglutination, easy performance, easy interpretation, and very low consumption of antisera. PMID:118981

  4. Insertional Mutagenesis Identifies a STAT3/Arid1b/β-catenin Pathway Driving Neurofibroma Initiation.

    PubMed

    Wu, Jianqiang; Keng, Vincent W; Patmore, Deanna M; Kendall, Jed J; Patel, Ami V; Jousma, Edwin; Jessen, Walter J; Choi, Kwangmin; Tschida, Barbara R; Silverstein, Kevin A T; Fan, Danhua; Schwartz, Eric B; Fuchs, James R; Zou, Yuanshu; Kim, Mi-Ok; Dombi, Eva; Levy, David E; Huang, Gang; Cancelas, Jose A; Stemmer-Rachamimov, Anat O; Spinner, Robert J; Largaespada, David A; Ratner, Nancy

    2016-03-01

    To identify genes and signaling pathways that initiate Neurofibromatosis type 1 (NF1) neurofibromas, we used unbiased insertional mutagenesis screening, mouse models, and molecular analyses. We mapped an Nf1-Stat3-Arid1b/β-catenin pathway that becomes active in the context of Nf1 loss. Genetic deletion of Stat3 in Schwann cell progenitors (SCPs) and Schwann cells (SCs) prevents neurofibroma formation, decreasing SCP self-renewal and β-catenin activity. β-catenin expression rescues effects of Stat3 loss in SCPs. Importantly, P-STAT3 and β-catenin expression correlate in human neurofibromas. Mechanistically, P-Stat3 represses Gsk3β and the SWI/SNF gene Arid1b to increase β-catenin. Knockdown of Arid1b or Gsk3β in Stat3(fl/fl);Nf1(fl/fl);DhhCre SCPs rescues neurofibroma formation after in vivo transplantation. Stat3 represses Arid1b through histone modification in a Brg1-dependent manner, indicating that epigenetic modification plays a role in early tumorigenesis. Our data map a neural tumorigenesis pathway and support testing JAK/STAT and Wnt/β-catenin pathway inhibitors in neurofibroma therapeutic trials. PMID:26904939

  5. The relationship of the lunar regolith less than 10 micrometer fraction and agglutinates. I - A model for agglutinate formation and some indirect supportive evidence

    NASA Technical Reports Server (NTRS)

    Papike, J. J.; Simon, S. B.; White, C.; Laul, J. C.

    1982-01-01

    The first part of a study of the 'less than 10 micrometer' soil fraction and agglutinates is concerned with the chemical systematics of the considered fraction of lunar soils, taking into account a model for agglutinate formation based on the fusion of the finest fraction (FFF). Attention is given to some evidence which supports the FFF model. The evidence is based on some indirect approaches to an estimation of the composition of the fused soil component. It is found that the 'less than 10 micrometer' soil fraction from all Apollo sites except Apollo 16 (which can be explained) is more feldspathic and enriched in incompatible elements (e.g., K and Th) than the bulk soil. It is concluded that these systematics result from simple comminution in which feldspar breaks down to finer sizes than pyroxene and olivine and the fine-grained incompatible-element-enriched mesostasis concentrates in the 'less than 10 micrometer' soil fraction.

  6. Screening approaches to generating STAT inhibitors

    PubMed Central

    Walker, Sarah R.; Frank, David A.

    2012-01-01

    STAT transcription factors are regulators of critical cellular processes such as proliferation, survival, and self-renewal. While the activity of these proteins is tightly regulated under physiological conditions, they can become constitutively activated in a broad range of human cancers. This inappropriate STAT activation leads to enhanced transcription of genes that can directly lead to the malignant phenotype. Since STATs are largely dispensable for normal cell function, this has raised the possibility that STATs might be key targets for cancer therapy. Although a number of structure-based strategies have been used to develop STAT inhibitors, an alternate approach is to use cell-based assays that make use of the transcriptional function of STATs. Employing these systems, one can screen large chemical libraries to identify compounds that specifically block the function of a given STAT. This approach can lead to the identification of compounds that inhibit STATs by a variety of mechanisms, and can suggest novel targets for therapy. This type of functional screening strategy has already identified a drug that potently inhibits STAT3, and which is now being evaluated in a clinical trial for patients with chronic lymphocytic leukemia. PMID:24058786

  7. Agglutinates as recorders of fossil soil compositions. [of Apollo 17 lunar probes

    NASA Technical Reports Server (NTRS)

    Taylor, G. J.; Wentworth, S.; Warner, R. D.; Keil, K.

    1978-01-01

    The composition of agglutinates in polished sections of the Apollo 17 drill core was studied in an attempt to deduce the nature of the Taurus-Littrow valley regolith prior to the formation of the Camelot and Central Cluster craters. The agglutinate compositions in the soils differed from the host soil compositions except for samples from the North Massif. Local materials from the valley floor and the massifs appear to form the pre-Central Cluster regolith. It is also shown that chemical mixing models for bulk soil compositions can be misleading unless the petrologic characteristics of each soil are taken into account.

  8. Impact of the N-Terminal Domain of STAT3 in STAT3-Dependent Transcriptional Activity.

    PubMed

    Hu, Tiancen; Yeh, Jennifer E; Pinello, Luca; Jacob, Jaison; Chakravarthy, Srinivas; Yuan, Guo-Cheng; Chopra, Rajiv; Frank, David A

    2015-10-01

    The transcription factor STAT3 is constitutively active in many cancers, where it mediates important biological effects, including cell proliferation, differentiation, survival, and angiogenesis. The N-terminal domain (NTD) of STAT3 performs multiple functions, such as cooperative DNA binding, nuclear translocation, and protein-protein interactions. However, it is unclear which subsets of STAT3 target genes depend on the NTD for transcriptional regulation. To identify such genes, we compared gene expression in STAT3-null mouse embryonic fibroblasts (MEFs) stably expressing wild-type STAT3 or STAT3 from which NTD was deleted. NTD deletion reduced the cytokine-induced expression of specific STAT3 target genes by decreasing STAT3 binding to their regulatory regions. To better understand the potential mechanisms of this effect, we determined the crystal structure of the STAT3 NTD and identified a dimer interface responsible for cooperative DNA binding in vitro. We also observed an Ni(2+)-mediated oligomer with an as yet unknown biological function. Mutations on both dimer and Ni(2+)-mediated interfaces affected the cytokine induction of STAT3 target genes. These studies shed light on the role of the NTD in transcriptional regulation by STAT3 and provide a structural template with which to design STAT3 NTD inhibitors with potential therapeutic value. PMID:26169829

  9. Outbreak of Uncommon O4 Non-Agglutinating Salmonella Typhimurium Linked to Minced Pork, Saxony-Anhalt, Germany, January to April 2013

    PubMed Central

    Helmeke, Carina; Kohlstock, Claudia; Prager, Rita; Tietze, Erhard; Rabsch, Wolfgang; Karagiannis, Ioannis; Werber, Dirk; Frank, Christina; Fruth, Angelika

    2015-01-01

    Introduction In January 2013, the National Reference Centre for Salmonella (NRC) detected a salmonellosis cluster in Saxony-Anhalt, Germany, caused by uncommon O4 non-agglutinating, monophasic Salmonella (S.) Typhimurium DT193. Circulating predominant monophasic S. Typhimurium DT193 clones typically display resistance phenotype ASSuT. We investigated common exposures to control the outbreak, and conducted microbiological investigations to assess the strains’ phenotype. Methods We conducted a case-control study defining cases as persons living or working in Saxony-Anhalt diagnosed with the O4 non-agglutinating strain between January and March 2013. We selected two controls contemporarily reported with norovirus infection, frequency-matched on residence and age group, per case. We interviewed regarding food consumption, especially pork and its place of purchase. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI) using logistic regression. The NRC investigated human and food isolates by PCR, SDS-PAGE, MLST, PFGE, MLVA and susceptibility testing. Results Altogether, 68 O4 non-agglutinating human isolates were confirmed between January and April 2013. Of those, 61 were assigned to the outbreak (median age 57 years, 44% female); 83% cases ≥ 60 years were hospitalized. Eating raw minced pork from butcheries within 3 days was associated with disease (31 cases, 28 controls; OR adjusted for sex: 3.6; 95% CI: 1.0-13). Phage type DT193 and MLST ST34 were assigned, and isolates’ lipopolysaccharide (LPS) matched control strains. Isolates linked to Saxony-Anhalt exhibited PFGE type 5. ASSuT- and ACSSuT phenotype proportions were 34 and 39% respectively; 54% were resistant to chloramphenicol. Three pork isolates matched the outbreak strain. Discussion Raw minced pork was the most likely infection vehicle in this first reported outbreak caused by O4 non-agglutinating, mostly chloramphenicol-resistant S. Typhimurium DT193. High hospitalization proportions

  10. Opposing roles of STAT1 and STAT3 in IL-21 function in CD4+ T cells.

    PubMed

    Wan, Chi-Keung; Andraski, Allison B; Spolski, Rosanne; Li, Peng; Kazemian, Majid; Oh, Jangsuk; Samsel, Leigh; Swanson, Phillip A; McGavern, Dorian B; Sampaio, Elizabeth P; Freeman, Alexandra F; Milner, Joshua D; Holland, Steven M; Leonard, Warren J

    2015-07-28

    IL-21 is a type I cytokine essential for immune cell differentiation and function. Although IL-21 can activate several STAT family transcription factors, previous studies focused mainly on the role of STAT3 in IL-21 signaling. Here, we investigated the role of STAT1 and show that STAT1 and STAT3 have at least partially opposing roles in IL-21 signaling in CD4(+) T cells. IL-21 induced STAT1 phosphorylation, and this was augmented in Stat3-deficient CD4(+) T cells. RNA-Seq analysis of CD4(+) T cells from Stat1- and Stat3-deficient mice revealed that both STAT1 and STAT3 are critical for IL-21-mediated gene regulation. Expression of some genes, including Tbx21 and Ifng, was differentially regulated by STAT1 and STAT3. Moreover, opposing actions of STAT1 and STAT3 on IFN-γ expression in CD4(+) T cells were demonstrated in vivo during chronic lymphocytic choriomeningitis infection. Finally, IL-21-mediated induction of STAT1 phosphorylation, as well as IFNG and TBX21 expression, were higher in CD4(+) T cells from patients with autosomal dominant hyper-IgE syndrome, which is caused by STAT3 deficiency, as well as in cells from STAT1 gain-of-function patients. These data indicate an interplay between STAT1 and STAT3 in fine-tuning IL-21 actions. PMID:26170288

  11. Single agglutinates: A comparative study of compositions of agglutinitic glass, whole-grain, bulk soil, and FMR

    NASA Technical Reports Server (NTRS)

    Basu, A.; Robinson, R.; Mckay, D. S.; Blanchard, D. P.; Morris, R. V.; Wentworth, Susan J.

    1994-01-01

    Previous workers on single agglutinates have variously interpreted the composition of agglutinitic glass to represent impact melts of (1) bulk soil, (2) mixed components in finer sizes, and (3) microtargets. Separately, Papike has argued in favor of fusion of the finest fraction of bulk soils. Thirty-four single agglutinates were hand-picked from the mature Apollo 16 soil 61181 (I(sub s)/FeO = 82) and the FMR and chemical composition (INAA for Fe, Sc, Sm, Co, Ni, and Cr) of each agglutinate particle were measured. Thirteen of these single agglutinates were selected for electron beam microanalysis and imaging. Less than 1 micron spots were analyzed (for Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Mn, Fe, Ni, and Ba) on pure glassy areas (approximately ten in each particle) selected on the basis of optical and BSE images (avoiding all clasts and inclusions) with an electron microprobe to obtain average glass compositions of each single agglutinate.

  12. Agglutinating monoclonal antibodies that specifically recognize lipooligosaccharide A of Bordetella pertussis.

    PubMed Central

    Li, Z M; Cowell, J L; Brennan, M J; Burns, D L; Manclark, C R

    1988-01-01

    Monoclonal antibodies that specifically agglutinate strains of Bordetella pertussis having serotype 1 agglutinogen were uniquely reactive with the electrophoretically slow-migrating A form of lipooligosaccharide. These monoclonal antibodies should be useful for the structural analysis of B. pertussis lipooligosaccharide and for the establishment of a better-defined serogroup for Bordetella species. Images PMID:2893776

  13. Agglutinating monoclonal antibodies that specifically recognize lipooligosaccharide A of Bordetella pertussis.

    PubMed

    Li, Z M; Cowell, J L; Brennan, M J; Burns, D L; Manclark, C R

    1988-03-01

    Monoclonal antibodies that specifically agglutinate strains of Bordetella pertussis having serotype 1 agglutinogen were uniquely reactive with the electrophoretically slow-migrating A form of lipooligosaccharide. These monoclonal antibodies should be useful for the structural analysis of B. pertussis lipooligosaccharide and for the establishment of a better-defined serogroup for Bordetella species. PMID:2893776

  14. An integrated fiberoptic-microfluidic device for agglutination detection and blood typing.

    PubMed

    Ramasubramanian, Melur K; Alexander, Stewart P

    2009-02-01

    In this paper, an integrated fiberoptic-microfluidic device for the detection of agglutination for blood type cross-matching has been described. The device consists of a straight microfluidic channel through with a reacted RBC suspension is pumped with the help of a syringe pump. The flow intersects an optical path created by an emitter-received fiber optic pair integrated into the microfluidic device. A 650 nm laser diode is used as the light source and a silicon photodiode is used to detect the light intensity. The spacing between the tips of the two optic fibers can be adjusted. When fiber spacing is large and the concentration of the suspension is high, scattering phenomenon becomes the dominant mechanism for agglutination detection while at low concentrations and small spacing, optointerruption becomes the dominant mechanism. An agglutination strength factor (ASF) is calculated from the data. Studies with a variety of blood types indicate that the sensing method correctly identifies the agglutination reaction in all cases. A disposable integrated device can be designed for future implementation of the method for near-bedside pre-transfusion check. PMID:18815884

  15. Avian P1 antigens inhibit agglutination mediated by P fimbriae of uropathogenic Escherichia coli.

    PubMed Central

    Johnson, J R; Swanson, J L; Neill, M A

    1992-01-01

    Whole egg white from pigeon, dove, and cockatiel eggs, as well as the ovomucoid fraction of pigeon egg white, exhibited strong P1 antigenic activities and inhibited agglutination of human P1 erythrocytes and of digalactoside-coated latex beads by P-fimbriated Escherichia coli strains. In contrast, chicken egg white exhibited only weak P1 antigenic activity and had little impact on P-fimbrial agglutination. These preparations did not affect hemagglutination by E. coli strains expressing mannose-resistant adhesins other than P fimbriae, i.e., Dr, F1845, and S adhesins. Human anti-P1 serum diminished the P-fimbrial inhibitory activities of pigeon egg white and pigeon ovomucoid. Pigeon ovomucoid was equipotent on a molar basis with globoside, and the pigeon, dove, and cockatiel egg white preparations were equipotent with each other in P-fimbrial inhibition. Incubation of p erythrocytes in whole egg whites or in pigeon ovomucoid did not render them agglutinable by P-fimbriated bacteria, whereas incubation in globoside did. These data demonstrate that whole egg whites (and their ovomucoid fraction) from members of the families Columbidae (pigeons and doves) and Psittacidae (parrots) specifically and potently inhibit P-fimbrial agglutination, probably by providing P1 antigen as a receptor for the P-fimbrial adhesin. Avian egg white preparations may facilitate adhesin characterization of wild-type uropathogenic strains and may useful in preventing upper urinary tract infections due to P-fimbriated E. coli. PMID:1346125

  16. Antibody-mediated red blood cell agglutination resulting in spontaneous echocardiographic contrast.

    PubMed

    Miller, M R; Thompson, W R; Casella, J F; Spevak, P J

    1999-01-01

    Spontaneous echocardiographic contrast is well reported in states of low flow and low shear stress, and the primary blood component involved has been reported as red blood cells via rouleaux formation. This report describes the occurrence of spontaneous echocardiographic contrast from a unique mechanism of IgM-mediated red blood cell agglutination and describes the clinical sequelae. PMID:10368455

  17. Capsular gene typing of Streptococcus agalactiae compared to serotyping by latex agglutination.

    PubMed

    Yao, Kaihu; Poulsen, Knud; Maione, Domenico; Rinaudo, C Daniela; Baldassarri, Lucilla; Telford, John L; Sørensen, Uffe B Skov; Kilian, Mogens

    2013-02-01

    We evaluated three different PCR-based capsular gene typing methods applied to 312 human and bovine Streptococcus agalactiae (group B Streptococcus [GBS]) isolates and compared the results to serotyping results obtained by latex agglutination. Among 281 human isolates 27% could not be typed by latex agglutination. All 312 isolates except 5 could be typed by the three PCR methods combined. Two of these methods were multiplex assays. Among the isolates that were typeable by both latex agglutination and capsular gene typing, 94% showed agreement between the two methods. However, each of the PCR methods showed limitations. One of the methods did not include all 10 recognized serotypes, one misidentified eight isolates of serotypes Ib and IV as serotype Ia, and one did not distinguish between serotypes VII and IX. For five isolates that showed aberrant patterns in the capsular gene typing, long-range PCR targeting the cps operon disclosed large insertions or deletions affecting the cps gene cluster. A sensitive flow cytometric assay based on serotype-specific antibodies applied to 76 selected isolates that were nontypeable by latex agglutination revealed that approximately one-half of these did express capsular polysaccharide. A procedure for convenient and reliable capsular gene typing to be included in epidemiological and surveillance studies of S. agalactiae is proposed. PMID:23196363

  18. STATs in cancer inflammation and immunity: a leading role for STAT3

    PubMed Central

    Yu, Hua; Pardoll, Drew; Jove, Richard

    2016-01-01

    Commensurate with their roles in regulating cytokine-dependent inflammation and immunity, signal transducer and activator of transcription (STAT) proteins are central in determining whether immune responses in the tumour microenvironment promote or inhibit cancer. Persistently activated STAT3 and, to some extent, STAT5 increase tumour cell proliferation, survival and invasion while suppressing anti-tumour immunity. The persistent activation of STAT3 also mediates tumour-promoting inflammation. STAT3 has this dual role in tumour inflammation and immunity by promoting pro-oncogenic inflammatory pathways, including nuclear factor-κB (NF-κB) and interleukin-6 (IL-6)–GP130–Janus kinase (JAK) pathways, and by opposing STAT1- and NF-κB-mediated T helper 1 anti-tumour immune responses. Consequently, STAT3 is a promising target to redirect inflammation for cancer therapy. PMID:19851315

  19. Persistent GP130/STAT3 Signaling Contributes to the Resistance of Doxorubicin, Cisplatin, and MEK Inhibitor in Human Rhabdomyosarcoma Cells

    PubMed Central

    Wu, Xiaojuan; Xiao, Hui; Wang, Ruoning; Liu, Lingling; Li, Chenglong; Lin, Jiayuh

    2016-01-01

    To test the role of STAT3 in human rhabdomyosarcoma cells, genetic approaches were used to either knockdown the expression of STAT3 and GP130, an upstream activator of STAT3 using short hairpin RNA (shRNA) or express persistently active STAT3 protein. Knockdown expression of GP130 or STAT3 sensitized cells to anti-cancer drugs doxorubicin, cisplatin, and MEK inhibitor AZD6244. On the other hand, expression of the constitutively active STAT3 protein reduced the sensitivity of rhabdomyosarcoma cells to those drugs. In addition, we tested a small molecule STAT3 inhibitor LY5 and a GP130 inhibitor bazedoxifene in rhabdomyosarcoma cells. Our data demonstrated that the combination of LY5 or bazedoxifene with doxorubicin, cisplatin, and AZD6244 showed stronger inhibitory effects than single agent alone. In summary, our results demonstrated that GP130/STAT3 signaling contributes to the resistance of these drugs in rhabdomyosarcoma cells. They also suggested a potentially novel cancer therapeutic strategy using the combination of inhibitors of GP130/STAT3 signaling with doxorubicin, cisplatin, or AZD6244 for rhabdomyosarcoma treatments. PMID:26373715

  20. The Production of Nominal and Verbal Inflection in an Agglutinative Language: Evidence from Hungarian

    PubMed Central

    Peckham, Don; Szanka, Szilvia; Gazso, Dorottya; Lovassy, Noemi; Ullman, Michael T.

    2015-01-01

    The contrast between regular and irregular inflectional morphology has been useful in investigating the functional and neural architecture of language. However, most studies have examined the regular/irregular distinction in non-agglutinative Indo-European languages (primarily English) with relatively simple morphology. Additionally, the majority of research has focused on verbal rather than nominal inflectional morphology. The present study attempts to address these gaps by introducing both plural and past tense production tasks in Hungarian, an agglutinative non-Indo-European language with complex morphology. Here we report results on these tasks from healthy Hungarian native-speaking adults, in whom we examine regular and irregular nominal and verbal inflection in a within-subjects design. Regular and irregular nouns and verbs were stem on frequency, word length, and phonological structure, and both accuracy and response times were acquired. The results revealed that the regular/irregular contrast yields similar patterns in Hungarian, for both nominal and verbal inflection, as in previous studies of non-agglutinative Indo-European languages: the production of irregular inflected forms was both less accurate and slower than of regular forms, both for plural and past-tense inflection. The results replicate and extend previous findings to an agglutinative language with complex morphology. Together with previous studies, the evidence suggests that the regular/irregular distinction yields a basic behavioral pattern that holds across language families and linguistic typologies. Finally, the study sets the stage for further research examining the neurocognitive substrates of regular and irregular morphology in an agglutinative non-Indo-European language. PMID:25769039

  1. The production of nominal and verbal inflection in an agglutinative language: evidence from Hungarian.

    PubMed

    Nemeth, Dezso; Janacsek, Karolina; Turi, Zsolt; Lukacs, Agnes; Peckham, Don; Szanka, Szilvia; Gazso, Dorottya; Lovassy, Noemi; Ullman, Michael T

    2015-01-01

    The contrast between regular and irregular inflectional morphology has been useful in investigating the functional and neural architecture of language. However, most studies have examined the regular/irregular distinction in non-agglutinative Indo-European languages (primarily English) with relatively simple morphology. Additionally, the majority of research has focused on verbal rather than nominal inflectional morphology. The present study attempts to address these gaps by introducing both plural and past tense production tasks in Hungarian, an agglutinative non-Indo-European language with complex morphology. Here we report results on these tasks from healthy Hungarian native-speaking adults, in whom we examine regular and irregular nominal and verbal inflection in a within-subjects design. Regular and irregular nouns and verbs were stem on frequency, word length, and phonological structure, and both accuracy and response times were acquired. The results revealed that the regular/irregular contrast yields similar patterns in Hungarian, for both nominal and verbal inflection, as in previous studies of non-agglutinative Indo-European languages: the production of irregular inflected forms was both less accurate and slower than of regular forms, both for plural and past-tense inflection. The results replicate and extend previous findings to an agglutinative language with complex morphology. Together with previous studies, the evidence suggests that the regular/irregular distinction yields a basic behavioral pattern that holds across language families and linguistic typologies. Finally, the study sets the stage for further research examining the neurocognitive substrates of regular and irregular morphology in an agglutinative non-Indo-European language. PMID:25769039

  2. Interactions with lectins and agglutination profiles of clinical, food, and environmental isolates of Listeria.

    PubMed Central

    Facinelli, B; Giovanetti, E; Casolari, C; Varaldo, P E

    1994-01-01

    On the basis of preliminary trials with 14 collection strains of Listeria, five lectins (Canavalia ensiformis, concanavalin A; Griffonia simplicifolia lectin I; Helix pomatia agglutinin; Ricinus communis agglutinin; and Triticum vulgaris wheat germ agglutinin) were selected to set up a microtiter agglutination assay. The lectin agglutination profiles of 174 clinical, food, and environmental strains of Listeria monocytogenes, Listeria innocua, and Listeria seeligeri were investigated. Data on the standard determination of the antigenic structure were available for clinical strains; nonclinical isolates were assigned to serogroup 1 or 4 with commercial antisera. The listeria-lectin interaction was related to serological type rather than species; in particular, the strains assigned to serogroup 1 or belonging to serovars 1/2a, 1/2b, 1/2c, 3a, 3b, and 7 were never agglutinated by G. simplicifolia lectin I. The five-lectin set proved to be capable of detecting differences between serologically identical isolates of L. monocytogenes. Of the 150 isolates of this species, 144 were distributed over 15 different lectin agglutination profiles and 6 autoagglutinated, the overall typeability being 96%. However, the profiles encountered among L. monocytogenes isolates were not randomly distributed. With strains assigned to serogroup 1 or belonging to serovars 1/2a, 1/2b, 1/2c, and 3b, the clinical isolates fell into only two of the eight patterns recorded overall; with strains of serogroup 4 and serovar 4b, food and environmental isolates were distributed over eight of the nine patterns found in total, while clinical isolates were distributed over five patterns. In a comparative study of 15 epidemiologically relevant isolates of L. monocytogenes from five distinct outbreaks, strains with identical phage types and/or DNA fingerprints displayed identical lectin profiles. The heterogeneity of agglutination profiles may form the basis of a new approach to L. monocytogenes typing

  3. STAT signaling in the pathogenesis and treatment of myeloid malignancies

    PubMed Central

    Bar-Natan, Michal; Nelson, Erik A.; Xiang, Michael; Frank, David A.

    2012-01-01

    STAT transcription factors play a critical role in mediating the effects of cytokines on myeloid cells. As STAT target genes control key processes such as survival, proliferation and self-renewal, it is not surprising that constitutive activation of STATs, particularly STAT3 and STAT5, are common events in many myeloid tumors. STATs are activated both by mutant tyrosine kinases as well as other pathogenic events, and continued activation of STATs is common in the setting of resistance to kinase inhibitors. Thus, the targeting of STATs, alone or in combination with other drugs, will likely have increasing importance for cancer therapy. PMID:24058751

  4. Histone deacetylase inhibitors block IFNγ-induced STAT1 phosphorylation.

    PubMed

    Ginter, Torsten; Bier, Carolin; Knauer, Shirley K; Sughra, Kalsoom; Hildebrand, Dagmar; Münz, Tobias; Liebe, Theresa; Heller, Regine; Henke, Andreas; Stauber, Roland H; Reichardt, Werner; Schmid, Johannes A; Kubatzky, Katharina F; Heinzel, Thorsten; Krämer, Oliver H

    2012-07-01

    Signal transducer and activator of transcription 1 (STAT1) is important for innate and adaptive immunity. Histone deacetylase inhibitors (HDACi) antagonize unbalanced immune functions causing chronic inflammation and cancer. Phosphorylation and acetylation regulate STAT1 and different IFNs induce phosphorylated STAT1 homo-/heterodimers, e.g. IFNα activates several STATs whereas IFNγ only induces phosphorylated STAT1 homodimers. In transformed cells HDACi trigger STAT1 acetylation linked to dephosphorylation by the phosphatase TCP45. It is unclear whether acetylation differentially affects STAT1 activated by IFNα or IFNγ, and if cellular responses to both cytokines depend on a phosphatase-dependent inactivation of acetylated STAT1. Here, we report that HDACi counteract IFN-induced phosphorylation of a critical tyrosine residue in the STAT1 C-terminus in primary cells and hematopoietic cells. STAT1 mutants mimicking a functionally inactive DNA binding domain (DBD) reveal that the number of acetylation-mimicking sites in STAT1 determines whether STAT1 is recruited to response elements after stimulation with IFNγ. Furthermore, we show that IFNα-induced STAT1 heterodimers carrying STAT1 molecules mimicking acetylation bind cognate DNA and provide innate anti-viral immunity. IFNγ-induced acetylated STAT1 homodimers are though inactive, suggesting that heterodimerization and complex formation can rescue STAT1 lacking a functional DBD. Apparently, the type of cytokine determines how acetylation affects the nuclear entry and DNA binding of STAT1. Our data contribute to a better understanding of STAT1 regulation by acetylation. PMID:22425562

  5. Disruption of STAT5b-Regulated Sexual Dimorphism of the Liver Transcriptome by Diverse Factors Is a Common Event

    PubMed Central

    Oshida, Keiyu; Vasani, Naresh; Waxman, David J.; Corton, J. Christopher

    2016-01-01

    Signal transducer and activator of transcription 5b (STAT5b) is a growth hormone (GH)-activated transcription factor and a master regulator of sexually dimorphic gene expression in the liver. Disruption of the GH hypothalamo-pituitary-liver axis controlling STAT5b activation can lead to metabolic dysregulation, steatosis, and liver cancer. Computational approaches were developed to identify factors that disrupt STAT5b function in a mouse liver gene expression compendium. A biomarker comprised of 144 STAT5b-dependent genes was derived using comparisons between wild-type male and wild-type female mice and between STAT5b-null and wild-type mice. Correlations between the STAT5b biomarker gene set and a test set comprised of expression datasets (biosets) with known effects on STAT5b function were evaluated using a rank-based test (the Running Fisher algorithm). Using a similarity p-value ≤ 10−4, the test achieved a balanced accuracy of 99% and 97% for detection of STAT5b activation or STAT5b suppression, respectively. The STAT5b biomarker gene set was then used to identify factors that activate (masculinize) or suppress (feminize) STAT5b function in an annotated mouse liver and primary hepatocyte gene expression compendium of ~1,850 datasets. Disruption of GH-regulated STAT5b is a common phenomenon in liver in vivo, with 5% and 29% of the male datasets, and 11% and 13% of the female datasets, associated with masculinization or feminization, respectively. As expected, liver STAT5b activation/masculinization occurred at puberty and suppression/feminization occurred during aging and in mutant mice with defects in GH signaling. A total of 70 genes were identified that have effects on STAT5b activation in genetic models in which the gene was inactivated or overexpressed. Other factors that affected liver STAT5b function were shown to include fasting, caloric restriction and infections. Together, these findings identify diverse factors that perturb the hypothalamo

  6. Disruption of STAT5b-Regulated Sexual Dimorphism of the Liver Transcriptome by Diverse Factors Is a Common Event.

    PubMed

    Oshida, Keiyu; Vasani, Naresh; Waxman, David J; Corton, J Christopher

    2016-01-01

    Signal transducer and activator of transcription 5b (STAT5b) is a growth hormone (GH)-activated transcription factor and a master regulator of sexually dimorphic gene expression in the liver. Disruption of the GH hypothalamo-pituitary-liver axis controlling STAT5b activation can lead to metabolic dysregulation, steatosis, and liver cancer. Computational approaches were developed to identify factors that disrupt STAT5b function in a mouse liver gene expression compendium. A biomarker comprised of 144 STAT5b-dependent genes was derived using comparisons between wild-type male and wild-type female mice and between STAT5b-null and wild-type mice. Correlations between the STAT5b biomarker gene set and a test set comprised of expression datasets (biosets) with known effects on STAT5b function were evaluated using a rank-based test (the Running Fisher algorithm). Using a similarity p-value ≤ 10(-4), the test achieved a balanced accuracy of 99% and 97% for detection of STAT5b activation or STAT5b suppression, respectively. The STAT5b biomarker gene set was then used to identify factors that activate (masculinize) or suppress (feminize) STAT5b function in an annotated mouse liver and primary hepatocyte gene expression compendium of ~1,850 datasets. Disruption of GH-regulated STAT5b is a common phenomenon in liver in vivo, with 5% and 29% of the male datasets, and 11% and 13% of the female datasets, associated with masculinization or feminization, respectively. As expected, liver STAT5b activation/masculinization occurred at puberty and suppression/feminization occurred during aging and in mutant mice with defects in GH signaling. A total of 70 genes were identified that have effects on STAT5b activation in genetic models in which the gene was inactivated or overexpressed. Other factors that affected liver STAT5b function were shown to include fasting, caloric restriction and infections. Together, these findings identify diverse factors that perturb the hypothalamo

  7. Clinicopathological significance of STAT4 in hepatocellular carcinoma and its effect on cell growth and apoptosis

    PubMed Central

    Li, Jianjun; Liang, Lu; Liu, Yongru; Luo, Yihuan; Liang, Xiaona; Luo, Dianzhong; Feng, Zhenbo; Dang, Yiwu; Yang, Lihua; Chen, Gang

    2016-01-01

    Background Recent studies showed that signal transducer and activator of transcription 4 (STAT4) was downregulated in hepatocellular carcinoma (HCC) tissues. However, the role of STAT4 in HCC is still unknown. The aim of this study is to explore the association between STAT4 expression and other clinicopathological features in HCC and to test the effect of STAT4 on cell growth and apoptosis in vitro. Methods STAT4 was evaluated by immunohistochemistry in 171 HCC and corresponding paraneoplastic liver, 37 cirrhosis, and 33 normal liver tissues. Association between STAT4 and clinicopathological parameters was analyzed. Meta-analysis on STAT4 in cancer was performed. The effect of STAT4 small interfering RNA (siRNA) on cell growth and cell apoptosis was also detected. Results Positive rate of STAT4 was 29.2% (50/171) in HCC tissues, 53.2% (91/171) in paraneoplastic liver tissues, 64.9% (24/37) in cirrhosis tissues, and 72.7% (24/33) in normal liver tissues. STAT4 was upregulated in younger patients who were female, with single tumor node, early TNM stage, without portal vein tumor embolus, and α-fetoprotein (AFP)-positive tumors compared with the groups comprising older patients, males, and those with multiple tumor nodes, advanced TNM stage, with portal vein tumor embolus, and AFP negative tumors. Meta-analysis showed STAT4 was correlated with TNM stage (OR =0.50, 95% CI =0.30, 0.83, P=0.008) and age (OR =0.58, 95% CI =0.38, 0.95, P=0.032) in malignant tissues, and with AFP level (OR =1.76, 95% CI =1.06, 2.94, P=0.03) in HCC. STAT4 siRNA promoted growth and suppressed apoptosis of HepG2 cells. Conclusion STAT4 might play a vital role in development of HCC, via influencing cell growth and apoptosis, as a tumor suppressor. PMID:27051307

  8. STATs: An Old Story, Yet Mesmerizing

    PubMed Central

    Abroun, Saeid; Saki, Najmaldin; Ahmadvand, Mohammad; Asghari, Farahnaz; Salari, Fatemeh; Rahim, Fakher

    2015-01-01

    Signal transducers and activators of transcription (STATs) are cytoplasmic transcription factors that have a key role in cell fate. STATs, a protein family comprised of seven members, are proteins which are latent cytoplasmic transcription factors that convey signals from the cell surface to the nucleus through activation by cytokines and growth factors. The signaling pathways have diverse biological functions that include roles in cell differentiation, proliferation, development, apoptosis, and inflammation which place them at the center of a very active area of research. In this review we explain Janus kinase (JAK)/STAT signaling and focus on STAT3, which is transient from cytoplasm to nucleus after phosphorylation. This procedure controls fundamental biological processes by regulating nuclear genes controlling cell proliferation, survival, and development. In some hematopoietic disorders and cancers, overexpression and activation of STAT3 result in high proliferation, suppression of cell differentiation and inhibition of cell maturation. This article focuses on STAT3 and its role in malignancy, in addition to the role of microRNAs (miRNAs) on STAT3 activation in certain cancers. PMID:26464811

  9. The role of STAT3 in autophagy

    PubMed Central

    You, Liangkun; Wang, Zhanggui; Li, Hongsen; Shou, Jiawei; Jing, Zhao; Xie, Jiansheng; Sui, Xinbing; Pan, Hongming; Han, Weidong

    2015-01-01

    Autophagy is an evolutionarily conserved process in eukaryotes that eliminates harmful components and maintains cellular homeostasis in response to a series of extracellular insults. However, these insults may trigger the downstream signaling of another prominent stress responsive pathway, the STAT3 signaling pathway, which has been implicated in multiple aspects of the autophagic process. Recent reports further indicate that different subcellular localization patterns of STAT3 affect autophagy in various ways. For example, nuclear STAT3 fine-tunes autophagy via the transcriptional regulation of several autophagy-related genes such as BCL2 family members, BECN1, PIK3C3, CTSB, CTSL, PIK3R1, HIF1A, BNIP3, and microRNAs with targets of autophagy modulators. Cytoplasmic STAT3 constitutively inhibits autophagy by sequestering EIF2AK2 as well as by interacting with other autophagy-related signaling molecules such as FOXO1 and FOXO3. Additionally, the mitochondrial translocation of STAT3 suppresses autophagy induced by oxidative stress and may effectively preserve mitochondria from being degraded by mitophagy. Understanding the role of STAT3 signaling in the regulation of autophagy may provide insight into the classic autophagy model and also into cancer therapy, especially for the emerging targeted therapy, because a series of targeted agents execute antitumor activities via blocking STAT3 signaling, which inevitably affects the autophagy pathway. Here, we review several of the representative studies and the current understanding in this particular field. PMID:25951043

  10. The role of STAT3 in autophagy.

    PubMed

    You, Liangkun; Wang, Zhanggui; Li, Hongsen; Shou, Jiawei; Jing, Zhao; Xie, Jiansheng; Sui, Xinbing; Pan, Hongming; Han, Weidong

    2015-01-01

    Autophagy is an evolutionarily conserved process in eukaryotes that eliminates harmful components and maintains cellular homeostasis in response to a series of extracellular insults. However, these insults may trigger the downstream signaling of another prominent stress responsive pathway, the STAT3 signaling pathway, which has been implicated in multiple aspects of the autophagic process. Recent reports further indicate that different subcellular localization patterns of STAT3 affect autophagy in various ways. For example, nuclear STAT3 fine-tunes autophagy via the transcriptional regulation of several autophagy-related genes such as BCL2 family members, BECN1, PIK3C3, CTSB, CTSL, PIK3R1, HIF1A, BNIP3, and microRNAs with targets of autophagy modulators. Cytoplasmic STAT3 constitutively inhibits autophagy by sequestering EIF2AK2 as well as by interacting with other autophagy-related signaling molecules such as FOXO1 and FOXO3. Additionally, the mitochondrial translocation of STAT3 suppresses autophagy induced by oxidative stress and may effectively preserve mitochondria from being degraded by mitophagy. Understanding the role of STAT3 signaling in the regulation of autophagy may provide insight into the classic autophagy model and also into cancer therapy, especially for the emerging targeted therapy, because a series of targeted agents execute antitumor activities via blocking STAT3 signaling, which inevitably affects the autophagy pathway. Here, we review several of the representative studies and the current understanding in this particular field. PMID:25951043

  11. Targeting constitutively-activated STAT3 in hypoxic ovarian cancer, using a novel STAT3 inhibitor

    PubMed Central

    McCann, Georgia A.; Naidu, Shan; Rath, Kellie S.; Bid, Hemant K.; Tierney, Brent J.; Suarez, Adrian; Varadharaj, Saradhadevi; Zhang, Jianying; Hideg, Kálmán; Houghton, Peter; Kuppusamy, Periannan; Cohn, David E.; Selvendiran, Karuppaiyah

    2014-01-01

    Tumor hypoxia, a feature of many solid tumors including ovarian cancer, is associated with resistance to therapies. We previously demonstrated that hypoxic exposure results in increased expression of phosphorylated signal transducer and activator of transcription 3 (pSTAT3). We hypothesized the activation of STAT3 could lead to chemotherapeutic resistance in ovarian cancer cells in hypoxic conditions. In this study, we demonstrate the level of pSTAT3 Tyr705 is increased in the hypoxic regions of human epithelial ovarian cancer (EOC) specimens, as determined by HIF-1α and CD-31 staining. In vitro mutagenesis studies proved that pSTAT3 Tyr705 is necessary for cell survival and proliferation under hypoxic conditions. In addition, we show that S1PR1, a regulator of STAT3 transcription via the JAK/STAT pathway, is highly expressed in hypoxic ovarian cancer cells (HOCCs). Knock down of S1PR1 in HOCCs reduced pSTAT3 Tyr705 levels and was associated with decreased cell survival. Treatment of HOCCs with the STAT3 inhibitor HO-3867 resulted in a rapid and dramatic decrease in pSTAT3 Tyr705 levels as a result of ubiquitin proteasome degradation. STAT3-target proteins Bcl-xL, cyclin D2 and VEGF showed similar decreases in HO-3867 treated cells. Taken together, these findings suggest that activation of STAT3 Tyr705 promotes cell survival and proliferation in HOCCs, and that S1PR1 is involved in the initiation of STAT3 activation. Targeting hypoxia-mediated STAT3 activation represents a therapeutic option for ovarian cancer and other solid tumors. PMID:25594014

  12. Monoclonal Antibodies Specific for STAT3β Reveal Its Contribution to Constitutive STAT3 Phosphorylation in Breast Cancer

    PubMed Central

    Bharadwaj, Uddalak; Kasembeli, Moses M.; Eckols, T. Kris; Kolosov, Mikhail; Lang, Paul; Christensen, Kurt; Edwards, Dean P.; Tweardy, David J.

    2014-01-01

    Since its discovery in mice and humans 19 years ago, the contribution of alternatively spliced Stat3, Stat3β, to the overall functions of Stat3 has been controversial. Tyrosine-phosphorylated (p) Stat3β homodimers are more stable, bind DNA more avidly, are less susceptible to dephosphorylation, and exhibit distinct intracellular dynamics, most notably markedly prolonged nuclear retention, compared to pStat3α homodimers. Overexpression of one or the other isoform in cell lines demonstrated that Stat3β acted as a dominant-negative of Stat3α in transformation assays; however, studies with mouse strains deficient in one or the other isoform indicated distinct contributions of Stat3 isoforms to inflammation. Current immunological reagents cannot differentiate Stat3β proteins derived from alternative splicing vs. proteolytic cleavage of Stat3α. We developed monoclonal antibodies that recognize the 7 C-terminal amino acids unique to Stat3β (CT7) and do not cross-react with Stat3α. Immunoblotting studies revealed that levels of Stat3β protein, but not Stat3α, in breast cancer cell lines positively correlated with overall pStat3 levels, suggesting that Stat3β may contribute to constitutive Stat3 activation in this tumor system. The ability to unambiguously discriminate splice alternative Stat3β from proteolytic Stat3β and Stat3α will provide new insights into the contribution of Stat3β vs. Stat3α to oncogenesis, as well as other biological and pathological processes. PMID:25268166

  13. Employing Introductory Statistics Students at "Stats Dairy"

    ERIC Educational Resources Information Center

    Keeling, Kellie

    2011-01-01

    To combat students' fear of statistics I employ my students at a fictional company, Stats Dairy, run by cows. Almost all examples used in the class notes, exercises, humour and exams use data "collected" from this company.

  14. JAKs and STATs in invertebrate model organisms.

    PubMed

    Dearolf, C R

    1999-09-01

    Invertebrate organisms provide systems to elucidate the developmental roles of Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathways, thereby complementing research conducted with mammalian cells and animals. Components of the JAK/STAT protein pathway have been identified and characterized in the fruit fly Drosophila melanogaster and the cellular slime mold Dictyostelium discoideum. This review summarizes the molecular and genetic data obtained from these model organisms. In particular, a Drosophila JAK/STAT pathway regulates normal segmentation, cell proliferation, and differentiation, and hyperactivation of the pathway leads to tumor formation and leukemia-like defects. A Dictyostelium STAT regulates the development of stalk cells during the multicellular part of the life cycle. Future research utilizing these organisms should continue to provide insights into the roles and regulation of these proteins and their signaling pathways. PMID:10526575

  15. The JAK-STAT Pathway at Twenty

    PubMed Central

    Stark, George R.; Darnell, James E.

    2014-01-01

    We look back on the discoveries that the tyrosine kinases TYK2 and JAK1 and the transcription factors STAT1, STAT2, and IRF9 are required for the cellular response to type I interferons. This initial description of the JAK-STAT pathway led quickly to additional discoveries that type II interferons and many other cytokines signal through similar mechanisms. This well-understood pathway now serves as a paradigm showing how information from protein-protein contacts at the cell surface can be conveyed directly to genes in the nucleus. We also review recent work on the STAT proteins showing the importance of several different posttranslational modifications, including serine phosphorylation, acetylation, methylation, and sumoylation. These remarkably proficient proteins also provide noncanonical functions in transcriptional regulation and they also function in mitochondrial respiration and chromatin organization in ways that may not involve transcription at all. PMID:22520844

  16. Lead isotopic studies of lunar soils - Their bearing on the time scale of agglutinate formation

    NASA Technical Reports Server (NTRS)

    Church, S. E.; Tilton, G. R.; Chen, J. H.

    1976-01-01

    Fines (smaller than 75 microns) and bulk soil were studied to analyze loss of volatile lead; losses of the order of 10% to 30% radiogenic lead during the production of agglutinates are assessed. Lead isotope data from fine-agglutinate pairs are analyzed for information on the time scale of micrometeorite bombardment, from the chords generated by the data in concordia diagrams. Resulting mean lead loss ages were compared to spallogenic gas exposure ages for all samples. Labile parentless radiogenic Pb residing preferentially on or in the fines is viewed as possibly responsible for aberrant lead loss ages. Bulk soils plot above the concordia curve (in a field of excess radiogenic Pb) for all samples with anomalous ages.

  17. Nanomolar-Potency Small Molecule Inhibitor of STAT5 Protein

    PubMed Central

    2014-01-01

    We herein report the design and synthesis of the first nanomolar binding inhibitor of STAT5 protein. Lead compound 13a, possessing a phosphotyrosyl-mimicking salicylic acid group, potently and selectively binds to STAT5 over STAT3, inhibits STAT5–SH2 domain complexation events in vitro, silences activated STAT5 in leukemic cells, as well as STAT5′s downstream transcriptional targets, including MYC and MCL1, and, as a result, leads to apoptosis. We believe 13a represents a useful probe for interrogating STAT5 function in cells as well as being a potential candidate for advanced preclinical trials. PMID:25419444

  18. Novel platelet-agglutinating protein from a thrombotic thrombocytopenic purpura plasma.

    PubMed Central

    Siddiqui, F A; Lian, E C

    1985-01-01

    A novel platelet-agglutinating protein (PAP) was purified approximately 2,000-fold from the plasma of a patient with thrombotic thrombocytopenic purpura (TTP) by ammonium sulfate fractionation, DEAE-Sephacel and concanavalin A-Sepharose chromatographies. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with and without reduction, this preparation revealed a major protein band with a molecular weight of 37,000, and a minor band with a molecular weight of 32,000-34,000. After elution from the gel, only the 37,000-mol wt protein corresponding to the major band induced the platelet agglutination. When four normal plasmas and the recovery plasma from the same TTP patient were subjected to the similar purification steps, the 37,000-mol wt major band was absent. The 125I-PAP bound to the platelets in a concentration-dependent manner. The platelet agglutination induced by PAP was not inhibited by hirudin, heparin in the presence of antithrombin III, phenylmethylsulfonyl fluoride, apyrase, aspirin, or prostaglandin I2. However, it was inhibited by IgG from normal adults and from the same TTP patient after recovery. The anti-37,000-mol wt PAP antiserum prepared in the rabbit formed a single precipitin line against the highly purified PAP. Using this antiserum in the Western immunoblotting, the 37,000-mol wt protein band was found in the three TTP plasmas, of which the platelet-agglutinating activity was inhibited by the anti-37,000-mol wt PAP IgG. The 37,000-mol wt immunoprecipitin band was absent in the plasmas obtained from another two TTP patients, two normal subjects, two patients with idiopathic thrombocytopenic purpura, and two patients with disseminated intravascular coagulation. These results suggest that the 37,000-mol wt PAP is present only in certain cases of TTP, and is likely to be responsible for the formation of platelet thrombi in the microcirculation. Images PMID:3932464

  19. Comparison of type 2 and type 6 fimbriae of Bordetella pertussis by using agglutinating monoclonal antibodies.

    PubMed

    Li, Z M; Brennan, M J; David, J L; Carter, P H; Cowell, J L; Manclark, C R

    1988-12-01

    Two types of fimbriae have been identified on the pathogenic gram-negative organism Bordetella pertussis. Monoclonal antibodies to these fimbriae were produced to better understand the role of fimbriae as serotype-specific agglutinogens and to investigate the antigenic relationship between these fimbriae. Three monoclonal antibodies were identified that specifically agglutinated B. pertussis cells containing the U.S. Reference Factor 2 agglutinogen, and six monoclonal antibodies were produced that agglutinated only those strains containing the U.S. Reference Factor 6 agglutinogen. Indirect immunofluorescence studies and immunogold electron microscopy demonstrated that these monoclonal antibodies bind to an outer membrane component on serotype-specific strains of B. pertussis. All of the monoclonal antibodies reacted with native or partially assembled type-specific fimbriae but not with monomeric fimbrial subunits as indicated by Western blot (immunoblot) analysis. The fimbrial agglutinogens recognized by the monoclonal antibodies were also uniquely reactive with either U.S. Reference Factor 2 or 6 antiserum (Eldering agglutinogen 2 or 6 polyclonal antiserum) in an indirect ELISA. No cross-reactivity of the monoclonal antibodies with the unrelated fimbriae was observed in any of the comparative immunological studies. Some of the monoclonal antibodies agglutinated certain strains of B. bronchiseptica, suggesting that this closely related species can contain antigenically similar fimbriae. These monoclonal antibodies should prove useful for further structural and functional analysis of Bordetella fimbriae and for studies on the role that these antigens play in prevention of infection and disease. PMID:2903125

  20. Comparison of type 2 and type 6 fimbriae of Bordetella pertussis by using agglutinating monoclonal antibodies.

    PubMed Central

    Li, Z M; Brennan, M J; David, J L; Carter, P H; Cowell, J L; Manclark, C R

    1988-01-01

    Two types of fimbriae have been identified on the pathogenic gram-negative organism Bordetella pertussis. Monoclonal antibodies to these fimbriae were produced to better understand the role of fimbriae as serotype-specific agglutinogens and to investigate the antigenic relationship between these fimbriae. Three monoclonal antibodies were identified that specifically agglutinated B. pertussis cells containing the U.S. Reference Factor 2 agglutinogen, and six monoclonal antibodies were produced that agglutinated only those strains containing the U.S. Reference Factor 6 agglutinogen. Indirect immunofluorescence studies and immunogold electron microscopy demonstrated that these monoclonal antibodies bind to an outer membrane component on serotype-specific strains of B. pertussis. All of the monoclonal antibodies reacted with native or partially assembled type-specific fimbriae but not with monomeric fimbrial subunits as indicated by Western blot (immunoblot) analysis. The fimbrial agglutinogens recognized by the monoclonal antibodies were also uniquely reactive with either U.S. Reference Factor 2 or 6 antiserum (Eldering agglutinogen 2 or 6 polyclonal antiserum) in an indirect ELISA. No cross-reactivity of the monoclonal antibodies with the unrelated fimbriae was observed in any of the comparative immunological studies. Some of the monoclonal antibodies agglutinated certain strains of B. bronchiseptica, suggesting that this closely related species can contain antigenically similar fimbriae. These monoclonal antibodies should prove useful for further structural and functional analysis of Bordetella fimbriae and for studies on the role that these antigens play in prevention of infection and disease. Images PMID:2903125

  1. [Diagnosis of chronic leptospirosis, comparison between the microscopic agglutination and three confirmatory diagnostic techniques].

    PubMed

    Velasco-Castrejón, Oscar; Rivas Sánchez, Beatriz; Espinoza Hernández, Jacqueline; Martínez Hernández, Enrique

    2007-01-01

    In spite of the fact that the serology and, particularly, the microscopic agglutination technique are the most recommended methods to diagnose leptospirosis, they frequently fail in the diagnosis of individual cases and in outbreaks, where the diagnosis is frequently made post-mortem by argentic and immunohistochemical impregnation,. These techniques are also unable to diagnose chronic leptospirosis, since the antibody titres are very low (< or = 1:80) in it. Due to this fact, and to the need of a reliable and appropriate lab diagnosis, a comparative study of dark field videorecording, supported by argentic impregnation and immunohistochemistry in blood and urine was conducted against a serology by microscopic agglutination technique in 60 patients with chronic leptospirosis. Dark field videorecording, argentic impregnation, and immunohistochemistry proved to be be much more sensible than the microscopic agglutination technique, in addition to be comparable among themselves. We recommended videorecording to achieve a fast, early, and economical diagnosis, particularly, if we associate it with immunohistochemistry or argentic impregnation. Likewise, in the culture of these samples, 2 strains of 82 % of positive primoculture were obtained, and an electronic microphotography was possible to attain in the peripheral blood of one of the studied cases, which guarantees the study and confirms the existence of chronic leptospirosis. PMID:23427411

  2. “Cherty” stringers in the Barnett Shale are agglutinated foraminifera

    NASA Astrophysics Data System (ADS)

    Milliken, Kitty; Choh, Suk-Joo; Papazis, Petro; Schieber, Jürgen

    2007-06-01

    Masses of microcrystalline quartz are abundant within several lithologies in the Barnett Shale (lower Mississippian) of central Texas. A typical quartz mass is elongated parallel to bedding and contains a central planar microporous structure that suggests collapse of a formerly hollow spheroidal or tubular body. An integrated imaging approach, utilizing transmitted polarized light microscopy, secondary and back-scattered electron imaging, cathodoluminescence imaging, and X-ray mapping reveals these quartz masses to be composed primarily of quartz-cemented silt-size detrital quartz with a minor admixture of detrital Ca-plagioclase and dolomite. Microcrystalline quartz-rich masses in the Barnett Shale are interpreted as agglutinated foraminifera that have been dramatically collapsed during compaction. Locally, a significant portion of the total detrital quartz resides within these biogenic accumulations. This study highlights the potential for using these imaging techniques to investigate agglutinated foraminifera in lithified materials that are not amenable to disaggregation and extraction of three-dimensional specimens. The combined imaging techniques provide an unambiguous view into aspects of skeletal ultrastructure, such as particle size and sorting, that cannot be readily obtained from either conventional light microscopy or SEM. These techniques reveal that agglutinated foraminifers are abundant in several lithologies of the Barnett Shale, pointing to the possibility that application in other organic-rich shales may reveal these organisms to be more widespread than previously recognized. Comparative observations in Devonian shales of the central eastern United States support this prediction.

  3. Distinct roles of STAT3 and STAT5 in the pathogenesis and targeted therapy of breast cancer

    PubMed Central

    Walker, Sarah R.; Xiang, Michael; Frank, David A.

    2013-01-01

    The transcription factors STAT3 and STAT5 play important roles in the regulation of mammary gland function during pregnancy, lactation, and involution. Given that STAT3 and STAT5 regulate genes involved in proliferation and survival, it is not surprising that inappropriate activation of STAT3 and STAT5 occurs commonly in breast cancer. Although these proteins are structurally similar, they have divergent and opposing effects on gene expression and cellular phenotype. Notably, when STAT5 and STAT3 are activated simultaneously, STAT5 has a dominant effect, and leads to decreased proliferation and increased sensitivity to cell death. Similarly, in breast cancer, activation of both STAT5 and STAT3 is associated with longer patient survival than activation of STAT3 alone. Pharmacological inhibitors of STAT3 and STAT5 are being developed for cancer therapy, though understanding the activation state and functional interaction of STAT3 and STAT5 in a patient's tumor may be critical for the optimal use of this strategy. PMID:23531638

  4. 9 CFR 147.6 - Procedure for determining the status of flocks reacting to tests for Mycoplasma gallisepticum...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the microagglutination tests, as reported in the Proceedings, Sixteenth Annual Meeting of the American... agglutination or the serum plate test is negative, the flock qualifies. (2) If the tube agglutination or the serum plate test is positive, the hemaglutination inhibition (HI) test and/or the Serum Plate...

  5. Methylsulfonylmethane suppresses breast cancer growth by down-regulating STAT3 and STAT5b pathways.

    PubMed

    Lim, Eun Joung; Hong, Dae Young; Park, Jin Hee; Joung, Youn Hee; Darvin, Pramod; Kim, Sang Yoon; Na, Yoon Mi; Hwang, Tae Sook; Ye, Sang-Kyu; Moon, Eon-Soo; Cho, Byung Wook; Do Park, Kyung; Lee, Hak Kyo; Park, Taekyu; Yang, Young Mok

    2012-01-01

    Breast cancer is the most aggressive form of all cancers, with high incidence and mortality rates. The purpose of the present study was to investigate the molecular mechanism by which methylsulfonylmethane (MSM) inhibits breast cancer growth in mice xenografts. MSM is an organic sulfur-containing natural compound without any toxicity. In this study, we demonstrated that MSM substantially decreased the viability of human breast cancer cells in a dose-dependent manner. MSM also suppressed the phosphorylation of STAT3, STAT5b, expression of IGF-1R, HIF-1α, VEGF, BrK, and p-IGF-1R and inhibited triple-negative receptor expression in receptor-positive cell lines. Moreover, MSM decreased the DNA-binding activities of STAT5b and STAT3, to the target gene promoters in MDA-MB 231 or co-transfected COS-7 cells. We confirmed that MSM significantly decreased the relative luciferase activities indicating crosstalk between STAT5b/IGF-1R, STAT5b/HSP90α, and STAT3/VEGF. To confirm these findings in vivo, xenografts were established in Balb/c athymic nude mice with MDA-MB 231 cells and MSM was administered for 30 days. Concurring to our in vitro analysis, these xenografts showed decreased expression of STAT3, STAT5b, IGF-1R and VEGF. Through in vitro and in vivo analysis, we confirmed that MSM can effectively regulate multiple targets including STAT3/VEGF and STAT5b/IGF-1R. These are the major molecules involved in tumor development, progression, and metastasis. Thus, we strongly recommend the use of MSM as a trial drug for treating all types of breast cancers including triple-negative cancers. PMID:22485142

  6. The Life Cycle of Entzia, an Agglutinated Foraminifer from the Salt Marshes in Transylvania

    NASA Astrophysics Data System (ADS)

    Kaminski, Michael; Telespan, Andreea; Balc, Ramona; Filipescu, Sorin; Varga, Ildiko; Görög, Agnes

    2013-04-01

    The small salt marshes associated with Miocene salt domes in Transylvania are host to a variety of marine organisms, including communities of halophytic plants as well as an agglutinated foraminifer that is normally found in coastal salt marshes worldwide. Originally described as the species Entzia tetrastoma by Daday (1884), the foraminifer is more widely known by the name Jadammina macrescens (Brady, 1870). Because the genus name Entzia has priority over Jadammina, the valid name of this taxon is Entzia macrescens (Brady, 1870). In 2007, we discovered a living population of Entzia inhabiting a small salt marsh just outside the town of Turda in central Transylvania, only a kilometer from the famous Maria Theresa Salt Mine. This is the first discovery of a living population of Entzia in Transylvania since the species was originally described in 1884. To determine whether or not the specimens we found represent a breeding population, samples were collected from the marsh on a monthly basis over the span of a year. This species can be found among the roots of the halophytic plants, in the uppermost one or two centimeters of the mud. Sediment samples were preserved in Vodka with Rose Bengal to distinguish living and dead specimens, and examined quantitatively. To document the life cycle of the species the following metrics were carried out: test size, abundance, number of chambers, ratio between live and dead specimens, and the diameter of the proloculus. An increase in the mean diameter of specimens was found from October to December. However the mean diameter decreased again in January, which suggests that asexual reproduction had apparently taken place. Small specimens again appeared in March, when sexual reproduction is presumed to have taken place. The median proloculus diameter was smallest in April and May, but the monthly changes in mean proloculus size within the population over the span of a year are not significant. However, specimens with largest

  7. Sleep Loss Activates Cellular Inflammation and Signal Transducer and Activator of Transcription (STAT) Family Proteins in Humans

    PubMed Central

    Irwin, Michael R.; Witarama, Tuff; Caudill, Marissa; Olmstead, Richard; Breen, Elizabeth Crabb

    2014-01-01

    Sleep disturbance and short sleep duration are associated with inflammation and related disorders including cardiovascular disease, arthritis, diabetes mellitus, and certain cancers. This study was undertaken to test the effects of experimental sleep loss on spontaneous cellular inflammation and activation of signal transducer and activator of transcription (STAT) family proteins, which together promote an inflammatory microenvironment. In 24 healthy adults (16 females; 8 males), spontaneous production of IL-6 and TNF in monocytes and spontaneous intranuclear expression of activated STAT1, STAT3, and STAT5 in peripheral blood mononuclear cells (PBMC), monocyte-, and lymphocyte populations were measured in the morning after uninterrupted baseline sleep, partial sleep deprivation (PSD, sleep period from 3 a.m. to 7 a.m.), and recovery sleep. Relative to baseline, spontaneous monocytic expression of IL-6 and TNF-α was significantly greater after PSD (P<0.02) and after recovery sleep (P<0.01). Relative to baseline, spontaneous monocytic expression of activated STAT 1 and STAT 5 was significantly greater after recovery sleep (P<0.007P<0.02, respectively) but not STAT 3 (P=0.09). No changes in STAT1, STAT3, or STAT5 were found in lymphocyte populations. Sleep loss induces activation of spontaneous cellular innate immunity and of STAT family proteins, which together map the dynamics of sleep loss on the molecular signaling pathways that regulate inflammatory and other immune responses. Treatments that target short sleep duration have the potential to constrain inflammation and reduce the risk for inflammatory disorders and some cancers in humans. PMID:25451613

  8. D-penicillamine prevents ram sperm agglutination by reducing the disulphide bonds of a copper-binding sperm protein.

    PubMed

    Leahy, T; Rickard, J P; Aitken, R J; de Graaf, S P

    2016-05-01

    Head-to-head agglutination of ram spermatozoa is induced by dilution in the Tyrode's capacitation medium with albumin, lactate and pyruvate (TALP) and ameliorated by the addition of the thiol d-penicillamine (PEN). To better understand the association and disassociation of ram spermatozoa, we investigated the mechanism of action of PEN in perturbing sperm agglutination. PEN acts as a chelator of heavy metals, an antioxidant and a reducing agent. Chelation is not the main mechanism of action, as the broad-spectrum chelator ethylenediaminetetraacetic acid and the copper-specific chelator bathocuproinedisulfonic acid were inferior anti-agglutination agents compared with PEN. Oxidative stress is also an unlikely mechanism of sperm association, as PEN was significantly more effective in ameliorating agglutination than the antioxidants superoxide dismutase, ascorbic acid, α-tocopherol and catalase. Only the reducing agents cysteine and dl-dithiothreitol displayed similar levels of non-agglutinated spermatozoa at 0 h compared with PEN but were less effective after 3 h of incubation (37 °C). The addition of 10 µM Cu(2+) to 250 µM PEN + TALP caused a rapid reversion of the motile sperm population from a non-agglutinated state to an agglutinated state. Other heavy metals (cobalt, iron, manganese and zinc) did not provoke such a strong response. Together, these results indicate that PEN prevents sperm association by the reduction of disulphide bonds on a sperm membrane protein that binds copper. ADAM proteins are possible candidates, as targeted inhibition of the metalloproteinase domain significantly increased the percentage of motile, non-agglutinated spermatozoa (52.0% ± 7.8) compared with TALP alone (10.6% ± 6.1).Reproduction (2016) 151 1-10. PMID:26860122

  9. JAK/STAT signalling: STAT cannot play with Ken and Barbie.

    PubMed

    Hombría, James Castelli-Gair; Sotillos, Sol

    2006-02-01

    Transcriptional responses to the activation of a signalling pathway are cell-specific. New data show that the sequence-specific transcriptional repressors of the KEN/BCL-6 family play an important role in the selection of STAT targets in vertebrates and invertebrates, indicating that all STAT proteins may share this ancestral mechanism. PMID:16461274

  10. Isolation and Expression Analysis of STAT Members from Synechogobius hasta and Their Roles in Leptin Affecting Lipid Metabolism.

    PubMed

    Wu, Kun; Tan, Xiao-Ying; Wei, Chuan-Chuan; You, Wen-Jing; Zhuo, Mei-Qin; Song, Yu-Feng

    2016-01-01

    Signal transducers and activators of transcription proteins (STATs) act as important mediators in multiple biological processes induced by a large number of cytokines. In the present study, full-length cDNA sequences of seven STAT members, including some splicing variants different from those in mammals, were obtained from Synechogobius hasta. The phylogenetic analysis revealed that the seven STAT members were derived from paralogous genes that might have arisen by whole genome duplication (WGD) events during vertebrate evolution. All of these members share similar domain structure compared with those of mammals, and were widely expressed across the tested tissues (brain, gill, heart, intestine, liver, muscle and spleen), but at variable levels. Incubation in vitro of recombinant human leptin changed the intracellular triglyceride (TG) content and mRNA levels of several STATs members, as well as expressions and activities of genes involved in lipid metabolism. Furthermore, Tyrphostin B42 (AG490), a specific inhibitor of the Janus Kinase 2(JAK2)-STAT pathway, partially reversed leptin-induced change on STAT3 and its two spliced isoforms expression, as well as expressions and activities of genes involved in lipid metabolism. As a consequence, the decrease of TG content was also reversed. Thus, our study suggests that STAT3 is the requisite for the leptin signal and the activation of the STAT3 member may account for the leptin-induced changes in lipid metabolism in S. hasta. PMID:27011172

  11. Isolation and Expression Analysis of STAT Members from Synechogobius hasta and Their Roles in Leptin Affecting Lipid Metabolism

    PubMed Central

    Wu, Kun; Tan, Xiao-Ying; Wei, Chuan-Chuan; You, Wen-Jing; Zhuo, Mei-Qin; Song, Yu-Feng

    2016-01-01

    Signal transducers and activators of transcription proteins (STATs) act as important mediators in multiple biological processes induced by a large number of cytokines. In the present study, full-length cDNA sequences of seven STAT members, including some splicing variants different from those in mammals, were obtained from Synechogobius hasta. The phylogenetic analysis revealed that the seven STAT members were derived from paralogous genes that might have arisen by whole genome duplication (WGD) events during vertebrate evolution. All of these members share similar domain structure compared with those of mammals, and were widely expressed across the tested tissues (brain, gill, heart, intestine, liver, muscle and spleen), but at variable levels. Incubation in vitro of recombinant human leptin changed the intracellular triglyceride (TG) content and mRNA levels of several STATs members, as well as expressions and activities of genes involved in lipid metabolism. Furthermore, Tyrphostin B42 (AG490), a specific inhibitor of the Janus Kinase 2(JAK2)-STAT pathway, partially reversed leptin-induced change on STAT3 and its two spliced isoforms expression, as well as expressions and activities of genes involved in lipid metabolism. As a consequence, the decrease of TG content was also reversed. Thus, our study suggests that STAT3 is the requisite for the leptin signal and the activation of the STAT3 member may account for the leptin-induced changes in lipid metabolism in S. hasta. PMID:27011172

  12. Progesterone-induced blocking factor activates STAT6 via binding to a novel IL-4 receptor.

    PubMed

    Kozma, Noemi; Halasz, Melinda; Polgar, Beata; Poehlmann, Tobias G; Markert, Udo R; Palkovics, Tamas; Keszei, Marton; Par, Gabriella; Kiss, Katalin; Szeberenyi, Jozsef; Grama, Laszlo; Szekeres-Bartho, Julia

    2006-01-15

    Progesterone-induced blocking factor (PIBF) induces Th2-dominant cytokine production. Western blotting and EMSA revealed phosphorylation as well as nuclear translocation of STAT6 and inhibition of STAT4 phosphorylation in PIBF-treated cells. The silencing of STAT6 by small interfering RNA reduced the cytokine effects. Because the activation of the STAT6 pathway depends on the ligation of IL-4R, we tested the involvement of IL-4R in PIBF-induced STAT6 activation. Although PIBF does not bind to IL-4R, the blocking of the latter with an Ab abolished PIBF-induced STAT6 activation, whereas the blocking of the IL-13R had no effect. PIBF activated suppressor of cytokine signaling-3 and inhibited IL-12-induced suppressor of cytokine signaling-1 activation. The blocking of IL-4R counteracted all the described effects, suggesting that the PIBF receptor interacts with IL-4R alpha-chain, allowing PIBF to activate the STAT6 pathway. PIBF did not phosphorylate Jak3, suggesting that the gamma-chain is not needed for PIBF signaling. Confocal microscopic analysis revealed a colocalization and at 37 degrees C a cocapping of the FITC PIBF-activated PIBF receptor and PE anti-IL-4R-labeled IL-4R. After the digestion of the cells with phosphatidylinositol-specific phospholipase C, the STAT6-activating effect of PIBF was lost, whereas that of IL-4 remained unaltered. These data suggest the existence of a novel type of IL-4R composed of the IL-4R alpha-chain and the GPI-anchored PIBF receptor. PMID:16393965

  13. Effective targeting of STAT5-mediated survival in myeloproliferative neoplasms using ABT-737 combined with rapamycin

    PubMed Central

    Li, Geqiang; Miskimen, Kristy L.; Wang, Zhengqi; Xie, Xiu Yan; Tse, William; Gouilleux, Fabrice; Moriggl, Richard; Bunting, Kevin D.

    2010-01-01

    Signal transducer and activator of transcription-5 (STAT5) is a critical transcription factor for normal hematopoiesis and its sustained activation is associated with hematologic malignancy. A persistently active mutant of STAT5 (STAT5aS711F) associates with Grb2 associated binding protein 2 (Gab2) in myeloid leukemias and promotes growth in vitro through AKT activation. Here we have retrovirally transduced wild-type or Gab2−/− mouse bone marrow cells expressing STAT5aS711F and transplanted into irradiated recipient mice to test an in vivo myeloproliferative disease (MPD) model. To target Gab2-independent AKT/mTOR activation, wild-type mice were treated separately with rapamycin. In either case, mice lacking Gab2 or treated with rapamycin displayed attenuated myeloid hyperplasia and modestly improved survival, but the effects were not cytotoxic and were reversible. To improve upon this approach, in vitro targeting of STAT5-mediated AKT/mTOR using rapamycin was combined with inhibition of the STAT5 direct target genes bcl-2 and bcl-XL using ABT-737. Striking synergy with both drugs was observed in mouse BaF3 cells expressing STAT5aS711F, TEL-JAK2, or BCR-ABL and in the relatively single agent-resistant human BCR-ABL positive K562 cell line. Therefore, targeting distinct STAT5 mediated survival signals, e.g. bcl-2/bcl-XL and AKT/mTOR may be an effective therapeutic approach for human myeloproliferative neoplasms. PMID:20535152

  14. Weapons of STAT destruction. Interferon evasion by paramyxovirus V protein.

    PubMed

    Horvath, Curt M

    2004-12-01

    The signal transducer and activator of transcription (STAT) family of proteins function to activate gene transcription downstream of myriad cytokine and growth factor signals. The prototype STAT proteins, STAT1 and STAT2, are required for innate and adaptive antimicrobial immune responses that result from interferon signal transduction. While many viruses have evolved the ability to avoid these antiviral cytokines, the Paramyxoviruses are distinct in their abilities to interfere directly with STAT proteins. Individual paramyxovirus species differ greatly in their precise mechanism of STAT signaling evasion, but a virus-encoded protein called V plays a central role in this process. The theme of V-dependent interferon evasion and its variations provide significant insights into virus-host interactions and viral immune evasion that can help define targets for antiviral drug design. Exposure of the viral weapons of STAT destruction may also be instructive for application to STAT-directed therapeutics for diseases characterized by STAT hyperactivity. PMID:15606749

  15. A time- and dose-dependent STAT1 expression system

    PubMed Central

    Leitner, Nicole R; Strobl, Birgit; Bokor, Marion; Painz, Ronald; Kolbe, Thomas; Rülicke, Thomas; Müller, Mathias; Karaghiosoff, Marina

    2006-01-01

    Background The signal transducer and activator of transcription (STAT) family of transcription factors mediates a variety of cytokine dependent gene regulations. STAT1 has been mainly characterized by its role in interferon (IFN) type I and II signaling and STAT1 deficiency leads to high susceptibility to several pathogens. For fine-tuned analysis of STAT1 function we established a dimerizer-inducible system for STAT1 expression in vitro and in vivo. Results The functionality of the dimerizer-induced STAT1 system is demonstrated in vitro in mouse embryonic fibroblasts and embryonic stem cells. We show that this two-vector based system is highly inducible and does not show any STAT1 expression in the absence of the inducer. Reconstitution of STAT1 deficient cells with inducible STAT1 restores IFNγ-mediated gene induction, antiviral responses and STAT1 activation remains dependent on cytokine stimulation. STAT1 expression is induced rapidly upon addition of dimerizer and expression levels can be regulated in a dose-dependent manner. Furthermore we show that in transgenic mice STAT1 can be induced upon stimulation with the dimerizer, although only at low levels. Conclusion These results prove that the dimerizer-induced system is a powerful tool for STAT1 analysis in vitro and provide evidence that the system is suitable for the use in transgenic mice. To our knowledge this is the first report for inducible STAT1 expression in a time- and dose-dependent manner. PMID:17184522

  16. Characterization of Treponema pallidum Particle Agglutination Assay-Negative Sera following Screening by Treponemal Total Antibody Enzyme Immunoassays ▿

    PubMed Central

    Maple, P. A. C.; Ratcliffe, D.; Smit, E.

    2010-01-01

    Following a laboratory audit, a significant number of Treponema pallidum particle agglutination assay (TPPA)-negative sera were identified when TPPA was used as a confirmatory assay of syphilis enzyme immunoassay (EIA) screening-reactive sera (SSRS). Sera giving such discrepant results were further characterized to assess their significance. A panel of 226 sera was tested by the Abbott Murex ICE Syphilis EIA and then by the Newmarket Syphilis EIA II. TPPA testing was performed on 223 sera. Further testing by the Venereal Disease Research Laboratory (VDRL) test, the Mercia Syphilis IgM EIA, the fluorescent treponemal antibody (FTA-ABS) assay, and INNO-LIA immunoblotting was undertaken in discrepant cases. One hundred eighty-seven of 223 (83.8%) SSRS were TPPA reactive, while 26 (11.6%) sera which were reactive in both the ICE and Newmarket EIAs were nonreactive by TPPA. The majority (68%) of the TPPA-discrepant sera were from HIV-positive patients and did not represent early acute cases, based on previous or follow-up samples, which were available for 22/26 samples. FTA-ABS testing was performed on 24 of these sera; 14 (58.3%) were FTA-ABS positive, and 10 (41.7%) were FTA-ABS negative. Twenty-one of these 26 sera were tested by INNO-LIA, and an additional 4 FTA-ABS-negative samples were positive. In this study, significant numbers (18/26) of SSRS- and TPPA-negative sera were shown by further FTA-ABS and LIA (line immunoblot assay) testing to be positive. The reason why certain sera are negative by TPPA but reactive by treponemal EIA and other syphilis confirmatory assays is not clear, and these initial findings should be further explored. PMID:20844087

  17. Granulin, a novel STAT3-interacting protein, enhances STAT3 transcriptional function and correlates with poorer prognosis in breast cancer

    PubMed Central

    Yeh, Jennifer E.; Kreimer, Simion; Walker, Sarah R.; Emori, Megan M.; Krystal, Hannah; Richardson, Andrea; Ivanov, Alexander R.; Frank, David A.

    2015-01-01

    Since the neoplastic phenotype of a cell is largely driven by aberrant gene expression patterns, increasing attention has been focused on transcription factors that regulate critical mediators of tumorigenesis such as signal transducer and activator of transcription 3 (STAT3). As proteins that interact with STAT3 may be key in addressing how STAT3 contributes to cancer pathogenesis, we took a proteomics approach to identify novel STAT3-interacting proteins. We performed mass spectrometry-based profiling of STAT3-containing complexes from breast cancer cells that have constitutively active STAT3 and are dependent on STAT3 function for survival. We identified granulin (GRN) as a novel STAT3-interacting protein that was necessary for both constitutive and maximal leukemia inhibitory factor (LIF)induced STAT3 transcriptional activity. GRN enhanced STAT3 DNA binding and also increased the time-integrated amount of LIF-induced STAT3 activation in breast cancer cells. Furthermore, silencing GRN neutralized STAT3-mediated tumorigenic phenotypes including viability, clonogenesis, and migratory capacity. In primary breast cancer samples, GRN mRNA levels were positively correlated with STAT3 gene expression signatures and with reduced patient survival. These studies identify GRN as a functionally important STAT3-interacting protein that may serve as an important prognostic biomarker and potential therapeutic target in breast cancer. PMID:26000098

  18. Overexpression of STAT3/pSTAT3 was associated with poor prognosis in gastric cancer: a meta-analysis

    PubMed Central

    He, Shaozhong; Liao, Guixiang; Liu, Yungen; Huang, Liling; Kang, Mafei; Chen, Longhua

    2015-01-01

    Signal transducer and activator of transcription 3 (STAT3) and phospho-STAT3 (pSTAT3) play important roles in the development of gastric cancer. STAT3 is often associated with cell survival, proliferation, and transformation. The prognostic value of STAT3/pSTAT3 in patients with gastric cancer remains controversial in numerous published studies. The aim of this study was to summarize recent findings relevant to the prognostic role of STAT3 and pSTAT3 in patients with gastric cancer. A meta-analysis was performed by searching Web of Knowledge, EMBASE, and PubMed to identify studies on the prognostic impact of STAT3/pSTAT3 in gastric cancers in August 2014. In all, 10 studies were included in the analysis. Data were collected for comparing survival rates in patients with high STAT3 levels compared to those with low levels. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. Sensitivity analysis was conducted, and publication bias was evaluated. Eventually, 1667 cases of gastric cancer were subjected to the final analysis. Among patients with gastric cancer, poor survival was predicted by higher expressions of STAT3 (HR=2.30; 95% CI=1.13-4.68; P=0.02) and pSTAT3 (HR=1.75; 95% CI=1.17-2.61; P=0.006). Moreover, overexpression of STAT3 was associated with poor tumor stage. Additionally, our analysis did not show any statistically significant effect of publication bias regarding STAT3 or pSTAT3. The results of this meta-analysis demonstrated that overexpression of STAT3 and pSTAT3 was associated with poor prognosis in gastric cancer. PMID:26884913

  19. Activation of transcription factors STAT1 and STAT5 in the mouse median eminence after systemic ciliary neurotrophic factor administration.

    PubMed

    Severi, Ilenia; Senzacqua, Martina; Mondini, Eleonora; Fazioli, Francesca; Cinti, Saverio; Giordano, Antonio

    2015-10-01

    Exogenously administered ciliary neurotrophic factor (CNTF) causes weight loss in obese rodents and humans through leptin-like activation of the Jak-STAT3 signaling pathway in hypothalamic arcuate neurons. Here we report for the first time that 40min after acute systemic treatment, rat recombinant CNTF (intraperitoneal injection of 0.3mg/kg of body weight) induced nuclear translocation of the tyrosine-phosphorylated forms of STAT1 and STAT5 in the mouse median eminence and other circumventricular organs, including the vascular organ of the lamina terminalis and the subfornical organ. In the tuberal hypothalamus of treated mice, specific nuclear immunostaining for phospo-STAT1 and phospho-STAT5 was detected in ependymal cells bordering the third ventricle floor and lateral recesses, and in median eminence cells. Co-localization studies documented STAT1 and STAT5 activation in median eminence β-tanycytes and underlying radial glia-like cells. A few astrocytes in the arcuate nucleus responded to CNTF by STAT5 activation. The vast majority of median eminence tanycytes and radial glia-like cells showing phospho-STAT1 and phospho-STAT5 immunoreactivity were also positive for phospho-STAT3. In contrast, STAT3 was the sole STAT isoform activated by CNTF in arcuate nucleus and median eminence neurons. Finally, immunohistochemical evaluation of STAT activation 20, 40, 80, and 120min from the injection demonstrated that cell activation was accompanied by c-Fos expression. Collectively, our findings show that CNTF activates STAT3, STAT1, and STAT5 in vivo. The distinctive activation pattern of these STAT isoforms in the median eminence may disclose novel targets and pathways through which CNTF regulates food intake. PMID:26133794

  20. Signal transducers and activators of transcription 3 (STAT3) inhibits transcription of the inducible nitric oxide synthase gene by interacting with nuclear factor kappaB.

    PubMed Central

    Yu, Zhiyuan; Zhang, Wenzheng; Kone, Bruce C

    2002-01-01

    Prolific generation of NO by inducible nitric oxide synthase (iNOS) can cause unintended injury to host cells during glomerulonephritis and other inflammatory diseases. While much is known about the mechanisms of iNOS induction, few transcriptional repressors have been found. We explored the role of signal transducers and activators of transcription 3 (STAT3) proteins in interleukin (IL)-1beta- and lipopolysaccharide (LPS)+interferon (IFN)-gamma-mediated iNOS induction in murine mesangial cells. Both stimuli induced rapid phosphorylation of STAT3 and sequence-specific STAT3 DNA-binding activity. Supershift assays with a STAT3 element probe demonstrated that nuclear factor kappaB (NF-kappaB) p65 and p50 complexed with STAT3 in the DNA-protein complex. The direct interaction of STAT3 and NF-kappaB p65 was verified in vivo by co-immunoprecipitation and in vitro by pull-down assays with glutathione S-transferase-NF-kappaB p65 fusion protein and in vitro -translated STAT3alpha. Overexpression of STAT3 dramatically inhibited IL-1beta- or LPS+IFN-gamma-mediated induction of iNOS promoter-luciferase constructs that contained the wild-type iNOS promoter or ones harbouring mutated STAT-binding elements. In tests of indirect inhibitory effects of STAT3, overexpression of STAT3 dramatically inhibited the activity of an NF-kappaB-dependent promoter devoid of STAT-binding elements without affecting NF-kappaB DNA-binding activity. Thus STAT3, via direct interactions with NF-kappaB p65, serves as a dominant-negative inhibitor of NF-kappaB activity to suppress indirectly cytokine induction of the iNOS promoter in mesangial cells. These results provide a new model for the termination of NO production by activated iNOS following exposure to pro-inflammatory stimuli. PMID:12057007

  1. Introducing StatHand: A Cross-Platform Mobile Application to Support Students' Statistical Decision Making.

    PubMed

    Allen, Peter J; Roberts, Lynne D; Baughman, Frank D; Loxton, Natalie J; Van Rooy, Dirk; Rock, Adam J; Finlay, James

    2016-01-01

    Although essential to professional competence in psychology, quantitative research methods are a known area of weakness for many undergraduate psychology students. Students find selecting appropriate statistical tests and procedures for different types of research questions, hypotheses and data types particularly challenging, and these skills are not often practiced in class. Decision trees (a type of graphic organizer) are known to facilitate this decision making process, but extant trees have a number of limitations. Furthermore, emerging research suggests that mobile technologies offer many possibilities for facilitating learning. It is within this context that we have developed StatHand, a free cross-platform application designed to support students' statistical decision making. Developed with the support of the Australian Government Office for Learning and Teaching, StatHand guides users through a series of simple, annotated questions to help them identify a statistical test or procedure appropriate to their circumstances. It further offers the guidance necessary to run these tests and procedures, then interpret and report their results. In this Technology Report we will overview the rationale behind StatHand, before describing the feature set of the application. We will then provide guidelines for integrating StatHand into the research methods curriculum, before concluding by outlining our road map for the ongoing development and evaluation of StatHand. PMID:26973579

  2. Introducing StatHand: A Cross-Platform Mobile Application to Support Students’ Statistical Decision Making

    PubMed Central

    Allen, Peter J.; Roberts, Lynne D.; Baughman, Frank D.; Loxton, Natalie J.; Van Rooy, Dirk; Rock, Adam J.; Finlay, James

    2016-01-01

    Although essential to professional competence in psychology, quantitative research methods are a known area of weakness for many undergraduate psychology students. Students find selecting appropriate statistical tests and procedures for different types of research questions, hypotheses and data types particularly challenging, and these skills are not often practiced in class. Decision trees (a type of graphic organizer) are known to facilitate this decision making process, but extant trees have a number of limitations. Furthermore, emerging research suggests that mobile technologies offer many possibilities for facilitating learning. It is within this context that we have developed StatHand, a free cross-platform application designed to support students’ statistical decision making. Developed with the support of the Australian Government Office for Learning and Teaching, StatHand guides users through a series of simple, annotated questions to help them identify a statistical test or procedure appropriate to their circumstances. It further offers the guidance necessary to run these tests and procedures, then interpret and report their results. In this Technology Report we will overview the rationale behind StatHand, before describing the feature set of the application. We will then provide guidelines for integrating StatHand into the research methods curriculum, before concluding by outlining our road map for the ongoing development and evaluation of StatHand. PMID:26973579

  3. Evolution of the JAK-STAT pathway.

    PubMed

    Liongue, Clifford; Ward, Alister C

    2013-01-01

    The JAK-STAT pathway represents a finely tuned orchestra capable of rapidly facilitating an exquisite symphony of responses from a complex array of extracellular signals. This review explores the evolution of the JAK-STAT pathway: the origins of the individual domains from which it is constructed, the formation of individual components from these basic building blocks, the assembly of the components into a functional pathway, and the subsequent reiteration of this basic template to fulfill a variety of roles downstream of cytokine receptors. PMID:24058787

  4. Evolution of the JAK-STAT pathway

    PubMed Central

    Liongue, Clifford; Ward, Alister C.

    2013-01-01

    The JAK-STAT pathway represents a finely tuned orchestra capable of rapidly facilitating an exquisite symphony of responses from a complex array of extracellular signals. This review explores the evolution of the JAK-STAT pathway: the origins of the individual domains from which it is constructed, the formation of individual components from these basic building blocks, the assembly of the components into a functional pathway, and the subsequent reiteration of this basic template to fulfill a variety of roles downstream of cytokine receptors. PMID:24058787

  5. Nanoscale Mineralogy and Composition of Experimental Regolith Agglutinates Produced under Asteroidal Impact Conditions

    NASA Technical Reports Server (NTRS)

    Christoffersen, Roy; Cintala, M. J.; Keller, L. P.; See, T. H.; Horz, F.

    2013-01-01

    On the Moon, the energetics of smaller impactors and the physical/chemical characteristics of the granular regolith target combine to form a key product of lunar space weathering: chemically reduced shock melts containing optically-active nanophase Fe metal grains (npFe0) [1]. In addition to forming the optically dark glassy matrix phase in lunar agglutinitic soil particles [1], these shock melts are becoming increasingly recognized for their contribution to optically active patina coatings on a wide range of exposed rock and grain surfaces in the lunar regolith [2]. In applying the lessons of lunar space weathering to asteroids, the potential similarities and differences in regolith-hosted shock melts on the Moon compared to those on asteroids has become a topic of increasing interest [3,4]. In a series of impact experiments performed at velocities applicable to the asteroid belt [5], Horz et al. [6] and See and Horz [7] have previously shown that repeated impacts into a gabbroic regolith analog target can produce melt-welded grain aggregates morphologically very similar to lunar agglutinates [6,7]. Although these agglutinate-like particles were extensively analyzed by electron microprobe and scanning electron microscopy (SEM) as part of the original study [7], a microstructural and compositional comparison of these aggregates to lunar soil agglutinates at sub-micron scales has yet to be made. To close this gap, we characterized a representative set of these aggregates using a JEOL 7600 field-emission scanning electron microscope (FE-SEM), and JEOL 2500SE field-emission scanning transmission electron microscope (FE-STEM) both optimized for energy dispersive X-ray spectroscopy (EDX) compositional spectrum imaging at respective analytical spatial resolutions of 0.5 to 1 micron, and 2 to 4 nm.

  6. Combined targeting of Stat3/NFκB/Cox-2/EP4 for effective management of pancreatic cancer

    PubMed Central

    Gong, Jingjing; Xie, Jianping; Bedolla, Roble; Rivas, Paul; Chakravarthy, Divya; Freeman, James W; Reddick, Robert; Kopetz, Scott; Peterson, Amanda; Wang, Huamin; Fischer, Susan M; Kumar, Addanki P

    2014-01-01

    Purpose Near equal rates of incidence and mortality emphasize the need for novel targeted approaches for better management of pancreatic cancer patients. Inflammatory molecules NFκB and Stat3 are overexpressed in pancreatic tumors. Inhibition of one protein allows cancer cells to survive using the other. The goal of the present study is to determine whether targeting Stat3/NFκB cross talk with a natural product Nexrutine (Nx) can inhibit inflammatory signaling in pancreatic cancer. Experimental design HPNE, HPNE-Ras, BxPC3, Capan-2, MIA PaCa-2 and AsPC-1 cells were tested for growth, apoptosis, Cox-2, NFκB and Stat3 level in response to Nx treatment. Transient expression, gel shift, ChIP was used to examine transcriptional regulation of Cox-2. Stat3 knockdown was used to decipher Stat3/NFκB cross talk. Histopathological and immunoblotting evaluation was performed on BK5-Cox2 transgenic mice treated with Nx. In vivo expression of prostaglandin receptor EP4 was analyzed in a retrospective cohort of pancreatic tumors using a TMA. Results Nx treatment inhibited growth of pancreatic cancer cells through induction of apoptosis. Reduced levels and activity of Stat3, NFκB and their cross talk led to transcriptional suppression of Cox-2 and subsequent decreased levels of PGE2 and PGF2. Stat3 knockdown studies suggest Stat3 as negative regulator of NFκB activation. Nx intervention reduced the levels of NFκB, Stat3 and fibrosis in vivo. Expression of prostaglandin receptor EP4 that is known to play a role in fibrosis was significantly elevated in human pancreatic tumors. Conclusions Dual inhibition of Stat3-NFκB by Nx may overcome problems associated with inhibition of either pathway. PMID:24520096

  7. Evolution of magma feeding system in Kumanodake agglutinate activity, Zao Volcano, northeastern Japan

    NASA Astrophysics Data System (ADS)

    Takebe, Yoshinori; Ban, Masao

    2015-10-01

    The Kumanodake agglutinate of Zao Volcano in northeastern Japan consists of pyroclastic surge layers accumulated during the early part of the newest stage of activity (ca. 33 ka to present). Our petrologic study of this agglutinate based on systematically collected samples aims to reveal the evolution of magma feeding system. To understand the magma evolution, we have examined samples from the agglutinate by using petrologic data including, petrography, analysis of minerals (plagioclase, pyroxene, and olivine), glass compositions, and whole rock major element and trace element (Ba, Sr, Cr, Ni, V, Rb, Zr, Nb, and Y) compositions. Agglutinate are mixed, medium-K, calc-alkaline olv-cpx-opx basaltic andesite (55.2-56.2% SiO2). Results show that the magma feeding system comprised a shallow felsic chamber injected by mafic magma from depth. The felsic magma (59-62% SiO2, 950-990 °C), which was stored at a shallower depth, had orthopyroxene (Mg# = 60-69), clinopyroxene (Mg# = 65-71), and low-An plagioclase (Anca. 58-70). The mafic magma is further divisible into two types: less-differentiated and more-differentiated, designed respectively as an initial mafic magma-1 and a second mafic magma-2. The original mafic magma-1 was olivine (Fo~ 84) basalt (ca. 48-51% SiO2, 1110-1140 °C). The second mafic magma-2, stored occasionally at 4-6 km depth, was basalt (1070-1110 °C) having Foca. 80 olivine and high-An (Anca. 90) plagioclase phenocrysts. These two magmas mixed (first mixing) to form hybrid mafic magma. The forced injections of the hybrid mafic magmas activated the felsic magma, and these two were mixed (second mixing) shortly before eruptions. The explosivity is inferred to have increased over time because the abundance of large scoria increased. Furthermore, the erupted magma composition became more mafic, which reflects increased percentage of the hybrid mafic magma involved in the second mixing. At the beginning of activity, the mafic magma also acted as a heat

  8. Serogroup identification of Neisseria meningitidis: comparison of an antiserum agar method with bacterial slide agglutination.

    PubMed Central

    Craven, D E; Frasch, C E; Robbins, J B; Feldman, H A

    1978-01-01

    A serum agar method for serogrouping Neisseria meningitidis is described and compared with conventional bacterial slide agglutination. There was 93% agreement for 300 strains examined individually by each method. Among strains from serogroups A, B, C, Y, and W135, there was 100% correlation, whereas strains from serogroup 29E (Z') had only 67% correlation. The serum agar method was rapid, as well as easy to perform and interpret. The potential benefits of this method for epidemiological studies and reference laboratories processing large numbers of meningococcal isolates are emphasized. Images PMID:96123

  9. High influx of carbon in walls of agglutinated foraminifers during the Permian-Triassic transition in global oceans

    USGS Publications Warehouse

    Nestell, Galina P.; Nestell, Merlynd K.; Ellwood, Brooks B.; Wardlaw, Bruce R.; Basu, Asish R.; Ghosh, Nilotpal; Phuong Lan, Luu Thi; Rowe, Harry D.; Hunt, Andrew G.; Tomkin, Jonathan H.; Ratcliffe, Kenneth T.

    2015-01-01

    The Permian–Triassic mass extinction is postulated to be related to the rapid volcanism that produced the Siberian flood basalt (Traps). Unrelated volcanic eruptions producing several episodes of ash falls synchronous with the Siberian Traps are found in South China and Australia. Such regional eruptions could have caused wildfires, burning of coal deposits, and the dispersion of coal fly ash. These eruptions introduced a major influx of carbon into the atmosphere and oceans that can be recognized in the wallstructure of foraminiferal tests present in survival populations in the boundary interval strata. Analysis of free specimens of foraminifers recovered from residues of conodont samples taken at aPermian–Triassic boundary section at Lung Cam in northern Vietnam has revealed the presence of a significant amount of elemental carbon, along with oxygen and silica, in their test wall structure, but an absence of calcium carbonate. These foraminifers, identified as Rectocornuspira kalhori, Cornuspira mahajeri, and Earlandia spp. and whose tests previously were considered to be calcareous, are confirmed to be agglutinated, and are now referred to as Ammodiscus kalhori and Hyperammina deformis. Measurement of the 207Pb/204Pb ratios in pyrite clusters attached to the foraminiferal tests confirmed that these tests inherited the Pb in their outer layer from carbon-contaminated seawater. We conclude that the source of the carbon could have been either global coal fly ash or forest fire-dispersed carbon, or a combination of both, that was dispersed into the Palaeo-Tethys Ocean immediately after the end-Permian extinction event.

  10. Legionella species and serogroups in Malaysian water cooling towers: identification by latex agglutination and PCR-DNA sequencing of isolates.

    PubMed

    Yong, Stacey Foong Yee; Goh, Fen-Ning; Ngeow, Yun Fong

    2010-03-01

    In this study, we investigated the distribution of Legionella species in water cooling towers located in different parts of Malaysia to obtain information that may inform public health policies for the prevention of legionellosis. A total of 20 water samples were collected from 11 cooling towers located in three different states in east, west and south Malaysia. The samples were concentrated by filtration and treated with an acid buffer before plating on to BCYE agar. Legionella viable counts in these samples ranged from 100 to 2,000 CFU ml(-1); 28 isolates from the 24 samples were examined by latex agglutination as well as 16S rRNA and rpoB PCR-DNA sequencing. These isolates were identified as Legionella pneumophila serogroup 1 (35.7%), L. pneumophila serogroup 2-14 (39%), L. pneumophila non-groupable (10.7%), L. busanensis, L. gormanii, L. anisa and L. gresilensis. L. pneumophila was clearly the predominant species at all sampling sites. Repeat sampling from the same cooling tower and testing different colonies from the same water sample showed concurrent colonization by different serogroups and different species of Legionella in some of the cooling towers. PMID:20009251

  11. STAT1:DNA sequence-dependent binding modulation by phosphorylation, protein:protein interactions and small-molecule inhibition

    PubMed Central

    Bonham, Andrew J.; Wenta, Nikola; Osslund, Leah M.; Prussin, Aaron J.; Vinkemeier, Uwe; Reich, Norbert O.

    2013-01-01

    The DNA-binding specificity and affinity of the dimeric human transcription factor (TF) STAT1, were assessed by total internal reflectance fluorescence protein-binding microarrays (TIRF-PBM) to evaluate the effects of protein phosphorylation, higher-order polymerization and small-molecule inhibition. Active, phosphorylated STAT1 showed binding preferences consistent with prior characterization, whereas unphosphorylated STAT1 showed a weak-binding preference for one-half of the GAS consensus site, consistent with recent models of STAT1 structure and function in response to phosphorylation. This altered-binding preference was further tested by use of the inhibitor LLL3, which we show to disrupt STAT1 binding in a sequence-dependent fashion. To determine if this sequence-dependence is specific to STAT1 and not a general feature of human TF biology, the TF Myc/Max was analysed and tested with the inhibitor Mycro3. Myc/Max inhibition by Mycro3 is sequence independent, suggesting that the sequence-dependent inhibition of STAT1 may be specific to this system and a useful target for future inhibitor design. PMID:23180800

  12. Antimicrobial Action and Cell Agglutination by the Eosinophil Cationic Protein Are Modulated by the Cell Wall Lipopolysaccharide Structure

    PubMed Central

    Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M. Victòria

    2012-01-01

    Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination. PMID:22330910

  13. Dataset of STAT5A status in breast cancer

    PubMed Central

    Mukhopadhyay, Utpal K.; Cass, Jamaica; Raptis, Leda; Craig, Andrew W.; Bourdeau, Véronique; Varma, Sonal; Gupta, Sandip Sen; Elliott, Bruce E.; Ferbeyre, Gerardo

    2016-01-01

    We analysed STAT5A gene expression in breast cancer using the Oncomine database. We exemplify four representative studies showing that STAT5A is generally downregulated in breast cancer. PMID:27014737

  14. Mitochondrial Stat3, the Need for Design Thinking

    PubMed Central

    Yang, Rui; Rincon, Mercedes

    2016-01-01

    Stat3 has been studied extensively as a transcription factor, however the finding that Stat3 also localizes to mitochondria has opened a new area to discover non-classical functions. Here we review the current knowledge of mitochondrial Stat3 as a regulator of the electron transport chain (ETC) and its impact on mitochondrial production of ATP and ROS. We also describe recent findings identifying Stat3 as a regulator of mitochondrial Ca2+ homeostasis through its effect on the ETC. It is becoming evident that these non-classical functions of Stat3 can have a major impact on cancer progression, cardiovascular diseases, and inflammatory diseases. Therefore, mitochondrial Stat3 functions challenge the current design of therapies that solely target Stat3 as a transcription factor and suggest the need for “design thinking,” which leads to the development of novel strategies, to intervene the Stat3 pathway. PMID:27019635

  15. Exploring dual inhibitors for STAT1 and STAT5 receptors utilizing virtual screening and dynamics simulation validation.

    PubMed

    Raj, Utkarsh; Kumar, Himansu; Gupta, Saurabh; Varadwaj, Pritish Kumar

    2016-10-01

    Signal transducer and activator of transcription (STAT) proteins are latent cytoplasmic transcription factors that transduce signals from cytokines and growth factors to the nucleus and thereby regulate the expression of a variety of target genes. Although mutations of STATs have not been reported in human tumors but the activity of several members of the family, such as STAT1 and STAT5, is deregulated in a variety of human carcinoma. STAT1 and STAT5 share a structural similarity with a highly conserved SH2 domain which is responsible for the activation of STAT proteins on interaction with phosphotyrosine motifs for specific STAT-receptor contacts and STAT dimerization. The purpose of this study is to identify domain-specific dual inhibitors for both STAT1 and STAT5 proteins from a database of natural products and natural product-like compounds comprising of over 90,000 compounds. Virtual screening-based molecular docking was performed in order to find novel natural dual inhibitors. Further, the study was supported by the 50-ns molecular dynamics simulation for receptor-ligand complexes (STAT1-STOCK-1N-69677 and STAT5-STOCK-1N-69677). Analysis of molecular interactions in the SH2 domains of both STAT1 and STAT5 proteins with the ligand revealed few conserved amino acid residues which are responsible to stabilize the ligands within the binding pocket through bonded and non-bonded interactions. This study suggested that compound STOCK-1N-69677 might putatively act as a dual inhibitor of STAT1 and STAT5 receptors, through its binding to the SH2 domain. PMID:26471877

  16. STAT2 Mediates Innate Immunity to Dengue Virus in the Absence of STAT1 via the Type I Interferon Receptor

    PubMed Central

    Perry, Stuart T.; Buck, Michael D.; Lada, Steven M.; Schindler, Christian; Shresta, Sujan

    2011-01-01

    Dengue virus (DENV) is a mosquito-borne flavivirus, and symptoms of infection range from asymptomatic to the severe dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). High viral loads correlate with disease severity, and both type I & II interferons (IFNs) are crucial for controlling viral replication. We have previously reported that signal transducer and activator of transcription (STAT) 1-deficient mice are resistant to DENV-induced disease, but little is known about this STAT1-independent mechanism of protection. To determine the molecular basis of the STAT1-independent pathway, mice lacking STAT1, STAT2, or both STAT1 and STAT2 were infected with a virulent mouse-adapted strain of DENV2. In the first 72 hours of infection, the single-deficient mice lacking STAT1 or STAT2 possessed 50–100 fold higher levels of viral RNA than wild type mice in the serum, spleen, and other visceral tissues, but remained resistant to DENV-induced death. In contrast, the double-deficient mice exhibited the early death phenotype previously observed in type I and II IFN receptor knockout mice (AG129), indicating that STAT2 is the mediator of the STAT1-independent host defense mechanism. Further studies demonstrated that this STAT2-dependent STAT1-independent mechanism requires the type I IFN receptor, and contributes to the autocrine amplification of type I IFN expression. Examination of gene expression in the spleen and bone marrow-derived macrophages following DENV infection revealed STAT2-dependent pathways can induce the transcription of a subset of interferon stimulated genes even in the absence of STAT1. Collectively, these results help elucidate the nature of the poorly understood STAT1-independent host defense mechanism against viruses by identifying a functional type I IFN/STAT2 signaling pathway following DENV infection in vivo. PMID:21379341

  17. STAT1 deficiency redirects IFN signalling toward suppression of TLR response through a feedback activation of STAT3

    PubMed Central

    Kim, Hun Sik; Kim, Dong Chan; Kim, Hong-Mi; Kwon, Hyung-Joon; Kwon, Soon Jae; Kang, Suk-Jo; Kim, Sun Chang; Choi, Go-Eun

    2015-01-01

    Interferons (IFNs) potentiate macrophage activation typically via a STAT1-dependent pathway. Recent studies suggest a functioning of STAT1-independent pathway in the regulation of gene expression by IFN-γ, thus pointing to the diversity in cellular responses to IFNs. Many functions of IFNs rely on cross-regulation of the responses to exogenous inflammatory mediators such as TLR ligands. Here we investigated the contribution of STAT1-independent pathway to macrophage activation and its underlying mechanism in the context of combined stimulation of IFN and TLR. We found that TLR-induced production of inflammatory cytokines (TNF-α, IL-12) was not simply nullified but was significantly suppressed by signaling common to IFN-γ and IFN-β in STAT1-null macrophages. Such a shift in the suppression of TLR response correlated with a sustained STAT3 activation and attenuation of NF-κB signaling. Using a JAK2/STAT3 pathway inhibitor or STAT3-specific siRNA, blocking STAT3 in that context restored TNF-α production and NF-κB signaling, thus indicating a functional cross-regulation among STAT1, STAT3, and NF-κB. Our results suggest that STAT1 deficiency reprograms IFN signaling from priming toward suppression of TLR response via feedback regulation of STAT3, which may provide a new insight into the host defense response against microbial pathogens in a situation of STAT1 deficiency. PMID:26299368

  18. Structure-Based Screen Identifies a Potent Small Molecule Inhibitor of Stat5a/b with Therapeutic Potential for Prostate Cancer and Chronic Myeloid Leukemia.

    PubMed

    Liao, Zhiyong; Gu, Lei; Vergalli, Jenny; Mariani, Samanta A; De Dominici, Marco; Lokareddy, Ravi K; Dagvadorj, Ayush; Purushottamachar, Puranik; McCue, Peter A; Trabulsi, Edouard; Lallas, Costas D; Gupta, Shilpa; Ellsworth, Elyse; Blackmon, Shauna; Ertel, Adam; Fortina, Paolo; Leiby, Benjamin; Xia, Guanjun; Rui, Hallgeir; Hoang, David T; Gomella, Leonard G; Cingolani, Gino; Njar, Vincent; Pattabiraman, Nagarajan; Calabretta, Bruno; Nevalainen, Marja T

    2015-08-01

    Bypassing tyrosine kinases responsible for Stat5a/b phosphorylation would be advantageous for therapy development for Stat5a/b-regulated cancers. Here, we sought to identify small molecule inhibitors of Stat5a/b for lead optimization and therapy development for prostate cancer and Bcr-Abl-driven leukemias. In silico screening of chemical structure databases combined with medicinal chemistry was used for identification of a panel of small molecule inhibitors to block SH2 domain-mediated docking of Stat5a/b to the receptor-kinase complex and subsequent phosphorylation and dimerization. We tested the efficacy of the lead compound IST5-002 in experimental models and patient samples of two known Stat5a/b-driven cancers, prostate cancer and chronic myeloid leukemia (CML). The lead compound inhibitor of Stat5-002 (IST5-002) prevented both Jak2 and Bcr-Abl-mediated phosphorylation and dimerization of Stat5a/b, and selectively inhibited transcriptional activity of Stat5a (IC50 = 1.5μmol/L) and Stat5b (IC50 = 3.5 μmol/L). IST5-002 suppressed nuclear translocation of Stat5a/b, binding to DNA and Stat5a/b target gene expression. IST5-002 induced extensive apoptosis of prostate cancer cells, impaired growth of prostate cancer xenograft tumors, and induced cell death in patient-derived prostate cancers when tested ex vivo in explant organ cultures. Importantly, IST5-002 induced robust apoptotic death not only of imatinib-sensitive but also of imatinib-resistant CML cell lines and primary CML cells from patients. IST5-002 provides a lead structure for further chemical modifications for clinical development for Stat5a/b-driven solid tumors and hematologic malignancies. PMID:26026053

  19. Curcumin: A Novel Stat 3 Pathway Inhibitor for Chemoprevention of Lung Cancer

    PubMed Central

    Alexandrow, Mark G.; Song, Lanxi J.; Altiok, Soner; Gray, Jhanelle; Haura, Eric B.; Kumar, Nagi B.

    2011-01-01

    Objective Multiple studies from independent groups find evidence for Stat3 activation in nearly 50% of lung cancers suggesting a functional role for this target in subsets of lung cancer. Based on the existing evidence we hypothesized that bioavailable curcuminoid complex may modulate lung carcinogenesis, primarily by inhibiting Stat3 activation. With the safety of this botanical well established, the objective of these studies is to test our hypothesis in vitro and in vivo in an effort to inform the design of a phase II chemoprevention trial in former smokers. Methods We treated non-tumor derived, normal (but immortalized) human bronchial epithelial cells (AALE) and lung adenocarcinoma derived cells (H441) with bioactive Curcumin C3 Complex. Asynchronous cells in each case were treated with curcumin for 24 hrs, followed by immunoblotting for Stat3 and activated Stat3-P, prior signal of which was used for normalization. We also completed a preclinical trial in which 12 mice were randomly divided into three groups and subjected to 3 days or 9 days of curcumin i.p. injections, followed by analysis of lung tissues for Stat3-P changes and growth suppressive effects of the curcumin. The growth suppressive effects were measured using Cyclin D1 and the replicative helicase subunit, Mcm2, as surrogates for the proliferative capacity of the tissues. Results in vitro studies with curcuminoid complex demonstrated that the activity of Stat3 in both normal bronchoepithelial cells and lung cancer derived cells is sensitive to curcumin exposure. In a dose-dependent manner, curcumin treatment resulted in significant suppression of Stat3 phosphorylation and reduction in the proliferative capacity of both cell types. In the preclinical trial with rodent models, curcumin reduced Stat3-P and the proliferative markers CycD1 and Mcm2 in mice lung tissues in vivo. Conclusion These culture and preclinical studies indicate that the activity of the Stat3 pathway can be suppressed by

  20. CANCER CONTROL AND POPULATION SCIENCES FAST STATS

    EPA Science Inventory

    Fast Stats links to tables, charts, and graphs of cancer statistics for all major cancer sites by age, sex, race, and geographic area. The statistics include incidence, mortality, prevalence, and the probability of developing or dying from cancer. A large set of statistics is ava...

  1. FastStats: Older Persons' Health

    MedlinePlus

    ... 2015, table 20 [PDF - 9.8 MB] More data Adult Day Services Centers AgingStats.gov Deaths From Unintentional Injury Among Adults Aged 65 and Over: United States, 2000–2013 Health Characteristics ... 2007 Medicare Data [PDF - 177 KB] Health, United States, trend tables ...

  2. Solar Technical Assistance Team (STAT) (Fact Sheet)

    SciTech Connect

    Not Available

    2014-05-01

    The Solar Technical Assistance Team (STAT) is a team of solar technology and deployment experts who ensure that the best information on policies, regulations, financing, and other issues is getting into the hands of state government decision makers when they need it.

  3. Understanding STAT3 signaling in cardiac ischemia.

    PubMed

    O'Sullivan, K E; Breen, E P; Gallagher, H C; Buggy, D J; Hurley, J P

    2016-05-01

    Cardiovascular disease is the leading cause of death worldwide. It remains one of the greatest challenges to global health and will continue to dominate mortality trends in the future. Acute myocardial infarction results in 7.4 million deaths globally per annum. Current management strategies are centered on restoration of coronary blood flow via percutaneous coronary intervention, coronary artery bypass grafting and administration of anti-platelet agents. Such myocardial reperfusion accounts for 40-50 % of the final infarct size in most cases. Signaling transducer and activator of transcription 3 (STAT3) has been shown to have cardioprotective effects via canonical and non-canonical activation and modulation of mitochondrial and transcriptional responses. A significant body of in vitro and in vivo evidence suggests that activation of the STAT3 signal transduction pathway results in a cardio protective response to ischemia and attempts have been made to modulate this with therapeutic effect. Not only is STAT3 important for cardiomyocyte function, but it also modulates the cardiac microenvironment and communicates with cardiac fibroblasts. To this end, we here review the current evidence supporting the manipulation of STAT3 for therapeutic benefit in cardiac ischemia and identify areas for future research. PMID:27017613

  4. FastStats: Women's Health

    MedlinePlus

    ... Care Nursing Home Care Residential Care Communities Screenings Mammography Pap Tests Disability and Risk Factors Alcohol Use ... Survey of Family Growth (from A to Z) Mammography/Breast Cancer National Ambulatory Medical Care Survey: 2012 ...

  5. A Possible Role for Agglutinated Foraminifers in the Growth of Deep-Water Coral Bioherms

    NASA Astrophysics Data System (ADS)

    Messing, C. G.; Reed, J. K.; Brooke, S. D.

    2008-05-01

    Exploration of deep-water bioherms dominated by the scleractinian corals Lophelia pertusa and Enallopsammia profunda along the east coast of Florida in ~400-800 m depth reveals an often dense and rich assemblage of small (~1-30 mm) epifauna on dead coral branches, which is often dominated by agglutinated astrorhizacean foraminifers accompanied by thecate and athecate hydroids, sponges, stylasterids, anemones and barnacles. The dominant agglutinated foraminifer is an arborescent form up to 15 mm tall, consisting of a basal tube that gives rise to branchlets of successively decreasing diameter and thickly coated with fine-grained material including coccoliths and diatom frustules. The large numbers of foraminifers generate an enormous adhesive, sediment-trapping surface area and may represent an important accelerated route for sediment deposition and bioherm growth relative to baffling of suspended sediment particles by the coral branches themselves. These foraminifers also occur on still living coral, suggesting that they may either contribute to coral death or invade stressed colonies. They may thus be responsible for or contribute to the small percent of living corals observed in many of these habitats. Other epifauna appear to colonize after the coral has died.

  6. Homogeneous agglutination assay based on micro-chip sheathless flow cytometry.

    PubMed

    Ma, Zengshuai; Zhang, Pan; Cheng, Yinuo; Xie, Shuai; Zhang, Shuai; Ye, Xiongying

    2015-11-01

    Homogeneous assays possess important advantages that no washing or physical separation is required, contributing to robust protocols and easy implementation which ensures potential point-of-care applications. Optimizing the detection strategy to reduce the number of reagents used and simplify the detection device is desirable. A method of homogeneous bead-agglutination assay based on micro-chip sheathless flow cytometry has been developed. The detection processes include mixing the capture-probe conjugated beads with an analyte containing sample, followed by flowing the reaction mixtures through the micro-chip sheathless flow cytometric device. The analyte concentrations were detected by counting the proportion of monomers in the reaction mixtures. Streptavidin-coated magnetic beads and biotinylated bovine serum albumin (bBSA) were used as a model system to verify the method, and detection limits of 0.15 pM and 1.5 pM for bBSA were achieved, using commercial Calibur and the developed micro-chip sheathless flow cytometric device, respectively. The setup of the micro-chip sheathless flow cytometric device is significantly simple; meanwhile, the system maintains relatively high sensitivity, which mainly benefits from the application of forward scattering to distinguish aggregates from monomers. The micro-chip sheathless flow cytometric device for bead agglutination detection provides us with a promising method for versatile immunoassays on microfluidic platforms. PMID:26649133

  7. An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of Apollo 11 and 16 soils

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

    1986-01-01

    Mixtures of chemically contrasting lunar soils have been shocked at pressures ranging from 18.2-62.0 GPa. Other than the generation of impact melts, modal and textural changes caused by shock include destruction of pore space and fused soil clasts and conversion of plagioclase to maskelynite. The loss of the fused soil component in these runs indicates that low agglutinate contents in shocked and/or compacted regolith breccias cannot be considered by themselves to be evidence of formation from immature regolith. From the petrographic and chemical data it appears that the impact glass formed mainly from the fine fraction and the fused soil component in the target, with relatively minor contributions from the other coarse clasts. The impact glasses exhibit the same chemical enrichments and depletions as their corresponding fine fractions and plot on or near a mixing line between the bulk and fine fraction of the soil in which they were formed. From this as well as several other studies it appears that the fusion of the finest fraction model is valid and that it accurately predicts the chemical systematics of impact glass formed from lunar soil. In addition, fusion of agglutinates present in the target soil is an important process.

  8. Biochemical Characterization and Agglutinating Properties of Xenorhabdus nematophilus F1 Fimbriae

    PubMed Central

    Moureaux, N.; Karjalainen, T.; Givaudan, A.; Bourlioux, P.; Boemare, N.

    1995-01-01

    Xenorhabdus spp., entomopathogenic bacteria symbiotically associated with nematodes of the family Steinernematidae, occur spontaneously in two phases. Only the phase I variants of Xenorhabdus nematophilus F1 expressed fimbriae when the bacteria were grown on a solid medium (nutrient agar; 24 and 48 h of growth). These appendages were purified and characterized. They were rigid, with a diameter of 6.4 (plusmn) 0.3 nm, and were composed of 16-kDa pilin subunits. The latter were synthesized and assembled during the first 24 h of growth. Phase II variants of X. nematophilus did not possess fimbriae and apparently did not synthesize pilin. Phase I variants of X. nematophilus have an agglutinating activity with sheep, rabbit, and human erythrocytes and with hemocytes of the insect Galleria mellonella. The purified fimbriae agglutinated sheep and rabbit erythrocytes. The hemagglutination by bacteria and purified fimbriae was mannose resistant and was inhibited by porcine gastric mucin and N-acetyl-lactosamine. The last sugar seems to be a specific inhibitor of hemagglutination by X. nematophilus. PMID:16535079

  9. Exploring New Biological Functions of Amyloids: Bacteria Cell Agglutination Mediated by Host Protein Aggregation

    PubMed Central

    Torrent, Marc; Pulido, David; Nogués, M. Victòria; Boix, Ester

    2012-01-01

    Antimicrobial proteins and peptides (AMPs) are important effectors of the innate immune system that play a vital role in the prevention of infections. Recent advances have highlighted the similarity between AMPs and amyloid proteins. Using the Eosinophil Cationic Protein as a model, we have rationalized the structure-activity relationships between amyloid aggregation and antimicrobial activity. Our results show how protein aggregation can induce bacteria agglutination and cell death. Using confocal and total internal reflection fluorescence microscopy we have tracked the formation in situ of protein amyloid-like aggregates at the bacteria surface and on membrane models. In both cases, fibrillar aggregates able to bind to amyloid diagnostic dyes were detected. Additionally, a single point mutation (Ile13 to Ala) can suppress the protein amyloid behavior, abolishing the agglutinating activity and impairing the antimicrobial action. The mutant is also defective in triggering both leakage and lipid vesicle aggregation. We conclude that ECP aggregation at the bacterial surface is essential for its cytotoxicity. Hence, we propose here a new prospective biological function for amyloid-like aggregates with potential biological relevance. PMID:23133388

  10. Chemical and Hormonal Effects on STAT5b-Dependent Sexual Dimorphism of the Liver Transcriptome.

    PubMed

    Oshida, Keiyu; Waxman, David J; Corton, J Christopher

    2016-01-01

    The growth hormone (GH)-activated transcription factor signal transducer and activator of transcription 5b (STAT5b) is a key regulator of sexually dimorphic gene expression in the liver. Suppression of hepatic STAT5b signaling is associated with lipid metabolic dysfunction leading to steatosis and liver cancer. In the companion publication, a STAT5b biomarker gene set was identified and used in a rank-based test to predict both increases and decreases in liver STAT5b activation status/function with high (≥ 97%) accuracy. Here, this computational approach was used to identify chemicals and hormones that activate (masculinize) or suppress (feminize) STAT5b function in a large, annotated mouse liver and primary hepatocyte gene expression compendium. Exposure to dihydrotestosterone and thyroid hormone caused liver masculinization, whereas glucocorticoids, fibroblast growth factor 15, and angiotensin II caused liver feminization. In mouse models of diabetes and obesity, liver feminization was consistently observed and was at least partially reversed by leptin or resveratrol exposure. Chemical-induced feminization of male mouse liver gene expression profiles was a relatively frequent phenomenon: of 156 gene expression biosets from chemically-treated male mice, 29% showed feminization of liver STAT5b function, while <1% showed masculinization. Most (93%) of the biosets that exhibited feminization of male liver were also associated with activation of one or more xenobiotic-responsive receptors, most commonly constitutive activated receptor (CAR) or peroxisome proliferator-activated receptor alpha (PPARα). Feminization was consistently associated with increased expression of peroxisome proliferator-activated receptor gamma (Pparg) but not other lipogenic transcription factors linked to steatosis. GH-activated STAT5b signaling in mouse liver is thus commonly altered by diverse chemicals, and provides a linkage between chemical exposure and dysregulated gene expression

  11. Targeted blockade of JAK/STAT3 signaling inhibits ovarian carcinoma growth

    PubMed Central

    Gritsina, Galina; Xiao, Fang; O'Brien, Shane W.; Gabbasov, Rashid; Maglaty, Marisa A.; Xu, Ren-Huan; Thapa, Roshan J.; Zhou, Yan; Nicolas, Emmanuelle; Litwin, Samuel; Balachandran, Siddharth; Sigal, Luis J.; Huszar, Dennis; Connolly, Denise C.

    2015-01-01

    Ovarian carcinoma (OC) is the fifth leading cause of death among women in the United States. Persistent activation of signal transducer and activator of transcription (STAT3) is frequently detected in OC. STAT3 is activated by Janus family kinases (JAK) via cytokine receptors, growth factor receptor and non-growth factor receptor tyrosine kinases. Activation of STAT3 mediates tumor cell proliferation, survival, motility, invasion, and angiogenesis, and recent work demonstrates that STAT3 activation suppresses anti-tumor immune responses and supports tumor-promoting inflammation. We hypothesized that therapeutic targeting of the JAK/STAT3 pathway would inhibit tumor growth by direct effects on OC cells and by inhibition of cells in the tumor microenvironment (TME). To test this, we evaluated the effects of a small molecule JAK inhibitor, AZD1480, on cell viability, apoptosis, proliferation, migration and adhesion of OC cells in vitro. We then evaluated the effects of AZD1480 on in vivo tumor growth and progression, gene expression, tumor-associated matrix metalloproteinase (MMP) activity and immune cell populations in a transgenic mouse model of OC. AZD1480-treatment inhibited STAT3 phosphorylation and DNA binding, and migration and adhesion of cultured OC cells and ovarian tumor growth rate, volume and ascites production in mice. In addition, drug treatment led to altered gene expression, decreased tumor-associated MMP activity, and fewer suppressor T cells in the peritoneal tumor microenvironment of tumor-bearing mice than control mice. Taken together, our results show pharmacological inhibition of the JAK2/STAT3 pathway leads to disruption of functions essential for ovarian tumor growth and progression and represents a promising therapeutic strategy. PMID:25646015

  12. Targeted Blockade of JAK/STAT3 Signaling Inhibits Ovarian Carcinoma Growth.

    PubMed

    Gritsina, Galina; Xiao, Fang; O'Brien, Shane W; Gabbasov, Rashid; Maglaty, Marisa A; Xu, Ren-Huan; Thapa, Roshan J; Zhou, Yan; Nicolas, Emmanuelle; Litwin, Samuel; Balachandran, Siddharth; Sigal, Luis J; Huszar, Dennis; Connolly, Denise C

    2015-04-01

    Ovarian carcinoma is the fifth leading cause of death among women in the United States. Persistent activation of STAT3 is frequently detected in ovarian carcinoma. STAT3 is activated by Janus family kinases (JAK) via cytokine receptors, growth factor receptor, and non-growth factor receptor tyrosine kinases. Activation of STAT3 mediates tumor cell proliferation, survival, motility, invasion, and angiogenesis, and recent work demonstrates that STAT3 activation suppresses antitumor immune responses and supports tumor-promoting inflammation. We hypothesized that therapeutic targeting of the JAK/STAT3 pathway would inhibit tumor growth by direct effects on ovarian carcinoma cells and by inhibition of cells in the tumor microenvironment (TME). To test this, we evaluated the effects of a small-molecule JAK inhibitor, AZD1480, on cell viability, apoptosis, proliferation, migration, and adhesion of ovarian carcinoma cells in vitro. We then evaluated the effects of AZD1480 on in vivo tumor growth and progression, gene expression, tumor-associated matrix metalloproteinase (MMP) activity, and immune cell populations in a transgenic mouse model of ovarian carcinoma. AZD1480 treatment inhibited STAT3 phosphorylation and DNA binding, and migration and adhesion of cultured ovarian carcinoma cells and ovarian tumor growth rate, volume, and ascites production in mice. In addition, drug treatment led to altered gene expression, decreased tumor-associated MMP activity, and fewer suppressor T cells in the peritoneal TME of tumor-bearing mice than control mice. Taken together, our results show pharmacologic inhibition of the JAK2/STAT3 pathway leads to disruption of functions essential for ovarian tumor growth and progression and represents a promising therapeutic strategy. PMID:25646015

  13. Afatinib Reduces STAT6 Signaling of Host ARPE-19 Cells Infected with Toxoplasma gondii

    PubMed Central

    Yang, Zhaoshou; Ahn, Hye-Jin; Park, Young-Hoon; Nam, Ho-Woo

    2016-01-01

    Specific gene expressions of host cells by spontaneous STAT6 phosphorylation are major strategy for the survival of intracellular Toxoplasma gondii against parasiticidal events through STAT1 phosphorylation by infection provoked IFN-γ. We determined the effects of small molecules of tyrosine kinase inhibitors (TKIs) on the growth of T. gondii and on the relationship with STAT1 and STAT6 phosphorylation in ARPE-19 cells. We counted the number of T. gondii RH tachyzoites per parasitophorous vacuolar membrane (PVM) after treatment with TKIs at 12-hr intervals for 72 hr. The change of STAT6 phosphorylation was assessed via western blot and immunofluorescence assay. Among the tested TKIs, Afatinib (pan ErbB/EGFR inhibitor, 5 µM) inhibited 98.0% of the growth of T. gondii, which was comparable to pyrimethamine (5 µM) at 96.9% and followed by Erlotinib (ErbB1/EGFR inhibitor, 20 µM) at 33.8% and Sunitinib (PDGFR or c-Kit inhibitor, 10 µM) at 21.3%. In the early stage of the infection (2, 4, and 8 hr after T. gondii challenge), Afatinib inhibited the phosphorylation of STAT6 in western blot and immunofluorescence assay. Both JAK1 and JAK3, the upper hierarchical kinases of cytokine signaling, were strongly phosphorylated at 2 hr and then disappeared entirely after 4 hr. Some TKIs, especially the EGFR inhibitors, might play an important role in the inhibition of intracellular replication of T. gondii through the inhibition of the direct phosphorylation of STAT6 by T. gondii. PMID:26951976

  14. Chemical and Hormonal Effects on STAT5b-Dependent Sexual Dimorphism of the Liver Transcriptome

    PubMed Central

    Oshida, Keiyu; Waxman, David J.; Corton, J. Christopher

    2016-01-01

    The growth hormone (GH)-activated transcription factor signal transducer and activator of transcription 5b (STAT5b) is a key regulator of sexually dimorphic gene expression in the liver. Suppression of hepatic STAT5b signaling is associated with lipid metabolic dysfunction leading to steatosis and liver cancer. In the companion publication, a STAT5b biomarker gene set was identified and used in a rank-based test to predict both increases and decreases in liver STAT5b activation status/function with high (≥ 97%) accuracy. Here, this computational approach was used to identify chemicals and hormones that activate (masculinize) or suppress (feminize) STAT5b function in a large, annotated mouse liver and primary hepatocyte gene expression compendium. Exposure to dihydrotestosterone and thyroid hormone caused liver masculinization, whereas glucocorticoids, fibroblast growth factor 15, and angiotensin II caused liver feminization. In mouse models of diabetes and obesity, liver feminization was consistently observed and was at least partially reversed by leptin or resveratrol exposure. Chemical-induced feminization of male mouse liver gene expression profiles was a relatively frequent phenomenon: of 156 gene expression biosets from chemically-treated male mice, 29% showed feminization of liver STAT5b function, while <1% showed masculinization. Most (93%) of the biosets that exhibited feminization of male liver were also associated with activation of one or more xenobiotic-responsive receptors, most commonly constitutive activated receptor (CAR) or peroxisome proliferator-activated receptor alpha (PPARα). Feminization was consistently associated with increased expression of peroxisome proliferator-activated receptor gamma (Pparg) but not other lipogenic transcription factors linked to steatosis. GH-activated STAT5b signaling in mouse liver is thus commonly altered by diverse chemicals, and provides a linkage between chemical exposure and dysregulated gene expression

  15. Human metapneumovirus small hydrophobic (SH) protein downregulates type I IFN pathway signaling by affecting STAT1 expression and phosphorylation.

    PubMed

    Hastings, Andrew K; Amato, Katherine R; Wen, Sherry C; Peterson, Laura S; Williams, John V

    2016-07-01

    Type I interferon (IFN) is a key mediator of antiviral immunity. Human metapneumovirus (HMPV) inhibits IFN signaling, but does not encode homologues of known IFN antagonists. We tested the hypothesis that a specific viral protein prevents type I IFN signaling by targeting signal transducer and activator of transcription-1 (STAT1). We found that human airway epithelial cells (capable of expressing IFNs) became impaired for STAT1 phosphorylation even without direct infection due to intrinsic negative feedback. HMPV-infected Vero cells (incapable of expressing IFN) displayed lower STAT1 expression and impaired STAT1 phosphorylation in response to type I IFN treatment compared to mock-infected cells. Transient overexpression of HMPV small hydrophobic (SH) protein significantly inhibited STAT1 phosphorylation and signaling, and recombinant virus lacking SH protein was unable to inhibit STAT1 phosphorylation. Our results indicate a role for the SH protein of HMPV in the downregulation of type I IFN signaling through the targeting of STAT1. PMID:27131212

  16. STAT3 and SOCS3 regulate NG2 cell proliferation and differentiation after contusive spinal cord injury.

    PubMed

    Hackett, Amber R; Lee, Do-Hun; Dawood, Abdul; Rodriguez, Mario; Funk, Lucy; Tsoulfas, Pantelis; Lee, Jae K

    2016-05-01

    NG2 cells, also known as oligodendrocyte progenitors or polydendrocytes, are a major component of the glial scar that forms after spinal cord injury. NG2 cells react to injury by proliferating around the lesion site and differentiating into oligodendrocytes and astrocytes, but the molecular mechanism is poorly understood. In this study, we tested the role of the transcription factor STAT3, and its suppressor SOCS3, in NG2 cell proliferation and differentiation after spinal cord injury. Using knockout mice in which STAT3 or SOCS3 are genetically deleted specifically in NG2 cells, we found that deletion of STAT3 led to a reduction in oligodendrogenesis, while deletion of SOCS3 led to enhanced proliferation of NG2 cells within the glial scar after spinal cord injury. Additionally, STAT3 and SOCS3 were not required for astrogliogenesis from NG2 cells after spinal cord injury. Interestingly, genetic deletion of STAT3 and SOCS3 did not have opposing effects, suggesting that SOCS3 may have targets other than the STAT3 pathway in NG2 cells after spinal cord injury. Altogether, our data show that both STAT3 and SOCS3 play important, yet unexpected, roles in NG2 cell proliferation and differentiation after spinal cord injury. PMID:26804026

  17. Clinicopathological differences between variants of the NAB2-STAT6 fusion gene in solitary fibrous tumors of the meninges and extra-central nervous system.

    PubMed

    Nakada, Satoko; Minato, Hiroshi; Nojima, Takayuki

    2016-07-01

    Investigations on the NAB2-STAT6 fusion gene in solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) have increased since its discovery in 2013. Although several SFTs reported without NAB2-STAT6 fusion gene analysis, we reviewed 546 SFTs/HPCs with NAB2-STAT6 fusion gene analysis in this study and investigated differences between the gene variants. In total, 452 cases tested positive for the NAB2-STAT6 fusion gene, with more than 40 variants being detected. The most frequent of these were NAB2 exon 6-STAT6 exon 16/17/18 and NAB2 exon 4-STAT6 exon 2/3, with the former occurring most frequently in SFTs in meninges, soft tissues, and head and neck; the latter predominated in SFTs in the pleura and lung. There was no difference between the histology of SFTs and fusion gene variants. A follow-up analysis of SFTs showed that 51 of 202 cases had a recurrence, with 18 of 53 meningeal SFTs having a local recurrence and/or metastasis within 0-19 years. In meninges and soft tissue, SFTs with the NAB2 exon 6-STAT6 exon 16/17/18 tended to recur more frequently than SFTs with the NAB2 exon 4-STAT6 exon 2/3. Clinicopathological data, including yearly follow-ups, are required for meningeal SFTs/HPCs to define the correlation of variants of NAB2-STAT6 fusion gene. PMID:27271270

  18. Therapeutic modulators of STAT signalling for human diseases

    PubMed Central

    Miklossy, Gabriella; Hilliard, Tyvette S.; Turkson, James

    2014-01-01

    The signal transducer and activator of transcription (STAT) proteins have important roles in biological processes. The abnormal activation of STAT signalling pathways is also implicated in many human diseases, including cancer, autoimmune diseases, rheumatoid arthritis, asthma and diabetes. Over a decade has passed since the first inhibitor of a STAT protein was reported and efforts to discover modulators of STAT signalling as therapeutics continue. This Review discusses the outcomes of the ongoing drug discovery research endeavours against STAT proteins, provides perspectives on new directions for accelerating the discovery of drug candidates, and highlights the noteworthy candidate therapeutics that have progressed to clinical trials. PMID:23903221

  19. Therapeutic modulators of STAT signalling for human diseases.

    PubMed

    Miklossy, Gabriella; Hilliard, Tyvette S; Turkson, James

    2013-08-01

    The signal transducer and activator of transcription (STAT) proteins have important roles in biological processes. The abnormal activation of STAT signalling pathways is also implicated in many human diseases, including cancer, autoimmune diseases, rheumatoid arthritis, asthma and diabetes. Over a decade has passed since the first inhibitor of a STAT protein was reported and efforts to discover modulators of STAT signalling as therapeutics continue. This Review discusses the outcomes of the ongoing drug discovery research endeavours against STAT proteins, provides perspectives on new directions for accelerating the discovery of drug candidates, and highlights the noteworthy candidate therapeutics that have progressed to clinical trials. PMID:23903221

  20. An autoregulatory enhancer controls mammary-specific STAT5 functions

    PubMed Central

    Metser, Gil; Shin, Ha Youn; Wang, Chaochen; Yoo, Kyung Hyun; Oh, Sumin; Villarino, Alejandro V.; O'Shea, John J.; Kang, Keunsoo; Hennighausen, Lothar

    2016-01-01

    Signal Transducers and Activators of Transcription (STATs) are principal transcription factors downstream of cytokine receptors. Although STAT5A is expressed in most tissues it remains to be understood why its premier, non-redundant functions are restricted to prolactin-induced mammary gland development and function. We report that the ubiquitously expressed Stat5a/b locus is subject to additional lineage-specific transcriptional control in mammary epithelium. Genome-wide surveys of epigenetic status and transcription factor occupancy uncovered a putative mammary-specific enhancer within the intergenic sequences separating the two Stat5 genes. This region exhibited several hallmarks of genomic enhancers, including DNaseI hypersensitivity, H3K27 acetylation and binding by GR, NFIB, ELF5 and MED1. Mammary-specific STAT5 binding was obtained at two canonical STAT5 binding motifs. CRISPR/Cas9-mediated genome editing was used to delete these sites in mice and determine their biological function. Mutant animals exhibited an 80% reduction of Stat5 levels in mammary epithelium and a concomitant reduction of STAT5-dependent gene expression. Transcriptome analysis identified a class of mammary-restricted genes that was particularly dependent on high STAT5 levels as a result of the intergenic enhancer. Taken together, the mammary-specific enhancer enables a positive feedback circuit that contributes to the remarkable abundance of STAT5 and, in turn, to the efficacy of STAT5-dependent mammary physiology. PMID:26446995

  1. Comparative evolutionary genomics of the STAT family of transcription factors

    PubMed Central

    Wang, Yaming; Levy, David E.

    2012-01-01

    The STAT signaling pathway is one of the seven common pathways that govern cell fate decisions during animal development. Comparative genomics revealed multiple incidences of stat gene duplications throughout metazoan evolutionary history. While pseudogenization is a frequent fate of duplicated genes, many of these STAT duplications evolved into novel genes through rapid sequence diversification and neofunctionalization. Additionally, the core of STAT gene regulatory networks, comprising stat1 through 4, stat5 and stat6, arose early in vertebrate evolution, probably through the two whole genome duplication events that occurred after the split of Cephalochordates but before the rise of Chondrichthyes. While another complete genome duplication event took place during the evolution of bony fish after their separation from the tetrapods about 450 million years ago (Mya), modern fish have only one set of these core stats, suggesting the rapid loss of most duplicated stat genes. The two stat5 genes in mammals likely arose from a duplication event in early Eutherian evolution, a period from about 310 Mya at the avian-mammal divergence to the separation of marsupials from other mammals about 130 Mya. These analyses indicate that whole genome duplications and gene duplications by unequal chromosomal crossing over were likely the major mechanisms underlying the evolution of STATs. PMID:24058748

  2. The Complex Role of STAT3 in Viral Infections

    PubMed Central

    Kuchipudi, Suresh V.

    2015-01-01

    Signal transducer and activators of transcription-3 (STAT3) regulates diverse biological functions including cell growth, differentiation, and apoptosis. In addition, STAT3 plays a key role in regulating host immune and inflammatory responses and in the pathogenesis of many cancers. Several studies reported differential regulation of STAT3 in a range of viral infections. Interestingly, STAT3 appears to direct seemingly contradictory responses and both pro- and antiviral roles of STAT3 have been described. This review summarized the currently known functions of STAT3 in the regulation of viral replication and pathogenesis of viral infections. Some of the key unanswered questions and the gap in our current understanding of the role of STAT3 in viral pathogenesis are discussed. PMID:26199948

  3. Nucleic acid-based approaches to STAT inhibition.

    PubMed

    Sen, Malabika; Grandis, Jennifer R

    2012-10-01

    Silencing of abnormally activated genes can be accomplished in a highly specific manner using nucleic acid based approaches. The focus of this review includes the different nucleic acid based inhibition strategies such as antisense oligodeoxynucleotides, small interfering RNA (siRNA), dominant-negative constructs, G-quartet oligonucleotides and decoy oligonucleotides, their mechanism of action and the effectiveness of these approaches to targeting the STAT (signal transducer and activator of transcription) proteins in cancer. Among the STAT proteins, especially STAT3, followed by STAT5, are the most frequently activated oncogenic STATs, which have emerged as plausible therapeutic cancer targets. Both STAT3 and STAT5 have been shown to regulate numerous oncogenic signaling pathways including proliferation, survival, angiogenesis and migration/invasion. PMID:24058785

  4. Breaking Ground for EncStat: A Statistics Anxiety Intervention Program.

    ERIC Educational Resources Information Center

    Watson, Freda S.; Lang, Thomas R.; Kromrey, Jeffrey D.

    A team of researchers at the University of South Florida is developing a multimedia program to identify and help students with statistics anxiety. This program, EncStat, includes tests that provide information about a student's level of anxiety and negative attitudes toward statistics, computer anxiety, and study skills, and it contains…

  5. A novel C-type lectin, Nattectin-like protein, with a wide range of bacterial agglutination activity in large yellow croaker Larimichthys crocea.

    PubMed

    Lv, Changhuan; Zhang, Dongling; Wang, Zhiyong

    2016-03-01

    C-type lectins (CTLs) are generally recognized as a superfamily of Ca(2+)-dependent carbohydrate-binding proteins, which serve as pattern recognition receptors (PRRs) in innate immunity of vertebrates. In this study, the molecular characterization and immune roles of a novel CTL from Larimichthys crocea (designated as LcNTC) were investigated. LcNTC is a novel protein that shared 33%-49% homology with other teleosts CTLs. The full-length cDNA of LcNTC was composed of 859 bp with a 465 bp open reading frame encoding a putative protein of 154 residues. LcNTC contained a single CRD with four conserved disulfide-bonded cysteine residues (Cys(57)-Cys(148), Cys(126)-Cys(140)) and EPN/AND motifs instead of invariant EPN/WND motifs required for carbohydrate-binding specificity and constructing Ca(2+)-binding sites. LcNTC mRNA was detected in all examined tissues with the most abundant in the gill. After challenged with poly I:C and Vibrio parahaemolyticus, the temporal expression of LcNTC was significantly up-regulated in the liver, spleen and head-kidney. LcNTC transcripts were also induced in the gill, skin, spleen and head-kidney post-infection with Cryptocaryon irritans. The recombinant LcNTC (rLcNTC) purified from Escherichia coli BL21 (DE3) exhibited strong agglutination activity against erythrocytes from human, rabbit and large yellow croaker in a Ca(2+)-dependent manner, and the agglutination could be inhibited by D-Mannose, D-Glucose, D-Fructose, α-Lactose, D-Maltose and LPS. Positive microbial agglutination activities of rLcNTC were observed against all tested bacteria in the presence of Ca(2+), including Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus and Micrococcus lysoleikticus) and Gram-negative bacteria (E. coli, V. parahaemolyticus, Vibrio alginolyticus and Aeromonas hydrophila). These findings collectively indicated that LcNTC might be involved in the innate immunity of L. crocea as a PRR. PMID:26828263

  6. A galectin from Eriocheir sinensis functions as pattern recognition receptor enhancing microbe agglutination and haemocytes encapsulation.

    PubMed

    Wang, Mengqiang; Wang, Lingling; Huang, Mengmeng; Yi, Qilin; Guo, Ying; Gai, Yunchao; Wang, Hao; Zhang, Huan; Song, Linsheng

    2016-08-01

    Galectins are a family of β-galactoside binding lectins that function as pattern recognition receptors (PRRs) in innate immune system of both vertebrates and invertebrates. The cDNA of Chinese mitten crab Eriocheir sinensis galectin (designated as EsGal) was cloned via rapid amplification of cDNA ends (RACE) technique based on expressed sequence tags (ESTs) analysis. The full-length cDNA of EsGal was 999 bp. Its open reading frame encoded a polypeptide of 218 amino acids containing a GLECT/Gal-bind_lectin domain and a proline/glycine rich low complexity region. The deduced amino acid sequence and domain organization of EsGal were highly similar to those of crustacean galectins. The mRNA transcripts of EsGal were found to be constitutively expressed in a wide range of tissues and mainly in hepatopancreas, gill and haemocytes. The mRNA expression level of EsGal increased rapidly and significantly after crabs were stimulated by different microbes. The recombinant EsGal (rEsGal) could bind various pathogen-associated molecular patterns (PAMPs), including lipopolysaccharide (LPS), peptidoglycan (PGN) and glucan (GLU), and exhibited strong activity to agglutinate Escherichia coli, Vibrio anguillarum, Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus and Pichia pastoris, and such agglutinating activity could be inhibited by both d-galactose and α-lactose. The in vitro encapsulation assay revealed that rEsGal could enhance the encapsulation of haemocytes towards agarose beads. These results collectively suggested that EsGal played crucial roles in the immune recognition and elimination of pathogens and contributed to the innate immune response against various microbes in crabs. PMID:27095174

  7. Cflec-5, a pattern recognition receptor in scallop Chlamys farreri agglutinating yeast Pichia pastoris.

    PubMed

    Zhang, Huan; Kong, Pengfei; Wang, Lingling; Zhou, Zhi; Yang, Jialong; Zhang, Ying; Qiu, Limei; Song, Linsheng

    2010-07-01

    C-type lectins are a superfamily of carbohydrate-recognition proteins which play crucial roles as pattern recognition receptors (PRRs) in the innate immunity. In this study, the full-length cDNA of a C-type lectin was cloned from scallop Chlamys farreri (designated as Cflec-5) by expression sequence tag (EST) analysis and rapid amplification of cDNA ends (RACE) approach. The full-length cDNA of Cflec-5 was of 1412 bp. The open reading frame encoded a polypeptide of 153 amino acids, including a signal sequence and a conserved carbohydrate-recognition domain with the EPN motif determining the mannose-binding specificity. The deduced amino acid sequence of Cflec-5 showed high similarity to members of C-type lectin superfamily. The quantitative real-time PCR was performed to investigate the tissue distribution of Cflec-5 mRNA and its temporal expression profiles in hemocytes post pathogen-associated molecular patterns (PAMPs) stimulation. In healthy scallops, the Cflec-5 mRNA was mainly detected in gill and mantle, and marginally in other tissues. The mRNA expression of Cflec-5 could be significantly induced by lipopolysaccharide (LPS) and glucan stimulation and reached the maximum level at 6 h and 12 h, respectively. But its expression level did not change significantly during peptidoglycan (PGN) stimulation. The function of Cflec-5 was investigated by recombination and expression of the cDNA fragment encoding its mature peptide in Escherichia coli Rosetta Gami (DE3). The recombinant Cflec-5 agglutinated Pichia pastoris in a calcium-independent way. The agglutinating activity could be inhibited by d-mannose, LPS and glucan, but not by d-galactose or PGN. These results collectively suggested that Cflec-5 was involved in the innate immune response of scallops and might contribute to nonself-recognition through its interaction with various PAMPs. PMID:20211738

  8. MOLECULAR PATHWAYS: JAK/STAT PATHWAY: MUTATIONS, INHIBITORS, AND RESISTANCE

    PubMed Central

    Quintás-Cardama, Alfonso; Verstovsek, Srdan

    2016-01-01

    Aberrant activation of the JAK/STAT pathway has been reported in a variety of disease states, including inflammatory conditions, hematologic malignancies, and solid tumors. For instance, a large proportion of patients with myeloproliferative neoplasms (MPNs) carry the acquired gain-of-function JAK2 V617F somatic mutation. This knowledge has dramatically improved our understanding of the pathogenesis of MPNs and it has facilitated the development of therapeutics capable of suppressing the constitutive activation of the JAK/STAT pathway, now recognized as a common underlying biological abnormality in MPNs. Ruxolitinib is an oral JAK1 and JAK2 inhibitor that has recently been approved for the treatment of myelofibrosis and has been tested against other hematologic malignancies. A series of agents with different specificities against different members of the JAK family of proteins is currently undergoing evaluation in clinical trials for patients with MPNs, lymphoma, and solid tumors such as breast or pancreatic cancer. Despite their significant clinical activity exhibited in myelofibrosis, some patients fail to respond or progress during JAK kinase inhibitor therapy. Recent reports have shed light into the mechanisms of resistance to JAK kinase inhibitor therapy. Several approaches hold promise to overcome such resistance. PMID:23406773

  9. Carbon nanotube/biocompatible bola-amphiphile supramolecular biohybrid materials: preparation and their application in bacterial cell agglutination.

    PubMed

    Yu, Guocan; Li, Jinying; Yu, Wei; Han, Chengyou; Mao, Zhengwei; Gao, Changyou; Huang, Feihe

    2013-11-26

    Supramolecular biohybrid materials were successfully constructed driven by non-covalent interactions between three biocompatible bolaform amphiphiles and single walled carbon nanotubes (SWNTs). The existence of galactoses in these supramolecular systems endowed the hybrid materials with interesting bio-function. By introducing the SWNTs as semi-flexible platforms, these supramolecular biohybrid materials display excellent agglutination ability for E. coli. PMID:23996208

  10. GENETIC ANALYSIS OF THE AGGA LOCUS INVOLVED IN AGGLUTINATION ND ADHERENCE OF PSEUDOMONAS PUTIDA, A BENEFICIAL FLUORESCENT PSEUDOMONAD

    EPA Science Inventory

    An isolate of Pseudomonas putida, which rapidly adheres to plant roots is agglutinated by a glycoprotein from root surfaces. gglutination is presented and adherence to the root surface is diminished by Tn5 insertion in mutant 5123. wo cosmid clones from wild type P putida and 2.7...

  11. Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A

    PubMed Central

    Chen, Alex; McKinley, Scott A.; Shi, Feng; Wang, Simi; Mucha, Peter J.; Harit, Dimple; Forest, M. Gregory; Lai, Samuel K.

    2015-01-01

    Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of “immune exclusion” based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers–a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates. PMID:26132216

  12. STAT3 regulated ARF expression suppresses prostate cancer metastasis

    PubMed Central

    Pencik, Jan; Schlederer, Michaela; Gruber, Wolfgang; Unger, Christine; Walker, Steven M.; Chalaris, Athena; Marié, Isabelle J.; Hassler, Melanie R.; Javaheri, Tahereh; Aksoy, Osman; Blayney, Jaine K.; Prutsch, Nicole; Skucha, Anna; Herac, Merima; Krämer, Oliver H.; Mazal, Peter; Grebien, Florian; Egger, Gerda; Poli, Valeria; Mikulits, Wolfgang; Eferl, Robert; Esterbauer, Harald; Kennedy, Richard; Fend, Falko; Scharpf, Marcus; Braun, Martin; Perner, Sven; Levy, David E.; Malcolm, Tim; Turner, Suzanne D.; Haitel, Andrea; Susani, Martin; Moazzami, Ali; Rose-John, Stefan; Aberger, Fritz; Merkel, Olaf; Moriggl, Richard; Culig, Zoran; Dolznig, Helmut; Kenner, Lukas

    2015-01-01

    Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19ARF as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF–Mdm2–p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14ARF expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition. PMID:26198641

  13. Anopheles gambiae Ag-STAT, a new insect member of the STAT family, is activated in response to bacterial infection.

    PubMed

    Barillas-Mury, C; Han, Y S; Seeley, D; Kafatos, F C

    1999-02-15

    A new insect member of the STAT family of transcription factors (Ag-STAT) has been cloned from the human malaria vector Anopheles gambiae. The domain involved in DNA interaction and the SH2 domain are well conserved. Ag-STAT is most similar to Drosophila D-STAT and to vertebrate STATs 5 and 6, constituting a proposed ancient class A of the STAT family. The mRNA is expressed at all developmental stages, and the protein is present in hemocytes, pericardial cells, midgut, skeletal muscle and fat body cells. There is no evidence of transcriptional activation following bacterial challenge. However, bacterial challenge results in nuclear translocation of Ag-STAT protein in fat body cells and induction of DNA-binding activity that recognizes a STAT target site. In vitro treatment with pervanadate (vanadate and H2O2) translocates Ag-STAT to the nucleus in midgut epithelial cells. This is the first evidence of direct participation of the STAT pathway in immune responses in insects. PMID:10022838

  14. JAK/STAT pathway dysregulation in tumors: A Drosophila perspective

    PubMed Central

    Amoyel, Marc; Anderson, Abigail M.; Bach, Erika A.

    2014-01-01

    Sustained activation of the JAK/STAT pathway is causal to human cancers. This pathway is less complex in Drosophila, and its dysregulation has been linked to several tumor models in this organism. Here, we discuss models of metastatic epithelial and hematopoietic tumors that are causally linked to dysregulation of JAK/STAT signaling in Drosophila. First, we focus on cancer models in imaginal discs where ectopic expression of the JAK/STAT pathway ligand Unpaired downstream of distinct tumor suppressors has emerged as an unexpected mediator of neoplastic transformation. We also discuss the collaboration between STAT and oncogenic Ras in epithelial transformation. Second, we examine hematopoietic tumors, where mutations that cause hyperactive JAK/STAT signaling are necessary and sufficient for “fly leukemia”. We highlight the important contributions that genetic screens in Drosophila have made to understanding the JAK/STAT pathway, its developmental roles, and how its function is co-opted during tumorigenesis. PMID:24685611

  15. Role of STAT3 in Cancer Metastasis and Translational Advances

    PubMed Central

    Patil, Prachi; Gude, Rajiv P.

    2013-01-01

    Signal transducer and activator of transcription 3 (STAT3) is a latent cytoplasmic transcription factor, originally discovered as a transducer of signal from cell surface receptors to the nucleus. It is activated by tyrosine phosphorylation at position 705 leading to its dimerization, nuclear translocation, DNA binding, and activation of gene transcription. Under normal physiological conditions, STAT3 activation is tightly regulated. However, compelling evidence suggests that STAT3 is constitutively activated in many cancers and plays a pivotal role in tumor growth and metastasis. It regulates cellular proliferation, invasion, migration, and angiogenesis that are critical for cancer metastasis. In this paper, we first describe the mechanism of STAT3 regulation followed by how STAT3 is involved in cancer metastasis, then we summarize the various small molecule inhibitors that inhibit STAT3 signaling. PMID:24199193

  16. Structure of the mouse Stat 3/5 locus: evolution from Drosophila to zebrafish to mouse.

    PubMed

    Miyoshi, K; Cui, Y; Riedlinger, G; Robinson, P; Lehoczky, J; Zon, L; Oka, T; Dewar, K; Hennighausen, L

    2001-01-15

    Signal transducers and activators of transcription (Stat) are transcription factors that can be activated by many cytokines. While Drosophila contains only one Stat (d-Stat), mammals contain seven, with STATs 3, 5a, and 5b being the closest functional relatives. To understand the evolutionary relationship between d-Stat and vertebrate STATs 3 and 5, we isolated, sequenced, and analyzed the zebrafish Stat3 (z-Stat3) gene and a 500-kb region spanning mouse chromosome 11, 60.5 cM containing three Stat genes (m-Stats). Within this region we identified the genes encoding m-Stats 3, 5a, and 5b, Cnp1, Hcrt/Orexin, Ptrf, GCN5, mDj11, and four new genes. The 5' ends of the m-Stat5a and m-Stat5b genes are juxtaposed to each other, and the 3' ends of the m-Stat3 and Stat5a genes face each other. While the m-Stat5a and m-Stat3 genes have one promoter each, which are active in many tissues, the m-Stat5b gene acquired two distinct promoters. The distal promoter is expressed ubiquitously, and transcription from the proximal promoter is restricted to liver, muscle, and mammary tissue. Through a comparison of exon-intron boundaries from the m-Stat3, m-Stat5a, and m-Stat5b, z-Stat3, and d-Stat genes, we deduced their evolutionary relationship. We propose that the Stat3 and Stat5 lineages are derived from the duplication of a common primordial gene and that d-Stat is a part of the Stat5 lineage. PMID:11161808

  17. JAK kinase inhibition abrogates STAT3 activation and head and neck squamous cell carcinoma tumor growth.

    PubMed

    Sen, Malabika; Pollock, Netanya I; Black, John; DeGrave, Kara A; Wheeler, Sarah; Freilino, Maria L; Joyce, Sonali; Lui, Vivian W Y; Zeng, Yan; Chiosea, Simion I; Grandis, Jennifer R

    2015-03-01

    Aberrant activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) 3 has been implicated in cell proliferation and survival of many cancers including head and neck squamous cell carcinoma (HNSCC). AZD1480, an orally active pharmacologic inhibitor of JAK1/JAK2, has been tested in several cancer models. In the present study, the in vitro and in vivo effects of AZD1480 were evaluated in HNSCC preclinical models to test the potential use of JAK kinase inhibition for HNSCC therapy. AZD1480 treatment decreased HNSCC proliferation in HNSCC cell lines with half maximal effective concentration (EC50) values ranging from 0.9 to 4 μM in conjunction with reduction of pSTAT3(Tyr705) expression. In vivo antitumor efficacy of AZD1480 was demonstrated in patient-derived xenograft (PDX) models derived from two independent HNSCC tumors. Oral administration of AZD1480 reduced tumor growth in conjunction with decreased pSTAT3(Tyr705) expression that was observed in both PDX models. These findings suggest that the JAK1/2 inhibitors abrogate STAT3 signaling and may be effective in HNSCC treatment approaches. PMID:25810010

  18. Procaine Attenuates Pain Behaviors of Neuropathic Pain Model Rats Possibly via Inhibiting JAK2/STAT3

    PubMed Central

    Li, Donghua; Yan, Yurong; Yu, Lingzhi; Duan, Yong

    2016-01-01

    Neuropathic pain (NPP) is the main culprit among chronic pains affecting the normal life of patients. Procaine is a frequently-used local anesthesia with multiple efficacies in various diseases. However, its role in modulating NPP has not been reported yet. This study aims at uncovering the role of procaine in NPP. Rats were pretreated with procaine by intrathecal injection. Then NPP rat model was induced by sciatic nerve chronic compression injury (CCI) and behavior tests were performed to analyze the pain behaviors upon mechanical, thermal and cold stimulations. Spinal expression of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) was detected by qRT-PCR and western blot. JAK2 was also overexpressed in procaine treated model rats for behavior tests. Results showed that procaine pretreatment improved the pain behaviors of model rats upon mechanical, thermal and cold stimulations, with the best effect occurring on the 15th day post model construction (p<0.05). Procaine also inhibited JAK2 and STAT3 expression in both mRNA (p<0.05) and protein levels. Overexpression of JAK2 increased STAT3 level and reversed the improvement effects of procaine in pain behaviors (p<0.01). These findings indicate that procaine is capable of attenuating NPP, suggesting procaine is a potential therapeutic strategy for treating NPP. Its role may be associated with the inhibition on JAK2/STAT3 signaling. PMID:27530113

  19. Radiosensitization by Inhibiting STAT1 in Renal Cell Carcinoma

    SciTech Connect

    Hui Zhouguang; Tretiakova, Maria; Zhang Zhongfa; Li Yan; Wang Xiaozhen; Zhu, Julie Xiaohong; Gao Yuanhong; Mai Weiyuan; Furge, Kyle; Qian Chaonan; Amato, Robert; Butler, E. Brian

    2009-01-01

    Purpose: Renal cell carcinoma (RCC) has been historically regarded as a radioresistant malignancy, but the molecular mechanism underlying its radioresistance is not understood. This study investigated the role of signal transducer and activator of transcription 1 (STAT1), a transcription factor downstream of the interferon-signaling pathway, in radioresistant RCC. Methods and Materials: The expressions of STAT1 and STAT3 in 164 human clear cell RCC samples, 47 papillary RCC samples, and 15 normal kidney tissue samples were examined by microarray expression profiling and immunohistochemistry. Western blotting was performed to evaluate the total and phosphorylated STAT1 expression in CRL-1932 (786-O) (human clear cell RCC), SKRC-39 (human papillary RCC), CCL-116 (human fibroblast), and CRL-1441 (G-401) (human Wilms tumor). STAT1 was reduced or inhibited by fludarabine and siRNA, respectively, and the effects on radiation-induced cell death were investigated using clonogenic assays. Results: STAT1 expression, but not STAT3 expression, was significantly greater in human RCC samples (p = 1.5 x 10{sup -8} for clear cell; and p = 3.6 x 10{sup -4} for papillary). Similarly, the expression of STAT1 was relatively greater in the two RCC cell lines. STAT1 expression was reduced by both fludarabine and siRNA, significantly increasing the radiosensitivity in both RCC cell lines. Conclusion: This is the first study reporting the overexpression of STAT1 in human clear cell and papillary RCC tissues. Radiosensitization in RCC cell lines was observed by a reduction or inhibition of STAT1 signaling, using fludarabine or siRNA. Our data suggest that STAT1 may play a key role in RCC radioresistance and manipulation of this pathway may enhance the efficacy of radiotherapy.

  20. Structural Tailoring of Advanced Turboprops (STAT) programmer's manual

    NASA Technical Reports Server (NTRS)

    Brown, K. W.; Harvey, P. R.

    1989-01-01

    The Structural Tailoring of Advanced Turboprops (STAT) computer program was developed to perform numerical optimizations on highly swept propfan blades. This manual describes the functionality of the STAT system from a programmer's viewpoint. It provides a top-down description of module intent and interaction. The purpose of this manual is to familiarize the programmer with the STAT system should he/she wish to enhance or verify the program's function.

  1. STAT3 in Cancer—Friend or Foe?

    PubMed Central

    Zhang, Hai-Feng; Lai, Raymond

    2014-01-01

    The roles and significance of STAT3 in cancer biology have been extensively studied for more than a decade. Mounting evidence has shown that constitutive activation of STAT3 is a frequent biochemical aberrancy in cancer cells, and this abnormality directly contributes to tumorigenesis and shapes many malignant phenotypes in cancer cells. Nevertheless, results from more recent experimental and clinicopathologic studies have suggested that STAT3 also can exert tumor suppressor effects under specific conditions. Importantly, some of these studies have demonstrated that STAT3 can function either as an oncoprotein or a tumor suppressor in the same cell type, depending on the specific genetic background or presence/absence of specific coexisting biochemical defects. Thus, in the context of cancer biology, STAT3 can be a friend or foe. In the first half of this review, we will highlight the “evil” features of STAT3 by summarizing its oncogenic functions and mechanisms. The differences between the canonical and non-canonical pathway will be highlighted. In the second half, we will summarize the evidence supporting that STAT3 can function as a tumor suppressor. To explain how STAT3 may mediate its tumor suppressor effects, we will discuss several possible mechanisms, one of which is linked to the role of STAT3β, one of the two STAT3 splicing isoforms. Taken together, it is clear that the roles of STAT3 in cancer are multi-faceted and far more complicated than one appreciated previously. The new knowledge has provided us with new approaches and strategies when we evaluate STAT3 as a prognostic biomarker or therapeutic target. PMID:24995504

  2. Targeting transcription factor STAT3 for cancer prevention and therapy.

    PubMed

    Chai, Edna Zhi Pei; Shanmugam, Muthu K; Arfuso, Frank; Dharmarajan, Arunasalam; Wang, Chao; Kumar, Alan Prem; Samy, Ramar Perumal; Lim, Lina H K; Wang, Lingzhi; Goh, Boon Cher; Ahn, Kwang Seok; Hui, Kam Man; Sethi, Gautam

    2016-06-01

    Signal Transducers and Activators of Transcription (STATs) comprise an important class of transcription factors that have been implicated in a wide variety of essential cellular functions related to proliferation, survival, and angiogenesis. Among various STAT members, STAT3 is frequently overexpressed in tumor cells as well as tissue samples, and regulates the expression of numerous oncogenic genes controlling the growth and metastasis of tumor cells. The current review briefly discusses the importance of STAT3 as a potential target for cancer therapy and also provides novel insights into various classes of existing pharmacological inhibitors of this transcription factor that can be potentially developed as anti-cancer drugs. PMID:26478441

  3. Mast cell homeostasis and the JAK–STAT pathway

    PubMed Central

    Morales, JK; Falanga, YT; Depcrynski, A; Fernando, J; Ryan, JJ

    2011-01-01

    The Janus kinase/signal transducer and activator of transcription (JAK–STAT) pathway mediates important responses in immune cells. Activation of any of the four JAK family members leads to phosphorylation of one or more of seven STAT family members. Phosphorylation of STAT family members leads to their dimerization and translocation into the nucleus, in which they bind specific DNA sequences to activate gene transcription. Regulation of JAKs and STATs therefore has a significant effect on signal transduction and subsequent cellular responses. Mast cells are important mediators of allergic disease and asthma. These cells have the ability to cause profound inflammation and vasodilation upon the release of preformed mediators, as well as subsequent synthesis of new inflammatory mediators. The regulation of mast cells is therefore of intense interest for the treatment of allergic disease. An important regulator of mast cells, STAT5, is activated downstream of the receptors for immunoglobulin E, interleukin-3 and stem cell factor. STAT5 contributes to mast cell homeostasis, by mediating proliferation, survival, and mediator release. Regulators of the JAK–STAT pathway, such as the suppressors of cytokine signaling (SOCS) and protein inhibitor of activated STAT (PIAS) proteins, are required to fine tune the immune response and maintain homeostasis. A better understanding of the role and regulation of JAKs and STATs in mast cells is vital for the development of new therapeutics. PMID:20535135

  4. STAT3 Inhibitors: Finding a Home in Lymphoma and Leukemia

    PubMed Central

    Munoz, Javier; Dhillon, Navjot; Janku, Filip; Watowich, Stephanie S.

    2014-01-01

    The Janus kinase (JAK) and signal transducer and activator of transcription (STAT) pathway is an active mediator of cytokine signaling in the pathogenesis of solid and hematologic malignancies. The seven-member STAT family is composed of latent cytoplasmic transcription factors that are activated by phosphorylation intertwined in a network with activation that ultimately leads to cell proliferation. An activated kinase enzyme phosphorylates one STAT factor or more, which shuttle to the nucleus to regulate gene expression, promoting cell survival. Somatic STAT3 mutations have been recently reported in large granular lymphocytic leukemia, aplastic anemia, and myelodysplastic syndrome. Furthermore, the relationship between BCL6 and STAT3 in diffuse large B-cell lymphomas, particularly on the activated B-cell subtype, needs to be further explored. The search for therapeutic STAT3 inhibitors that abrogate the JAK/STAT pathway is currently under way. Targeting the STAT pathway, which seems to be critical in tumorigenesis, is promising for multiple malignancies including lymphoma and leukemia. In this paper, we review mechanisms of action, failures, and successes of STAT3 inhibitors. PMID:24705981

  5. The role of JAK-STAT signaling within the CNS.

    PubMed

    Nicolas, Celine S; Amici, Mascia; Bortolotto, Zuner A; Doherty, Andrew; Csaba, Zsolt; Fafouri, Assia; Dournaud, Pascal; Gressens, Pierre; Collingridge, Graham L; Peineau, Stephane

    2013-01-01

    JAK-STAT is an efficient and highly regulated system mainly dedicated to the regulation of gene expression. Primarily identified as functioning in hematopoietic cells, its role has been found critical in all cell types, including neurons. This review will focus on JAK-STAT functions in the mature central nervous system. Our recent research suggests the intriguing possibility of a non-nuclear role of STAT3 during synaptic plasticity. Dysregulation of the JAK-STAT pathway in inflammation, cancer and neurodegenerative diseases positions it at the heart of most brain disorders, highlighting the importance to understand how it can influence the fate and functions of brain cells. PMID:24058789

  6. STAT5B deficiency: Impacts on human growth and immunity.

    PubMed

    Hwa, Vivian

    2016-06-01

    Growth hormone (GH) promotes postnatal human growth primarily by regulating insulin-like growth factor (IGF)-I production through activation of the GH receptor (GHR)-signal transducer and activator of transcription (STAT)-5B signaling cascade. The critical importance of STAT5B in human IGF-I production was confirmed with the identification of the first homozygous, autosomal recessive, STAT5B mutation in a young female patient who phenotypically resembled patients with classical growth hormone insensitivity (GHI) syndrome (Laron syndrome) due to mutations in the GHR gene, presenting with severe postnatal growth failure and marked IGF-I deficiency. Of note, the closely related STAT5A, which shares >95% amino acid identity with STAT5B, could not compensate for loss of functional STAT5B. To date, 7 homozygous, inactivating, STAT5B mutations in 10 patients have been reported. STAT5B deficient patients, unlike patients deficient in GHR, can also present with a novel, potentially fatal, primary immunodeficiency, which can manifest as chronic pulmonary disease. STAT5B deficiency may be underestimated in endocrine, immunology and pulmonary clinics. PMID:26703237

  7. Interleukin 2 signaling involves the phosphorylation of Stat proteins.

    PubMed

    Frank, D A; Robertson, M J; Bonni, A; Ritz, J; Greenberg, M E

    1995-08-15

    One of the most important cytokines involved in immune response regulation is interleukin 2 (IL-2), a potent activator of the proliferation and function of T lymphocytes and natural killer cells. The mechanisms by which the effects of IL-2 are propagated within cells are not understood. While the binding of IL-2 to its receptor was recently shown to lead to the activation of two kinases, Jak-1 and Jak-3, subsequent steps in the signaling pathway to the nucleus that lead to the activation of specific genes had not been characterized. Since many cytokines that activate Jak kinases also lead to the tyrosine phosphorylation and activation of members of the Stat family of transcription factors, the ability of IL-2 to trigger Stat phosphorylation was examined. Exposure of activated human T lymphocytes or of a natural killer cell line (NKL) to IL-2 leads to the phosphorylation of Stat1 alpha, Stat1 beta, and Stat3, as well as of two Stat-related proteins, p94 and p95. p94 and p95 share homology with Stat1 at the phosphorylation site and in the Src homology 2 (SH2) domain, but otherwise are immunologically distinct from Stat1. These Stat proteins were found to translocate to the nucleus and to bind to a specific DNA sequence. These findings suggest a mechanism by which IL-2 binding to its receptor may activate specific genes involved in immune cell function. PMID:7544001

  8. Possible involvement of the JAK/STAT signaling pathway in N-acetylcysteine-mediated antidepressant-like effects.

    PubMed

    Al-Samhari, Marwa M; Al-Rasheed, Nouf M; Al-Rejaie, Salim; Al-Rasheed, Nawal M; Hasan, Iman H; Mahmoud, Ayman M; Dzimiri, Nduna

    2016-03-01

    Advances in depression research have targeted inflammation and oxidative stress to develop novel types of treatment. The JAK/STAT signaling pathway plays pivotal roles in immune and inflammatory responses. The present study was designed to investigate the effects of N-acetylcysteine, a putative precursor of the antioxidant glutathione, in an animal model of depression, with an emphasis on the JAK/STAT signaling pathway. Fluoxetine, a classical antidepressant drug was also under investigation. Male Wistar rats were subjected to forced swimming test and given N-acetylcysteine and fluoxetine immediately after the pre-test session, 5 h later and 1 h before the test session of the forced swimming test. N-acetylcysteine decreased immobility time (P < 0.05), serum corticosterone (P < 0.001), and hydrogen peroxide (P < 0.001), while restored glutathione concentration. Treatment of the rats with N-acetylcysteine produced significant (P < 0.001) down-regulation of STAT3 mRNA expression and protein phosphorylation. On the other hand, N-acetylcysteine significantly (P < 0.001) increased SOCS3 gene expression; however, SOCS3 protein was not changed. In conclusion, our study suggests that modulation of the JAK/STAT pathway might mediate the antidepressant-like effects of N-acetylcysteine. Therefore, depression research may target the JAK/STAT signaling pathway to provide a novel effective therapy. PMID:26643864

  9. A New STAT3-binding Partner, ARL3, Enhances the Phosphorylation and Nuclear Accumulation of STAT3.

    PubMed

    Togi, Sumihito; Muromoto, Ryuta; Hirashima, Koki; Kitai, Yuichi; Okayama, Taichiro; Ikeda, Osamu; Matsumoto, Naoki; Kon, Shigeyuki; Sekine, Yuichi; Oritani, Kenji; Matsuda, Tadashi

    2016-05-20

    Signal transducer and activator of transcription 3 (STAT3) is involved in cell proliferation, differentiation, and cell survival during immune responses, hematopoiesis, neurogenesis, and other biological processes. STAT3 activity is regulated by a variety of mechanisms, including phosphorylation and nuclear translocation. To clarify the molecular mechanisms underlying the regulation of STAT3 activity, we performed yeast two-hybrid screening. We identified ARL3 (ADP-ribosylation factor-like 3) as a novel STAT3-binding partner. ARL3 recognizes the DNA-binding domain as well as the C-terminal region of STAT3 in vivo, and their binding was the strongest when both proteins were activated. Importantly, small interfering RNA-mediated reduction of endogenous ARL3 expression decreased IL-6-induced tyrosine phosphorylation, nuclear accumulation, and transcriptional activity of STAT3. These results indicate that ARL3 interacts with STAT3 and regulates the transcriptional activation of STAT3 by influencing its nuclear accumulation of STAT3. PMID:27048653

  10. The non-pathogenic Henipavirus Cedar paramyxovirus phosphoprotein has a compromised ability to target STAT1 and STAT2.

    PubMed

    Lieu, Kim G; Marsh, Glenn A; Wang, Lin-Fa; Netter, Hans J

    2015-12-01

    Immune evasion by the lethal henipaviruses, Hendra (HeV) and Nipah virus, is mediated by its interferon (IFN) antagonist P gene products, phosphoprotein (P), and the related V and W proteins, which can target the signal transducer and activator of transcription 1 (STAT1) and STAT2 proteins to inhibit IFN/STAT signaling. However, it is not clear if the recently identified non-pathogenic Henipavirus, Cedar paramyxovirus (CedPV), is also able to antagonize the STAT proteins. We performed comparative studies between the HeV P gene products (P/V/W) and CedPV-P (CedPV does not encode V or W) and demonstrate that differences exist in their ability to engage the STAT proteins using immunoprecipitation and quantitative confocal microscopic analysis. In contrast to HeV-P gene encoded proteins, the ability of CedPV-P to interact with and relocalize STAT1 or STAT2 is compromised, correlating with a reduced capacity to inhibit the mRNA synthesis of IFN-inducible gene MxA. Furthermore, infection studies with HeV and CedPV demonstrate that HeV is more potent than CedPV in inhibiting the IFN-α-mediated nuclear accumulation of STAT1. These results strongly suggest that the ability of CedPV to counteract the IFN/STAT response is compromised compared to HeV. PMID:26526590

  11. Activation of Hepatic STAT3 Maintains Pulmonary Defense during Endotoxemia

    PubMed Central

    Hilliard, Kristie L.; Allen, Eri; Traber, Katrina E.; Kim, Yuri; Wasserman, Gregory A.; Jones, Matthew R.; Mizgerd, Joseph P.

    2015-01-01

    Pneumonia and infection-induced sepsis are worldwide public health concerns. Both pathologies elicit systemic inflammation and induce a robust acute-phase response (APR). Although APR activation is well regarded as a hallmark of infection, the direct contributions of liver activation to pulmonary defense during sepsis remain unclear. By targeting STAT3-dependent acute-phase changes in the liver, we evaluated the role of liver STAT3 activity in promoting host defense in the context of sepsis and pneumonia. We employed a two-hit endotoxemia/pneumonia model, whereby administration of 18 h of intraperitoneal lipopolysaccharide (LPS; 5 mg/kg of body weight) was followed by intratracheal Escherichia coli (106 CFU) in wild-type mice or those lacking hepatocyte STAT3 (hepSTAT3−/−). Pneumonia alone (without endotoxemia) was effectively controlled in the absence of liver STAT3. Following endotoxemia and pneumonia, however, hepSTAT3−/− mice, with significantly reduced levels of circulating and airspace acute-phase proteins, exhibited significantly elevated lung and blood bacterial burdens and mortality. These data suggested that STAT3-dependent liver responses are necessary to promote host defense. While neither recruited airspace neutrophils nor lung injury was altered in endotoxemic hepSTAT3−/− mice, alveolar macrophage reactive oxygen species generation was significantly decreased. Additionally, bronchoalveolar lavage fluid from this group of hepSTAT3−/− mice allowed greater bacterial growth ex vivo. These results suggest that hepatic STAT3 activation promotes both cellular and humoral lung defenses. Taken together, induction of liver STAT3-dependent gene expression programs is essential to countering the deleterious consequences of sepsis on pneumonia susceptibility. PMID:26216424

  12. Activation of Hepatic STAT3 Maintains Pulmonary Defense during Endotoxemia.

    PubMed

    Hilliard, Kristie L; Allen, Eri; Traber, Katrina E; Kim, Yuri; Wasserman, Gregory A; Jones, Matthew R; Mizgerd, Joseph P; Quinton, Lee J

    2015-10-01

    Pneumonia and infection-induced sepsis are worldwide public health concerns. Both pathologies elicit systemic inflammation and induce a robust acute-phase response (APR). Although APR activation is well regarded as a hallmark of infection, the direct contributions of liver activation to pulmonary defense during sepsis remain unclear. By targeting STAT3-dependent acute-phase changes in the liver, we evaluated the role of liver STAT3 activity in promoting host defense in the context of sepsis and pneumonia. We employed a two-hit endotoxemia/pneumonia model, whereby administration of 18 h of intraperitoneal lipopolysaccharide (LPS; 5 mg/kg of body weight) was followed by intratracheal Escherichia coli (10(6) CFU) in wild-type mice or those lacking hepatocyte STAT3 (hepSTAT3(-/-)). Pneumonia alone (without endotoxemia) was effectively controlled in the absence of liver STAT3. Following endotoxemia and pneumonia, however, hepSTAT3(-/-) mice, with significantly reduced levels of circulating and airspace acute-phase proteins, exhibited significantly elevated lung and blood bacterial burdens and mortality. These data suggested that STAT3-dependent liver responses are necessary to promote host defense. While neither recruited airspace neutrophils nor lung injury was altered in endotoxemic hepSTAT3(-/-) mice, alveolar macrophage reactive oxygen species generation was significantly decreased. Additionally, bronchoalveolar lavage fluid from this group of hepSTAT3(-/-) mice allowed greater bacterial growth ex vivo. These results suggest that hepatic STAT3 activation promotes both cellular and humoral lung defenses. Taken together, induction of liver STAT3-dependent gene expression programs is essential to countering the deleterious consequences of sepsis on pneumonia susceptibility. PMID:26216424

  13. Monitoring microbial populations of sulfate-reducing bacteria using an impedimetric immunosensor based on agglutination assay.

    PubMed

    Wan, Yi; Zhang, Dun; Hou, Baorong

    2009-11-15

    An impedimetric immunosensor was fabricated for rapid and non-labeled detection of sulfate-reducing bacteria, Desulforibrio caledoiensis (SRB) by immobilizing lectin-Concanavalin A using an agglutination assay. The immobilization of lectin was conducted using amine coupling on the surface of a gold (Au) electrode assembled with 11-Mercaptoundecanoic acid. Electrochemical impedance spectroscopy (EIS) was used to verify the stepwise assembly of the sensor system. The work conditions of the impedimetric immunosensor, such as pH of the buffer solutions and the incubation time of lectin, were optimized. Faradic impedance spectra for charge transfer for the redox probe Fe(CN)(6)(3-/4-)were measured to determine SRB concentrations. The diameter of the Nyquist diagram that is equal to the charge-transfer resistance (R(ct)) increased with increasing SRB concentration. A linear relationship between R(ct) and SRB concentration was obtained in SRB concentration range of 1.8 to 1.8 x 10(7)cfu/ml. The variation of the SRB population during the growth process was also monitored using the impedimetric immunosensor. This approach has great potential for simple, low-cost, and time-saving monitoring of microbial populations. PMID:19782217

  14. Microscopic agglutination and polyacrylamide gel electrophoresis analyses of oral anaerobic spirochetes.

    PubMed Central

    Tall, B D; Nauman, R K

    1986-01-01

    Microscopic agglutination (MA) analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to determine strain and species similarities and dissimilarities among three species of oral anaerobic spirochetes, Treponema denticola, Treponema pectinovorum, and Treponema vincentii. The MA analysis revealed a diversity of serologic reactivity or sharing of common antigens within each species. However, there was no cross-reactivity or sharing of common antigens among the three species. Distinct SDS-PAGE whole-cell electrophoretograms for each species were obtained. The banding patterns for 16 T. denticola strains revealed 30 distinct proteins, while the banding patterns for 5 strains of T. pectinovorum and 2 strains of T. vincentii revealed 26 and 35 distinct proteins, respectively. Analysis of the electrophoretograms showed that their respective banding patterns could be used to distinguish the three species from one another. In addition, strain differences within each species could be detected. There was a correlation between MA analysis and SDS-PAGE analysis. It is thus suggested that both MA and SDS-PAGE analysis be included in classification schemes for the identification of oral spirochetes. Images PMID:3745424

  15. Discovery of novel Jak2-Stat pathway inhibitors with extended residence time on target.

    PubMed

    Guan, Huiping; Lamb, Michelle L; Peng, Bo; Huang, Shan; Degrace, Nancy; Read, Jon; Hussain, Syeed; Wu, Jiaquan; Rivard, Caroline; Alimzhanov, Marat; Bebernitz, Geraldine; Bell, Kirsten; Ye, Minwei; Zinda, Michael; Ioannidis, Stephanos

    2013-05-15

    The discovery of the activating mutation V617F in the JH2 domain of Jak2 and the modulation of oncogenic Stat3 by Jak2 inhibitors have spurred a great interest in the inhibition of the Jak2/Stat pathway in oncology. In this Letter, we communicate the discovery of novel inhibitors of the Jak2/Stat5 axis, the N-(1H-pyrazol-3-yl)pyrimidin-2-amino derivatives. The rationale, synthesis and biological evaluation of these derivatives are reported. Two lead analogs from this series, 6 and 9, displayed prolonged residence time on Jak2, at enzymatic level. Although 6 and 9 exhibited moderate selectivity in a selected kinase panel, we chose to test these inhibitors in vivo as a consequence to their long residence time. However, extended inhibition of Jak2 due to the long residence time, in the form of inhibiting phosphorylation of downstream Stat5, was not recapitulated in an in vivo setting. PMID:23562594

  16. GridStat – Cyber Security and Regional Deployment Project Report

    SciTech Connect

    Clements, Samuel L.

    2009-02-18

    GridStat is a developing communication technology to provide real-time data delivery services to the electric power grid. It is being developed in a collaborative effort between the Electrical Power Engineering and Distributed Computing Science Departments at Washington State University. Improving the cyber security of GridStat was the principle focus of this project. A regional network was established to test GridStat’s cyber security mechanisms in a realistic environment. The network consists of nodes at Pacific Northwest National Laboratory, Idaho National Laboratory, and Washington State University. Idaho National Laboratory (INL) was tasked with performing the security assessment, the results of which detailed a number or easily resolvable and previously unknown issues, as well as a number of difficult and previously known issues. Going forward we recommend additional development prior to commercialization of GridStat. The development plan is structured into three domains: Core Development, Cyber Security and Pilot Projects. Each domain contains a number of phased subtasks that build upon each other to increase the robustness and maturity of GridStat.

  17. An acousto-optical method for registration of erythrocytes' agglutination reaction—sera color influence on the resolving power

    NASA Astrophysics Data System (ADS)

    Doubrovski, V. A.; Medvedeva, M. F.; Torbin, S. O.

    2016-01-01

    The absorption spectra of agglutinating sera were used to determine blood groups. It was shown experimentally that the sera color significantly affects the resolving power of the acousto-optical method of blood typing. In order to increase the resolving power of the method and produce an invariance of the method for sera color, we suggested introducing a probing light beam individually for different sera. The proposed technique not only improves the resolving power of the method, but also reduces the risk of false interpretation of the experimental results and, hence, error in determining the blood group of the sample. The latter is especially important for the typing of blood samples with weak agglutination of erythrocytes. This study can be used in the development of an instrument for instrumental human blood group typing based on the acousto-optical method.

  18. STAT1-S727 - the license to kill

    PubMed Central

    Putz, Eva M.; Gotthardt, Dagmar; Sexl, Veronika

    2014-01-01

    Serine phosphorylation has generally been considered indispensable for full transcriptional activity of STAT proteins. Recent data indicate that CDK8-mediated phosphorylation of signal transducer and activator of transcription 1 (STAT1) on S727 inhibits natural killer (NK) cell cytotoxicity and restrains tumor surveillance. These findings implicate CDK8 as a promising target for immunotherapy. PMID:25941617

  19. Agglutinating Activity and Structural Characterization of Scalarin, the Major Egg Protein of the Snail Pomacea scalaris (d’Orbigny, 1832)

    PubMed Central

    Ituarte, Santiago; Dreon, Marcos Sebastián; Ceolin, Marcelo; Heras, Horacio

    2012-01-01

    Apple snail perivitellins are emerging as ecologically important reproductive proteins. To elucidate if the protective functions of the egg proteins of Pomacea canaliculata (Caenogastropoda, Ampullariidae), involved in embryo defenses, are present in other Pomacea species we studied scalarin (PsSC), the major perivitellin of Pomacea scalaris. Using small angle X-ray scattering, fluorescence and absorption spectroscopy and biochemical methods, we analyzed PsSC structural stability, agglutinating activity, sugar specificity and protease resistance. PsSC aggluttinated rabbit, and, to a lesser extent, human B and A erythrocytes independently of divalent metals Ca2+ and Mg2+ were strongly inhibited by galactosamine and glucosamine. The protein was structurally stable between pH 2.0 to 10.0, though agglutination occurred only between pH 4.0 to 8.0 (maximum activity at pH 7.0). The agglutinating activity was conserved up to 60°C and completely lost above 80°C, in agreement with the structural thermal stability of the protein (up to 60°C). PsSC was able to withstand in vitro gastrointestinal digestion, and showed no trypsin inhibition activity. The presence of lectin activity has been reported in eggs of other Pomacea snails, but here we link for the first time, this activity to an apple snail multifunctional perivitellin. This novel role for a snail egg storage protein is different from closely related P.canaliculata defensive proteins. PMID:23185551

  20. Application of a spectrally filtered probing light beam and RGB decomposition of microphotographs for flow registration of ultrasonically enhanced agglutination of erythrocytes

    NASA Astrophysics Data System (ADS)

    Doubrovski, V. A.; Ganilova, Yu. A.; Zabenkov, I. V.

    2013-08-01

    We propose a development of the flow microscopy method to increase the resolving power upon registration of erythrocyte agglutination. We experimentally show that the action of a ultrasonic standing wave on an agglutinating mixture blood-serum leads to the formation of so large erythrocytic immune complexes that it seems possible to propose a new two-wave optical method of registration of the process of erythrocyte agglutination using the RGB decomposition of microphotographs of the flow of the mixture under study. This approach increases the reliability of registration of erythrocyte agglutination and, consequently, increases the reliability of blood typing. Our results can be used in the development of instruments for automatic human blood typing.

  1. An insight into JAK-STAT signalling in dermatology.

    PubMed

    Palanivel, J A; Macbeth, A E; Chetty, N C; Levell, N J

    2014-06-01

    Many emerging studies have implicated the Janus kinase/signal transducer and activator of transcription (JAK-STAT) cytokine signalling mechanism in disease pathogenesis. This signalling pathway is involved in haematopoiesis and immune development. Mutations in genes regulating JAK-STAT signalling can cause common inflammatory disorders and myeloproliferative disorders. JAK and STAT inhibitors are new management tools for disorders such as myelofibrosis and rheumatoid arthritis. Evidence suggests that the cytokine components of the JAK-STAT pathways play a crucial role in common skin disorders, including psoriasis and atopic dermatitis. We present an overview for the clinical dermatologist of the significance of these signalling pathways in various skin disorders, and introduce the potential application of JAK and STAT inhibition as a new therapeutic tool in dermatology. PMID:24825142

  2. Propulsion Study for Small Transport Aircraft Technology (STAT)

    NASA Technical Reports Server (NTRS)

    Gill, J. C.; Earle, R. V.; Staton, D. V.; Stolp, P. C.; Huelster, D. S.; Zolezzi, B. A.

    1980-01-01

    Propulsion requirements were determined for 0.5 and 0.7 Mach aircraft. Sensitivity studies were conducted on both these aircraft to determine parametrically the influence of propulsion characteristics on aircraft size and direct operating cost (DOC). Candidate technology elements and design features were identified and parametric studies conducted to select the STAT advanced engine cycle. Trade off studies were conducted to determine those advanced technologies and design features that would offer a reduction in DOC for operation of the STAT engines. These features were incorporated in the two STAT engines. A benefit assessment was conducted comparing the STAT engines to current technology engines of the same power and to 1985 derivatives of the current technology engines. Research and development programs were recommended as part of an overall technology development plan to ensure that full commercial development of the STAT engines could be initiated in 1988.

  3. Concurrent CD44s and STAT3 expression in human clear cell renal cellular carcinoma and its impact on survival

    PubMed Central

    Qin, Jun; Yang, Bo; Xu, Bao-Qin; Smithc, Amber; Xu, Liang; Yuan, Jian-Lin; Li, Ling

    2014-01-01

    Although CD44 was overexpressed and considered as a useful prognostic marker in renal cell carcinoma, the prognostic role of CD44s in clear cell renal cell carcinoma (ccRCC) remains controversial. Moreover, the correlation and prognostic significance of CD44s and its downstream signaling target pSTAT3 are unclear in ccRCC. In this study, 75 pairs of carcinoma and paired adjacent non-tumor renal tissue samples were collected from patients with localized ccRCC who underwent a nephrectomy. The expression levels of CD44s and pSTAT3 were analyzed using immunohistochemistry. Correlations between CD44s/pSTAT3 expression and clinical and pathological characteristics were determined using x2 test, Kaplan-Meier analysis and Cox’s proportional hazards model. We found that CD44s is highly expressed in 46.67% of tumor tissues, and its high expression was significantly associated with high tumor grade (P < 0.001), large tumor size (P = 0.009) and advanced T stage (P = 0.004). A strong correlation exists between high expression of CD44s and pSTAT3 (r = 0.4013, P = 0.0004). The joint over expression of CD44s and pSTAT3 was present in 42.66% of tumor specimens and had an additive negative impact on overall survival. Patients with CD44shighpSTAT3high expression had significantly poor survival as compared to patients with CD44slowpSTAT3low tumor expression (P = 0.024), though the concurrent overexpression of CD44s and pSTAT3 was not an independent prognostic factor for overall survival. Our data indicate that expression of both CD44s and pSTAT3 in ccRCC is associated with advanced tumor stage and patient survival. The conclusions from this study may improve the prediction of ccRCC prognosis information when CD44s and pSTAT3 expression are evaluated together with classical clinicopathological parameters. PMID:25031744

  4. STAT3 and STAT6 Signaling Pathways Synergize to Promote Cathepsin Secretion from Macrophages via IRE1α Activation.

    PubMed

    Yan, Dongyao; Wang, Hao-Wei; Bowman, Robert L; Joyce, Johanna A

    2016-09-13

    Tumor-associated macrophages play critical roles during tumor progression by promoting angiogenesis, cancer cell proliferation, invasion, and metastasis. Cysteine cathepsin proteases, produced by macrophages and cancer cells, modulate these processes, but it remains unclear how these typically lysosomal enzymes are regulated and secreted within the tumor microenvironment. Here, we identify a STAT3 and STAT6 synergy that potently upregulates cathepsin secretion by macrophages via engagement of an unfolded protein response (UPR) pathway. Whole-genome expression analyses revealed that the TH2 cytokine interleukin (IL)-4 synergizes with IL-6 or IL-10 to activate UPR via STAT6 and STAT3. Pharmacological inhibition of the UPR sensor IRE1α blocks cathepsin secretion and blunts macrophage-mediated cancer cell invasion. Similarly, genetic deletion of STAT3 and STAT6 signaling components impairs tumor development and invasion in vivo. Together, these findings demonstrate that cytokine-activated STAT3 and STAT6 cooperate in macrophages to promote a secretory phenotype that enhances tumor progression in a cathepsin-dependent manner. PMID:27626662

  5. Different STAT transcription complexes drive early and delayed responses to type I Interferons

    PubMed Central

    Plumlee, Courtney R.; Perry, Stuart; Gu, Ai Di; Lee, Carolyn; Shresta, Sujan; Decker, Thomas; Schindler, Christian

    2015-01-01

    Interferons, which transduce pivotal signals through signal transducer and activator of transcription (Stat)1 and Stat2, effectively suppress the replication of Legionella pneumophila in primary murine macrophages. Whereas the ability of IFN-γ to impede L. pneumophila growth is fully dependent on Stat1, IFN-α/β unexpectedly suppresses L. pneumophila growth in both Stat1 and Stat2 deficient macrophages. New studies demonstrating that the robust response to IFN-α/β is lost in Stat1-Stat2 double knockout macrophages, suggest that Stat1 and Stat2 are functionally redundant in their ability to direct an innate response towards L. pneumophila. Since the ability of IFN-α/β to signal through Stat1-dependent complexes (i.e., Stat1-Stat1 and Stat1-Stat2 dimers) has been well characterized, the current studies focus on how Stat2 is able to direct a potent response to IFN-α/β in the absence of Stat1. These studies reveal that IFN-α/β is able to drive the formation of a Stat2 and IRF9 complex that drives the expression of a subset of IFN stimulated genes (ISGs), but with substantially delayed kinetics. These observations raise the possibility that this pathway evolved in response to microbes that have devised strategies to subvert Stat1 dependent responses. PMID:26019270

  6. PMA activates Stat3 in the Jak/Stat pathway and induces SOCS5 in rat brain astrocytes.

    PubMed

    Hwang, Mi-Na; Kim, Kwang Soo; Choi, Yo-Woo; Jou, Ilo; Yoon, Sungpil

    2007-02-28

    Suppressors of cytokine signaling (SOCS) family members are negative feedback regulators of the Jak/Stat pathway, which is an essential inflammatory signaling pathway. We investigated expression of eight members of the SOCS family in rat astrocytes, using two inflammatory stimulants, PMA and IFN-gamma. Only a few SOCS genes were induced by both stimulants, and we detected an increase in SOCS5 protein with PMA. PMA activated the Jnk, Erk, p38, and Jak/Stat signal pathways. In addition, it increased the level of activated-Stat3 resulting from tyrosine phosphorylation. A gel-shift assay showed that a protein in nuclear extracts from PMA-treated cells was able to bind to Stat binding elements. These results suggest that activated Stat3 binds to SOCS promoters and leads to their transcriptional induction. PMID:17464217

  7. Human papillomavirus infection correlates with inflammatory Stat3 signaling activity and IL-17 expression in patients with breast cancer

    PubMed Central

    Zhang, Nan; Ma, Zhi Ping; Wang, Ju; Bai, Hui Li; Li, Yi Xin; Sun, Qin; Yang, Lan; Tao, Lin; Zhao, Jin; Cao, Yu Wen; Li, Feng; Zhang, Wen Jie

    2016-01-01

    Objectives: Microbiota has been suggested in promoting chronic inflammation in human tissues which, in turn, promotes tumor development. This study tests a hypothesis that high-risk human papillomavirus (HR-HPV) infection may correlate with proinflammatory Stat3 signaling activities and IL-17 levels in breast cancer (BC) patients. Materials and methods: This study examined HPV infection by GenChip technology, constitutively active Stat3 (p-Stat3) and IL-17 levels by immunohistochemistry (IHC) using specific antibodies in 379 BC patients, together with 245 paired adjacent breast adenosis (ABA) tissues and 100 unrelated breast adenosis (BA) tissues. Results: We obtained four major findings: (1) HR-HPV16/18 infections existed in 10.5% (34/325) of BC issues, higher than control BA tissues (4%, 4/100, P = 0.047). (2) Using IHC methodology, BC tissues showed more overactive p-Stat3 (2+/3+, 38.5%, 146/379) than ABA tissues (27.3%, 67/245, P < 0.001); similarly, BC also had more tissues overexpressing IL-17 (2+/3+, 61.5%, 233/379) than ABA tissues (51.8%, 127/245, P < 0.001). (3) High levels (2+/3+) of both active p-Stat3 and IL-17 correlated with poor differentiation and lymph nodal metastasis in BC (both with P < 0.05), but not with patients’ prognosis. (4) HR-HPV infections correlated with both active p-Stat3 (P = 0.018) and its downstream IL-17 levels (P = 0.021) in BC tissues. Conclusion: There may be a possible tri-lateral relationship among HPV infection, constitutive Stat3 activity and IL-17 level, whose collaborations could orchestrate a proinflammatory microenvironment in breast tissues by which promote carcinogenesis and/or facilitate progression of breast cancer. PMID:27508043

  8. Recombinant outer membrane protein C of Aeromonas hydrophila elicits mixed immune response and generates agglutinating antibodies.

    PubMed

    Yadav, Sunita Kumari; Meena, Jitendra Kumar; Sharma, Mahima; Dixit, Aparna

    2016-08-01

    Aeromonas hydrophila is a gram-negative fish pathogenic bacterium, also responsible for causing opportunistic pathological conditions in humans. It causes a number of diseases in fish due to which the fish industry incurs huge economic losses annually. Due to problems of antibiotic resistance, and the rapidity with which the infection spreads among fishes, vaccination remains the most effective strategy to combat this infection in fish populations. Among various virulence factors associated with bacterial virulence, outer membrane proteins have been widely evaluated for their vaccine potential owing to their surface exposure and related role in pathogenicity. In the present study, we have investigated the immunogenic potential of a non-specific porin, outer membrane protein C (OmpC) whose expression is regulated by the two-component regulatory system and plays a major role in the survival of A. hydrophila under different osmolaric conditions. The full-length gene (~1 kb) encoding OmpC of A. hydrophila was cloned, characterized and expressed in E. coli. High yield (~112 mg/L at shake flask level) of the recombinant OmpC (rOmpC) (~40 kDa) of A. hydrophila was obtained upon purification from inclusion bodies using Ni(2+)-NTA affinity chromatography. Immunization with purified rOmpC in murine model generated high endpoint (>1:40,000) titers. IgG isotyping, ELISA and ELISPOT assay indicated mixed immune response with a TH2 bias. Also, the anti-rOmpC antibodies were able to agglutinate A. hydrophila in vitro and exhibited specific cross-reactivity with different Aeromonas strains, which will facilitate easy detection of different Aeromonas isolates in infected samples. Taken together, these data clearly indicate that rOmpC could serve as an effective vaccine against different strains of Aeromonas, a highly heterogenous group of bacteria. PMID:27328672

  9. Altered interleukin-12 responsiveness in Th1 and Th2 cells is associated with the differential activation of STAT5 and STAT1.

    PubMed

    Gollob, J A; Murphy, E A; Mahajan, S; Schnipper, C P; Ritz, J; Frank, D A

    1998-02-15

    T-cell activation in response to interleukin-12 (IL-12) is mediated through signaling events that include the tyrosine phosphorylation of STAT4. IL-12 responsiveness and the ability of IL-12 to activate STAT4 is different in T cells induced to differentiate into a Th1 or Th2 phenotype. In this report, we show that STAT5, STAT1alpha, and STAT1beta, in addition to STAT4, are tyrosine phosphorylated in response to IL-12 in phytohemagglutinin (PHA)-activated human T cells. To understand how the activation of these STATs contributes to T-cell IL-12 responsiveness, we analyzed the IL-12-induced activation of STAT5 and STAT1 in T cells stimulated to undergo Th1 or Th2 differentiation. The IL-12-induced tyrosine phosphorylation of STAT5 and STAT1, but not STAT4, is augmented in T cells activated into Th1 cells with PHA + interferon-gamma (IFN-gamma) compared with T cells activated with PHA alone. STAT5 DNA binding induced by IL-12 is also augmented in T cells activated with PHA + IFN-gamma compared with T cells activated with PHA alone, whereas STAT4 DNA binding is not increased. In contrast, the IL-12-induced activation of these STATs is inhibited in T cells activated into Th2 cells with PHA + IL-4. The enhancement of IL-12 signaling by IFN-gamma is not a direct effect of IFN-gamma on T cells, but rather is mediated by IL-12 that is produced by antigen-presenting cells in response to IFN-gamma. This positive autoregulatory effect of IL-12 on the activation of select STATs correlates with an increase in T-cell IFN-gamma production in response to IL-12. These findings suggest that the activation of STAT5 and STAT1 may augment select STAT4-dependent functional responses to IL-12 in Th1 cells. PMID:9454765

  10. JAK/STAT/SOCS-signaling pathway and colon and rectal cancer

    PubMed Central

    Slattery, Martha L.; Lundgreen, Abbie; Kadlubar, Susan A.; Bondurant, Kristina L.; Wolff, Roger K.

    2012-01-01

    The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway is involved in immune function and cell growth. We evaluated the association between genetic variation in JAK1 (10 SNPs), JAK2 (9 SNPs), TYK2 (5 SNPs), SOCS1 (2 SNPs), SOCS2 (2 SNPs), STAT1 (16 SNPs), STAT2 (2 SNPs), STAT3 (6 SNPs), STAT4 (21 SNPs), STAT5A (2 SNPs), STAT5B (3 SNPs), STAT6 (4 SNPs) with risk of colorectal cancer. We used data from population-based case-control studies (colon cancer n=1555 cases, 1956 controls; rectal cancer n=754 cases, 959 controls). JAK2, SOCS2, STAT1, STAT3, STAT5A, STAT5B, and STAT6 were associated with colon cancer; STAT3, STAT4, STAT6, and TYK2 were associated with rectal cancer. Given the biological role of the JAK/STAT-signaling pathway and cytokines, we evaluated interaction with IFNG, TNF, and IL6; numerous statistically significant associations after adjustment for multiple comparisons were observed. The following statistically significant interactions were observed: TYK2 with aspirin/NSAID use; STAT1, STAT4, and TYK2 with estrogen status; and JAK2, STAT2, STAT4, STAT5A, STAT5B, and STAT6 with smoking status and colon cancer risk; JAK2, STAT6, and TYK2 with aspirin/NSAID use; JAK1 with estrogen status; STAT2 with cigarette smoking and rectal cancer. JAK2, SOCS1, STAT3, STAT5, and TYK2 were associated with colon cancer survival (HRR of 3.3 95% CI 2.01, 5.42 for high mutational load). JAK2, SOCS1, STAT1, STAT4, and TYK2 were associated with rectal cancer survival (HRR 2.80 95 %CI 1.63, 4.80). These data support the importance of the JAK/STAT-signaling pathway in colorectal cancer and suggest targets for intervention. PMID:22121102

  11. Idiopathic pancreatitis in a patient with a STAT3 mutation

    PubMed Central

    Peppers, Brian; Frith, John; Tcheurekdjian, Haig; Hostoffer, Robert

    2016-01-01

    Background: Hyperimmunoglobulin E syndrome (HIES) is a rare primary immunodeficiency characterized by recurrent skin infections with abscesses, recurrent pneumonias with pneumatoceles, and immunoglobulin E levels of >10 times the upper limit of normal. Case: The patient described herein had a classic case of signal transducer and activator of transcription 3 (STAT3) deficiency associated with HIES diagnosed several years before this particular presentation. He demonstrated extraimmune manifestations of the disease as well, including characteristic facies and a history of skeletal fractures. In addition, the patient had several distinct episodes of idiopathic pancreatitis for which a full gastrointestinal workup had been performed. STAT3 mutation was confirmed by genotyping at the time of diagnosis of HIES. Conclusions: STAT3, a mammalian protein that regulates cell growth, survival, and differentiation, has been linked to human pancreatic carcinogenesis as well as the above-mentioned immune deficiency. Mouse studies demonstrated that genetic ablation of STAT3 exacerbates the course of acute pancreatitis, whereas normal pancreatic STAT3 seems to have a protective effect against necrotizing pancreatitis. An association between STAT3 mutations and pancreatitis has not yet been revealed in humans. Here we describe a case of acute pancreatitis that presented in a patient with STAT3 mutation. PMID:27103560

  12. Resveratrol and STAT inhibitor enhance autophagy in ovarian cancer cells

    PubMed Central

    Zhong, L-X; Zhang, Y; Wu, M-L; Liu, Y-N; Zhang, P; Chen, X-Y; Kong, Q-Y; Liu, J; Li, H

    2016-01-01

    Autophagic activity reflects cellular response to drug treatment and can be regulated by STAT3 signaling. Resveratrol inhibits STAT3 activation and causes remarkable growth arrest and cell death of ovarian cancer (OC) cells. However, the autophagic status and its relevance with resveratrol’s anti-OC effects remain unclear. We analyzed the states of autophagic activities, the nature of autophagosomes and the levels of autophagy-related proteins (LC-3, Beclin 1 and STAT3) in resveratrol-treated CAOV-3 and OVCAR-3 OC cells using multiple approaches. We elucidated the correlation of STAT3 inhibition with autophagic activity by treating OC cells with an upstream inhibitor of STAT proteins, AG490. Resveratrol efficiently suppressed growth, induced apoptosis and inactivated STAT3 signaling of the two OC cell lines. We found enhanced autophagic activity accompanied with Beclin-1 upregulation and LC3 enzymatic cleavage in resveratrol-treated OC cells. Immunofluorescent (IF) microscopic and IF-based confocal examinations demonstrated the accumulation of cytoplasmic granules co-labeled with LC3 and cytochrome C in resveratrol- or AG490-treated OC cells. Using electron microscopy, we confirmed an increase in autophagosomes and mitochondrial spheroids in either resveratrol- or AG490-treated OC cells. This study demonstrates the abilities of resveratrol to enhance apoptotic and autophagic activities in OC cells, presumably via inactivating STAT3 signaling. Resveratrol or the selective JAK2 inhibitor also leads to mitochondrial turnover, which would be unfavorable for OC cell survival and sensitize OC cells to resveratrol. PMID:27551495

  13. Inhibition of STAT5: A therapeutic option in BCR-ABL1-driven leukemia

    PubMed Central

    Berger, Angelika; Sexl, Veronika; Valent, Peter; Moriggl, Richard

    2014-01-01

    The two transcription factors STAT5A and STAT5B are central signaling molecules in leukemias driven by Abelson fusion tyrosine kinases and they fulfill all criteria of drug targets. STAT5A and STAT5B display unique nuclear shuttling mechanisms and they have a key role in resistance of leukemic cells against treatment with tyrosine kinase inhibitors (TKI). Moreover, STAT5A and STAT5B promote survival of leukemic stem cells. We here discuss the possibility of targeting up-stream kinases with TKI, direct STAT5 inhibition via SH2 domain obstruction and blocking nuclear translocation of STAT5. All discussed options will result in a stop of STAT5 transport to the nucleus to block STAT5-mediated transcriptional activity. In summary, recently described shuttling functions of STAT5 are discussed as potentially druggable pathways in leukemias. PMID:25333255

  14. Hyperactivated Stat3 boosts axon regeneration in the CNS.

    PubMed

    Mehta, Saloni T; Luo, Xueting; Park, Kevin K; Bixby, John L; Lemmon, Vance P

    2016-06-01

    Axonal regeneration after spinal cord injury (SCI) is intrinsically and extrinsically inhibited by multiple factors. One major factor contributing to intrinsic regeneration failure is the inability of mature neurons in the central nervous system (CNS) to activate regeneration-associated transcription factors (TFs) post-injury. A prior study identified TFs overexpressed in neurons of the peripheral nervous system (PNS) compared to the CNS; some of these could be involved in the ability of PNS neurons to regenerate. Of these, signal transducer and activator of transcription 3 (STAT3), as well its downstream regeneration-associated targets, showed a significant upregulation in PNS neurons relative to CNS neurons, and a constitutively active variant of Stat3 (Stat3CA) promoted neurite growth when expressed in cerebellar neurons (Lerch et al., 2012; Smith et al., 2011). To further enhance STAT3's neurite outgrowth enhancing activity, Stat3CA was fused with a viral activation domain (VP16). VP16 hyperactivates TFs by recruiting transcriptional co-factors to the DNA binding domain (Hirai et al., 2010). Overexpression of this VP16-Stat3CA chimera in primary cortical neurons led to a significant increase of neurite outgrowth as well as Stat3 transcriptional activity in vitro. Furthermore, in vivo transduction of retinal ganglion cells (RGCs) with AAV constructs expressing VP16-Stat3CA resulted in regeneration of optic nerve axons after injury, to a greater degree than for those expressing Stat3CA alone. These findings confirm and extend the concept that overexpression of hyperactivated transcription factors identified as functioning in PNS regeneration can promote axon regeneration in the CNS. PMID:27060489

  15. Piperlongumine Blocks JAK2-STAT3 to Inhibit Collagen-Induced Platelet Reactivity Independent of Reactive Oxygen Species†

    PubMed Central

    Yuan, Hengjie; Houck, Katie L.; Tian, Ye; Bharadwaj, Uddalak; Hull, Ken; Zhou, Zhou; Zhou, Mingzhao; Wu, Xiaoping; Tweardy, David J.; Romo, Daniel; Fu, Xiaoyun; Zhang, Yanjun; Zhang, Jianning; Dong, Jing-fei

    2015-01-01

    Background Piperlongumine (PL) is a compound isolated from the piper longum plant. It possesses anti-cancer activities through blocking the transcription factor STAT3 and by inducing reactive oxygen species (ROS) in cancer, but not normal cells. It also inhibits platelet aggregation induced by collagen, but the underlying mechanism is not known. Objective We conducted in vitro experiments to test the hypothesis that PL regulates a non-transcriptional activity of STAT3 to specifically reduce the reactivity of human platelets to collagen. Results PL dose-dependently blocked collagen-induced platelet aggregation, calcium influx, CD62p expression and thrombus formation on collagen with a maximal inhibition at 100 μM. It reduced platelet microvesiculation induced by collagen. PL blocked the activation of JAK2 and STAT3 in collagen-stimulated platelets. This inhibitory effect was significantly reduced in platelets pretreated with a STAT3 inhibitor. Although PL induced ROS production in platelets; quenching ROS using excessive reducing agents: 20 μM GSH and 0.5 mM L-Cysteine, did not block the inhibitory effects. The NADPH oxidase inhibitor Apocynin also had no effect. Conclusions PL inhibited collagen-induced platelet reactivity by targeting the JAK2-STAT3 pathway. We also provide experimental evidence that PL and collagen induce different oxidants that have differential effects on platelets. Studying these differential effects may uncover new mechanisms of regulating platelet functions by oxidants in redox signals. PMID:26645674

  16. STAT3 inhibitor WP1066 as a novel therapeutic agent for bCCI neuropathic pain rats.

    PubMed

    Xue, Zhao-Jing; Shen, Le; Wang, Zhi-Yao; Hui, Shang-Yi; Huang, Yu-Guang; Ma, Chao

    2014-10-01

    Activation of signal transducer and activator of transcription-3 (STAT3) is suggested to be critically involved in the development of chronic pain, but the complex regulation of STAT3-dependent pathway and the functional significance of inhibiting this pathway during the development of neuropathic pain remain elusive. To evaluate the contribution of the JAK2/STAT3 pathway to neuropathic pain and the potentiality of this pathway as a novel therapeutic target, we examined the effects of the STAT3 inhibitor WP1066 by intrathecal administration in a rat model of bilateral chronic constriction injury (bCCI). The pain behavior tests were performed before the surgery and on postoperative day 3, 7, 14 and 21. L4-L6 dorsal spinal cord were harvested at each time point. Both RT-PCR and Western blot were performed to evaluate the activation of JAK2/STAT3 pathway. To observe the influence of WP1066 on neuropathic pain and its molecular mechanism, WP1066 (10 μl, 10 mmol/L in DMSO) or the same capacity of DMSO as the control were applied through the intrathecal tube on the day before bCCI surgery, and on the postoperative day 3 and 5. Behavioral tests were performed to observe the therapeutic effect on mechanical, thermal and cold hyperalgesia. L4-L6 dorsal spinal cord was harvested on postoperative day fourteen, followed by RT-PCR and Western blot evaluation of the JAK2/STAT3 pathway activation. The mechanical, thermal and cold hyperalgesia of the bCCI rats were significantly decreased when compared with the Sham or the Naïve group at each postoperative time point (P<0.05). JAK2 mRNA and STAT3 mRNA were significantly increased in the bCCI rats, accompanied by SOCS3 mRNA with a similar tendency. Western blot analysis showed that JAK2 and phosphorylated STAT3 increased significantly since 3 days after bCCI. JAK2 peaked on postoperative day 14 while phosphorylated STAT3 peaked on postoperative day 7 and gradually decreased thereafter and SOCS3׳s peak level on postoperative day

  17. A membrane penetrating peptide aptamer inhibits STAT3 function and suppresses the growth of STAT3 addicted tumor cells

    PubMed Central

    Borghouts, Corina; Delis, Natalia; Brill, Boris; Weiss, Astrid; Mack, Laura; Lucks, Peter; Groner, Bernd

    2012-01-01

    Cancer cells are characterized by the aberrant activation of signaling pathways governing proliferation, survival, angiogenesis, migration and immune evasion. These processes are partially regulated by the transcription factor STAT3. This factor is inappropriately activated in diverse tumor types. Since tumor cells can become dependent on its persistent activation, STAT3 is a favorable drug target. Here, we describe the functional characterization of the recombinant STAT3 inhibitor, rS3-PA. This inhibitor is based on a 20 amino acid peptide which specifically interacts with the dimerization domain of STAT3. It is integrated into a thioredoxin scaffold and fused to a protein transduction domain. Protein gel blot and immunofluorescence analyses showed that rS3-PA is efficiently taken up by cells via an endocytosis independent mechanism. Intracellularly, it reduces the phosphorylation of STAT3 and enhances its degradation. This leads to the downregulation of STAT3 target gene expression on the mRNA and protein levels. Subsequently, tumor cell proliferation, survival and migration and the induction of angiogenesis are inhibited. In contrast, normal cells remain unaffected. Systemic administration of rS3-PA at doses of 7.5 mg/kg reduced P-STAT3 levels and significantly inhibited tumor growth up to 35% in a glioblastoma xenograft mouse model. PMID:24058750

  18. The lipopolysaccharide (R type) as a common antigen of Neisseria gonorrhoeae. II. Use of hen antiserum to gonococcal lipopolysaccharide in a rapid slide test for the identification of N. gonorrhoeae from primary isolates and secondary cultures.

    PubMed

    Wallace, R; Ashton, F E; Ryan, A; Diena, B B

    1978-02-01

    An antiserum has been prepared in hens to R-type gonococcal lipopolysaccharide (LPS) and used in a simple slide-agglutination test for the identification of Neisseria gonorrhoeae. Anti-LPS serum agglutinated gonococcal cells representative of the four colony types of N. gonorrhoeae. Absorption of the antiserum with LPS removed the agglutinating activity. Secondary cultures (1120) were tested without observation of the colony type and all were agglutinated. No agglutination occurred with strains of Neisseria meningitidis, Neisseria lactamica, non-pathogenic Neisseria. Pseudomonas aeruginosa, Branhamella catarrhalis, or with species of lactobacilli and Acinetobacter. Cross-reactivity of the antiserum occurred with some streptococci. The anti-LPS serum was used to identify N. gonorrhoeae in primary isolates from the cervix, urethra, and pharynx. Of 251 gonococcal isolates tested, 249 were agglutinated by the antiserum, while all of the corresponding second cultures were agglutinated. The antiserum did not agglutinate N. meningitidis found in primary isolates from pharyngeal specimens. Anti-LPS hen serum should be useful for the rapid identification of N. gonorrhoeae in primary isolates or secondary cultures. PMID:417781

  19. Crystal structure of a platelet-agglutinating factor isolated from the venom of Taiwan habu (Trimeresurus mucrosquamatus).

    PubMed Central

    Huang, Kai-Fa; Ko, Tzu-Ping; Hung, Chin-Chun; Chu, John; Wang, Andrew H-J; Chiou, Shyh-Horng

    2004-01-01

    Platelet glycoprotein Ib (GPIb)-binding proteins (GPIb-BPs) from snake venoms are usually C-type lectins, which target specific sites of GPIbalpha and elicit distinct effects on platelets. In the present paper, we report a tetrameric platelet-agglutinating factor (molecular mass 121.1 kDa), termed mucrocetin, purified from the venom of Taiwan habu (Trimeresurus mucrosquamatus ). Mucrocetin is a GPIbalpha agonist with a binding site distinct from that of flavocetin-A (a snake venom GPIbalpha antagonist) on GPIbalpha, in spite of the high sequence identity (94.6%) between the two venom lectins. The crystal structure of mucrocetin was solved and refined to 2.8 A (1 A=0.1 nm) resolution, which shows an interesting crystal packing of six-layer cylinders of doughnut-shaped molecules. The four alphabeta heterodimers are arranged in an unusual square-shaped ring stabilized by four interdimer 'head-to-tail' disulphide bridges. Detailed structural comparison between mucrocetin and flavocetin-A suggests that their disparate platelet effects are probably attributable to different charge distributions on the putative concave binding surface. A unique positively charged patch on the binding surface of mucrocetin, formed by Lys102, Lys108, Lys109 and Arg123 in the alpha-subunit coupled with Lys22, Lys102, Lys116 and Arg117 in the beta-subunit, appears to be the primary determinant of its platelet-agglutinating activity. Conceivably, this interesting venom factor may provide a useful tool to study platelet agglutination by binding to the GPIb-IX-V complex. PMID:14613481

  20. FastStats: Health of Mexican American Population

    MedlinePlus

    ... Death Life Expectancy Race and Ethnicity Health of American Indian or Alaska Native Population Health of Asian or ... 1 [PDF - 993 KB] Related FastStats Health of American Indian or Alaska Native Population Health of Asian or ...

  1. PhenStat: A Tool Kit for Standardized Analysis of High Throughput Phenotypic Data

    PubMed Central

    Kurbatova, Natalja; Mason, Jeremy C.; Morgan, Hugh; Meehan, Terrence F.; Karp, Natasha A.

    2015-01-01

    The lack of reproducibility with animal phenotyping experiments is a growing concern among the biomedical community. One contributing factor is the inadequate description of statistical analysis methods that prevents researchers from replicating results even when the original data are provided. Here we present PhenStat – a freely available R package that provides a variety of statistical methods for the identification of phenotypic associations. The methods have been developed for high throughput phenotyping pipelines implemented across various experimental designs with an emphasis on managing temporal variation. PhenStat is targeted to two user groups: small-scale users who wish to interact and test data from large resources and large-scale users who require an automated statistical analysis pipeline. The software provides guidance to the user for selecting appropriate analysis methods based on the dataset and is designed to allow for additions and modifications as needed. The package was tested on mouse and rat data and is used by the International Mouse Phenotyping Consortium (IMPC). By providing raw data and the version of PhenStat used, resources like the IMPC give users the ability to replicate and explore results within their own computing environment. PMID:26147094

  2. IL-6 blockade reverses the abnormal STAT activation of peripheral blood leukocytes from rheumatoid arthritis patients.

    PubMed

    Ortiz, M A; Diaz-Torné, C; Hernández, M V; Reina, D; de la Fuente, D; Castellví, I; Moya, P; Ruiz, J M; Corominas, H; Zamora, C; Cantó, E; Sanmartí, R; Juarez, C; Vidal, S

    2015-06-01

    Considering the interplay of multiple STATs in response to cytokines, we investigated how IL-6 and its blocking affect STAT signaling in rheumatoid arthritis (RA). Leukocytes obtained from RA patients before and after tocilizumab treatment and healthy donors (HDs) were cytokine-stimulated and STAT phosphorylation was analyzed by cytometry. RA patients had significantly fewer pSTAT1+, pSTAT3+, and pSTAT6+ monocytes and pSTAT5+ lymphocytes than HDs. After 24weeks of treatment, percentages of IFNγ-induced pSTAT1+ and IL-10-induced pSTAT3+ monocytes in RA patients increased, reaching levels comparable to HDs. pSTAT1+ and pSTAT3+ cells correlated inversely with RA disease activity index and levels of pSTAT+ cells at baseline were higher in patients with good EULAR response to tocilizumab. IFNγ-induced pSTAT1+ cells correlated inversely with memory T cells and anti-CCP levels. IL-10-induced pSTAT3+ cells correlated with Treg/Teff ratio. Our findings suggest that IL-6 blocking reduces the inflammatory mechanisms through the correction of STAT1 and STAT3 activation status. PMID:25847223

  3. A new type of pseudothrombocytopenia: EDTA-mediated agglutination of platelets bearing Fab fragments of a chimaeric antibody.

    PubMed

    Christopoulos, C G; Machin, S J

    1994-07-01

    In vitro agglutination of platelets leading to low automated platelet counts was observed in EDTA-anticoagulated blood from human volunteers receiving infusions of Fab fragments of a chimaeric monoclonal antibody to platelet glycoprotein IIb-IIIa. This pseudothrombocytopenia depended on the presence of chimaeric Fab on the platelet surface and was not seen when sodium citrate was used as anticoagulent. Preliminary evidence suggests that this phenomenon might be mediated by immunoglobulin G reactive with the human component of the chimaeric Fab. It is important to exclude pseudothrombocytopenia when low automated platelet counts are reported in association with the administration of chimaeric anti-platelet antibodies. PMID:7993813

  4. Somatic STAT3 Mutations in Large Granular Lymphocytic Leukemia

    PubMed Central

    Koskela, Hanna L.M.; Eldfors, Samuli; Ellonen, Pekka; van Adrichem, Arjan J.; Kuusanmäki, Heikki; Andersson, Emma I.; Lagström, Sonja; Clemente, Michael J.; Olson, Thomas; Jalkanen, Sari E.; Majumder, Muntasir Mamun; Almusa, Henrikki; Edgren, Henrik; Lepistö, Maija; Mattila, Pirkko; Guinta, Kathryn; Koistinen, Pirjo; Kuittinen, Taru; Penttinen, Kati; Parsons, Alun; Knowles, Jonathan; Saarela, Janna; Wennerberg, Krister; Kallioniemi, Olli; Porkka, Kimmo; Loughran, Thomas P.; Heckman, Caroline A.; Maciejewski, Jaroslaw P.; Mustjoki, Satu

    2013-01-01

    BACKGROUND T-cell large granular lymphocytic leukemia is a rare lymphoproliferative disorder characterized by the expansion of clonal CD3+CD8+ cytotoxic T lymphocytes (CTLs) and often associated with autoimmune disorders and immune-mediated cytopenias. METHODS We used next-generation exome sequencing to identify somatic mutations in CTLs from an index patient with large granular lymphocytic leukemia. Targeted resequencing was performed in a well-characterized cohort of 76 patients with this disorder, characterized by clonal T-cell–receptor rearrangements and increased numbers of large granular lymphocytes. RESULTS Mutations in the signal transducer and activator of transcription 3 gene (STAT3) were found in 31 of 77 patients (40%) with large granular lymphocytic leukemia. Among these 31 patients, recurrent mutational hot spots included Y640F in 13 (17%), D661V in 7 (9%), D661Y in 7 (9%), and N647I in 3 (4%). All mutations were located in exon 21, encoding the Src homology 2 (SH2) domain, which mediates the dimerization and activation of STAT protein. The amino acid changes resulted in a more hydrophobic protein surface and were associated with phosphorylation of STAT3 and its localization in the nucleus. In vitro functional studies showed that the Y640F and D661V mutations increased the transcriptional activity of STAT3. In the affected patients, downstream target genes of the STAT3 pathway (IFNGR2, BCL2L1, and JAK2) were up-regulated. Patients with STAT3 mutations presented more often with neutropenia and rheumatoid arthritis than did patients without these mutations. CONCLUSIONS The SH2 dimerization and activation domain of STAT3 is frequently mutated in patients with large granular lymphocytic leukemia; these findings suggest that aberrant STAT3 signaling underlies the pathogenesis of this disease. (Funded by the Academy of Finland and others.) PMID:22591296

  5. Development of T-STAT for Early Autism Screening

    ERIC Educational Resources Information Center

    Chiang, Chung-Hsin; Wu, Chin-Chin; Hou, Yuh-Ming; Chu, Ching-Lin; Liu, Jiun-Horng; Soong, Wei-Tsuen

    2013-01-01

    This study's purpose was to modify the Screening Tool for Autism in Two-Year-Olds (STAT) into a Taiwanese version called T-STAT. Study 1 included 15 children with Autism and 15 children with Developmental Delay (DD) or language impairment (LI) aged between 24 and 35 months. Study 2 had 77 young children with Autism, PDD-NOS, or DD/LI as a…

  6. Deletion of Intestinal Epithelial Cell STAT3 Promotes T Lymphocyte STAT3 Activation and Chronic Colitis Following Acute Dextran Sodium Sulfate Injury in Mice

    PubMed Central

    Willson, Tara A.; Jurickova, Ingrid; Collins, Margaret; Denson, Lee A.

    2015-01-01

    BACKGROUND Intestinal epithelial cell (IEC) Stat3 is required for wound healing following acute Dextran Sodium Sulfate (DSS) injury. We hypothesized that loss of IEC STAT3 would promote the development of chronic colitis following acute DSS injury. METHODS Colitis was induced in IEC-specific Stat3 deficient mice (Stat3ΔIEC) and littermate controls (Stat3Flx/Flx) with 4%DSS for 7 days, followed by water consumption for 21 days. Epithelial and immune mediators and severity of colitis were determined. RESULTS Survival, colon length, and histologic injury were significantly worse at day 28 in Stat3ΔIEC mice. IEC proliferation and apoptosis did not vary by genotype at day 14 or day 28. The colonic lamina propria frequency of pSTAT3+ cells was increased at day 28 and correlated with histologic injury in Stat3ΔIEC mice. The frequency of colonic F480+pSTAT3+ macrophages and CD3+pSTAT3+ T-lymphocytes were increased in Stat3ΔIEC mice as compared to Stat3Flx/Flx controls. In Stat3ΔIEC mice, colonic expression of Stat3 target genes Reg3β and Reg3γ which mediate epithelial restitution were significantly decreased, while expression of IL-17a, IFNγ, CXCL2, CXCL10, and CCL2 were significantly increased and correlated with the increase in histologic severity at Day 28(p<.05). IL-17a expression also correlated with the increased lamina propria frequency of CD3+pSTAT3+ T-lymphocytes. CONCLUSIONS Loss of intestinal epithelial Stat3 leads to more severe chronic inflammation following acute injury which is not accounted for by a sustained defect in epithelial proliferation or apoptosis 7 or 21 days after one cycle of DSS but rather defective REG3 expression and expansion of pSTAT3+ lymphocytes and IL-17a expression. PMID:23429443

  7. Cooperative DNA Binding and Sequence-Selective Recognition Conferred by the STAT Amino-Terminal Domain

    NASA Astrophysics Data System (ADS)

    Xu, Xiang; Sun, Ya-Lin; Hoey, Timothy

    1996-08-01

    STAT proteins (signal transducers and activators of transcription) activate distinct target genes despite having similar DNA binding preferences. The transcriptional specificity of STAT proteins was investigated on natural STAT binding sites near the interferon-gamma gene. These sites are arranged in multiple copies and required cooperative interactions for STAT binding. The conserved amino-terminal domain of STAT proteins was required for cooperative DNA binding, although this domain was not essential for dimerization or binding to a single site. Cooperative binding interactions enabled the STAT proteins to recognize variations of the consensus site. These sites can be specific for the different STAT proteins and may function to direct selective transcriptional activation.

  8. STAT Signaling in Different Breast Cancer Sub-types

    PubMed Central

    Furth, Priscilla A.

    2013-01-01

    This review summarizes information on expression of Signal Transducer and Activator of Transcription (STAT)s 1, 2, 3, 4, 5a/b and 6 in cancer cells from different human breast cancer sub-types. STAT proteins, especially STATs 1,3 and 5a/b are expressed in some but not all cancers from all of the different major breast cancer sub-types. However, well-designed studies comparing expression patterns at the protein level in cancer and surrounding stromal cells are still needed to fully examine links with prognosis and therapeutic response. Moreover, it is not yet known if distinct expression patterns of STAT proteins could have dissimilar impacts in different sub-types, especially between the luminal A and B ER+ sub-types and the different TNBC sub-types. Recent data indicating that STAT5 can be activated secondary to a therapeutic intervention and mediate resistance suggests that expression patterns should not only be examined in pre-treatment but also post-treatment samples from different sub-types. PMID:23562422

  9. Stat1 Nuclear Translocation by Nucleolin upon Monocyte Differentiation

    PubMed Central

    Jerke, Uwe; Tkachuk, Sergey; Kiyan, Julia; Stepanova, Victoria; Kusch, Angelika; Hinz, Michael; Dietz, Rainer; Haller, Hermann; Fuhrman, Bianca; Dumler, Inna

    2009-01-01

    Background Members of the signal transducer and activator of transcription (Stat) family of transcription factors traverse the nuclear membrane through a specialized structure, called the nuclear pore complex (NPC), which represents a selective filter for the import of proteins. Karyophilic molecules can bind directly to a subset of proteins of the NPC, collectively called nucleoporins. Alternatively, the transport is mediated via a carrier molecule belonging to the importin/karyopherin superfamily, which transmits the import into the nucleus through the NPC. Methodology/Principal Findings In this study, we provide evidence for an alternative Stat1 nuclear import mechanism, which is mediated by the shuttle protein nucleolin. We observed Stat1-nucleolin association, nuclear translocation and specific binding to the regulatory DNA element GAS. Using expression of nucleolin transgenes, we found that the nuclear localization signal (NLS) of nucleolin is responsible for Stat1 nuclear translocation. We show that this mechanism is utilized upon differentiation of myeloid cells and is specific for the differentiation step from monocytes to macrophages. Conclusions/Significance Our data add the nucleolin-Stat1 complex as a novel functional partner for the cell differentiation program, which is uniquely poised to regulate the transcription machinery via Stat1 and nuclear metabolism via nucleolin. PMID:20011528

  10. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis

    PubMed Central

    Haricharan, S; Li, Y

    2013-01-01

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, programed cell death and stromal reorganization to clear the differentiated milk-producing cells. Not surprisingly, the signaling pathways responsible for bringing about these changes in breast cells are often subverted during the process of tumorigenesis. The STAT family of proteins is involved in every stage of mammary gland development, and is also frequently implicated in breast tumorigenesis. While the roles of STAT3 and STAT5 during mammary gland development and tumorigenesis are well studied, others members, e.g. STAT1 and STAT6, have only recently been observed to play a role in mammary gland biology. Continued investigation into the STAT protein network in the mammary gland will likely yield new biomarkers and risk factors for breast cancer, and may also lead to novel prophylactic or therapeutic strategies against breast cancer. PMID:23541951

  11. STAT3 in the systemic inflammation of cancer cachexia.

    PubMed

    Zimmers, Teresa A; Fishel, Melissa L; Bonetto, Andrea

    2016-06-01

    Weight loss is diagnostic of cachexia, a debilitating syndrome contributing mightily to morbidity and mortality in cancer. Most research has probed mechanisms leading to muscle atrophy and adipose wasting in cachexia; however cachexia is a truly systemic phenomenon. Presence of the tumor elicits an inflammatory response and profound metabolic derangements involving not only muscle and fat, but also the hypothalamus, liver, heart, blood, spleen and likely other organs. This global response is orchestrated in part through circulating cytokines that rise in conditions of cachexia. Exogenous Interleukin-6 (IL6) and related cytokines can induce most cachexia symptomatology, including muscle and fat wasting, the acute phase response and anemia, while IL-6 inhibition reduces muscle loss in cancer. Although mechanistic studies are ongoing, certain of these cachexia phenotypes have been causally linked to the cytokine-activated transcription factor, STAT3, including skeletal muscle wasting, cardiac dysfunction and hypothalamic inflammation. Correlative studies implicate STAT3 in fat wasting and the acute phase response in cancer cachexia. Parallel data in non-cancer models and disease states suggest both pathological and protective functions for STAT3 in other organs during cachexia. STAT3 also contributes to cancer cachexia through enhancing tumorigenesis, metastasis and immune suppression, particularly in tumors associated with high prevalence of cachexia. This review examines the evidence linking STAT3 to multi-organ manifestations of cachexia and the potential and perils for targeting STAT3 to reduce cachexia and prolong survival in cancer patients. PMID:26860754

  12. Curcumin suppresses invasiveness and vasculogenic mimicry of squamous cell carcinoma of the larynx through the inhibition of JAK-2/STAT-3 signaling pathway.

    PubMed

    Hu, An; Huang, Jing-Juan; Jin, Xiao-Jie; Li, Ji-Ping; Tang, Yuan-Jia; Huang, Xin-Fang; Cui, Hui-Juan; Xu, Wei-Hua; Sun, Guang-Bin

    2015-01-01

    To determine the role of JAK-2/STAT-3 signaling pathway in invasion and vasculogenic mimicry of laryngeal squamous cell carcinoma. HEp-2 cells were treated with 1 or 10 μmol/L curcumin and AG490 (the inhibitor of JAK-2) for 48 h, the invasion and vasculogenic mimicry of tumor cells were tested with Transwell chamber test and tube formation experiment. RT-PCR was used to measure the expression of MMP-2 and VEGF. Western blot assay was employed to determine the expression of JAK-2, STAT3, p-STAT3, MMP-2 and VEGF. Compared to control group,there were less tumor cells permeating membrane and less formed tubes after curcumin or AG490 treatment, RT-PCR showed that the expression of MMP-2 and VEGF at mRNA level were decreased (P < 0.01). Western blotting indicated that the expression of JAK-2, p-STAT3, MMP-2 and VEGF at protein levels were decreased (P < 0.01), while that of STAT-3 protein had no difference among each group (P > 0.05). Immunofluorescence staining demonstrated that the expression of eNOS was down-regulated (P < 0.01). Curcumin and AG490 significantly inhibits invasion and vasculogenic mimicry of laryngeal squamous cell carcinoma in vitro, and JAK-2/STAT-3 signaling pathway promotes above processes. PMID:25628937

  13. Differential Contribution of IL-4 and STAT6 vs STAT4 to the Development of Lupus Nephritis1

    PubMed Central

    Singh, Ram Raj; Saxena, Vijay; Zang, Song; Li, Lily; Finkelman, Fred D.; Witte, David P.; Jacob, Chaim O.

    2008-01-01

    Mechanisms that initiate lupus nephritis and cause progression to end-stage renal disease remain poorly understood. In this study, we show that lupus-prone New Zealand Mixed 2410 mice that develop a severe glomerulosclerosis and rapidly progressive renal disease overexpress IL-4 in vivo. In these mice, STAT6 deficiency or anti-IL-4 Ab treatment decreases type 2 cytokine responses and ameliorates kidney disease, particularly glomerulosclerosis, despite the presence of high levels of IgG anti-dsDNA Abs. STAT4 deficiency, however, decreases type 1 and increases type 2 cytokine responses, and accelerates nephritis, in the absence of high levels of IgG anti-dsDNA Abs. Thus, STAT6 and IL-4 may selectively contribute to the development of glomerulosclerosis, whereas STAT4 may play a role in autoantibody production. PMID:12707364

  14. Structural basis for recruitment of CBP/p300 coactivators by STAT1 and STAT2 transactivation domains

    PubMed Central

    Wojciak, Jonathan M; Martinez-Yamout, Maria A; Dyson, H Jane; Wright, Peter E

    2009-01-01

    CBP/p300 transcriptional coactivators mediate gene expression by integrating cellular signals through interactions with multiple transcription factors. To elucidate the molecular and structural basis for CBP-dependent gene expression, we determined structures of the CBP TAZ1 and TAZ2 domains in complex with the transactivation domains (TADs) of signal transducer and activator of transcription 2 (STAT2) and STAT1, respectively. Despite the topological similarity of the TAZ1 and TAZ2 domains, subtle differences in helix packing and surface grooves constitute major determinants of target selectivity. Our results suggest that TAZ1 preferentially binds long TADs capable of contacting multiple surface grooves simultaneously, whereas smaller TADs that are restricted to a single contiguous binding surface form complexes with TAZ2. Complex formation for both STAT TADs involves coupled folding and binding, driven by intermolecular hydrophobic and electrostatic interactions. Phosphorylation of S727, required for maximal transcriptional activity of STAT1, does not enhance binding to any of the CBP domains. Because the different STAT TADs recognize different regions of CBP/p300, there is a potential for multivalent binding by STAT heterodimers that could enhance the recruitment of the coactivators to promoters. PMID:19214187

  15. siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene

    NASA Astrophysics Data System (ADS)

    Minami, Kosuke; Okamoto, Koji; Doi, Kent; Harano, Koji; Noiri, Eisei; Nakamura, Eiichi

    2014-05-01

    The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications.

  16. Study of polycation effects on erythrocyte agglutination mediated by anti-glycophorins using microscopic image digital analysis

    NASA Astrophysics Data System (ADS)

    Riquelme, B.; Dumas, D.; Relancio, F.; Fontana, A.; Alessi, A.; Foresto, P.; Grandfils, C.; Stoltz, J.; Valverde, J.

    2006-04-01

    The aim of this work was to study synthetic polycation effects on erythrocyte agglutination mediated by anti-glycophorin using image digital analysis. Polycations are oligomers or polymers of natural or synthetic origin, which bear a great number of positive charges at pH 7.4. Several of these polycations are nowadays used in clinic for human and veterinary purposes. New applications of polycations to the development of new drug delivery systems are investigated, in order to promote the drug absorption through the gastro-intestinal and blood brain barriers. However, up to now, there are no clear relationships between macromolecular features of polycations (molecular weight, mean charge density, charge repartition, etc.) and their interactions with blood elements (which bear superficial negative charges). The interaction on the red blood cell membrane with synthetic polycations having well-controlled macromolecular features and functionalized with pendent polyethylene glycol segments was investigated. The alterations over stationary and dynamic viscoelastic properties of erythrocyte membranes were analyzed through laser diffractometry. Image digital analysis was used to study erythrocyte agglutination mediated by anti-glycophorin. Results show different reactivities of the polycations on the erythrocyte membrane. These findings could provide more information about the mechanisms of polycation interaction on erythrocyte membranes. We consider that this work could provide useful tools to understand and improve the haemocompatibility of polycations and enlarge their potential in clinic.

  17. Insights into the Antimicrobial Mechanism of Action of Human RNase6: Structural Determinants for Bacterial Cell Agglutination and Membrane Permeation

    PubMed Central

    Pulido, David; Arranz-Trullén, Javier; Prats-Ejarque, Guillem; Velázquez, Diego; Torrent, Marc; Moussaoui, Mohammed; Boix, Ester

    2016-01-01

    Human Ribonuclease 6 is a secreted protein belonging to the ribonuclease A (RNaseA) superfamily, a vertebrate specific family suggested to arise with an ancestral host defense role. Tissue distribution analysis revealed its expression in innate cell types, showing abundance in monocytes and neutrophils. Recent evidence of induction of the protein expression by bacterial infection suggested an antipathogen function in vivo. In our laboratory, the antimicrobial properties of the protein have been evaluated against Gram-negative and Gram-positive species and its mechanism of action was characterized using a membrane model. Interestingly, our results indicate that RNase6, as previously reported for RNase3, is able to specifically agglutinate Gram-negative bacteria as a main trait of its antimicrobial activity. Moreover, a side by side comparative analysis with the RN6(1–45) derived peptide highlights that the antimicrobial activity is mostly retained at the protein N-terminus. Further work by site directed mutagenesis and structural analysis has identified two residues involved in the protein antimicrobial action (Trp1 and Ile13) that are essential for the cell agglutination properties. This is the first structure-functional characterization of RNase6 antimicrobial properties, supporting its contribution to the infection focus clearance. PMID:27089320

  18. Isolation and characterization of mutants with lesions affecting pellicle formation and erythrocyte agglutination by type 1 piliated Escherichia coli.

    PubMed Central

    Harris, S L; Elliott, D A; Blake, M C; Must, L M; Messenger, M; Orndorff, P E

    1990-01-01

    The product of the pilE (also called fimH) gene is a minor component of type 1 pili in Escherichia coli. Mutants that have insertions in the pilE gene are fully piliated but unable to bind to and agglutinate guinea pig erythrocytes, a characteristic of wild-type type 1 piliated E. coli. In this paper we describe the isolation of 48 mutants with point lesions that map to the pilE gene. Such mutants were isolated by using mutT mutagenesis and an enrichment procedure devised to favor the growth of individuals that could form a pellicle in static broth containing alpha-methylmannoside, an inhibitor of erythrocyte binding and pellicle formation. Results indicated that the enrichment favored mutants expressing pilE gene products that were defective in mediating erythrocyte binding. Characterization of 12 of the mutants in greater detail revealed that certain lesions affected pilus number and length. In addition, a mutant that was temperature sensitive for erythrocyte binding was isolated and used to provide evidence that pellicle formation relies on the intercellular interaction of pilE gene products. Our results suggest a molecular explanation for the old and paradoxical observations connecting pellicle formation and erythrocyte agglutination by type 1 piliated E. coli. Images PMID:1977736

  19. Insights into the Antimicrobial Mechanism of Action of Human RNase6: Structural Determinants for Bacterial Cell Agglutination and Membrane Permeation.

    PubMed

    Pulido, David; Arranz-Trullén, Javier; Prats-Ejarque, Guillem; Velázquez, Diego; Torrent, Marc; Moussaoui, Mohammed; Boix, Ester

    2016-01-01

    Human Ribonuclease 6 is a secreted protein belonging to the ribonuclease A (RNaseA) superfamily, a vertebrate specific family suggested to arise with an ancestral host defense role. Tissue distribution analysis revealed its expression in innate cell types, showing abundance in monocytes and neutrophils. Recent evidence of induction of the protein expression by bacterial infection suggested an antipathogen function in vivo. In our laboratory, the antimicrobial properties of the protein have been evaluated against Gram-negative and Gram-positive species and its mechanism of action was characterized using a membrane model. Interestingly, our results indicate that RNase6, as previously reported for RNase3, is able to specifically agglutinate Gram-negative bacteria as a main trait of its antimicrobial activity. Moreover, a side by side comparative analysis with the RN6(1-45) derived peptide highlights that the antimicrobial activity is mostly retained at the protein N-terminus. Further work by site directed mutagenesis and structural analysis has identified two residues involved in the protein antimicrobial action (Trp1 and Ile13) that are essential for the cell agglutination properties. This is the first structure-functional characterization of RNase6 antimicrobial properties, supporting its contribution to the infection focus clearance. PMID:27089320

  20. Retinoic acid amide inhibits JAK/STAT pathway in lung cancer which leads to apoptosis.

    PubMed

    Li, Hong-Xing; Zhao, Wei; Shi, Yan; Li, Ya-Na; Zhang, Lian-Shuang; Zhang, Hong-Qin; Wang, Dong

    2015-11-01

    Small cell lung cancer (SCLC) accounts for 12 to 16% of lung neoplasms and has a high rate of metastasis. The present study demonstrates the antiproliferative effect of retinoic acid amide in vitro and in vivo against human lung cancer cells. The results from MTT assay showed a significant growth inhibition of six tested lung cancer cell lines and inhibition of clonogenic growth at 30 μM. Retinoic acid amide also leads to G2/M-phase cell cycle arrest and apoptosis of lung cancer cells. It caused inhibition of JAK2, STAT3, and STAT5, increased the level of p21WAF1, and decreased cyclin A, cyclin B1, and Bcl-XL expression. Retinoic acid amide exhibited a synergistic effect on antiproliferative effects of methotrexate in lung cancer cells. In lung tumor xenografts, the tumor volume was decreased by 82.4% compared to controls. The retinoic acid amide-treated tumors showed inhibition of JAK2/STAT3 activation and Bcl-XL expression. There was also increase in expression of caspase-3 and caspase-9 in tumors on treatment with retinoic acid amide. Thus, retinoic acid amide exhibits promising antiproliferative effects against human lung cancer cells in vitro and in vivo and enhances the antiproliferative effect of methotrexate. PMID:26044560

  1. nSTAT: open-source neural spike train analysis toolbox for Matlab.

    PubMed

    Cajigas, I; Malik, W Q; Brown, E N

    2012-11-15

    Over the last decade there has been a tremendous advance in the analytical tools available to neuroscientists to understand and model neural function. In particular, the point process - generalized linear model (PP-GLM) framework has been applied successfully to problems ranging from neuro-endocrine physiology to neural decoding. However, the lack of freely distributed software implementations of published PP-GLM algorithms together with problem-specific modifications required for their use, limit wide application of these techniques. In an effort to make existing PP-GLM methods more accessible to the neuroscience community, we have developed nSTAT--an open source neural spike train analysis toolbox for Matlab®. By adopting an object-oriented programming (OOP) approach, nSTAT allows users to easily manipulate data by performing operations on objects that have an intuitive connection to the experiment (spike trains, covariates, etc.), rather than by dealing with data in vector/matrix form. The algorithms implemented within nSTAT address a number of common problems including computation of peri-stimulus time histograms, quantification of the temporal response properties of neurons, and characterization of neural plasticity within and across trials. nSTAT provides a starting point for exploratory data analysis, allows for simple and systematic building and testing of point process models, and for decoding of stimulus variables based on point process models of neural function. By providing an open-source toolbox, we hope to establish a platform that can be easily used, modified, and extended by the scientific community to address limitations of current techniques and to extend available techniques to more complex problems. PMID:22981419

  2. Leptin-Induced JAK/STAT Signaling and Cancer Growth.

    PubMed

    Mullen, McKay; Gonzalez-Perez, Ruben Rene

    2016-01-01

    Growth factor and cytokine signaling can influence the development of several cancer types. One of the key players in the development of cancer is the Janus kinas (JAK) signal transducer of activators of transcription (STAT) signaling pathway. The majority of growth factors and cytokine interactions with their membrane-bound receptors trigger JAK-STAT activation. The influential relationship between obesity and cancer is a fact. However, there is a complex sequence of events contributing to the regulation of this mechanism to promote tumor growth, yet to be fully elucidated. The JAK-STAT pathway is influenced by obesity-associated changes that have been shown to impact cancer growth and progression. This intricate process is highly regulated by a vast array of adipokines and cytokines that exert their pleiotropic effects on cancer cells to enhance metastasis to distant target sites. Leptin is a cytokine, or more precise, an adipokine secreted mainly by adipose tissue that requires JAK-STAT activation to exert its biological functions. Leptin is the central regulator of energy balance and appetite. Leptin binding to its receptor OB-R in turn activates JAK-STAT, which induces proliferation, angiogenesis, and anti-apoptotic events in normal cells and malignant cells expressing the receptor. Leptin also induces crosstalk with Notch and IL-1 (NILCO), which involves other angiogenic factors promoting tumor growth. Therefore, the existence of multiple novel classes of therapeutics that target the JAK/STAT pathway has significant clinical implications. Then, the identification of the signaling networks and factors that regulate the obesity-cancer link to which potential pharmacologic interventions can be implemented to inhibit tumor growth and metastasis. In this review, we will discuss the specific relationship between leptin-JAK-STAT signaling and cancer. PMID:27472371

  3. Activation of oligodendroglial Stat3 is required for efficient remyelination

    PubMed Central

    Steelman, Andrew J.; Zhou, Yun; Koit, Hisami; Kim, SunJa; Payne, H. Ross; Lu, Q. Richard; Li, Jianrong

    2016-01-01

    Multiple sclerosis is the most prevalent demyelinating disease of the central nervous system (CNS) and is histologically characterized by perivascular demyelination as well as neurodegeneration. While the degree of axonal damage is correlated with clinical disability, it is believed that remyelination can protect axons from degeneration and slow disease progression. Therefore, understanding the intricacies associated with myelination and remyelination may lead to therapeutics that can enhance the remyelination process and slow axon degeneration and loss of function. Ciliary neurotrophic factor (CNTF) family cytokines such as leukemia inhibitory factor (LIF) and interleukin11(IL-11) are known to promote oligodendrocyte maturation and remyelination in experimental models of demyelination. Because CNTF family member binding to the gp 130 receptor results in activation of the JAK2/Stat3 pathway we investigated the necessity of oligodendroglial Stat3 in transducing the signal required for myelination and remyelination. We found that Stat3 activation in the CNS coincides with myelination during development. Stimulation of oligodendrocyte precursor cells (OPCs) with CNTF or LIF promoted OPC survival and final differentiation, which was completely abolished by pharmacologic blockade of Stat3 activation with JAK2 inhibitor. Similarly, genetic ablation of Stat3 in oligodendrocyte lineage cells prevented CNTF-induced OPC differentiation in culture. In vivo, while oligodendroglial Stat3 signaling appears to be dispensable for developmental CNS myelination, it is required for oligodendrocyte regeneration and efficient remyelination after toxin-induced focal demyelination in the adult brain. Our data suggest a critical function for oligodendroglial Stat3 signaling in myelin repair. PMID:27060559

  4. Activation of oligodendroglial Stat3 is required for efficient remyelination.

    PubMed

    Steelman, Andrew J; Zhou, Yun; Koito, Hisami; Kim, SunJa; Payne, H Ross; Lu, Q Richard; Li, Jianrong

    2016-07-01

    Multiple sclerosis is the most prevalent demyelinating disease of the central nervous system (CNS) and is histologically characterized by perivascular demyelination as well as neurodegeneration. While the degree of axonal damage is correlated with clinical disability, it is believed that remyelination can protect axons from degeneration and slow disease progression. Therefore, understanding the intricacies associated with myelination and remyelination may lead to therapeutics that can enhance the remyelination process and slow axon degeneration and loss of function. Ciliary neurotrophic factor (CNTF) family cytokines such as leukemia inhibitory factor (LIF) and interleukin 11 (IL-11) are known to promote oligodendrocyte maturation and remyelination in experimental models of demyelination. Because CNTF family member binding to the gp130 receptor results in activation of the JAK2/Stat3 pathway we investigated the necessity of oligodendroglial Stat3 in transducing the signal required for myelination and remyelination. We found that Stat3 activation in the CNS coincides with myelination during development. Stimulation of oligodendrocyte precursor cells (OPCs) with CNTF or LIF promoted OPC survival and final differentiation, which was completely abolished by pharmacologic blockade of Stat3 activation with JAK2 inhibitor. Similarly, genetic ablation of Stat3 in oligodendrocyte lineage cells prevented CNTF-induced OPC differentiation in culture. In vivo, while oligodendroglial Stat3 signaling appears to be dispensable for developmental CNS myelination, it is required for oligodendrocyte regeneration and efficient remyelination after toxin-induced focal demyelination in the adult brain. Our data suggest a critical function for oligodendroglial Stat3 signaling in myelin repair. PMID:27060559

  5. Rac1 promotes chondrogenesis by regulating STAT3 signaling pathway.

    PubMed

    Kim, Hyoin; Sonn, Jong Kyung

    2016-09-01

    The small GTPase protein Rac1 is involved in a wide range of biological processes including cell differentiation. Previously, Rac1 was shown to promote chondrogenesis in micromass cultures of limb mesenchyme. However, the pathways mediating Rac1's role in chondrogenesis are not fully understood. This study aimed to explore the molecular mechanisms by which Rac1 regulates chondrogenic differentiation. Phosphorylation of signal transducer and activator of transcription 3 (STAT3) was increased as chondrogenesis proceeded in micromass cultures of chick wing bud mesenchyme. Inhibition of Rac1 with NSC23766, janus kinase 2 (JAK2) with AG490, or STAT3 with stattic inhibited chondrogenesis and reduced phosphorylation of STAT3. Conversely, overexpression of constitutively active Rac1 (Rac L61) increased phosphorylation of STAT3. Rac L61 expression resulted in increased expression of interleukin 6 (IL-6), and treatment with IL-6 increased phosphorylation of STAT3. NSC23766, AG490, and stattic prohibited cell aggregation, whereas expression of Rac L61 increased cell aggregation, which was reduced by stattic treatment. Our studies indicate that Rac1 induces STAT3 activation through expression and action of IL-6. Overexpression of Rac L61 increased expression of bone morphogenic protein 4 (BMP4). BMP4 promoted chondrogenesis, which was inhibited by K02288, an activin receptor-like kinase-2 inhibitor, and increased phosphorylation of p38 MAP kinase. Overexpression of Rac L61 also increased phosphorylation of p38 MAPK, which was reduced by K02288. These results suggest that Rac1 activates STAT3 by expression of IL-6, which in turn increases expression and activity of BMP4, leading to the promotion of chondrogenesis. PMID:27306109

  6. JAK Kinase Inhibition Abrogates STAT3 Activation and Head and Neck Squamous Cell Carcinoma Tumor Growth12

    PubMed Central

    Sen, Malabika; Pollock, Netanya I.; Black, John; DeGrave, Kara A.; Wheeler, Sarah; Freilino, Maria L.; Joyce, Sonali; Lui, Vivian W.Y.; Zeng, Yan; Chiosea, Simion I.; Grandis, Jennifer R.

    2015-01-01

    Aberrant activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) 3 has been implicated in cell proliferation and survival of many cancers including head and neck squamous cell carcinoma (HNSCC). AZD1480, an orally active pharmacologic inhibitor of JAK1/JAK2, has been tested in several cancer models. In the present study, the in vitro and in vivo effects of AZD1480 were evaluated in HNSCC preclinical models to test the potential use of JAK kinase inhibition for HNSCC therapy. AZD1480 treatment decreased HNSCC proliferation in HNSCC cell lines with half maximal effective concentration (EC50) values ranging from 0.9 to 4 μM in conjunction with reduction of pSTAT3Tyr705 expression. In vivo antitumor efficacy of AZD1480 was demonstrated in patient-derived xenograft (PDX) models derived from two independent HNSCC tumors. Oral administration of AZD1480 reduced tumor growth in conjunction with decreased pSTAT3Tyr705 expression that was observed in both PDX models. These findings suggest that the JAK1/2 inhibitors abrogate STAT3 signaling and may be effective in HNSCC treatment approaches. PMID:25810010

  7. Validation of the i-STAT system for the analysis of blood gases and acid-base status in juvenile sandbar shark (Carcharhinus plumbeus).

    PubMed

    Harter, T S; Morrison, P R; Mandelman, J W; Rummer, J L; Farrell, A P; Brill, R W; Brauner, C J

    2015-01-01

    Accurate measurements of blood gases and acid-base status require an array of sophisticated laboratory equipment that is typically not available during field research; such is the case for many studies on the stress physiology, ecology and conservation of elasmobranch fish species. Consequently, researchers have adopted portable clinical analysers that were developed for the analysis of human blood characteristics, but often without thoroughly validating these systems for their use on fish. The aim of our study was to test the suitability of the i-STAT system, the most commonly used portable clinical analyser in studies on fish, for analysing blood gases and acid-base status in elasmobranchs, over a broad range of conditions and using the sandbar shark (Carcharhinus plumbeus) as a model organism. Our results indicate that the i-STAT system can generate useful measurements of whole blood pH, and the use of appropriate correction factors may increase the accuracy of results. The i-STAT system was, however, unable to generate reliable results for measurements of partial pressure of oxygen (PO2) and the derived parameter of haemoglobin O2 saturation. This is probably due to the effect of a closed-system temperature change on PO2 within the i-STAT cartridge and the fact that the temperature correction algorithms used by i-STAT assume a human temperature dependency of haemoglobin-O2 binding; in many ectotherms, this assumption will lead to equivocal i-STAT PO2 results. The in vivo partial pressure of CO2 (PCO2) in resting sandbar sharks is probably below the detection limit for PCO2 in the i-STAT system, and the measurement of higher PCO2 tensions was associated with a large measurement error. In agreement with previous work, our results indicate that the i-STAT system can generate useful data on whole blood pH in fishes, but not blood gases. PMID:27293687

  8. Validation of the i-STAT system for the analysis of blood gases and acid–base status in juvenile sandbar shark (Carcharhinus plumbeus)

    PubMed Central

    Harter, T. S.; Morrison, P. R.; Mandelman, J. W.; Rummer, J. L.; Farrell, A. P.; Brill, R. W.; Brauner, C. J.

    2015-01-01

    Accurate measurements of blood gases and acid–base status require an array of sophisticated laboratory equipment that is typically not available during field research; such is the case for many studies on the stress physiology, ecology and conservation of elasmobranch fish species. Consequently, researchers have adopted portable clinical analysers that were developed for the analysis of human blood characteristics, but often without thoroughly validating these systems for their use on fish. The aim of our study was to test the suitability of the i-STAT system, the most commonly used portable clinical analyser in studies on fish, for analysing blood gases and acid–base status in elasmobranchs, over a broad range of conditions and using the sandbar shark (Carcharhinus plumbeus) as a model organism. Our results indicate that the i-STAT system can generate useful measurements of whole blood pH, and the use of appropriate correction factors may increase the accuracy of results. The i-STAT system was, however, unable to generate reliable results for measurements of partial pressure of oxygen (PO2) and the derived parameter of haemoglobin O2 saturation. This is probably due to the effect of a closed-system temperature change on PO2 within the i-STAT cartridge and the fact that the temperature correction algorithms used by i-STAT assume a human temperature dependency of haemoglobin–O2 binding; in many ectotherms, this assumption will lead to equivocal i-STAT PO2 results. The in vivo partial pressure of CO2 (PCO2) in resting sandbar sharks is probably below the detection limit for PCO2 in the i-STAT system, and the measurement of higher PCO2 tensions was associated with a large measurement error. In agreement with previous work, our results indicate that the i-STAT system can generate useful data on whole blood pH in fishes, but not blood gases. PMID:27293687

  9. Human Cytomegalovirus IE1 Protein Disrupts Interleukin-6 Signaling by Sequestering STAT3 in the Nucleus

    PubMed Central

    Reitsma, Justin M.; Sato, Hiromi; Nevels, Michael

    2013-01-01

    In the canonical STAT3 signaling pathway, binding of agonist to receptors activates Janus kinases that phosphorylate cytoplasmic STAT3 at tyrosine 705 (Y705). Phosphorylated STAT3 dimers accumulate in the nucleus and drive the expression of genes involved in inflammation, angiogenesis, invasion, and proliferation. Here, we demonstrate that human cytomegalovirus (HCMV) infection rapidly promotes nuclear localization of STAT3 in the absence of robust phosphorylation at Y705. Furthermore, infection disrupts interleukin-6 (IL-6)-induced phosphorylation of STAT3 and expression of a subset of IL-6-induced STAT3-regulated genes, including SOCS3. We show that the HCMV 72-kDa immediate-early 1 (IE1) protein associates with STAT3 and is necessary to localize STAT3 to the nucleus during infection. Furthermore, expression of IE1 is sufficient to disrupt IL-6-induced phosphorylation of STAT3, binding of STAT3 to the SOCS3 promoter, and SOCS3 gene expression. Finally, inhibition of STAT3 nuclear localization or STAT3 expression during infection is linked to diminished HCMV genome replication. Viral gene expression is also disrupted, with the greatest impact seen following viral DNA synthesis. Our study identifies IE1 as a new regulator of STAT3 intracellular localization and IL-6 signaling and points to an unanticipated role of STAT3 in HCMV infection. PMID:23903834

  10. Structural Tailoring of Advanced Turboprops (STAT). Theoretical manual

    NASA Technical Reports Server (NTRS)

    Brown, K. W.

    1992-01-01

    This manual describes the theories in the Structural Tailoring of Advanced Turboprops (STAT) computer program, which was developed to perform numerical optimizations on highly swept propfan blades. The optimization procedure seeks to minimize an objective function, defined as either direct operating cost or aeroelastic differences between a blade and its scaled model, by tuning internal and external geometry variables that must satisfy realistic blade design constraints. The STAT analyses include an aerodynamic efficiency evaluation, a finite element stress and vibration analysis, an acoustic analysis, a flutter analysis, and a once-per-revolution (1-p) forced response life prediction capability. The STAT constraints include blade stresses, blade resonances, flutter, tip displacements, and a 1-P forced response life fraction. The STAT variables include all blade internal and external geometry parameters needed to define a composite material blade. The STAT objective function is dependent upon a blade baseline definition which the user supplies to describe a current blade design for cost optimization or for the tailoring of an aeroelastic scale model.

  11. Components of Spatial Thinking: Evidence from a Spatial Thinking Ability Test

    ERIC Educational Resources Information Center

    Lee, Jongwon; Bednarz, Robert

    2012-01-01

    This article introduces the development and validation of the spatial thinking ability test (STAT). The STAT consists of sixteen multiple-choice questions of eight types. The STAT was validated by administering it to a sample of 532 junior high, high school, and university students. Factor analysis using principal components extraction was applied…

  12. Mechanisms of Jak/STAT signaling in immunity and disease

    PubMed Central

    Villarino, Alejandro V.; Kanno, Yuka; O’Shea, John J.

    2015-01-01

    More than 2 decades ago, experiments on the antiviral mechanisms of interferons led to the discovery of Janus kinases (JAK) and their downstream effectors, the signal transducer of activation (STAT) proteins. This pathway has since become a paradigm for membrane to nucleus signaling and has come to explain how a broad range of soluble factors, including cytokines and hormones, mediate their diverse functions. Jak/STAT research has not only impacted basic science, particularly in the context of intercellular communication and cell-extrinsic control of gene expression, but has also become a prototype for transition from bench to bedside, culminating in the development and clinical implementation of pathway-specific therapeutics. This brief review will synthesize current understanding of Jak/STAT biology while taking stock of the lessons learned and the challenges that lie ahead. PMID:25527793

  13. Mycoplasma pneumoniae Modulates STAT3-STAT6/EGFR-FOXA2 Signaling To Induce Overexpression of Airway Mucins

    PubMed Central

    Hao, Yonghua; Kuang, Zhizhou; Jing, Jia; Miao, Jinfeng; Mei, Li Yu; Lee, Ryan J.; Kim, Susie; Choe, Shawn; Krause, Duncan C.

    2014-01-01

    Aberrant mucin secretion and accumulation in the airway lumen are clinical hallmarks associated with various lung diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. Mycoplasma pneumoniae, long appreciated as one of the triggers of acute exacerbations of chronic pulmonary diseases, has recently been reported to promote excessive mucus secretion. However, the mechanism of mucin overproduction induced by M. pneumoniae remains unclear. This study aimed to determine the mechanism by which M. pneumoniae induces mucus hypersecretion by using M. pneumoniae infection of mouse lungs, human primary bronchial epithelial (NHBE) cells cultured at the air-liquid interface, and the conventionally cultured airway epithelial NCI-H292 cell line. We demonstrated that M. pneumoniae induced the expression of mucins MUC5AC and MUC5B by activating the STAT6-STAT3 and epidermal growth factor receptor (EGFR) signal pathways, which in turn downregulated FOXA2, a transcriptional repressor of mucin biosynthesis. The upstream stimuli of these pathways, including interleukin-4 (IL-4), IL-6, and IL-13, increased dramatically upon exposure to M. pneumoniae. Inhibition of the STAT6, STAT3, and EGFR signaling pathways significantly restored the expression of FOXA2 and attenuated the expression of airway mucins MUC5AC and MUC5B. Collectively, these studies demonstrated that M. pneumoniae induces airway mucus hypersecretion by modulating the STAT/EGFR-FOXA2 signaling pathways. PMID:25287927

  14. Evaluation of STAT medication ordering process in a community hospital

    PubMed Central

    Walsh., Kim; Schwartz., Barbara

    Background: In most health care facilities, problems related to delays in STAT medication order processing time are of common concern. Objective: The purpose of this study was to evaluate processing time for STAT orders at Kimball Medical Center. Methods: All STAT orders were reviewed to determine processing time; order processing time was also stratified by physician order entry (physician entered (PE) orders vs. non-physician entered (NPE) orders). Collected data included medication ordered, indication, time ordered, time verified by pharmacist, time sent from pharmacy, and time charted as given to the patient. Results: A total of 502 STAT orders were reviewed and 389 orders were included for analysis. Overall, median time was 29 minutes, IQR 16–63; p<0.0001.). The time needed to process NPE orders was significantly less than that needed for PE orders (median 27 vs. 34 minutes; p=0.026). In terms of NPE orders, the median total time required to process STAT orders for medications available in the Automated Dispensing Devices (ADM) was within 30 minutes, while that required to process orders for medications not available in the ADM was significantly greater than 30 minutes. For PE orders, the median total time required to process orders for medications available in the ADM (i.e., not requiring pharmacy involvement) was significantly greater than 30 minutes. [Median time = 34 minutes (p<0.001)]. Conclusion: We conclude that STAT order processing time may be improved by increasing the availability of medications in ADM, and pharmacy involvement in the verification process. PMID:27382418

  15. Ethanolamine is a novel STAT-3 dependent cardioprotective agent.

    PubMed

    Kelly, Roisin F; Lamont, Kim T; Somers, Sarin; Hacking, Damian; Lacerda, Lydia; Thomas, Paul; Opie, Lionel H; Lecour, Sandrine

    2010-11-01

    Ethanolamine is a biogenic amine found naturally in the body as part of membrane lipids and as a metabolite of the cardioprotective substances, sphingosine-1-phosphate (S1P) and anandamide. In the brain, ethanolamine, formed from the breakdown of anandamide protects against ischaemic apoptosis. However, the effects of ethanolamine in the heart are unknown. Signal transducer and activator of transcription 3 (STAT-3) is a critical prosurvival factor in ischaemia/reperfusion (I/R) injury. Therefore, we investigated whether ethanolamine protects the heart via activation of STAT-3. Isolated hearts from wildtype or cardiomyocyte specific STAT-3 knockout (K/O) mice were pre-treated with ethanolamine (Etn) (0.3 mmol/L) before I/R insult. In vivo rat hearts were subjected to 30 min ischaemia/2 h reperfusion in the presence or absence of 5 mg/kg S1P and/or the FAAH inhibitor, URB597. Infarct size was measured at the end of each protocol by triphenyltetrazolium chloride staining. Pre-treatment with ethanolamine decreased infarct size in isolated mouse or rat hearts subjected to I/R but this infarct sparing effect was lost in cardiomyocyte specific STAT-3 deficient mice. Pre-treatment with ethanolamine increased nuclear phosphorylated STAT-3 [control 0.75 ± 0.08 vs. Etn 1.50 ± 0.09 arbitrary units; P < 0.05]. Our findings suggest a novel cardioprotective role for ethanolamine against I/R injury via activation of STAT-3. PMID:20938668

  16. Bcl6 promotes osteoblastogenesis through Stat1 inhibition

    SciTech Connect

    Fujie, Atsuhiro; Funayama, Atsushi; Miyauchi, Yoshiteru; Sato, Yuiko; Kobayashi, Tami; Kanagawa, Hiroya; Katsuyama, Eri; Hao, Wu; Tando, Toshimi; Watanabe, Ryuichi; Morita, Mayu; Miyamoto, Kana; Kanaji, Arihiko; Morioka, Hideo; Matsumoto, Morio; Toyama, Yoshiaki; Miyamoto, Takeshi

    2015-02-13

    Bone mass is tightly controlled by a balance between osteoclast and osteoblast activities. Although these cell types mature via different pathways, some factors reportedly regulate differentiation of both. Here, in a search for factors governing osteoblastogenesis but also expressed in osteoclasts to control both cell types by one molecule, we identified B cell lymphoma 6 (Bcl6) as one of those factors and show that it promotes osteoblast differentiation. Bcl6 was previously shown to negatively regulate osteoclastogenesis. We report that lack of Bcl6 results in significant inhibition of osteoblastogensis in vivo and in vitro and in defects in secondary ossification center formation in vivo. Signal transducer and activator of transcription 1 (Stat1) reportedly attenuates osteoblast differentiation by inhibiting nuclear translocation of runt-related transcription factor 2 (Runx2), which is essential for osteoblast differentiation. We found that lack of Bcl6 resulted in significant elevation of Stat1 mRNA and protein expression in osteoblasts and showed that Stat1 is a direct target of Bcl6 using a chromatin immune-precipitation assay. Mice lacking both Bcl6 and Stat1 (DKO) exhibited significant rescue of bone mass and osteoblastic parameters as well as partial rescue of secondary ossification center formation compared with Bcl6-deficient mice in vivo. Altered osteoblastogenesis in Bcl6-deficient cells was also restored in DKO in vitro. Thus, Bcl6 plays crucial roles in regulating both osteoblast activation and osteoclast inhibition. - Highlights: • Bcl6 is required for osteoblast differentiation. • Bcl6{sup −/−} mice exhibited altered osteoblastogenesis and reduced bone mass in vivo and in vitro. • We identified Stat1 as a direct target of Bcl6 in osteoblasts. • Bcl6 and Stat1 doubly deficient mice exhibited rescued bone phenotypes compared with Bcl6{sup −/−} mice.

  17. NCO-sP(EO-stat-PO) Coatings on Gold Sensors—a QCM Study of Hemocompatibility

    PubMed Central

    Sinn, Stefan; Eichler, Mirjam; Müller, Lothar; Bünger, Daniel; Groll, Jürgen; Ziemer, Gerhard; Rupp, Frank; Northoff, Hinnak; Geis-Gerstorfer, Jürgen; Gehring, Frank K.; Wendel, Hans P.

    2011-01-01

    The reliability of implantable blood sensors is often hampered by unspecific adsorption of plasma proteins and blood cells. This not only leads to a loss of sensor signal over time, but can also result in undesired host vs. graft reactions. Within this study we evaluated the hemocompatibility of isocyanate conjugated star shaped polytheylene oxide—polypropylene oxide co-polymers NCO-sP(EO-stat-PO) when applied to gold surfaces as an auspicious coating material for gold sputtered blood contacting sensors. Quartz crystal microbalance (QCM) sensors were coated with ultrathin NCO-sP(EO-stat-PO) films and compared with uncoated gold sensors. Protein resistance was assessed by QCM measurements with fibrinogen solution and platelet poor plasma (PPP), followed by quantification of fibrinogen adsorption. Hemocompatibility was tested by incubation with human platelet rich plasma (PRP). Thrombin antithrombin-III complex (TAT), β-thromboglobulin (β-TG) and platelet factor 4 (PF4) were used as coagulation activation markers. Furthermore, scanning electron microscopy (SEM) was used to visualize platelet adhesion to the sensor surfaces. Compared to uncoated gold sensors, NCO-sP(EO-stat-PO) coated sensors revealed significant better resistance against protein adsorption, lower TAT generation and a lower amount of adherent platelets. Moreover, coating with ultrathin NCO-sP(EO-stat-PO) films creates a cell resistant hemocompatible surface on gold that increases the chance of prolonged sensor functionality and can easily be modified with specific receptor molecules. PMID:22163899

  18. Genome-wide discovery of functional transcription factor binding sites by comparative genomics: The case of Stat3

    PubMed Central

    Vallania, Francesco; Schiavone, Davide; Dewilde, Sarah; Pupo, Emanuela; Garbay, Serge; Calogero, Raffaele; Pontoglio, Marco; Provero, Paolo; Poli, Valeria

    2009-01-01

    The identification of direct targets of transcription factors is a key problem in the study of gene regulatory networks. However, the use of high throughput experimental methods, such as ChIP-chip and ChIP-sequencing, is limited by their high cost and strong dependence on cellular type and context. We developed a computational method for the genome-wide identification of functional transcription factor binding sites based on positional weight matrices, comparative genomics, and gene expression profiling. The method was applied to Stat3, a transcription factor playing crucial roles in inflammation, immunity and oncogenesis, and able to induce distinct subsets of target genes in different cell types or conditions. A newly generated positional weight matrix enabled us to assign affinity scores of high specificity, as measured by EMSA competition assays. Phylogenetic conservation with 7 vertebrate species was used to select the binding sites most likely to be functional. Validation was carried out on predicted sites within genes identified as differentially expressed in the presence or absence of Stat3 by microarray analysis. Twelve of the fourteen sites tested were bound by Stat3 in vivo, as assessed by Chromatin Immunoprecipitation, allowing us to identify 9 Stat3 transcriptional targets. Given its high validation rate, and the availability of large transcription factor-dependent gene expression datasets obtained under diverse experimental conditions, our approach appears to be a valid alternative to high-throughput experimental assays for the discovery of novel direct targets of transcription factors. PMID:19282476

  19. TLR agonist–Stat3 siRNA conjugates: cell-specific gene silencing and enhanced antitumor immune responses

    PubMed Central

    Kortylewski, Marcin; Swiderski, Piotr; Herrmann, Andreas; Wang, Lin; Kowolik, Claudia; Kujawski, Maciej; Lee, Heehyoung; Scuto, Anna; Liu, Yong; Yang, Chunmei; Deng, Jiehui; Soifer, Harris S.; Raubitschek, Andrew; Forman, Stephen; Rossi, John J.; Pardoll, Drew M.; Jove, Richard; Yu, Hua

    2010-01-01

    Efficient delivery of siRNA to specific cell populations in vivo remains a formidable challenge to its successful therapeutic application. We describe a novel siRNA-based approach – synthetically linking siRNA to an oligonucleotide TLR9 agonist – that targets and silences genes in TLR9+ myeloid cells and B cells, both of which are key components of the tumor microenvironment. Because Stat3 in tumor-associated immune cells suppresses antitumor immune responses and hinders TLR9-induced immune stimulation, we tested CpG-Stat3siRNA conjugates for anti-tumor effects. When injected locally at the tumor site or systemically through an intravenous route, the CpG-Stat3siRNA conjugates access tumor-associated dendritic cells, macrophages and B cells, inhibit Stat3 expression, leading to activation of tumor-associated immune cells, and ultimately potent anti-tumor immune responses. Our findings demonstrate the potential of TLR agonist-siRNA conjugates for targeted gene silencing coupled with TLR stimulation and immune activation in the tumor microenvironment. PMID:19749770

  20. Topical application of a vitamin D analogue exacerbates atopic dermatitis and induces the atopic dermatitis-like phenotype in Stat6VT mice.

    PubMed

    Turner, Matthew J; Dasilva-Arnold, Sonia C; Yi, Qiaofang; Mehrotra, Purvi; Kaplan, Mark H; Travers, Jeffrey B

    2013-01-01

    Calcipotriene is a topical vitamin D3 analogue approved for the treatment of plaque and scalp psoriasis. We report the case of a 2-year-old boy whose atopic dermatitis (AD) flared in response to application of calcipotriene 0.005% cream and solution for a mistaken diagnosis of plaque and scalp psoriasis. We investigated whether the patient's eruption was secondary to an allergic contact dermatitis. In the Stat6VT mouse model of AD we tested whether calcipotriene could induce the otherwise-spontaneous AD-like phenotype. Closed patch testing was done on the patient with calcipotriene solution and cream, moisturizing cream, and 51% isopropanol. Stat6VT and wild-type (WT) mice were treated for 7 days with calcipotriene solution or vehicle (isopropanol) applied to the right and left upper back skin, respectively, after which mice were followed longitudinally for 10 weeks. Biopsy specimens from prior treatment sites were then collected for histology and RNA isolation. RNA was analyzed for interleukin (IL-4) expression using quantitative polymerase chain reaction. Patch testing was negative. Stat6VT mice, in contrast to WT mice, developed a persistent eczematous dermatitis at sites of calcipotriene application. Clinical and histologic features and high IL-4 transcript levels were consistent with the spontaneous AD-like phenotype seen in Stat6VT mice. At sites of active disease, calcipotriene can worsen a flare of AD. In Stat6VT mice, calcipotriene can induce the AD-like phenotype. PMID:23889122

  1. Distribution of the mammalian Stat gene family in mouse chromosomes

    SciTech Connect

    Copeland, N.G.; Gilbert, D.J.; Jenkins, N.A.

    1995-09-01

    Studies of transcriptional activation by interferons and a variety of cytokines have led to the identification of a family of proteins that serve as signal transducers and activators of transcription, Stats. Here, we report that the seven mouse Stat loci map in three clusters, with each cluster located on a different mouse autosome. The data suggest that the family has arisen via a tandem duplication of the ancestral locus, followed by dispersion of the linked loci to different mouse chromosomes. 28 refs., 1 fig., 1 tab.

  2. K/Ar dating of lunar soils. IV - Orange glass from 74220 and agglutinates from 14259 and 14163

    NASA Technical Reports Server (NTRS)

    Alexander, E. C., Jr.; Coscio, M. R., Jr.; Dragon, J. C.; Saito, K.

    1980-01-01

    Total fusion Ar-40 - A-39 analyses of orange glass from lunar soil 74220 combined with the sums of earlier stepwise heating data by other workers have yielded a precise K/Ar isochron with a slope corresponding to an age of 3.66 + or - 0.03 G.y. for the orange glass. The result is in marginal agreement with Huneke's (1978) age of 3.60 + or - 0.04 G.y. for 74220 glass. The Ar systematics in the agglutinates from 14259 and 14163 are dominated by volume correlated argon. Step-wise heating analyses yield data which define experimentally reproducible linear arrays in Ar-40/Ar-36 vs. K-40/Ar-36 diagrams. The slopes of these arrays correspond formally to very old ages, but it is not clear, however, that such ages have any physical significance.

  3. Novel sorafenib analogues induce apoptosis through SHP-1 dependent STAT3 inactivation in human breast cancer cells

    PubMed Central

    2013-01-01

    Introduction Signal transducers and activators of transcription 3 (STAT3) signaling is constitutively activated in various cancers including breast cancer and has emerged as a novel potential anti-cancer target. STAT3 has been demonstrated to be a target of sorafenib, and a protein tyrosine phosphatase Src homology 2-domain containing tyrosine phosphatase 1 (SHP-1) has been demonstrated to downregulate p-STAT3 via its phosphatase activity. Here, we tested the efficacy of two sorafenib analogues, SC-1 and SC-43, in breast cancer cells and examined the drug mechanism. Methods Breast cancer cell lines were used for in vitro studies. Cell viability was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was examined by flow cytometry and western blot. Signal transduction pathways in cells were assessed by western blot. In vivo efficacy of sorafenib, SC-1 and SC-43 was tested in xenografted nude mice. Results SC-1 and SC-43 induced more potent apoptosis than sorafenib, in association with downregulation of p-STAT3 and its downstream proteins cyclin D1 and survivin in a dose-dependent manner in breast cancer cell lines (HCC-1937, MDA-MB-468, MDA-MB-231, MDA-MB-453, SK-BR3, MCF-7). Overexpression of STAT3 in MDA-MB-468 cells protected the cells from apoptosis induced by sorafenib, SC-1 and SC-43. Moreover, SC-1 and SC-43 upregulated SHP-1 activity to a greater extent than sorafenib as measured by in vitro phosphatase assays. Knockdown of SHP-1 by siRNA reduced apoptosis induced by SC-1 and SC-43. Importantly, SC-1 and SC-43 showed more efficacious antitumor activity and p-STAT3 downregulation than sorafenib in MDA-MB-468 xenograft tumors. Conclusions Novel sorafenib analogues SC-1 and SC-43 induce apoptosis through SHP-1 dependent STAT3 inactivation and demonstrate greater potency than sorafenib in human breast cancer cells. PMID:23938089

  4. STAT1β Is Not Dominant Negative and Is Capable of Contributing to Gamma Interferon-Dependent Innate Immunity

    PubMed Central

    Semper, Christian; Leitner, Nicole R.; Lassnig, Caroline; Parrini, Matthias; Mahlakõiv, Tanel; Rammerstorfer, Michael; Lorenz, Karin; Rigler, Doris; Müller, Simone; Kolbe, Thomas; Vogl, Claus; Rülicke, Thomas; Staeheli, Peter; Decker, Thomas; Müller, Mathias

    2014-01-01

    The transcription factor STAT1 is essential for interferon (IFN)-mediated immunity in humans and mice. STAT1 function is tightly regulated, and both loss- and gain-of-function mutations result in severe immune diseases. The two alternatively spliced isoforms, STAT1α and STAT1β, differ with regard to a C-terminal transactivation domain, which is absent in STAT1β. STAT1β is considered to be transcriptionally inactive and to be a competitive inhibitor of STAT1α. To investigate the functions of the STAT1 isoforms in vivo, we generated mice deficient for either STAT1α or STAT1β. As expected, the functions of STAT1α and STAT1β in IFN-α/β- and IFN-λ-dependent antiviral activity are largely redundant. In contrast to the current dogma, however, we found that STAT1β is transcriptionally active in response to IFN-γ. In the absence of STAT1α, STAT1β shows more prolonged IFN-γ-induced phosphorylation and promoter binding. Both isoforms mediate protective, IFN-γ-dependent immunity against the bacterium Listeria monocytogenes, although with remarkably different efficiencies. Our data shed new light on the potential contributions of the individual STAT1 isoforms to STAT1-dependent immune responses. Knowledge of STAT1β's function will help fine-tune diagnostic approaches and help design more specific strategies to interfere with STAT1 activity. PMID:24710278

  5. Inducible, Dose-Adjustable and Time-Restricted Reconstitution of Stat1 Deficiency In Vivo

    PubMed Central

    Leitner, Nicole R.; Lassnig, Caroline; Rom, Rita; Heider, Susanne; Bago-Horvath, Zsuzsanna; Eferl, Robert; Müller, Simone; Kolbe, Thomas; Kenner, Lukas; Rülicke, Thomas; Strobl, Birgit; Müller, Mathias

    2014-01-01

    Signal transducer and activator of transcription (STAT) 1 is a key player in interferon (IFN) signaling, essential in mediating host defense against viruses and other pathogens. STAT1 levels are tightly regulated and loss- or gain-of-function mutations in mice and men lead to severe diseases. We have generated a doxycycline (dox) -inducible, FLAG-tagged Stat1 expression system in mice lacking endogenous STAT1 (i.e. Stat1ind mice). We show that STAT1 expression depends on the time and dose of dox treatment in primary cells and a variety of organs isolated from Stat1ind mice. In bone marrow-derived macrophages, a fraction of the amount of STAT1 present in WT cells is sufficient for full expression of IFN-induced genes. Dox-induced STAT1 established protection against virus infections in primary cells and mice. The availability of the Stat1ind mouse model will enable an examination of the consequences of variable amounts of STAT1. The model will also permit the study of STAT1 dose-dependent and reversible functions as well as of STAT1's contributions to the development, progression and resolution of disease. PMID:24489749

  6. Antibiotic-Driven Dysbiosis Mediates Intraluminal Agglutination and Alternative Segregation of Enterococcus faecium from the Intestinal Epithelium

    PubMed Central

    Top, Janetta; Bayjanov, Jumamurat R.; Kemperman, Hans; Rogers, Malbert R. C.; Paganelli, Fernanda L.; Bonten, Marc J. M.; Willems, Rob J. L.

    2015-01-01

    ABSTRACT The microbiota of the mammalian gastrointestinal tract is a complex ecosystem of bacterial communities that continuously interact with the mucosal immune system. In a healthy host, the mucosal immune system maintains homeostasis in the intestine and prevents invasion of pathogenic bacteria, a phenomenon termed colonization resistance. Antibiotics create dysbiosis of microbiota, thereby decreasing colonization resistance and facilitating infections caused by antibiotic-resistant bacteria. Here we describe how cephalosporin antibiotics create dysbiosis in the mouse large intestine, allowing intestinal outgrowth of antimicrobial-resistant Enterococcus faecium. This is accompanied by a reduction of the mucus-associated gut microbiota layer, colon wall, and Muc-2 mucus layer. E. faecium agglutinates intraluminally in an extracellular matrix consisting of secretory IgA (sIgA), polymeric immunoglobulin receptor (pIgR), and epithelial cadherin (E-cadherin) proteins, thereby maintaining spatial segregation of E. faecium from the intestinal wall. Addition of recombinant E-cadherin and pIgR proteins or purified IgA to enterococci in vitro mimics agglutination of E. faecium in vivo. Also, the Ca2+ levels temporarily increased by 75% in feces of antibiotic-treated mice, which led to deformation of E-cadherin adherens junctions between colonic intestinal epithelial cells and release of E-cadherin as an extracellular matrix entrapping E. faecium. These findings indicate that during antibiotic-induced dysbiosis, the intestinal epithelium stays separated from an invading pathogen through an extracellular matrix in which sIgA, pIgR, and E-cadherin are colocalized. Future mucosal vaccination strategies to control E. faecium or other opportunistic pathogens may prevent multidrug-resistant infections, hospital transmission, and outbreaks. PMID:26556272

  7. STAT4 Associates with SLE Through Two Independent Effects that Correlate with Gene Expression and Act Additively with IRF5 to Increase Risk

    PubMed Central

    Abelson, Anna-Karin; Delgado-Vega, Angélica M.; Kozyrev, Sergey V.; Sánchez, Elena; Velázquez-Cruz, Rafael; Eriksson, Niclas; Wojcik, Jerome; Reddy, Prasad Linga; Lima, Guadalupe; D’Alfonso, Sandra; Migliaresi, Sergio; Baca, Vicente; Orozco, Lorena; Witte, Torsten; Ortego-Centeno, Norberto; Abderrahim, Hadi; Pons-Estel, Bernardo A.; Gutiérrez, Carmen; Suárez, Ana; González-Escribano, Maria Francisca; Martin, Javier; Alarcón-Riquelme, Marta E.

    2013-01-01

    Objectives To confirm and define the genetic association of STAT4 and systemic lupus erythematosus, investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. Methods 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in 5 new sets of cases and controls for replication. STAT4 cDNA was analyzed by 5’-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. Results In the fine-mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. We also detected transcription of alternative tissue-specific exons 1, indicating presence of tissue-specific promoters of potential importance in the expression of STAT4. No interaction with associated SNPs of IRF5 was observed using regression analysis. Conclusions These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4. Our results also indicate that both genes STAT4 and IRF5 act additively to increase risk for SLE. PMID:19019891

  8. Homoharringtonine induces apoptosis and inhibits STAT3 via IL-6/JAK1/STAT3 signal pathway in Gefitinib-resistant lung cancer cells

    PubMed Central

    Cao, Wei; Liu, Ying; Zhang, Ran; Zhang, Bo; Wang, Teng; Zhu, Xianbing; Mei, Lin; Chen, Hongbo; Zhang, Hongling; Ming, Pinghong; Huang, Laiqiang

    2015-01-01

    Tyrosine kinase inhibitors (TKIs) are mostly used in non-small cell lung cancer (NSCLC) treatment. Unfortunately, treatment with Gefitinib for a period of time will result in drug resistance and cause treatment failure in clinic. Therefore, exploring novel compounds to overcome this resistance is urgently required. Here we investigated the antitumor effect of homoharringtonine (HHT), a natural compound extracted from Cephalotaxus harringtonia, on Gefitinib-resistant NSCLC cell lines in vitro and in vivo. NCI-H1975 cells with EGFR T790M mutation are more sensitive to HHT treatment compared with that of A549 cells with wild type EGFR. HHT inhibited cells growth, cell viability and colony formation, as well as induced cell apoptosis through mitochondria pathway. Furthermore, we explored the mechanism of HHT inhibition on NSCLC cells. Higher level of interleukin-6 (IL-6) existed in lung cancer patients and mutant EGFR and TGFβ signal requires the upregulation of IL-6 through the gp130/JAK pathway to overactive STAT3, an oncogenic protein which has been considered as a potential target for cancer therapy. HHT reversiblely inhibited IL-6-induced STAT3 Tyrosine 705 phosphorylation and reduced anti-apoptotic proteins expression. Gefitinib-resistant NSCLC xenograft tests also confirmed the antitumor effect of HHT in vivo. Consequently, HHT has the potential in Gefitinib-resistant NSCLC treatment. PMID:26166037

  9. Two Domains of the V Protein of Virulent Canine Distemper Virus Selectively Inhibit STAT1 and STAT2 Nuclear Import▿

    PubMed Central

    Röthlisberger, Anne; Wiener, Dominique; Schweizer, Matthias; Peterhans, Ernst; Zurbriggen, Andreas; Plattet, Philippe

    2010-01-01

    Canine distemper virus (CDV) causes in dogs a severe systemic infection, with a high frequency of demyelinating encephalitis. Among the six genes transcribed by CDV, the P gene encodes the polymerase cofactor protein (P) as well as two additional nonstructural proteins, C and V; of these V was shown to act as a virulence factor. We investigated the molecular mechanisms by which the P gene products of the neurovirulent CDV A75/17 strain disrupt type I interferon (IFN-α/β)-induced signaling that results in the establishment of the antiviral state. Using recombinant knockout A75/17 viruses, the V protein was identified as the main antagonist of IFN-α/β-mediated signaling. Importantly, immunofluorescence analysis illustrated that the inhibition of IFN-α/β-mediated signaling correlated with impaired STAT1/STAT2 nuclear import, whereas the phosphorylation state of these proteins was not affected. Coimmunoprecipitation assays identified the N-terminal region of V (VNT) responsible for STAT1 targeting, which correlated with its ability to inhibit the activity of the IFN-α/β-mediated antiviral state. Conversely, while the C-terminal domain of V (VCT) could not function autonomously, when fused to VNT it optimally interacted with STAT2 and subsequently efficiently suppressed the IFN-α/β-mediated signaling pathway. The latter result was further supported by a single mutation at position 110 within the VNT domain of CDV V protein, resulting in a mutant that lost STAT1 binding while retaining a partial STAT2 association. Taken together, our results identified the CDV VNT and VCT as two essential modules that complement each other to interfere with the antiviral state induced by IFN-α/β-mediated signaling. Hence, our experiments reveal a novel mechanism of IFN-α/β evasion among the morbilliviruses. PMID:20427537

  10. Elevated interleukin-27 levels in human neonatal macrophages regulate indoleamine dioxygenase in a STAT-1 and STAT-3-dependent manner.

    PubMed

    Jung, Joo-Yong; Gleave Parson, Madeline; Kraft, Jennifer D; Lyda, Logan; Kobe, Brianna; Davis, Celestia; Robinson, Jembber; Peña, Maria Marjorette O; Robinson, Cory M

    2016-09-01

    Microbial infections are a major cause of infant mortality as a result of limitations in immune defences. Interleukin-27 (IL-27) is a heterodimeric cytokine produced primarily by leucocytes and is immunosuppressive toward lymphocytes and leucocytes. Our laboratory demonstrated that human neonatal macrophages express IL-27 more abundantly than adult macrophages. Similarly in mice, IL-27 expression is elevated early in life and maintained through infancy. To determine IL-27-regulated mechanisms that may limit immunity, we evaluated the expression of a number of genes in response to this cytokine in primary human neonatal macrophages. Indoleamine 2,3-dioxygenase (IDO) gene expression was increased dose-responsively by IL-27. We have previously demonstrated inhibition of T-cell proliferation and cytokine production by neonatal macrophage-generated IL-27, and IDO is often implicated in this negative regulation. An increase in IDO protein was demonstrated by immunofluorescence microscopy and was consistent with increased enzyme activity following treatment with IL-27. Inclusion of a soluble receptor to neutralize endogenous IL-27, decreased IDO expression and activity compared with untreated macrophages. In response to IL-27, neonatal macrophages phosphorylate signal transdcuer and activator of transcription 1 (STAT-1) and STAT-3. Both transcription factors are recruited to the IDO regulatory region. STAT-3 dominates during steady-state regulation by lower levels of endogenous IL-27 production. A shift to enhanced STAT-1 recruitment occurs during increased levels of exogenously supplied IL-27. These data suggest an interesting interplay of STAT-1 and STAT-3 to regulate IDO activity and immunosuppression in response to different levels of IL-27 in the microenvironment of the immune response that may further our understanding of this interesting cytokine. PMID:27238498

  11. The JAK2 inhibitor AZD1480 potently blocks Stat3 signaling and oncogenesis in solid tumors.

    PubMed

    Hedvat, Michael; Huszar, Dennis; Herrmann, Andreas; Gozgit, Joseph M; Schroeder, Anne; Sheehy, Adam; Buettner, Ralf; Proia, David; Kowolik, Claudia M; Xin, Hong; Armstrong, Brian; Bebernitz, Geraldine; Weng, Shaobu; Wang, Lin; Ye, Minwei; McEachern, Kristen; Chen, Huawei; Morosini, Deborah; Bell, Kirsten; Alimzhanov, Marat; Ioannidis, Stephanos; McCoon, Patricia; Cao, Zhu A; Yu, Hua; Jove, Richard; Zinda, Michael

    2009-12-01

    Persistent activation of Stat3 is oncogenic and is prevalent in a wide variety of human cancers. Chronic cytokine stimulation is associated with Stat3 activation in some tumors, implicating cytokine receptor-associated Jak family kinases. Using Jak2 inhibitors, we demonstrate a central role of Jaks in modulating basal and cytokine-induced Stat3 activation in human solid tumor cell lines. Inhibition of Jak2 activity is associated with abrogation of Stat3 nuclear translocation and tumorigenesis. The Jak2 inhibitor AZD1480 suppresses the growth of human solid tumor xenografts harboring persistent Stat3 activity. We demonstrate the essential role of Stat3 downstream of Jaks by inhibition of tumor growth using short hairpin RNA targeting Stat3. Our data support a key role of Jak kinase activity in Stat3-dependent tumorigenesis. PMID:19962667

  12. Analysis of STAT1 expression and biological activity reveals interferon-tau-dependent STAT1-regulated SOCS genes in the bovine endometrium.

    PubMed

    Vitorino Carvalho, A; Eozenou, C; Healey, G D; Forde, N; Reinaud, P; Chebrout, M; Gall, L; Rodde, N; Padilla, A Lesage; Delville, C Giraud; Leveugle, M; Richard, C; Sheldon, I M; Lonergan, P; Jolivet, G; Sandra, O

    2016-03-01

    Signal transducer and activator of transcription (STAT) proteins are critical for the regulation of numerous biological processes. In cattle, microarray analyses identified STAT1 as a differentially expressed gene in the endometrium during the peri-implantation period. To gain new insights about STAT1 during the oestrous cycle and early pregnancy, we investigated STAT1 transcript and protein expression, as well as its biological activity in bovine tissue and cells of endometrial origin. Pregnancy increased STAT1 expression on Day 16, and protein and phosphorylation levels on Day 20. In cyclic and pregnant females, STAT1 was located in endometrial cells but not in the luminal epithelium at Day 20 of pregnancy. The expression of STAT1 during the oestrous cycle was not affected by progesterone supplementation. In vivo and in vitro, interferon-tau (IFNT) stimulated STAT1 mRNA expression, protein tyrosine phosphorylation and nuclear translocation. Using chromatin immunoprecipitation in IFNT-stimulated endometrial cells, we demonstrated an increase of STAT1 binding on interferon regulatory factor 1 (IRF1), cytokine-inducible SH2-containing protein (CISH), suppressor of cytokine signaling 1 and 3 (SOCS1, SOCS3) gene promoters consistent with the induction of their transcripts. Our data provide novel molecular insights into the biological functions of STAT1 in the various cells composing the endometrium during maternal pregnancy recognition and implantation. PMID:25116692

  13. JAK1 Activates STAT3 Activity in Non-Small-Cell Lung Cancer cells and IL-6 Neutralizing Antibodies can Suppress JAK1-STAT3 Signaling

    PubMed Central

    Song, Lanxi; Rawal, Bhupendra; Nemeth, Jeffrey A.; Haura, Eric B.

    2014-01-01

    Members of the signal transducer and activator of transcription (STAT) family of transcription factors are potential targets for the treatment and prevention of cancers including non-small-cell lung cancer. STAT proteins can be phosphorylated and activated by diverse upstream kinases including cytokine receptors and tyrosine kinases. We examined STAT protein activation in lung cancer cell lines including those with activating mutations in the EGFR and examined upstream kinases responsible for STAT3 phosphorylation and activation using small molecules, antibodies, and RNA interference. We found more pronounced STAT3 activation in cells with activating EGFR mutations yet inhibition of EGFR activity had no effect on STAT3 activation. Inhibition of JAK1 with small molecules or RNA interference resulted in loss of STAT3 tyrosine phosphorylation and inhibition of cell growth. An interleukin-6 neutralizing antibody, siltuximab (CNTO 328) could inhibit STAT3 tyrosine phosphorylation in a cell-dependent manner. Siltuximab could completely inhibit STAT3 tyrosine phosphorylation in H1650 cells and this resulted in inhibition of lung cancer cell growth in vivo. Combined EGFR inhibition with erlotinib and siltuximab resulted in dual inhibition of both tyrosine and serine STAT3 phosphorylation, more pronounced inhibition of STAT3 transcriptional activity, and translated into combined effects on lung cancer growth in a mouse model. Our results suggest that JAK1 is responsible for STAT3 activation in lung cancer cells, and that indirect attacks on JAK1-STAT3 using an IL-6 neutralizing antibody with or without EGFR inhibition can inhibit lung cancer growth in lung cancer subsets. PMID:21216930

  14. Impacts of papain and neuraminidase enzyme treatment on electrohydrodynamics and IgG-mediated agglutination of type A red blood cells.

    PubMed

    Hyono, Atsushi; Gaboriaud, Fabien; Mazda, Toshio; Takata, Youichi; Ohshima, Hiroyuki; Duval, Jérôme F L

    2009-09-15

    The stability of native and enzyme-treated human red blood cells of type A (Rh D positive) against agglutination is investigated under conditions where it is mediated by immunoglobuline G (IgG) anti-D antibody binding. The propensity of cells to agglutinate is related to their interphasic (electrokinetic) properties. These properties significantly depend on the concentration of proteolytic papain enzyme and protease-free neuraminidase enzyme that the cells are exposed to. The analysis is based on the interpretation of electrophoretic data of cells by means of the numerical theory for the electrokinetics of soft (bio)particles. A significant reduction of the hydrodynamic permeability of the external soft glycoprotein layer of the cells is reported under the action of papain. This reflects a significant decrease in soft surface layer thickness and a loss in cell surface integrity/rigidity, as confirmed by nanomechanical AFM analysis. Neuraminidase action leads to an important decrease in the interphase charge density by removing sialic acids from the cell soft surface layer. This is accompanied by hydrodynamic softness modulations less significant than those observed for papain-treated cells. On the basis of these electrohydrodynamic characteristics, the overall interaction potential profiles between two native cells and two enzyme-treated cells are derived as a function of the soft surface layer thickness in the Debye-Hückel limit that is valid for cell suspensions under physiological conditions (approximately 0.16 M). The thermodynamic computation of cell suspension stability against IgG-mediated agglutination then reveals that a decrease in the cell surface layer thickness is more favorable than a decrease in interphase charge density for inducing agglutination. This is experimentally confirmed by agglutination data collected for papain- and neuraminidase-treated cells. PMID:19735140

  15. Properties of Streptococcus mutans Grown in a Synthetic Medium: Binding of Glucosyltransferase and In Vitro Adherence, and Binding of Dextran/Glucan and Glycoprotein and Agglutination

    PubMed Central

    Wu-Yuan, Christine D.; Tai, Stella; Slade, Hutton D.

    1979-01-01

    The influence of culture media on various properties of Streptococcus mutans was investigated. Strains of S. mutans (serotypes c, d, f, and g) were grown in a complex medium (Todd-Hewitt broth [THB]) or a synthetic medium (SYN). The SYN cells, in contrast to THB cells, did not bind extracellular glucosyltransferase and did not produce in vitro adherence. Both types of cells possessed constitutive levels of glucosyltransferase. B13 cells grown in SYN plus invertase-treated glucose possessed the same level of constitutive enzyme as THB cells. In contrast to THB cells, the SYN cells of seven serotype strains did not agglutinate upon the addition of high-molecular-weight dextran/glucan. Significant quantities of lower-molecular-weight (2 × 104 or 7 × 104) dextran and B13 glucan were bound by SYN cells. SYN cells agglutinated weakly in anti-glucan serum (titers, 0 to 16), whereas THB cells possessed titers of 32 to 256. Evidence for the existence of a second binding site in agglutination which does not possess a glucan-like polymer has been obtained. B13 cells grown in invertase-treated THB agglutinated to the same degree as normal THB cells. The nature of this site is unknown. SYN cells possess the type-specific polysaccharide antigen. B13 cells did not bind from THB a glycoprotein which reacts with antisera to the A, B, or T blood group antigens or which allows agglutination upon the addition of dextran. The results demonstrate that S. mutans grown in a chemically defined medium possesse markedly different biochemical and biological activities than cells grown in a complex organic medium. PMID:457252

  16. 2-Guanidinoquinazolines as new inhibitors of the STAT3 pathway

    PubMed Central

    LaPorte, Matthew G.; da Paz Lima, Dimas José; Zhang, Feng; Sen, Malabika; Grandis, Jennifer R.; Camarco, Daniel; Hua, Yun; Johnston, Paul A.; Lazo, John S.; Resnick, Lynn O.; Wipf, Peter; Huryn, Donna M.

    2014-01-01

    Synthesis and SAR investigation of 2-guanidinoquinazolines, initially identified in a high content screen for selective STAT3 pathway inhibitors, led to a more potent analog (11c) that demonstrated improved anti-proliferative activity against a panel of HNSCC cell lines. PMID:25288188

  17. STAT6-dependent and -independent mechanisms in Th2 polarization

    PubMed Central

    Maier, Elisabeth; Duschl, Albert; Horejs-Hoeck, Jutta

    2012-01-01

    Th2 cells play a key role in directing immune responses against helminths. Additionally, Th2 cells are crucial for many types of allergic reactions. Whereas the molecular mechanisms underlying the differentiation of other types of Th cells are well understood, Th2 differentiation is still a controversial topic. IL-4 and its downstream transcription factor signal transducer and activator of transcription (STAT)6 are well-known key mediators in Th2 differentiation. The fact that Th2 cells themselves are the most potent source of IL-4 suggests that additional mechanisms promoting the initiation of Th2 differentiation exist. This article gives an overview on STAT6-dependent and -independent mechanisms involved in the process of Th2 polarization, including Notch, mTORC2, IL-2/STAT5, and Wnt. Furthermore, we emphasize the role of STAT6 not only as a transcriptional activator promoting Th2 development, but also in fine-tuning alternative signaling pathways which are involved in the initiation of Th2 polarization. PMID:23041833

  18. Fun with SFX and stat_object_offline.

    SciTech Connect

    Ou, Carol

    2012-04-01

    SFX's built-in statistical reports can be handy, but sometimes you might want to slice and dice SFX statistics a little more closely than those reports allow. This session will discuss some preliminary efforts to use the data in SFX's stat{_}object{_}offline table to learn more about our users and how they use SFX.

  19. Stat3 Is Important for Follicular Regulatory T Cell Differentiation

    PubMed Central

    Wu, Hao; Xie, Markus M.; Liu, Hong; Dent, Alexander L.

    2016-01-01

    The production of antibody is precisely controlled during the germinal center (GC) reaction. This process is dependent on the help from follicular T helper (Tfh) cells to germinal center (GC) B cells and is regulated by regulatory follicular T helper (Tfr) cells. How Tfr cells develop and how their suppressive activity functions are not well understood. Here, we found that Stat3 is indispensible for Tfr cell differentiation. After immunization with Sheep Red Blood Cells (SRBC), the loss of Tfr cells caused by deletion of Stat3 in Treg cells does not affect the size of Tfh or GC B cell population, but rather leads to strongly enhanced production of antigen-specific IgG1 and IgG2b. In Peyer’s patches (PPs) in the gut, we found that Stat3 expression in Treg cells is also required for Tfr cell formation to commensal organisms. However, loss of Tfr cells in the gut did not affect the numbers of Tfh cells and GC B cells, nor affect IgG1 or IgA switching by GC B cells. Overall, our study has uncovered unique roles of Stat3 in Tfr cell differentiation and the regulation of the antibody response. PMID:27148746

  20. Nuclear unphosphorylated STAT3 correlates with a worse prognosis in human glioblastoma.

    PubMed

    Rodrigues, Bruna R; Queiroz-Hazarbassanov, Nicolle; Lopes, Marilene H; Bleggi-Torres, Luis F; Suzuki, Sérgio; Cunha, Isabela W; Sanematsu, Paulo; Martins, Vilma R

    2016-06-01

    Glioblastoma (GBM) is currently the most aggressive form of brain tumor identified, and STAT3 is known to play an important role in gliomagenesis. Moreover, while several studies have used pharmacological approaches to modulate STAT3 activity, the results have been contradictory. In this study, expressions of STAT3, pSTAT3 (Y705), and pSTAT3 (S727) were evaluated using immunohistochemistry assays of tissue microarrays containing non-neoplastic tissue (NN, n=12), grade II astrocytomas (n=33), grade III astrocytomas (n=12), and GBM (n=85) specimens. In GBM specimens, STAT3 was overexpressed and exhibited greater nuclear localization compared with lower grade astrocytomas and NN. Conversely, nuclear localization of pSTAT3 (Y705) and pSTAT3 (S727) exhibited a similar phenotype in both GBMs and NNs. MET was also detected as a non-canonical pathway marker for STAT3. For tumors with higher levels of STAT3 nuclear localization, and not pSTAT3 (Y705) and pSTAT3 (S727), these specimens exhibited increased levels of MET expression. Thus, a non-canonical pathway may mediate a proportion of the STAT3 that translocates to the nucleus. Moreover, tumors which exhibited greater nuclear localization of STAT3 corresponded with patients that presented with lower rates of recurrence-free survival and overall survival. In contrast, the phosphorylated forms of STAT3 did not correlate with patient survival. These findings suggest that phosphorylation-independent mechanisms may mediate the nuclear translocation and activation of STAT3. Further studies are needed to identify the mechanisms involved, especially those that provide targets to achieve efficient inhibition and control of GBM progression. PMID:27013058

  1. Methotrexate Is a JAK/STAT Pathway Inhibitor

    PubMed Central

    Thomas, Sally; Fisher, Katherine H.; Snowden, John A.; Danson, Sarah J.; Brown, Stephen; Zeidler, Martin P.

    2015-01-01

    Background The JAK/STAT pathway transduces signals from multiple cytokines and controls haematopoiesis, immunity and inflammation. In addition, pathological activation is seen in multiple malignancies including the myeloproliferative neoplasms (MPNs). Given this, drug development efforts have targeted the pathway with JAK inhibitors such as ruxolitinib. Although effective, high costs and side effects have limited its adoption. Thus, a need for effective low cost treatments remains. Methods & Findings We used the low-complexity Drosophila melanogaster pathway to screen for small molecules that modulate JAK/STAT signalling. This screen identified methotrexate and the closely related aminopterin as potent suppressors of STAT activation. We show that methotrexate suppresses human JAK/STAT signalling without affecting other phosphorylation-dependent pathways. Furthermore, methotrexate significantly reduces STAT5 phosphorylation in cells expressing JAK2 V617F, a mutation associated with most human MPNs. Methotrexate acts independently of dihydrofolate reductase (DHFR) and is comparable to the JAK1/2 inhibitor ruxolitinib. However, cells treated with methotrexate still retain their ability to respond to physiological levels of the ligand erythropoietin. Conclusions Aminopterin and methotrexate represent the first chemotherapy agents developed and act as competitive inhibitors of DHFR. Methotrexate is also widely used at low doses to treat inflammatory and immune-mediated conditions including rheumatoid arthritis. In this low-dose regime, folate supplements are given to mitigate side effects by bypassing the biochemical requirement for DHFR. Although independent of DHFR, the mechanism-of-action underlying the low-dose effects of methotrexate is unknown. Given that multiple pro-inflammatory cytokines signal through the pathway, we suggest that suppression of the JAK/STAT pathway is likely to be the principal anti-inflammatory and immunosuppressive mechanism-of-action of low

  2. FastStats: A to Z

    MedlinePlus

    ... Care Nursing Home Care Residential Care Communities Screenings Mammography Pap Tests Disability and Risk Factors Alcohol Use ... Liver Disease/Cirrhosis Lung Diseases Chronic Obstructive M Mammography Marriage Measles, Mumps, and Rubella Men's Health Mental ...

  3. Profibrogenic phenotype in caveolin-1 deficiency via differential regulation of STAT-1/3 proteins.

    PubMed

    Ryter, Stefan W; Choi, Augustine M K; Kim, Hong Pyo

    2014-10-01

    Fibrosis underlies the pathogenesis of several human diseases, which can lead to severe injury of vital organs. We previously demonstrated that caveolin-1 expression is reduced in experimental fibrosis and that caveolin-1 exerts antiproliferative and antifibrotic effects in lung fibrosis models. The signal transducers and activators of transcription (STAT) proteins, STAT1 and STAT3, can be activated simultaneously. STAT1 can inhibit cell growth and promote apoptosis while STAT3 inhibits apoptosis. Here, we show that caveolin-1-deficient (cav-1(-/-)) lung fibroblasts display dramatically upregulated STAT3 activation in response to platelet-derived growth factor-BB and transforming growth factor-β stimuli, whereas STAT1 activation is undetectable. Downregulation of protein tyrosine phosphatase-1B played a role in the preferential activation of STAT3 in cav-1(-/-) fibroblasts. Genetic deletion of STAT3 by siRNA modulated the expression of genes involved in cell proliferation and fibrogenesis. Basal expression of α-smooth muscle actin was prominent in cav-1(-/-) liver and kidney, consistent with deposition of collagen in these organs. Collectively, we demonstrate that the antiproliferative and antifibrogenic properties of caveolin-1 in vitro are mediated by the balance between STAT1 and STAT3 activation. Deregulated STAT signaling associated with caveolin-1 deficiency may be relevant to proliferative disorders such as tissue fibrosis. PMID:25263949

  4. Truncated pStat5B is associated with the Idd4 locus in NOD mice

    SciTech Connect

    Davoodi-Semiromi, Abdoreza . E-mail: semiromi@pathology.ufl.edu; McDuffie, Marcia; Litherland, Sally; Clare-Salzler, Michael

    2007-05-11

    We investigate JAK-STAT5 activation and its relationship to full-length Stat5B (FL-Stat5) and constitutive phosphorylated carboxy-truncated Stat5B (ct-pStat5) in four different strains of mouse. Our electrophoresis mobility shift assays data indicate constitutive phosphorylation of full-length-Stat5 (p < 0.001) and DNA binding in NOD but not in B6 mice. Our data suggest that the relative ratio of FL-Stat5: ct-Stat5 in NOD is 5- to 8-fold lower (p < 0.0001) when compared with normal B6 mice. Additionally, EMSAs data from B6.NOD/c11 suggest contribution of Idd4 susceptibility locus on chromosome 11 in constitutive phosphorylation of Stat5 in NOD mice. The presence of ct-pStat5 in regulatory T cells of NOD mice suggests this form of Stat5 is associated with impaired function of Tregs in NOD mouse. In agreement with our previous report the JAK-Stat5B defective pathway in NOD mice along with other defective factors is associated with the pathogenesis of autoimmune type 1 diabetes in NOD mice.

  5. Mutational analysis of acute-phase response factor/Stat3 activation and dimerization.

    PubMed Central

    Sasse, J; Hemmann, U; Schwartz, C; Schniertshauer, U; Heesel, B; Landgraf, C; Schneider-Mergener, J; Heinrich, P C; Horn, F

    1997-01-01

    Signal transducer and transcription (STAT) factors are activated by tyrosine phosphorylation in response to a variety of cytokines, growth factors, and hormones. Tyrosine phosphorylation triggers dimerization and nuclear translocation of these transcription factors. In this study, the functional role of carboxy-terminal portions of the STAT family member acute-phase response factor/Stat3 in activation, dimerization, and transactivating potential was analyzed. We demonstrate that truncation of 55 carboxy-terminal amino acids causes constitutive activation of Stat3 in COS-7 cells, as is known for the Stat3 isoform Stat3beta. By the use of deletion and point mutants, it is shown that both carboxy- and amino-terminal portions of Stat3 are involved in this phenomenon. Dimerization of Stat3 was blocked by point mutations affecting residues both in the vicinity of the tyrosine phosphorylation site (Y705) and more distant from this site, suggesting that multiple interactions are involved in dimer formation. Furthermore, by reporter gene assays we demonstrate that carboxy-terminally truncated Stat3 proteins are incapable of transactivating an interleukin-6-responsive promoter in COS-7 cells. In HepG2 hepatoma cells, however, these truncated Stat3 forms transmit signals from the interleukin-6 signal transducer gp130 equally well as does full-length Stat3. We conclude that, dependent on the cell type, different mechanisms allow Stat3 to regulate target gene transcription either with or without involvement of its putative carboxy-terminal transactivation domain. PMID:9234724

  6. Differences in antiproliferative effect of STAT3 inhibition in HCC cells with versus without HBV expression

    SciTech Connect

    Hong, Yun; Zhou, Lin; Xie, Haiyang; Wang, Weilin; Zheng, Shusen

    2015-06-05

    Chronic infection with hepatitis B virus (HBV) plays an important role in the etiology of hepatocellular carcinoma (HCC). Signal transducer and activator of transcription 3 (STAT3) inactivation could inhibit the tumor growth of HCC. In this study, differential antiproliferative effect of STAT3 inhibition was observed with HBV-related HCC cells being more resistant than non-HBV-related HCC cells. Resistance of HBV-related HCC cells to STAT3 inhibition was positively correlated to the expression of HBV. Enhanced ERK activation after STAT3 blockade was detected in HBV-related HCC cells but not in non-HBV-related HCC cells. Combined ERK and STAT3 inhibition eliminates the discrepancy between the two types of HCC cells. Moderate reduced HBV expression was found after STAT3 inhibition. These findings disclose a discrepancy in cellular response to STAT3 inhibition between non-HBV-related and HBV-related HCC cells and underscore the complexity of antiproliferative effect of STAT3 inactivation in HBV-related HCC cells. - Highlights: • HBV endows HCC cells with resistance to STAT3 inactivation on proliferation. • Abnormal ERK activation after STAT3 inhibition in HBV-related HCC cells. • Combined ERK and STAT3 inhibition eliminates the discrepancy. • STAT3 inhibition moderately reduces HBV expression.

  7. STAT3 Serine 727 Phosphorylation: A Relevant Target to Radiosensitize Human Glioblastoma.

    PubMed

    Ouédraogo, Zangbéwendé Guy; Müller-Barthélémy, Mélanie; Kemeny, Jean-Louis; Dedieu, Véronique; Biau, Julian; Khalil, Toufic; Raoelfils, Lala Ines; Granzotto, Adeline; Pereira, Bruno; Beaudoin, Claude; Guissou, Innocent Pierre; Berger, Marc; Morel, Laurent; Chautard, Emmanuel; Verrelle, Pierre

    2016-01-01

    Radiotherapy is an essential component of glioma standard treatment. Glioblastomas (GBM), however, display an important radioresistance leading to tumor recurrence. To improve patient prognosis, there is a need to radiosensitize GBM cells and to circumvent the mechanisms of resistance caused by interactions between tumor cells and their microenvironment. STAT3 has been identified as a therapeutic target in glioma because of its involvement in mechanisms sustaining tumor escape to both standard treatment and immune control. Here, we studied the role of STAT3 activation on tyrosine 705 (Y705) and serine 727 (S727) in glioma radioresistance. This study explored STAT3 phosphorylation on Y705 (pSTAT3-Y705) and S727 (pSTAT3-S727) in glioma cell lines and in clinical samples. Radiosensitizing effect of STAT3 activation down-modulation by Gö6976 was explored. In a panel of 15 human glioma cell lines, we found that the level of pSTAT3-S727 was correlated to intrinsic radioresistance. Moreover, treating GBM cells with Gö6976 resulted in a highly significant radiosensitization associated to a concomitant pSTAT3-S727 down-modulation only in GBM cell lines that exhibited no or weak pSTAT3-Y705. We report the constitutive activation of STAT3-S727 in all GBM clinical samples. Targeting pSTAT3-S727 mainly in pSTAT3-Y705-negative GBM could be a relevant approach to improve radiation therapy. PMID:25736961

  8. The JAK/STAT signaling cascade in gastric carcinoma (Review).

    PubMed

    Khanna, Puja; Chua, Pei Jou; Bay, Boon Huat; Baeg, Gyeong Hun

    2015-11-01

    Gastric carcinoma remains one of the most prevalent forms of cancer worldwide, despite the decline in incidence rates, increased awareness of the disease and advancement in treatment strategies. Helicobacter pylori infection, dietary factors, lifestyle influences and various genetic aberrations have been shown to contribute to the development and progression of gastric cancer. Recent studies on the genomic landscape of gastric adenocarcinoma have identified several key signaling molecules, including epidermal growth factor receptor family (ErbB) members, vascular endothelial growth factor receptor family (VEGFR) members and PI3K/Akt/mTOR pathway components, that have been implicated in the molecular pathogenesis of gastric cancers. However, clinical trials with compounds that target these molecules have failed to show a significant improvement in overall survival rates when supplemented with conventional therapies. Therefore, it is essential to identify effective prognostic and/or diagnostic biomarkers and develop molecular targeted therapies. The JAK/STAT cascade is a principal signal transduction pathway in cytokine and growth factor signaling, regulating various cellular processes such as cell proliferation, differentiation, migration and survival. Numerous in vivo and in vitro studies have shown that dysregulated JAK/STAT signaling is a driving force in the pathogenesis of various solid cancers as well as hematopoietic malignancies. Hence, a large number of preclinical and clinical studies of drugs targeting this pathway are currently underway. Notably, aberrant JAK/STAT signaling has also been implicated in gastric cancers. In this review, we focus on the ongoing research on the JAK/STAT cascade in gastric carcinoma and discuss the therapeutic potential of targeting JAK/STAT signaling for the treatment of gastric cancer. PMID:26398764

  9. The reliability of the i-STAT clinical portable analyser.

    PubMed

    Dascombe, B J; Reaburn, P R J; Sirotic, A C; Coutts, A J

    2007-06-01

    The purpose of this investigation was to assess the reliability of the i-STAT clinical portable analyser and CG(4)(+) cartridge measures of blood pH, partial pressures of O(2) (pO(2)) and CO(2) (pCO(2)), bicarbonate ([HCO(3)(-)]), base excess (BE), total carbon dioxide (TCO(2)), oxygen saturation (sO(2)) and blood lactate ([BLa(-)]) at various exercise intensities. A comparison between [BLa(-)] measured by the i-STAT and the Accusport lactate analysers during an intermittent treadmill run was also undertaken. The technical error of measurement (TEM%) at rest, at moderate (200W) and maximal exercise (V O(2)max) was acceptable (<15%) for all parameters. The intra-class correlation coefficients for each analyte ranged from weak-to-strong across resting (ICC=0.19-0.96) and moderate (ICC=0.30-0.96) exercise intensities. The ICC for all analytes were observed to be strong following maximal intensity exercise (ICC=0.77-0.95). The comparison of the [BLa(-)] measures between the i-STAT and Accusport showed that the difference between measures was acceptable at both low (<4mmolL(-1)) (-0.39+/-0.27mmolL(-1)), moderate to high concentrations (>4mmolL(-1)) (0.58+/-1.22mmolL(-1)), and across all [BLa(-)] data (0.36+/-1.13mmolL(-1)). In conclusion, the i-STAT clinical analyser and CG(4)(+) cartridge provides reliable measures of a number of blood parameters across exercise intensities. The [BLa(-)] measures from the i-STAT analyser are consistent with that of the Accusport lactate analyser. PMID:16846754

  10. A Streamflow Statistics (StreamStats) Web Application for Ohio

    USGS Publications Warehouse

    Koltun, G.F.; Kula, Stephanie P.; Puskas, Barry M.

    2006-01-01

    A StreamStats Web application was developed for Ohio that implements equations for estimating a variety of streamflow statistics including the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year peak streamflows, mean annual streamflow, mean monthly streamflows, harmonic mean streamflow, and 25th-, 50th-, and 75th-percentile streamflows. StreamStats is a Web-based geographic information system application designed to facilitate the estimation of streamflow statistics at ungaged locations on streams. StreamStats can also serve precomputed streamflow statistics determined from streamflow-gaging station data. The basic structure, use, and limitations of StreamStats are described in this report. To facilitate the level of automation required for Ohio's StreamStats application, the technique used by Koltun (2003)1 for computing main-channel slope was replaced with a new computationally robust technique. The new channel-slope characteristic, referred to as SL10-85, differed from the National Hydrography Data based channel slope values (SL) reported by Koltun (2003)1 by an average of -28.3 percent, with the median change being -13.2 percent. In spite of the differences, the two slope measures are strongly correlated. The change in channel slope values resulting from the change in computational method necessitated revision of the full-model equations for flood-peak discharges originally presented by Koltun (2003)1. Average standard errors of prediction for the revised full-model equations presented in this report increased by a small amount over those reported by Koltun (2003)1, with increases ranging from 0.7 to 0.9 percent. Mean percentage changes in the revised regression and weighted flood-frequency estimates relative to regression and weighted estimates reported by Koltun (2003)1 were small, ranging from -0.72 to -0.25 percent and -0.22 to 0.07 percent, respectively.

  11. STAT3 polymorphisms may predict an unfavorable response to first-line platinum-based therapy for women with advanced serous epithelial ovarian cancer

    PubMed Central

    Permuth-Wey, Jennifer; Fulp, William J.; Reid, Brett M.; Chen, Zhihua; Georgeades, Christina; Cheng, Jin Q.; Magliocco, Anthony; Chen, Dung-Tsa; Lancaster, Johnathan M.

    2016-01-01

    Cancer stem cells (CSC) contribute to epithelial ovarian cancer (EOC) progression and therapeutic response. We hypothesized that germline single nucleotide polymorphisms (SNPs) in CSC-related genes may predict an initial therapeutic response for women newly diagnosed with EOC. A nested case–control design was used to study 361 women with advanced-stage serous EOC treated with surgery followed by first-line platinum-based combination therapy at Moffitt Cancer Center or as part of The Cancer Genome Atlas Study. “Cases” included 102 incomplete responders (IRs) and “controls” included 259 complete clinical responders (CRs) to therapy. Using Illumina genotyping arrays and imputation, DNA samples were evaluated for 5,509 SNPs in 24 ovarian CSC-related genes. We also evaluated the overall significance of each CSC gene using the admixture maximum likelihood (AML) test, and correlated genotype with EOC tumor tissue expression. The strongest SNP-level associations with an IR to therapy were identified for correlated (r2 > 0.80) SNPs within signal transducer and activator of transcription 3 (STAT3) [odds ratio (OR), 2.24; 95% confidence interval (CI), 1.32–3.78; p = 0.0027], after adjustment for age, population stratification, grade and residual disease. At the gene level, STAT3 was significantly associated with an IR to therapy (pAML 5 0.006). rs1053004, a STAT3 SNP in a putative miRNA-binding site, was associated with STAT3 expression (p = 0.057). This is the first study to identify germline STAT3 variants as independent predictors of an unfavorable therapeutic response for EOC patients. Findings suggest that STAT3 genotype may identify high-risk women likely to respond more favorably to novel therapeutic combinations that include STAT3 inhibitors. PMID:26264211

  12. Scutellaria barbata D. Don inhibits growth and induces apoptosis by suppressing IL-6-inducible STAT3 pathway activation in human colorectal cancer cells

    PubMed Central

    JIANG, QIQIN; LI, QIONGYU; CHEN, HONGWEI; SHEN, ALING; CAI, QIAOYAN; LIN, JIUMAO; PENG, JUN

    2015-01-01

    One of the most critical cellular signal transduction pathways known to malfunction in colorectal cancer is the interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) pathway. Scutellaria barbata D. Don (SB) is well-known traditional medicine in China that targets STAT3 signaling, and it has long been used to treat various types of cancer; however, the precise mechanism of its antitumor activity remains largely unclear. In order to further elucidate this underlying mechanism, an ethanol extract of SB (EESB) in cancer treatment. The aim of the present study was to evaluate the effects of EESB on the IL-6-inducible STAT3 pathway. We tested the dose-response association between EESB, IL-6-induced proliferaion and apoptosis using an MTT assay, colony formation and flow cytometry analysis in vitro. In addition, caspase-9 and caspase-3 activation was determined using a colorimetric assay, the activity of IL-6-induced STAT3 pathway was evaluated using western blot analysis, and the expression levels of cyclin D1, cyclin-dependent kinase 4, Bcl2 and Bcl2-associated X were determined using reverse transcription-polymerase chain reaction and western blot analysis. In the present study it was found that EESB could significantly inhibit the IL-6-mediated increase in STAT3 phosphorylation levels and transcriptional activity in HT-29 human colon carcinoma cells, resulting in the suppression of cell proliferation and the induction of apoptosis. In addition, treatment with EESB markedly inhibited the IL-6-induced upregulation of cyclin D1 and B-cell lymphoma-2, two key target genes of the STAT3 pathway. These results suggest that treatment with EESB could effectively inhibit the proliferation and promote the apoptosis of human colon carcinoma cells via modulation of the IL-6/STAT3 signaling pathway and its target genes. PMID:26622533

  13. STAT3 polymorphisms may predict an unfavorable response to first-line platinum-based therapy for women with advanced serous epithelial ovarian cancer.

    PubMed

    Permuth-Wey, Jennifer; Fulp, William J; Reid, Brett M; Chen, Zhihua; Georgeades, Christina; Cheng, Jin Q; Magliocco, Anthony; Chen, Dung-Tsa; Lancaster, Johnathan M

    2016-02-01

    Cancer stem cells (CSC) contribute to epithelial ovarian cancer (EOC) progression and therapeutic response. We hypothesized that germline single nucleotide polymorphisms (SNPs) in CSC-related genes may predict an initial therapeutic response for women newly diagnosed with EOC. A nested case-control design was used to study 361 women with advanced-stage serous EOC treated with surgery followed by first-line platinum-based combination therapy at Moffitt Cancer Center or as part of The Cancer Genome Atlas Study. "Cases" included 102 incomplete responders (IRs) and "controls" included 259 complete clinical responders (CRs) to therapy. Using Illumina genotyping arrays and imputation, DNA samples were evaluated for 5,509 SNPs in 24 ovarian CSC-related genes. We also evaluated the overall significance of each CSC gene using the admixture maximum likelihood (AML) test, and correlated genotype with EOC tumor tissue expression. The strongest SNP-level associations with an IR to therapy were identified for correlated (r(2) > 0.80) SNPs within signal transducer and activator of transcription 3 (STAT3) [odds ratio (OR), 2.24; 95% confidence interval (CI), 1.32-3.78; p = 0.0027], after adjustment for age, population stratification, grade and residual disease. At the gene level, STAT3 was significantly associated with an IR to therapy (pAML = 0.006). rs1053004, a STAT3 SNP in a putative miRNA-binding site, was associated with STAT3 expression (p = 0.057). This is the first study to identify germline STAT3 variants as independent predictors of an unfavorable therapeutic response for EOC patients. Findings suggest that STAT3 genotype may identify high-risk women likely to respond more favorably to novel therapeutic combinations that include STAT3 inhibitors. PMID:26264211

  14. 'Papillary' solitary fibrous tumor/hemangiopericytoma with nuclear STAT6 expression and NAB2-STAT6 fusion.

    PubMed

    Ishizawa, Keisuke; Tsukamoto, Yoshitane; Ikeda, Shunsuke; Suzuki, Tomonari; Homma, Taku; Mishima, Kazuhiko; Nishikawa, Ryo; Sasaki, Atsushi

    2016-04-01

    This report describes clinicopathological findings, including genetic data of STAT6, in a solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) of the central nervous system in an 83-year-old woman with a bulge in the left forehead. She noticed it about 5 months before, and it had grown rapidly for the past 1 month. Neuroradiological studies disclosed a well-demarcated tumor that accompanied the destruction of the skull. The excised tumor showed a prominent papillary structure, where atypical cells were compactly arranged along the fibrovascular core ('pseudopapillary'). There was rich vasculature, some of which resembled 'staghorn' vessels. Mitotic figures were occasionally found. Whorls, psammoma bodies, or intra-nuclear pseudoinclusions were not identified. By immunohistochemistry, CD34 was strongly positive in the tumor cells, and STAT6 was localized in their nuclei. By reverse transcription-polymerase chain reaction (RT-PCR), an NAB2-STAT6 fusion gene, NAB2 exon6-STAT6 exon17, was detected, establishing a definite diagnosis of SFT/HPC. 'Papillary' SFT/HPC needs to be recognized as a possible morphological variant of SFT/HPC, and should be borne in mind in its diagnostic practice. PMID:26746203

  15. Global changes in STAT target selection and transcription regulation upon interferon treatments

    PubMed Central

    Hartman, Stephen E.; Bertone, Paul; Nath, Anjali K.; Royce, Thomas E.; Gerstein, Mark; Weissman, Sherman; Snyder, Michael

    2005-01-01

    The STAT (signal transducer and activator of transcription) proteins play a crucial role in the regulation of gene expression, but their targets and the manner in which they select them remain largely unknown. Using chromatin immunoprecipitation and DNA microarray analysis (ChIP-chip), we have identified the regions of human chromosome 22 bound by STAT1 and STAT2 in interferon-treated cells. Analysis of the genomic loci proximal to these binding sites introduced new candidate STAT1 and STAT2 target genes, several of which are affiliated with proliferation and apoptosis. The genes on chromosome 22 that exhibited interferon-induced up- or down-regulated expression were determined and correlated with the STAT-binding site information, revealing the potential regulatory effects of STAT1 and STAT2 on their target genes. Importantly, the comparison of STAT1-binding sites upon interferon (IFN)-γ and IFN-α treatments revealed dramatic changes in binding locations between the two treatments. The IFN-α induction revealed nonconserved STAT1 occupancy at IFN-γ-induced sites, as well as novel sites of STAT1 binding not evident in IFN-γ-treated cells. Many of these correlated with binding by STAT2, but others were STAT2 independent, suggesting that multiple mechanisms direct STAT1 binding to its targets under different activation conditions. Overall, our results reveal a wealth of new information regarding IFN/STAT-binding targets and also fundamental insights into mechanisms of regulation of gene expression in different cell states. PMID:16319195

  16. Molecular cloning and expression analysis of the STAT1 gene from olive flounder, Paralichthys olivaceus

    PubMed Central

    Park, Eun-Mi; Kang, Jung-Ha; Seo, Jung Soo; Kim, GunDo; Chung, Jongkyeong; Choi, Tae-Jin

    2008-01-01

    Background Signal transducer and activator of transcription 1 (STAT1) is a critical component of interferon (IFN)-alpha/beta and IFN-gamma signaling. Although seven isoforms of STAT proteins have been reported from mammals, limited information is available for the STAT genes in fish. We isolated complementary DNA with high similarity to mammalian STAT1 from the olive flounder, Paralichthys olivaceus. Results A DNA fragment containing the conserved SH2 domain was amplified by RT-PCR using degenerate primers designed based on the highly conserved sequences in the SH2 domains of the zebrafish and mammalian STAT1. The complete cDNA sequence was obtained by 5' and 3' RACE. The flounder STAT1 transcript consisted of 2,909 bp that encoded a polypeptide of 749 amino acids. The overall similarity between flounder STAT1 and other STATs was very high, with the highest amino acid sequence identity to snakehead (89%). Phylogenetic analyses reveal that flounder STAT1 is in the same monophyletic group with snakehead STAT1. Quantitative real time RT-PCR and in situ hybridization revealed that STAT1 was expressed in almost all examined organs and tissues, with high expression in gill, spleen, kidney, and heart. The accumulation of STAT1 mRNA in different developmental stages, as determined by real time RT-PCR, increased with development. Conclusion Recent cloning of various cytokine genes and the STAT1 gene of olive flounder here suggest that fish also use the highly specialized JAK-STAT pathway for cytokine signaling. Identification of other STAT genes will elucidate in detail the signal transduction system in this fish. PMID:18578892

  17. Live-Cell Imaging of the Association of STAT6-GFP with Mitochondria

    PubMed Central

    Khan, Rasel; Lee, Jason E.; Yang, Yang-Ming; Liang, Feng-Xia; Sehgal, Pravin B.

    2013-01-01

    The transcription factor STAT3 has been previously reported to be associated with mitochondria. However, we have been unable to visualize an association of STAT3-GFP, STAT3-DsRed or STAT3-Flag with mitochondria in human Hep3B hepatocytes thus far even though an association of these molecules with other cytoplasmic organelles (endosomes) was readily demonstrable. We then addressed the broader question of a possible association of other STAT-family of proteins with mitochondria by first using immunolocalization assays in Hep3B and human pulmonary arterial endothelial and smooth muscle cells. Strong anti-STAT6-immunolocalization with mitochondria was apparent in fluorescence and electron microscopy assays of cells first washed with a digitonin-sucrose buffer to remove bulk soluble STAT proteins. In live-cell imaging studies, STAT6-GFP, but not N1-GFP, was observed to constitutively colocalize with MitoTracker- and tetramethylrhodamine ethyl ester (TMRE)-positive mitochondria, and with mitochondrial F1-ATPase when assayed by immunofluorescence after fixation. This association was Tyr-phosphorylation independent in that a STAT6 truncated protein (STAT61-459-GFP) which lacked the SH2 domain (517–632) and the cytokine-activated Y641 phosphorylation site also accumulated in MitoTracker-positive mitochondria. This was consistent with the unexpected discovery that anti-STAT6-immunofluoresence also associated with mitochondria in mouse embryo fibroblasts (MEFs) from both wild-type and the STAT6SH2-/SH2- mouse. MEFs from the latter mouse, which had been engineered in 1996 to be deleted in the STAT6 SH2 domain (amino acids 505–584) expressed an immune-specific ∼50 kDa protein detectable in whole cell and mitochondria-enriched fractions. Taken together, the present data provide the first definitive evidence of the association of any STAT-protein family member with mitochondria - that of STAT6. PMID:23383189

  18. Salidroside attenuates inflammatory response via suppressing JAK2-STAT3 pathway activation and preventing STAT3 transfer into nucleus.

    PubMed

    Qi, Zhilin; Qi, Shimei; Ling, Liefeng; Lv, Jun; Feng, Zunyong

    2016-06-01

    Salidroside (SAL) is an active ingredient isolated from the Rhodiola rosea, has potent anti-inflammatory effect, but the mechanism is still elusive. The purpose of this study is to verify the effects of SAL on LPS-induced inflammatory response and investigate the possible underlying molecular mechanism. RAW264.7 cells were pre-incubated with SAL for 2h, then stimulated with or without LPS for another 16h. The levels of TNF-α, MCP-1, IL-6, and PGE2 were detected by ELISA, and the production of NO was determined by nitrite analysis. The expression levels of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected by Western blotting. In RAW264.7 cells and murine peritoneal macrophages, the activation of signal molecules was also measured by Western blot. The nuclear translocation of STAT3 was determined by Laser confocal and nucleocytoplasmic separation experiments. Our results showed that SAL attenuated the productions of TNF-α, IL-6, MCP-1, PGE2 and NO dose dependently. SAL also suppressed LPS-induced expressions of iNOS and COX-2 significantly. Further studies revealed that SAL down-regulated the phosphorylation of JAK2-STAT3 signaling pathway and reduced the nuclear translocation of STAT3 induced by LPS in RAW264.7 cells and primary peritoneal macrophages. In addition, consistent with the results in vitro, in the model of mice acute lung injury (ALI) induced by LPS, SAL reduced the infiltration of inflammatory cells and decreased the levels of serum TNF-α and IL-6 obviously. Taken together, these data indicated that SAL exerted anti-inflammatory action via down-regulating LPS-induced activation of JAK2-STAT3 pathway and suppressing STAT3 transfer into the nucleus at least in part. PMID:27085677

  19. STAT3 as a target for inducing apoptosis in solid and hematological tumors

    PubMed Central

    Siddiquee, Khandaker Al Zaid; Turkson, James

    2008-01-01

    Studies in the past few years have provided compelling evidence for the critical role of aberrant Signal Transducer and Activator of Transcription 3 (STAT3) in malignant transformation and tumorigenesis. Thus, it is now generally accepted that STAT3 is one of the critical players in human cancer formation and represents a valid target for novel anticancer drug design. This review focuses on aberrant STAT3 and its role in promoting tumor cell survival and supporting the malignant phenotype. A brief evaluation of the current strategies targeting STAT3 for the development of novel anticancer agents against human tumors harboring constitutively active STAT3 will also be presented. PMID:18227858

  20. Crispene E, a cis-clerodane diterpene inhibits STAT3 dimerization in breast cancer cells.

    PubMed

    Mantaj, Julia; Rahman, S M Abdur; Bokshi, Bishwajit; Hasan, Choudhury M; Jackson, Paul J M; Parsons, Richard B; Rahman, Khondaker M

    2015-04-01

    Crispene E, a new clerodane-type diterpene, inhibited STAT3 dimerization in a cell-free fluorescent polarisation assay and was found to have significant toxicity against STAT3-dependent MDA-MB 231 breast cancer cell line and selectively inhibited the expression of STAT3 and STAT3 target genes cyclin D1, Fascin and bcl-2. Molecular docking studies suggest the molecule inhibits STAT3 by interacting with its SH2 domain. The compound has been isolated from Tinospora crispa and characterized using standard spectroscopic techniques. PMID:25721973

  1. Trichosanthes kirilowii Ethanol Extract and Cucurbitacin D Inhibit Cell Growth and Induce Apoptosis through Inhibition of STAT3 Activity in Breast Cancer Cells

    PubMed Central

    Kim, Soon Re; Seo, Hye Sook; Choi, Han-Seok; Cho, Sung-Gook; Kim, Yong Kuk; Hong, Eun Hee; Shin, Yong Cheol; Ko, Seong-Gyu

    2013-01-01

    Trichosanthes kirilowii tuber is a traditional medicine which exhibits various medicinal effects including antidiabetic and anticancer activities in several cancer cells. Recently, it was reported that Cucurbitacin D (CuD) isolated from Trichosanthes kirilowii also induces apoptosis in several cancer cells. Constitutive signal transducer and activator of transcription 3 (STAT3), which is an oncogenic transcription factor, is often observed in many human malignant tumor, including breast cancer. In the present study, we tested whether Trichosanthes kirilowii ethanol extract (TKE) or CuD suppresses cell growth and induces apoptosis through inhibition of STAT3 activity in breast cancer cells. We found that both TKE and CuD suppressed proliferation and induced apoptosis and G2/M cell cycle arrest in MDA-MB-231 breast cancer cells by inhibiting STAT3 phosphorylation. In addition, both TKE and CuD inhibited nuclear translocation and transcriptional activity of STAT3. Taken together, our results indicate that TKE and its derived compound, CuD, could be potent therapeutic agents for breast cancer, blocking tumor cell proliferation and inducing apoptosis through suppression of STAT3 activity. PMID:24194785

  2. STAT3 mutations indicate the presence of subclinical T-cell clones in a subset of aplastic anemia and myelodysplastic syndrome patients

    PubMed Central

    Jerez, Andres; Clemente, Michael J.; Makishima, Hideki; Rajala, Hanna; Gómez-Seguí, Ines; Olson, Thomas; McGraw, Kathy; Przychodzen, Bartlomiej; Kulasekararaj, Austin; Afable, Manuel; Husseinzadeh, Holleh D.; Hosono, Naoko; LeBlanc, Francis; Lagström, Sonja; Zhang, Dan; Ellonen, Pekka; Tichelli, André; Nissen, Catherine; Lichtin, Alan E.; Wodnar-Filipowicz, Aleksandra; Mufti, Ghulam J.; List, Alan F.; Mustjoki, Satu; Loughran, Thomas P.

    2013-01-01

    Large granular lymphocyte leukemia (LGL) is often associated with immune cytopenias and can cooccur in the context of aplastic anemia (AA) and myelodysplastic syndromes (MDS). We took advantage of the recent description of signal transducer and activator of transcription 3 (STAT3) mutations in LGL clonal expansions to test, using sensitive methods, for the presence of these mutations in a large cohort of 367 MDS and 140 AA cases. STAT3 clones can be found not only in known LGL concomitant cases, but in a small proportion of unsuspected ones (7% AA and 2.5% MDS). In STAT3-mutated AA patients, an interesting trend toward better responses of immunosuppressive therapy and an association with the presence of human leukocyte antigen-DR15 were found. MDSs harboring a STAT3 mutant clone showed a lower degree of bone marrow cellularity and a higher frequency of developing chromosome 7 abnormalities. STAT3-mutant LGL clones may facilitate a persistently dysregulated autoimmune activation, responsible for the primary induction of bone marrow failure in a subset of AA and MDS patients. PMID:23926297

  3. Interleukin 2 and erythropoietin activate STAT5/MGF via distinct pathways.

    PubMed Central

    Wakao, H; Harada, N; Kitamura, T; Mui, A L; Miyajima, A

    1995-01-01

    Signal transducers and activators of transcription (STAT) proteins play an important role in cytokine signal transduction in conjunction with Janus kinases (JAKs). MGF/STAT5 is known as prolactin regulated STAT. Here we demonstrate that interleukin 2 (IL-2) as well as erythropoietin (EPO) stimulate STAT5 and induce tyrosine phosphorylation of STAT5. These IL-2- and EPO-induced STATs have an identical DNA binding specificity and immunoreactivity. We also show that IL-4 induces a DNA binding factor which possesses similar, but distinct, DNA binding specificity from that of STAT5 and is immunologically different from STAT5. Analysis of two EPO receptor (EPOR) transfected CTLL-2 cell lines discloses that IL-2 activates JAK1 and JAK3 as well as STAT5, while EPO stimulates STAT5 and JAK2 in EPO-responsive CTLL-2 cells (ERT/E2). On the contrary, EPO activates neither JAK2 nor STAT5 in other cell lines that failed to respond to EPO (ERT cells). EPOR and JAK2 associate with each other regardless of EPO presence in ERT/E2 cells, however, such an interaction is not present in ERT cells. Thus, EPOR and JAK2 association seems to be important for EPO responsiveness in CTLL-2 cells. Images PMID:7781605

  4. IL-4/Stat6 activities correlate with apoptosis and metastasis in colon cancer cells

    SciTech Connect

    Li Benhui; Yang Xianzi; Li Pindong; Yuan Qin; Liu Xiaohong; Yuan Jia; Zhang Wenjie

    2008-05-02

    IL-4-induced Stat6 signaling is active in a variety of cell types and plays a role in cell proliferation/growth and resistance to apoptosis. Using EMSA, we identified differential IL-4/Stat6 activities in colorectal cancer cell lines, HT-29 being active Stat6{sup high} phenotype and Caco-2 being defective Stat6{sup null} phenotype, respectively. Active Stat6{sup high} HT-29 cells exhibited resistance to apoptosis by flowcytometry and aggressive metastasis by Transwell assay compared with defective Stat6{sup null} Caco-2 cells. Comparing one another using RT-PCR, Stat6{sup high} HT-29 cells expressed more mRNA of anti-apoptotic and pro-metastatic genes Survivin, MDM2, and TMPRSS4, while Stat6{sup null} Caco-2 cells expressed more mRNA of pro-apoptotic and anti-metastatic genes BAX, CAV1, and P53, respectively. This is the first study describing correlations of IL-4/Stat6 activities with apoptosis and metastasis in colon cancer. These findings, together with the observation of constitutive Stat6 activation in many human malignancies, suggest that Stat6 activities could be a biomarker for cancer cell's invasive/metastatic capability.

  5. Nifuroxazide inhibits survival of multiple myeloma cells by directly inhibiting STAT3.

    PubMed

    Nelson, Erik A; Walker, Sarah R; Kepich, Alicia; Gashin, Laurie B; Hideshima, Teru; Ikeda, Hiroshi; Chauhan, Dharminder; Anderson, Kenneth C; Frank, David A

    2008-12-15

    Constitutive activation of the transcription factor STAT3 contributes to the pathogenesis of many cancers, including multiple myeloma (MM). Since STAT3 is dispensable in most normal tissue, targeted inhibition of STAT3 is an attractive therapy for patients with these cancers. To identify STAT3 inhibitors, we developed a transcriptionally based assay and screened a library of compounds known to be safe in humans. We found the drug nifuroxazide to be an effective inhibitor of STAT3 function. Nifuroxazide inhibits the constitutive phosphorylation of STAT3 in MM cells by reducing Jak kinase autophosphorylation, and leads to down-regulation of the STAT3 target gene Mcl-1. Nifuroxazide causes a decrease in viability of primary myeloma cells and myeloma cell lines containing STAT3 activation, but not normal peripheral blood mononuclear cells. Although bone marrow stromal cells provide survival signals to myeloma cells, nifuroxazide can overcome this survival advantage. Reflecting the interaction of STAT3 with other cellular pathways, nifuroxazide shows enhanced cytotoxicity when combined with either the histone deacetylase inhibitor depsipeptide or the MEK inhibitor UO126. Therefore, using a mechanistic-based screen, we identified the clinically relevant drug nifuroxazide as a potent inhibitor of STAT signaling that shows cytotoxicity against myeloma cells that depend on STAT3 for survival. PMID:18824601

  6. Nifuroxazide inhibits survival of multiple myeloma cells by directly inhibiting STAT3

    PubMed Central

    Nelson, Erik A.; Walker, Sarah R.; Kepich, Alicia; Gashin, Laurie B.; Hideshima, Teru; Ikeda, Hiroshi; Chauhan, Dharminder; Anderson, Kenneth C.

    2008-01-01

    Constitutive activation of the transcription factor STAT3 contributes to the pathogenesis of many cancers, including multiple myeloma (MM). Since STAT3 is dispensable in most normal tissue, targeted inhibition of STAT3 is an attractive therapy for patients with these cancers. To identify STAT3 inhibitors, we developed a transcriptionally based assay and screened a library of compounds known to be safe in humans. We found the drug nifuroxazide to be an effective inhibitor of STAT3 function. Nifuroxazide inhibits the constitutive phosphorylation of STAT3 in MM cells by reducing Jak kinase autophosphorylation, and leads to down-regulation of the STAT3 target gene Mcl-1. Nifuroxazide causes a decrease in viability of primary myeloma cells and myeloma cell lines containing STAT3 activation, but not normal peripheral blood mononuclear cells. Although bone marrow stromal cells provide survival signals to myeloma cells, nifuroxazide can overcome this survival advantage. Reflecting the interaction of STAT3 with other cellular pathways, nifuroxazide shows enhanced cytotoxicity when combined with either the histone deacetylase inhibitor depsipeptide or the MEK inhibitor UO126. Therefore, using a mechanistic-based screen, we identified the clinically relevant drug nifuroxazide as a potent inhibitor of STAT signaling that shows cytotoxicity against myeloma cells that depend on STAT3 for survival. PMID:18824601

  7. Inborn errors of human STAT1: allelic heterogeneity governs the diversity of immunological and infectious phenotypes

    PubMed Central

    Boisson-Dupuis, Stephanie; Kong, Xiao-Fei; Okada, Satoshi; Cypowyj, Sophie; Puel, Anne; Abel, Laurent; Casanova, Jean-Laurent

    2012-01-01

    The genetic dissection of various human infectious diseases has led to the definition of inborn errors of human STAT1 immunity of four types, including (i) autosomal recessive (AR) complete STAT1 deficiency, (ii) AR partial STAT1 deficiency, (iii) autosomal dominant (AD) STAT1 deficiency, and (iv) AD gain of STAT1 activity. The two types of AR STAT1 defect give rise to a broad infectious phenotype with susceptibility to intramacrophagic bacteria (mostly mycobacteria) and viruses (herpes viruses at least), due principally to the impairment of IFN-γ-mediated and IFN-α/β-mediated immunity, respectively. Clinical outcome depends on the extent to which the STAT1 defect decreases responsiveness to these cytokines. AD STAT1 deficiency selectively predisposes individuals to mycobacterial disease, owing to the impairment of IFN-γ-mediated immunity, as IFN-α/β-mediated immunity is maintained. Finally, AD gain of STAT1 activity is associated with autoimmunity, probably owing to an enhancement of IFN-α/β-mediated immunity. More surprisingly, it is also associated with chronic mucocutaneous candidiasis, through as yet undetermined mechanisms involving an inhibition of the development of IL-17-producing T cells. Thus, germline mutations in human STAT1 define four distinct clinical disorders. Various combinations of viral, mycobacterial and fungal infections are therefore allelic at the human STAT1 locus. These experiments of Nature neatly highlight the clinical and immunological impact of the human genetic dissection of infectious phenotypes. PMID:22651901

  8. The dark and the bright side of Stat3: proto-oncogene and tumor-suppressor.

    PubMed

    Ecker, Andrea; Simma, Olivia; Hoelbl, Andrea; Kenner, Lukas; Beug, Hartmut; Moriggl, Richard; Sexl, Veronika

    2009-01-01

    Stat transcription factors have been implicated in tumorigenesis in mice and men. Stat3 and Stat5 are considered powerful proto-oncogenes, whereas Stat1 has been demonstrated to suppress tumor formation. We demonstrate here for the first time that a constitutive active version of Stat3alpha (Stat3alphaC) may also suppress transformation. Mouse embryonic fibroblasts (MEFs) deficient for p53 can be transformed with either c-myc or with rasV12 alone. Interestingly, transformation by c-myc is efficiently suppressed by co-expression of Stat3alphaC, but Stat3alphaC does not interfere with transformation by the rasV12-oncogene. In contrast, transplantation of bone marrow cells expressing Stat3alphaC induces the formation of a highly aggressive T cell leukemia in mice. The leukemic cells invaded multiple organs including lung, heart, salivary glands, liver and kidney. Interestingly, transplanted mice developed a similar leukemia when the bone marrow cells were transduced with Stat3beta, which is also constitutively active when expressed at significant levels. Our experiments demonstrate that Stat3 has both - tumor suppressing and tumor promoting properties. PMID:19273247

  9. STAT1 Pathway Mediates Amplification of Metastatic Potential and Resistance to Therapy

    PubMed Central

    Pitroda, Sean P.; Golden, Daniel W.; Bhayani, Mihir; Shao, Michael Y.; Darga, Thomas E.; Beveridge, Mara G.; Sood, Ravi F.; Sutton, Harold G.; Beckett, Michael A.; Mauceri, Helena J.; Posner, Mitchell C.; Weichselbaum, Ralph R.

    2009-01-01

    Background Traditionally IFN/STAT1 signaling is connected with an anti-viral response and pro-apoptotic tumor-suppressor functions. Emerging functions of a constitutively activated IFN/STAT1 pathway suggest an association with an aggressive tumor phenotype. We hypothesized that tumor clones that constitutively overexpress this pathway are preferentially selected by the host microenvironment due to a resistance to STAT1-dependent cytotoxicity and demonstrate increased metastatic ability combined with increased resistance to genotoxic stress. Methodology/Principal Findings Here we report that clones of B16F1 tumors grown in the lungs of syngeneic C57BL/6 mice demonstrate variable transcriptional levels of IFN/STAT1 pathway expression. Tumor cells that constitutively overexpress the IFN/STAT1 pathway (STAT1H genotype) are selected by the lung microenvironment. STAT1H tumor cells also demonstrate resistance to IFN-gamma (IFNγ), ionizing radiation (IR), and doxorubicin relative to parental B16F1 and low expressors of the IFN/STAT1 pathway (STAT1L genotype). Stable knockdown of STAT1 reversed the aggressive phenotype and decreased both lung colonization and resistance to genotoxic stress. Conclusions Our results identify a pathway activated by tumor-stromal interactions thereby selecting for pro-metastatic and therapy-resistant tumor clones. New therapies targeted against the IFN/STAT1 signaling pathway may provide an effective strategy to treat or sensitize aggressive tumor clones to conventional cancer therapies and potentially prevent distant organ colonization. PMID:19503789

  10. Transcription Factor STAT3 as a Novel Molecular Target for Cancer Prevention

    PubMed Central

    Xiong, Ailian; Yang, Zhengduo; Shen, Yicheng; Zhou, Jia; Shen, Qiang

    2014-01-01

    Signal Transducers and Activators of Transcription (STATs) are a family of transcription factors that regulate cell proliferation, differentiation, apoptosis, immune and inflammatory responses, and angiogenesis. Cumulative evidence has established that STAT3 has a critical role in the development of multiple cancer types. Because it is constitutively activated during disease progression and metastasis in a variety of cancers, STAT3 has promise as a drug target for cancer therapeutics. Recently, STAT3 was found to have an important role in maintaining cancer stem cells in vitro and in mouse tumor models, suggesting STAT3 is integrally involved in tumor initiation, progression and maintenance. STAT3 has been traditionally considered as nontargetable or undruggable, and the lag in developing effective STAT3 inhibitors contributes to the current lack of FDA-approved STAT3 inhibitors. Recent advances in cancer biology and drug discovery efforts have shed light on targeting STAT3 globally and/or specifically for cancer therapy. In this review, we summarize current literature and discuss the potential importance of STAT3 as a novel target for cancer prevention and of STAT3 inhibitors as effective chemopreventive agents. PMID:24743778

  11. Regulation of STATs by polycystin-1 and their role in polycystic kidney disease

    PubMed Central

    Weimbs, Thomas; Olsan, Erin E.; Talbot, Jeffrey J.

    2013-01-01

    Autosomal-dominant polycystic kidney disease (ADPKD) is a common genetic disease caused by mutations in the gene coding for polycystin-1 (PC1). PC1 can regulate STAT transcription factors by a novel, dual mechanism. STAT3 and STAT6 are aberrantly activated in renal cysts. Genetic and pharmacological approaches to inhibit STAT3 or STAT6 have led to promising results in ADPKD mouse models. Here, we review current findings that lead to a model of PC1 as a key regulator of STAT signaling in renal tubule cells. We discuss how PC1 may orchestrate appropriate epithelial responses to renal injury, and how this system may lead to aberrant STAT activation in ADPKD thereby causing inappropriate activation of tissue repair programs that culminate in renal cyst growth and fibrosis. PMID:24058808

  12. Stat3 is involved in control of MASP2 gene expression

    SciTech Connect

    Unterberger, Claudia; Hanson, Steven; Klingenhoff, Andreas; Oesterle, Daniela; Frankenberger, Marion; Endo, Yuichi; Matsushita, Misao; Fujita, Teizo; Schwaeble, Wilhelm; Weiss, Elisabeth H.; Ziegler-Heitbrock, Loems; Stover, Cordula

    2007-12-28

    Little is known about determinants regulating expression of Mannan-binding lectin associated serine protease-2 (MASP-2), the effector component of the lectin pathway of complement activation. Comparative bioinformatic analysis of the MASP2 promoter regions in human, mouse, and rat, revealed conservation of two putative Stat binding sites, termed StatA and StatB. Site directed mutagenesis specific for these sites was performed. Transcription activity was decreased 5-fold when StatB site was mutated in the wildtype reporter gene construct. Gel retardation and competition assays demonstrated that proteins contained in the nuclear extract prepared from HepG2 specifically bound double-stranded StatB oligonucleotides. Supershift analysis revealed Stat3 to be the major specific binding protein. We conclude that Stat3 binding is important for MASP2 promoter activity.

  13. KAP1 regulates type I interferon/STAT1-mediated IRF-1 gene expression

    SciTech Connect

    Kamitani, Shinya; Ohbayashi, Norihiko; Ikeda, Osamu; Togi, Sumihito; Muromoto, Ryuta; Sekine, Yuichi; Ohta, Kazuhide; Ishiyama, Hironobu; Matsuda, Tadashi

    2008-05-30

    Signal transducers and activators of transcription (STATs) mediate cell proliferation, differentiation, and survival in immune responses, hematopoiesis, neurogenesis, and other biological processes. Recently, we showed that KAP1 is a novel STAT-binding partner that regulates STAT3-mediated transactivation. KAP1 is a universal co-repressor protein for the KRAB zinc finger protein superfamily of transcriptional repressors. In this study, we found KAP1-dependent repression of interferon (IFN)/STAT1-mediated signaling. We also demonstrated that endogenous KAP1 associates with endogenous STAT1 in vivo. Importantly, a small-interfering RNA-mediated reduction in KAP1 expression enhanced IFN-induced STAT1-dependent IRF-1 gene expression. These results indicate that KAP1 may act as an endogenous regulator of the IFN/STAT1 signaling pathway.

  14. Cross-talk between KLF4 and STAT3 regulates axon regeneration

    NASA Astrophysics Data System (ADS)

    Qin, Song; Zou, Yuhua; Zhang, Chun-Li

    2013-10-01

    Cytokine-induced activation of signal transducer and activator of transcription 3 (STAT3) promotes the regrowth of damaged axons in the adult central nervous system (CNS). Here we show that KLF4 physically interacts with STAT3 upon cytokine-induced phosphorylation of tyrosine 705 (Y705) on STAT3. This interaction suppresses STAT3-dependent gene expression by blocking its DNA-binding activity. The deletion of KLF4 in vivo induces axon regeneration of adult retinal ganglion cells (RGCs) via Janus kinase (JAK)-STAT3 signalling. This regeneration can be greatly enhanced by exogenous cytokine treatment, or removal of an endogenous JAK-STAT3 pathway inhibitor called suppressor of cytokine signalling 3 (SOCS3). These findings reveal an unexpected cross-talk between KLF4 and activated STAT3 in the regulation of axon regeneration that might have therapeutic implications in promoting repair of injured adult CNS.

  15. The Role of STAT3 in Non-Small Cell Lung Cancer

    PubMed Central

    Harada, Daijiro; Takigawa, Nagio; Kiura, Katsuyuki

    2014-01-01

    Persistent phosphorylation of signal transducer and activator of transcription 3 (STAT3) has been demonstrated in 22%~65% of non-small cell lung cancers (NSCLC). STAT3 activation is mediated by receptor tyrosine kinases, such as epidermal growth factor receptor (EGFR) and MET, cytokine receptors, such as IL-6, and non-receptor kinases, such as Src. Overexpression of total or phosphorylated STAT3 in resected NSCLC leads to poor prognosis. In a preclinical study, overexpression of STAT3 was correlated with chemoresistance and radioresistance in NSCLC cells. Here, we review the role of STAT3 and the mechanisms of treatment resistance in malignant diseases, especially NSCLC. As STAT3 is a critical mediator of the oncogenic effects of EGFR mutations, we discuss STAT3 pathways in EGFR-mutated NSCLC, referring to mechanisms of EGFR tyrosine kinase inhibitor resistance. PMID:24675568

  16. The Role of STAT3 in Non-Small Cell Lung Cancer.

    PubMed

    Harada, Daijiro; Takigawa, Nagio; Kiura, Katsuyuki

    2014-01-01

    Persistent phosphorylation of signal transducer and activator of transcription 3 (STAT3) has been demonstrated in 22%~65% of non-small cell lung cancers (NSCLC). STAT3 activation is mediated by receptor tyrosine kinases, such as epidermal growth factor receptor (EGFR) and MET, cytokine receptors, such as IL-6, and non-receptor kinases, such as Src. Overexpression of total or phosphorylated STAT3 in resected NSCLC leads to poor prognosis. In a preclinical study, overexpression of STAT3 was correlated with chemoresistance and radioresistance in NSCLC cells. Here, we review the role of STAT3 and the mechanisms of treatment resistance in malignant diseases, especially NSCLC. As STAT3 is a critical mediator of the oncogenic effects of EGFR mutations, we discuss STAT3 pathways in EGFR-mutated NSCLC, referring to mechanisms of EGFR tyrosine kinase inhibitor resistance. PMID:24675568

  17. High Glucose Induces Down-Regulated GRIM-19 Expression to Activate STAT3 Signaling and Promote Cell Proliferation in Cell Culture

    PubMed Central

    Li, Yong-Guang; Han, Bei-Bei; Li, Feng; Yu, Jian-Wu; Dong, Zhi-Feng; Niu, Geng-Ming; Qing, Yan-Wei; Li, Jing-Bo; Wei, Meng; Zhu, Wei

    2016-01-01

    Recent studies indicated that Gene Associated with Retinoid-IFN-Induced Mortality 19 (GRIM-19), a newly discovered mitochondria-related protein, can regulate mitochondrial function and modulate cell viability possibly via interacting with STAT3 signal. In the present study we sought to test: 1) whether GRIM-19 is involved in high glucose (HG) induced altered cell metabolism in both cancer and cardiac cells, 2) whether GRIM-19/STAT3 signaling pathway plays a role in HG induced biological effects, especially whether AMPK activity could be involved. Our data showed that HG enhanced cell proliferation of both HeLa and H9C2 cells, which was closely associated with down-regulated GRIM-19 expression and increased phosphorylated STAT3 level. We showed that GRIM-19 knock-down alone in normal glucose cultured cells can also result in an increase in phosphorylated STAT3 level and enhanced proliferation capability, whereas GRIM-19 over-expression can abolished HG induced STAT3 activation and enhanced cell proliferation. Importantly, both down-regulated or over-expression of GRIM-19 increased lactate production in both HeLa and H9C2 cells. The activated STAT3 was responsible for increased cell proliferation as either AG-490, an inhibitor of JAK2, or siRNA targeting STAT3 can attenuate cell proliferation increased by HG. In addition, HG increased lactate acid levels in HeLa cells, which was also observed when GRIM-19 was genetically manipulated. However, HG did not affect the lactate levels in H9C2 cells. Of note, over-expression of GRIM-19 and silencing of STAT3 both increased lactate production in H9C2 cells. As expected, HG resulted in significant decreases in phosphorylated AMPKα levels in H9C2 cells, but not in HeLa cells. Interestingy, activation of AMPKα by metformin was associated with a reversal of the suppressed GRIM-19 expression in H9C2 cells, the fold of changes in GRIM-19 expression by metformin were much less in HeLa cells. Metformin did not affect the

  18. HIV-1-infected and immune-activated macrophages induce astrocytic differentiation of human cortical neural progenitor cells via the STAT3 pathway.

    PubMed

    Peng, Hui; Sun, Lijun; Jia, Beibei; Lan, Xiqian; Zhu, Bing; Wu, Yumei; Zheng, Jialin

    2011-01-01

    Diminished adult neurogenesis is considered a potential mechanism in the pathogenesis of HIV-1-associated dementia (HAD). In HAD, HIV-1-infected and immune-activated brain mononuclear phagocytes (MP; perivascular macrophages and microglia) drive central nervous system (CNS) inflammation and may alter normal neurogenesis. We previously demonstrated HIV-1-infected and lipopolysaccharide (LPS) activated monocyte-derived macrophages (MDM) inhibit human neural progenitor cell (NPC) neurogenesis, while enhancing astrogliogenesis through the secretion of the inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), in vitro and in vivo. Here we further test the hypothesis that HIV-1-infected/activated MDM promote NPC astrogliogenesis via activation of the transcription factor signal transducer and activator of transcription 3 (STAT3), a critical factor for astrogliogenesis. Our results show that LPS-activated MDM-conditioned medium (LPS-MCM) and HIV-infected/LPS-activated MDM-conditioned medium (LPS+HIV-MCM) induced Janus kinase 1 (Jak1) and STAT3 activation. Induction of the Jak-STAT3 activation correlated with increased glia fibrillary acidic protein (GFAP) expression, demonstrating an induction of astrogliogenesis. Moreover, STAT3-targeting siRNA (siSTAT3) decreased MCM-induced STAT3 activation and NPC astrogliogenesis. Furthermore, inflammatory cytokines (including IL-6, IL-1β and TNF-α) produced by LPS-activated and/or HIV-1-infected MDM may contribute to MCM-induced STAT3 activation and astrocytic differentiation. These observations were confirmed in severe combined immunodeficient (SCID) mice with HIV-1 encephalitis (HIVE). In HIVE mice, siRNA control (without target sequence, sicon) pre-transfected NPCs injected with HIV-1-infected MDM showed more astrocytic differentiation and less neuronal differentiation of NPCs as compared to NPC injection alone. siSTAT3 abrogated HIV-1-infected MDM-induced astrogliogenesis of injected NPCs. Collectively, these

  19. Overcoming Chemoresistance of Pediatric Ependymoma by Inhibition of STAT3 Signaling.

    PubMed

    Phi, Ji Hoon; Choi, Seung-Ah; Kim, Seung-Ki; Wang, Kyu-Chang; Lee, Ji Yeoun; Kim, Dong Gyu

    2015-10-01

    The long-term clinical outcome of pediatric intracranial epepdymoma is poor with a high rate of recurrence. One of the main reasons for this poor outcome is the tumor's inherent resistance to chemotherapy. Signal transducer and activator of transcription 3 (STAT3) is overactive in many human cancers, and inhibition of STAT3 signaling is an emerging area of interest in oncology. In this study, the possibility of STAT3 inhibition as a treatment was investigated in pediatric intracranial ependymoma tissues and cell lines. STAT3 activation status was checked in ependymoma tissues. The responses to conventional chemotherapeutic agents and a STAT3 inhibitor WP1066 in primarily cultured ependymoma cells were measured by cell viability assay. Apoptosis assays were conducted to reveal the cytotoxic mechanism of applied agents. Knockdown of STAT3 was tried to confirm the effects of STAT3 inhibition in ependymoma cells. High levels of phospho-STAT3 (p-STAT3) expression were observed in ependymoma tissue, especially in the anaplastic histology group. There was no cytotoxic effect of cisplatin, ifosfamide, and etoposide. Both brain tumor-initiating cells (BTICs) and bulk tumor cells (BCs) showed considerably decreased viability after WP1066 treatment. However, BTICs had fewer responses than BCs. No additive or synergistic effect was observed for combination therapy of WP1066 and cisplatin. WP1066 effectively abrogated p-STAT3 expression. An increased apoptosis and decreased Survivin expression were observed after WP1066 treatment. Knockdown of STAT3 also decreased cell survival, supporting the critical role of STAT3 in sustaining ependymoma cells. In this study, we observed a cytotoxic effect of STAT3 inhibitor on ependymoma BTICs and BCs. There is urgent need to develop new therapeutic agents for pediatric ependymoma. STAT3 inhibitors may be a new group of drugs for clinical application. PMID:26500028

  20. Suppression of autophagy augments the radiosensitizing effects of STAT3 inhibition on human glioma cells

    SciTech Connect

    Yuan, Xiaopeng; Du, Jie; Hua, Song; Zhang, Haowen; Gu, Cheng; Wang, Jie; Yang, Lei; Huang, Jianfeng; Yu, Jiahua Liu, Fenju

    2015-01-15

    Radiotherapy is an essential component of the standard therapy for newly diagnosed glioblastoma. To increase the radiosensitivity of glioma cells is a feasible solution to improve the therapeutic effects. It has been suggested that inhibition of signal transducer and activator of transcription 3 (STAT3) can radiosensitize glioma cells, probably via the activation of mitochondrial apoptotic pathway. In this study, human malignant glioma cells, U251 and A172, were treated with an STAT3 inhibitor, WP1066, or a short hairpin RNA plasmid targeting STAT3 to suppress the activation of STAT3 signaling. The radiosensitizing effects of STAT3 inhibition were confirmed in glioma cells. Intriguingly, combination of ionizing radiation exposure and STAT3 inhibition triggered a pronounced increase of autophagy flux. To explore the role of autophagy, glioma cells were treated with 3-methyladenine or siRNA for autophagy-related gene 5, and it was demonstrated that inhibition of autophagy further strengthened the radiosensitizing effects of STAT3 inhibition. Accordingly, more apoptotic cells were induced by the dual inhibition of autophagy and STAT3 signaling. In conclusion, our data revealed a protective role of autophagy in the radiosensitizing effects of STAT3 inhibition, and inhibition of both autophagy and STAT3 might be a potential therapeutic strategy to increase the radiosensitivity of glioma cells. - Highlights: • Inactivation of STAT3 signaling radiosensitizes malignant glioma cells. • STAT3 inhibition triggers a significant increase of autophagy flux induced by ionizing radiation in glioma cells. • Suppression of autophagy further strengthens the radiosensitizing effects of STAT3 inhibition in glioma cells. • Dual inhibition of autophagy and STAT3 induce massive apoptotic cells upon exposure to ionizing radiation.

  1. STAT2 Is Required for TLR-Induced Murine Dendritic Cell Activation and Cross-Presentation.

    PubMed

    Xu, Jun; Lee, Michael H; Chakhtoura, Marita; Green, Benjamin L; Kotredes, Kevin P; Chain, Robert W; Sriram, Uma; Gamero, Ana M; Gallucci, Stefania

    2016-07-01

    TLR-stimulated cross-presentation by conventional dendritic cells (cDCs) is important in host defense and antitumor immunity. We recently reported that cDCs lacking the type I IFN signaling molecule STAT2 are impaired in cross-presenting tumor Ags to CD8(+) T cells. To investigate how STAT2 affects cross-presentation, we determined its requirements for dendritic cell activation. In this study, we report that STAT2 is essential for the activation of murine female cDCs upon TLR3, -4, -7, and -9 stimulation. In response to various TLR ligands, Stat2(-/-) cDCs displayed reduced expression of costimulatory molecules and type I IFN-stimulated genes. The cDC responses to exogenous IFN-α that we evaluated required STAT2 activation, indicating that the canonical STAT1-STAT2 heterodimers are the primary signaling transducers of type I IFNs in cDCs. Interestingly, LPS-induced production of IL-12 was STAT2 and type I IFN receptor (IFNAR) dependent, whereas LPS-induced production of TNF-α and IL-6 was STAT2 and IFNAR independent, suggesting a specific role of the IFNAR-STAT2 axis in the stimulation of proinflammatory cytokines by LPS in cDCs. In contrast, R848- and CpG-induced cytokine production was less influenced by the IFNAR-STAT2 axis. Short kinetics and IFNAR blockade studies showed that STAT2 main function is to transduce signals triggered by autocrine type I IFNs. Importantly, Stat2(-/-) cDCs were deficient in cross-presenting to CD8(+) T cells in vitro upon IFN-α, CpG, and LPS stimulation, and also in cross-priming and licensing cytotoxic T cell killers in vivo. We conclude that STAT2 plays a critical role in TLR-induced dendritic cell activation and cross-presentation, and thus is vital in host defense. PMID:27233962

  2. Intersection of mTOR and STAT signaling in immunity

    PubMed Central

    Saleiro, Diana; Platanias, Leonidas C.

    2014-01-01

    Optimal regulation of immune networks is essential for generation of effective immune responses, and defects in such networks can lead to immunodeficiency, while uncontrolled responses can result in autoimmune disorders. mTOR and STAT signaling cascades are key regulators of differentiation and function of cells of the immune system. Both pathways act as sensors and transducers of environmental stimuli, and recent evidence has revealed points of crosstalk between these pathways, highlighting synergistic regulation of immune cell differentiation and function. Here we review the current understanding of mTOR and STAT interactions in T cells and innate immune cells, and discuss potential mechanisms underlying these events. We further outline models for the intersection of these pathways in the regulation of immunity, and highlight important areas for future research. PMID:25592035

  3. Activating STAT3 Alpha for Promoting Healing of Neurons

    NASA Technical Reports Server (NTRS)

    Conway, Greg

    2008-01-01

    A method of promoting healing of injured or diseased neurons involves pharmacological activation of the STAT3 alpha protein. Usually, injured or diseased neurons heal incompletely or not at all for two reasons: (1) they are susceptible to apoptosis (cell death); and (2) they fail to engage in axogenesis that is, they fail to re-extend their axons to their original targets (e.g., muscles or other neurons) because of insufficiency of compounds, denoted neurotrophic factors, needed to stimulate such extension. The present method (see figure) of treatment takes advantage of prior research findings to the effect that the STAT3 alpha protein has anti-apoptotic and pro-axogenic properties.

  4. STAT3: A Novel Molecular Mediator of Resistance to Chemoradiotherapy

    PubMed Central

    Spitzner, Melanie; Ebner, Reinhard; Wolff, Hendrik A.; Ghadimi, B. Michael; Wienands, Jürgen; Grade, Marian

    2014-01-01

    Chemoradiotherapy (CRT) represents a standard treatment for many human cancers, frequently combined with radical surgical resection. However, a considerable percentage of primary cancers are at least partially resistant to CRT, which represents a substantial clinical problem, because it exposes cancer patients to the potential side effects of both irradiation and chemotherapy. It is therefore exceedingly important to determine the molecular characteristics underlying CRT-resistance and to identify novel molecular targets that can be manipulated to re-sensitize resistant tumors to CRT. In this review, we highlight much of the recent evidence suggesting that the signal transducer and activator of transcription 3 (STAT3) plays a prominent role in mediating CRT-resistance, and we outline why inhibition of STAT3 holds great promise for future multimodal treatment concepts in oncology. PMID:25268165

  5. Biology and significance of the JAK/STAT signalling pathways

    PubMed Central

    Kiu, Hiu; Nicholson, Sandra E

    2013-01-01

    Since its discovery two decades ago, the activation of the JAK/STAT pathway by numerous cytokines and growth factors has resulted in it becoming one of the most well studied intracellular signalling networks. The field has progressed from the identification of the individual components, to high-resolution crystal structures of both JAK and STAT, and an understanding of the complexities of the molecular activation and deactivation cycle which results in a diverse, yet highly specific and regulated pattern of transcriptional responses. While there is still more to learn, we now appreciate how disruption and de-regulation of this pathway can result in clinical disease and look forward to adoption of the next generation of JAK inhibitors in routine clinical treatment. PMID:22339650

  6. Constitutive STAT5 Activation Correlates With Better Survival in Cervical Cancer Patients Treated With Radiation Therapy

    SciTech Connect

    Chen, Helen H.W.; Chou, Cheng-Yang; Wu, Yuan-Hua; Hsueh, Wei-Ting; Hsu, Chiung-Hui; Guo, How-Ran; Lee, Wen-Ying; Su, Wu-Chou

    2012-02-01

    Purpose: Constitutively activated signal transducers and activators of transcription (STAT) factors, in particular STAT1, STAT3, and STAT5, have been detected in a wide variety of human primary tumors and have been demonstrated to directly contribute to oncogenesis. However, the expression pattern of these STATs in cervical carcinoma is still unknown, as is whether or not they have prognostic significance. This study investigated the expression patterns of STAT1, STAT3, and STAT5 in cervical cancer and their associations with clinical outcomes in patients treated with radical radiation therapy. Methods and Materials: A total of 165 consecutive patients with International Federation of Gynecology and Obstetrics (FIGO) Stages IB to IVA cervical cancer underwent radical radiation therapy, including external beam and/or high-dose-rate brachytherapy between 1989 and 2002. Immunohistochemical studies of their formalin-fixed, paraffin-embedded tissues were performed. Univariate and multivariate analyses were performed to identify and to evaluate the effects of these factors affecting patient survival. Results: Constitutive activations of STAT1, STAT3, and STAT5 were observed in 11%, 22%, and 61% of the participants, respectively. While STAT5 activation was associated with significantly better metastasis-free survival (p < 0.01) and overall survival (p = 0.04), STAT1 and STAT3 activation were not. Multivariate analyses showed that STAT5 activation, bulky tumor ({>=}4 cm), advanced stage (FIGO Stages III and IV), and brachytherapy (yes vs. no) were independent prognostic factors for cause-specific overall survival. None of the STATs was associated with local relapse. STAT5 activation (odds ratio = 0.29, 95% confidence interval = 0.13-0.63) and advanced stage (odds ratio = 2.54; 95% confidence interval = 1.03-6.26) were independent predictors of distant metastasis. Conclusions: This is the first report to provide the overall expression patterns and prognostic significance of

  7. Interleukin-4-induced transcriptional activation by stat6 involves multiple serine/threonine kinase pathways and serine phosphorylation of stat6.

    PubMed

    Pesu, M; Takaluoma, K; Aittomäki, S; Lagerstedt, A; Saksela, K; Kovanen, P E; Silvennoinen, O

    2000-01-15

    Stat6 transcription factor is a critical mediator of IL-4-specific gene responses. Tyrosine phosphorylation is required for nuclear localization and DNA binding of Stat6. The authors investigated whether Stat6-dependent transcriptional responses are regulated through IL-4-induced serine/threonine phosphorylation. In Ramos B cells, the serine/threonine kinase inhibitor H7 inhibited IL-4-induced expression of CD23. Treatment with H7 did not affect IL-4R-mediated immediate signaling events such as tyrosine phosphorylation of Jak1, Jak3, insulin receptor substrate (IRS)-1 and IRS-2, or tyrosine phosphorylation and DNA binding of Stat6. To analyze whether the H7-sensitive pathway was regulating Stat6-activated transcription, we used reporter constructs containing different IL-4 responsive elements. H7 abrogated Stat6-, as well as Stat5-, mediated reporter gene activation and partially reduced C/EBP-dependent reporter activity. By contrast, IL-4-induced transcription was not affected by wortmannin, an inhibitor of the phosphatidyl-inositol 3'-kinase pathway. Phospho-amino acid analysis and tryptic phosphopeptide maps revealed that IL-4 induced phosphorylation of Stat6 on serine and tyrosine residues in Ramos cells and in 32D cells lacking endogenous IRS proteins. However, H7 treatment did not inhibit the phosphorylation of Stat6. Instead, H7 inhibited the IL-4-induced phosphorylation of RNA polymerase II. These results indicate that Stat6-induced transcription is dependent on phosphorylation events mediated by H7-sensitive kinase(s) but that it also involves serine phosphorylation of Stat6 by an H7-insensitive kinase independent of the IRS pathway. (Blood. 2000;95:494-502) PMID:10627454

  8. IL-6/STAT3 axis initiated CAFs via up-regulating TIMP-1 which was attenuated by acetylation of STAT3 induced by PCAF in HCC microenvironment.

    PubMed

    Zheng, Xin; Xu, Meng; Yao, Bowen; Wang, Cong; Jia, Yuli; Liu, Qingguang

    2016-09-01

    Aberrant tumor microenvironment is involved closely in tumor initiation and progression, in which cancer associated fibroblasts (CAFs) play a pivotal role. Both IL-6/STAT3 signaling and TIMP-1 have been found to modulate the crosstalk between tumor cells and CAFs in tumor microenvironment, however, the underlying mechanism remains unclear. Here, we showed that IL-6/STAT3 signaling was activated aberrantly in HCC tissues and correlated with poor post-surgical outcome. The in vitro experiments confirmed that activation of IL-6/STAT3 pathway enhanced TIMP-1 expression directly via phosphorylated STATs (p-STAT3)-binding with TIMP-1 promoter in Huh7 cells. Furthermore, activation of IL-6/STAT3 pathway in HCC cells was shown to induce the transformation from normal liver fibroblasts (LFs) to CAFs via up-regulating TIMP-1 expression. Co-culture with CAFs promoted the growth of Huh7 cells both in vitro and in vivo. Finally, by co-Immunoprecipitation and immunoblotting assessments, PCAF, a well-known acetyltransferase, was revealed to acetylate cytoplasmic STAT3 protein directly and regulate TIMP-1 expression negatively in Huh7 cells. In summary, this investigation indicated that there was a positive IL-6/TIMP-1 feedback loop controlling the crosstalk between HCC cells and its neighbouring fibroblasts. The data here also identified that PCAF repressed TIMP-1 expression via acetylation of STAT3. In conclusion, this investigation demonstrated that CAFs promoted HCC growth via IL-6/STAT3/AKT pathway and TIMP-1 over-expression driven by IL-6/STAT3 pathway in HCC cells brought in more CAFs through activating LFs. Finally, PCAF could block this positive feedback by acetylating STAT3 in HCC cells. PMID:27297362

  9. A zebrafish intelectin ortholog agglutinates both Gram-negative and Gram-positive bacteria with binding capacity to bacterial polysaccharide.

    PubMed

    Chen, Lei; Yan, Jie; Sun, Weiping; Zhang, Yan; Sui, Chao; Qi, Jing; Du, Yijun; Feng, Lijun

    2016-08-01

    Intelectins are glycan-binding lectins found in various species including cephalochordates, urochordates, fish, amphibians and mammals. But their detailed functions are not well studied in zebrafish which is a good model to study native immunity. In this study, we cloned a zebrafish intelectin ortholog, zebrafish intelectin 2 (zITLN2), which contains a conserved fibrinogen-related domain (FReD) in the N-terminus and the unique intelectin domain in the C-terminus. We examined the tissue distribution of zITLN2 in adult zebrafish and found that zITLN2 was expressed in various organs with the highest level in intestine. Like amphioxus intelectins, zITLN2 expression was upregulated in adult zebrafish infected with Staphylococcus aureus with the highest expression level at 12 h after challenge. Recombinant zITLN2 protein expressed in E. coli was able to agglutinate both Gram-negative and Gram-positive bacteria to similar degrees in a calcium-dependent manner. Furthermore, recombinant zITLN2 bound lipopolysaccharide (LPS) and peptidoglycan (PGN) comparably. Our work on zITLN2 provided further information to understand functions of this new family of lectins and the innate immunity in vertebrates. PMID:27329687

  10. Automatic electrochemical micro-pH-stat for biomicrosystems.

    PubMed

    Morimoto, Katsuya; Toya, Mariko; Fukuda, Junji; Suzuki, Hiroaki

    2008-02-15

    A microelectrochemical pH-stat with an automatic feedback function was fabricated. The operation of the device is based on the nonstandard use of an electrochemical three-electrode system with a pH-sensitive reference electrode, a Ag/AgCl working electrode, and an iridium auxiliary electrode that functions as an actuator to adjust the solution pH. The combination of the electrodes caused a negative feedback in response to a pH change. The shift of the potential of the pH-sensitive reference electrode caused an overpotential on the Ag/AgCl working electrode, which then caused a significant current increase. This led to the electrolysis of water on the auxiliary electrode and the rapid recovery of the pH. The negative feedback function to stabilize the initial state could be confirmed for changes to both the acidic and basic directions. The performance of the pH-stat was characterized in the titration of acetic acid or ammonia. The charge generated in the feedback process changed linearly with respect to the concentration. The pH-stat was also used in the determination of urea by urease and that of the activities of trypsin and pepsin while maintaining the optimum pH for the enzymes. The pH to be fixed could be changed by changing the working electrode potential. Moreover, the two pH-stats could be used to form a pH gradient in a microflow channel by fixing the pH values at two positions. PMID:18186613

  11. Deubiquitinase USP2a Sustains Interferons Antiviral Activity by Restricting Ubiquitination of Activated STAT1 in the Nucleus

    PubMed Central

    Liu, Jin; Yuan, Yukang; Cheng, Qiao; Zuo, Yibo; Qian, Liping; Guo, Tingting; Qian, Guanghui; Li, Lemin; Ge, Jun; Dai, Jianfeng; Xiong, Sidong; Zheng, Hui

    2016-01-01

    STAT1 is a critical transcription factor for regulating host antiviral defenses. STAT1 activation is largely dependent on phosphorylation at tyrosine 701 site of STAT1 (pY701-STAT1). Understanding how pY701-STAT1 is regulated by intracellular signaling remains a major challenge. Here we find that pY701-STAT1 is the major form of ubiquitinated-STAT1 induced by interferons (IFNs). While total STAT1 remains relatively stable during the early stages of IFNs signaling, pY701-STAT1 can be rapidly downregulated by the ubiquitin-proteasome system. Moreover, ubiquitinated pY701-STAT1 is located predominantly in the nucleus, and inhibiting nuclear import of pY701-STAT1 significantly blocks ubiquitination and downregulation of pY701-STAT1. Furthermore, we reveal that the deubiquitinase USP2a translocates into the nucleus and binds to pY701-STAT1, and inhibits K48-linked ubiquitination and degradation of pY701-STAT1. Importantly, USP2a sustains IFNs-induced pY701-STAT1 levels, and enhances all three classes of IFNs- mediated signaling and antiviral activity. To our knowledge, this is the first identified deubiquitinase that targets activated pY701-STAT1. These findings uncover a positive mechanism by which IFNs execute efficient antiviral signaling and function, and may provide potential targets for improving IFNs-based antiviral therapy. PMID:27434509

  12. StatsCasts: screencasts for complementing lectures in statistics classes

    NASA Astrophysics Data System (ADS)

    Dunn, Peter K.; McDonald, Christine; Loch, Birgit

    2015-05-01

    Students who are studying introductory statistics units but are enrolled in non-statistics majors often struggle with the content, and do not stay engaged. Support structures are in place at many Australian universities to help these students. Most of these are face-to-face support centres that the students can visit during opening hours. To provide additional assistance to these students any time, and from anywhere, online media are increasingly used by students - either provided by support centres, or sought independently by students. Little research has been undertaken on the effectiveness of such resources to support student learning. This paper investigates whether students will embrace StatsCasts - short screen-capture videos on key statistical topics that students have struggled with in the past, with narrator explanation provided by the lecturer - as part of their learning strategy and if they will actively engage with the videos. Students enrolled in a large first-year statistics class at an Australian university who had been provided with StatsCasts responded to a survey at the end of the semester. Volunteering students also participated in a focus group to probe deeper into students' perceptions of and motivations for watching the videos. Analysis of the data shows that students do actively engage with the StatsCasts and they appear to become an important component of their study and revision strategy.

  13. IL-17 induces EMT via Stat3 in lung adenocarcinoma

    PubMed Central

    Huang, Qi; Han, Jieli; Fan, Jinshuo; Duan, Limin; Guo, Mengfei; Lv, Zhilei; Hu, Guorong; Chen, Lian; Wu, Feng; Tao, Xiaonan; Xu, Juanjuan; Jin, Yang

    2016-01-01

    Epithelial-mesenchymal transition (EMT) plays a vital role in lung inflammatory diseases, including lung cancer. However, the role and mechanism of action of the proinflammatory cytokine IL-17 in EMT in lung adenocarcinoma remain unresolved. In our study, we discovered that the expression of N-cadherin, Vimentin, Snail1, Snail2, and Twist1 was positively correlated with IL-17 expression, while E-cadherin expression was negatively correlated with IL-17 expression in human lung adenocarcinoma tissues. Moreover, we confirmed that IL-17 promoted EMT in A549 and Lewis lung carcinoma (LLC) cells in vitro by upregulating N-cadherin, Vimentin, Snail1, Snail2, and Twist1 expression and downregulating E-cadherin expression. Stat3 was activated in IL-17-treated A549 and LLC cells, and Stat3 inhibition or siRNA knockdown notably reduced IL-17-induced EMT in A549 and LLC cells. Thus, IL-17 promotes EMT in lung adenocarcinoma via Stat3 signaling; these observations suggest that targeting IL-17 and EMT are potential novel therapeutic strategies for lung cancer. PMID:27186414

  14. Reagentless pH-stat for microliter fluid specimens.

    PubMed

    Kao, Linus T-H; Hsu, Hung-Yi; Gratzl, Miklós

    2008-06-01

    pH-stating is a common technique for monitoring kinetics of various biochemical reactions that involve the generation of hydrogen or hydroxyl ions. In this work, we describe a reagentless electrochemical micro-pH-stat where the titrant of acid or base is produced by water electrolysis on the rotating sample system (RSS) platform. RSS originated from the authors' laboratory as a convective platform to support different analytical techniques in microliter-sized samples. As water electrolysis induces no volume change and the current that generates the reagent can be precisely measured even at low levels, very small samples in the microliter range become accessible for pH-stating: a reduction of more than an order of magnitude in specimen size relative to the most sensitive conventional methods. Nearly 100% current efficiency has been achieved with this system using a 250 microm Pt minidisc working electrode for electrolysis. The developed micro-pH-stat has been validated by the determination of the activity of erythrocyte acetylcholinesterase as a function of substrate concentration and pH. The optimal pH and activity profile obtained are in good agreement with those determined with standard techniques. The micro-pH-stat has the potential for applications for enzyme assays, reagentless pH control, acidity/alkalinity, and buffer capacity measurements in very small samples of biomedical and environmental origin. PMID:18442265

  15. Rapid Effects of a Protective O-Polysaccharide-Specific Monoclonal IgA on Vibrio cholerae Agglutination, Motility, and Surface Morphology

    PubMed Central

    Levinson, Kara J.; De Jesus, Magdia

    2015-01-01

    2D6 is a dimeric monoclonal immunoglobulin A (IgA) specific for the nonreducing terminal residue of Ogawa O-polysaccharide (OPS) of Vibrio cholerae. It was previously demonstrated that 2D6 IgA is sufficient to passively protect suckling mice from oral challenge with virulent V. cholerae O395. In this study, we sought to define the mechanism by which 2D6 IgA antibody protects the intestinal epithelium from V. cholerae infection. In a mouse ligated-ileal-loop assay, 2D6 IgA promoted V. cholerae agglutination in the intestinal lumen and limited the ability of the bacteria to associate with the epithelium, particularly within the crypt regions. In vitro fluorescence digital video microscopy analysis of antibody-treated V. cholerae in liquid medium revealed that 2D6 IgA not only induced the rapid (5- to 10-min) onset of agglutination but was an equally potent inhibitor of bacterial motility. Scanning electron microscopy showed that 2D6 IgA promoted flagellum-flagellum cross-linking, as well as flagellar entanglement with bacterial bodies, suggesting that motility arrest may be a consequence of flagellar tethering. However, monovalent 2D6 Fab fragments also inhibited V. cholerae motility, demonstrating that antibody-mediated agglutination and motility arrest are separate phenomena. While 2D6 IgA is neither bactericidal nor bacteriostatic, exposure of V. cholerae to 2D6 IgA (or Fab fragments) resulted in a 5-fold increase in surface-associated blebs, as well an onset of a wrinkled surface morphotype. We propose that the protective immunity conferred by 2D6 IgA is the result of multifactorial effects on V. cholerae, including agglutination, motility arrest, and possibly outer membrane stress. PMID:25667263

  16. The Rabies Virus Interferon Antagonist P Protein Interacts with Activated STAT3 and Inhibits Gp130 Receptor Signaling

    PubMed Central

    Lieu, Kim G.; Brice, Aaron; Wiltzer, Linda; Hirst, Bevan; Jans, David A.; Blondel, Danielle

    2013-01-01

    Immune evasion by rabies virus depends on targeting of the signal transducers and activator of transcription 1 (STAT1) and STAT2 proteins by the viral interferon antagonist P protein, but targeting of other STAT proteins has not been investigated. Here, we find that P protein associates with activated STAT3 and inhibits STAT3 nuclear accumulation and Gp130-dependent signaling. This is the first report of STAT3 targeting by the interferon antagonist of a virus other than a paramyxovirus, indicating that STAT3 antagonism is important to a range of human-pathogenic viruses. PMID:23698294

  17. Involvement of transcription factor Oct-1 in the regulation of JAK-STAT signaling pathway in cells of Burkitt lymphoma.

    PubMed

    Pankratova, E V; Stepchenko, A G; Krylova, I D; Portseva, T N; Georgieva, S G

    2016-05-01

    We studied the role of transcription factor Oct-1 in the regulation of expression of genes of the JAK-STAT signaling pathway in the Namalwa Burkitt's lymphoma cell line. Overexpression of Oct-1 isoforms (Oct-1A, Oct-1L, and Oct-1X) causes a decrease in the activity of four genes involved in the JAK-STAT signaling pathway-IFNAR2, STAT1, STAT2, and STAT4. As a result of our research, it was found that genes STAT2 and STAT4 are direct targets for Oct-1 protein. PMID:27417729

  18. Lab-on-a-disc agglutination assay for protein detection by optomagnetic readout and optical imaging using nano- and micro-sized magnetic beads.

    PubMed

    Uddin, Rokon; Burger, Robert; Donolato, Marco; Fock, Jeppe; Creagh, Michael; Hansen, Mikkel Fougt; Boisen, Anja

    2016-11-15

    We present a biosensing platform for the detection of proteins based on agglutination of aptamer coated magnetic nano- or microbeads. The assay, from sample to answer, is integrated on an automated, low-cost microfluidic disc platform. This ensures fast and reliable results due to a minimum of manual steps involved. The detection of the target protein was achieved in two ways: (1) optomagnetic readout using magnetic nanobeads (MNBs); (2) optical imaging using magnetic microbeads (MMBs). The optomagnetic readout of agglutination is based on optical measurement of the dynamics of MNB aggregates whereas the imaging method is based on direct visualization and quantification of the average size of MMB aggregates. By enhancing magnetic particle agglutination via application of strong magnetic field pulses, we obtained identical limits of detection of 25pM with the same sample-to-answer time (15min 30s) using the two differently sized beads for the two detection methods. In both cases a sample volume of only 10µl is required. The demonstrated automation, low sample-to-answer time and portability of both detection instruments as well as integration of the assay on a low-cost disc are important steps for the implementation of these as portable tools in an out-of-lab setting. PMID:27183287

  19. Agglutinating mouse IgG3 compares favourably with IgMs in typing of the blood group B antigen: Functionality and stability studies.

    PubMed

    Klaus, Tomasz; Bzowska, Monika; Kulesza, Małgorzata; Kabat, Agnieszka Martyna; Jemioła-Rzemińska, Małgorzata; Czaplicki, Dominik; Makuch, Krzysztof; Jucha, Jarosław; Karabasz, Alicja; Bereta, Joanna

    2016-01-01

    Mouse immunoglobulins M (IgMs) that recognize human blood group antigens induce haemagglutination and are used worldwide for diagnostic blood typing. Contrary to the current belief that IgGs are too small to simultaneously bind antigens on two different erythrocytes, we obtained agglutinating mouse IgG3 that recognized antigen B of the human ABO blood group system. Mouse IgG3 is an intriguing isotype that has the ability to form Fc-dependent oligomers. However, F(ab')2 fragments of the IgG3 were sufficient to agglutinate type B red blood cells; therefore, IgG3-triggered agglutination did not require oligomerization. Molecular modelling indicated that mouse IgG3 has a larger range of Fab arms than other mouse IgG subclasses and that the unique properties of mouse IgG3 are likely due to the structure of its hinge region. With a focus on applications in diagnostics, we compared the stability of IgG3 and two IgMs in formulated blood typing reagents using an accelerated storage approach and differential scanning calorimetry. IgG3 was much more stable than IgMs. Interestingly, the rapid decrease in IgM activity was caused by aggregation of the molecules and a previously unknown posttranslational proteolytic processing of the μ heavy chain. Our data point to mouse IgG3 as a potent diagnostic tool. PMID:27484487

  20. Agglutinating mouse IgG3 compares favourably with IgMs in typing of the blood group B antigen: Functionality and stability studies

    PubMed Central

    Klaus, Tomasz; Bzowska, Monika; Kulesza, Małgorzata; Kabat, Agnieszka Martyna; Jemioła-Rzemińska, Małgorzata; Czaplicki, Dominik; Makuch, Krzysztof; Jucha, Jarosław; Karabasz, Alicja; Bereta, Joanna

    2016-01-01

    Mouse immunoglobulins M (IgMs) that recognize human blood group antigens induce haemagglutination and are used worldwide for diagnostic blood typing. Contrary to the current belief that IgGs are too small to simultaneously bind antigens on two different erythrocytes, we obtained agglutinating mouse IgG3 that recognized antigen B of the human ABO blood group system. Mouse IgG3 is an intriguing isotype that has the ability to form Fc-dependent oligomers. However, F(ab′)2 fragments of the IgG3 were sufficient to agglutinate type B red blood cells; therefore, IgG3-triggered agglutination did not require oligomerization. Molecular modelling indicated that mouse IgG3 has a larger range of Fab arms than other mouse IgG subclasses and that the unique properties of mouse IgG3 are likely due to the structure of its hinge region. With a focus on applications in diagnostics, we compared the stability of IgG3 and two IgMs in formulated blood typing reagents using an accelerated storage approach and differential scanning calorimetry. IgG3 was much more stable than IgMs. Interestingly, the rapid decrease in IgM activity was caused by aggregation of the molecules and a previously unknown posttranslational proteolytic processing of the μ heavy chain. Our data point to mouse IgG3 as a potent diagnostic tool. PMID:27484487

  1. STAT3 inhibition suppresses proliferation of retinoblastoma through down-regulation of positive feedback loop of STAT3/miR-17-92 clusters

    PubMed Central

    Jo, Dong Hyun; Kim, Jin Hyoung; Cho, Chang Sik; Cho, Young-Lai; Jun, Hyoung Oh; Yu, Young Suk; Min, Jeong-Ki; Kim, Jeong Hun

    2014-01-01

    Retinoblastoma, the most common intraocular malignant tumor in children, is characterized by the loss of both functional alleles of RB1 gene, which however alone cannot maintain malignant characteristics of retinoblastoma cells. Nevertheless, the investigation of other molecular aberrations such as matrix metalloproteinases (MMPs) and miRNAs is still lacking. In this study, we demonstrate that STAT3 is activated in retinoblastoma cells, Ki67-positive areas of in vivo orthotopic tumors in BALB/c nude mice, and human retinoblastoma tissues of the advanced stage. Furthermore, target genes of STAT3 including BCL2, BCL2L1, BIRC5, and MMP9 are up-regulated in retinoblastoma cells compared to other retinal constituent cells. Interestingly, STAT3 inhibition by targeted siRNA suppresses the proliferation of retinoblastoma cells and the formation of in vivo orthotopic tumors. In line with these results, STAT3 siRNA effectively induces down-regulation of target genes of STAT3. In addition, miRNA microarray analysis and further real-time PCR experiments with STAT3 siRNA treatment show that STAT3 activation is related to the up-regulation of miR-17-92 clusters in retinoblastoma cells via positive feedback loop between them. In conclusion, we suggest that STAT3 inhibition could be a potential therapeutic approach in retinoblastoma through the suppression of tumor proliferation. PMID:25359779

  2. STAT3 inhibition suppresses proliferation of retinoblastoma through down-regulation of positive feedback loop of STAT3/miR-17-92 clusters.

    PubMed

    Jo, Dong Hyun; Kim, Jin Hyoung; Cho, Chang Sik; Cho, Young-Lai; Jun, Hyoung Oh; Yu, Young Suk; Min, Jeong-Ki; Kim, Jeong Hun

    2014-11-30

    Retinoblastoma, the most common intraocular malignant tumor in children, is characterized by the loss of both functional alleles of RB1 gene, which however alone cannot maintain malignant characteristics of retinoblastoma cells. Nevertheless, the investigation of other molecular aberrations such as matrix metalloproteinases (MMPs) and miRNAs is still lacking. In this study, we demonstrate that STAT3 is activated in retinoblastoma cells, Ki67-positive areas of in vivo orthotopic tumors in BALB/c nude mice, and human retinoblastoma tissues of the advanced stage. Furthermore, target genes of STAT3 including BCL2, BCL2L1, BIRC5, and MMP9 are up-regulated in retinoblastoma cells compared to other retinal constituent cells. Interestingly, STAT3 inhibition by targeted siRNA suppresses the proliferation of retinoblastoma cells and the formation of in vivo orthotopic tumors. In line with these results, STAT3 siRNA effectively induces down-regulation of target genes of STAT3. In addition, miRNA microarray analysis and further real-time PCR experiments with STAT3 siRNA treatment show that STAT3 activation is related to the up-regulation of miR-17-92 clusters in retinoblastoma cells via positive feedback loop between them. In conclusion, we suggest that STAT3 inhibition could be a potential therapeutic approach in retinoblastoma through the suppression of tumor proliferation. PMID:25359779

  3. Human Cytomegalovirus Immediate-Early 1 Protein Rewires Upstream STAT3 to Downstream STAT1 Signaling Switching an IL6-Type to an IFNγ-Like Response

    PubMed Central

    Lukas, Simone; Zenger, Marion; Reitberger, Tobias; Danzer, Daniela; Übner, Theresa; Munday, Diane C.; Paulus, Christina

    2016-01-01

    The human cytomegalovirus (hCMV) major immediate-early 1 protein (IE1) is best known for activating transcription to facilitate viral replication. Here we present transcriptome data indicating that IE1 is as significant a repressor as it is an activator of host gene expression. Human cells induced to express IE1 exhibit global repression of IL6- and oncostatin M-responsive STAT3 target genes. This repression is followed by STAT1 phosphorylation and activation of STAT1 target genes normally induced by IFNγ. The observed repression and subsequent activation are both mediated through the same region (amino acids 410 to 445) in the C-terminal domain of IE1, and this region serves as a binding site for STAT3. Depletion of STAT3 phenocopies the STAT1-dependent IFNγ-like response to IE1. In contrast, depletion of the IL6 receptor (IL6ST) or the STAT kinase JAK1 prevents this response. Accordingly, treatment with IL6 leads to prolonged STAT1 instead of STAT3 activation in wild-type IE1 expressing cells, but not in cells expressing a mutant protein (IE1dl410-420) deficient for STAT3 binding. A very similar STAT1-directed response to IL6 is also present in cells infected with a wild-type or revertant hCMV, but not an IE1dl410-420 mutant virus, and this response results in restricted viral replication. We conclude that IE1 is sufficient and necessary to rewire upstream IL6-type to downstream IFNγ-like signaling, two pathways linked to opposing actions, resulting in repressed STAT3- and activated STAT1-responsive genes. These findings relate transcriptional repressor and activator functions of IE1 and suggest unexpected outcomes relevant to viral pathogenesis in response to cytokines or growth factors that signal through the IL6ST-JAK1-STAT3 axis in hCMV-infected cells. Our results also reveal that IE1, a protein considered to be a key activator of the hCMV productive cycle, has an unanticipated role in tempering viral replication. PMID:27387064

  4. Human Cytomegalovirus Immediate-Early 1 Protein Rewires Upstream STAT3 to Downstream STAT1 Signaling Switching an IL6-Type to an IFNγ-Like Response.

    PubMed

    Harwardt, Thomas; Lukas, Simone; Zenger, Marion; Reitberger, Tobias; Danzer, Daniela; Übner, Theresa; Munday, Diane C; Nevels, Michael; Paulus, Christina

    2016-07-01

    The human cytomegalovirus (hCMV) major immediate-early 1 protein (IE1) is best known for activating transcription to facilitate viral replication. Here we present transcriptome data indicating that IE1 is as significant a repressor as it is an activator of host gene expression. Human cells induced to express IE1 exhibit global repression of IL6- and oncostatin M-responsive STAT3 target genes. This repression is followed by STAT1 phosphorylation and activation of STAT1 target genes normally induced by IFNγ. The observed repression and subsequent activation are both mediated through the same region (amino acids 410 to 445) in the C-terminal domain of IE1, and this region serves as a binding site for STAT3. Depletion of STAT3 phenocopies the STAT1-dependent IFNγ-like response to IE1. In contrast, depletion of the IL6 receptor (IL6ST) or the STAT kinase JAK1 prevents this response. Accordingly, treatment with IL6 leads to prolonged STAT1 instead of STAT3 activation in wild-type IE1 expressing cells, but not in cells expressing a mutant protein (IE1dl410-420) deficient for STAT3 binding. A very similar STAT1-directed response to IL6 is also present in cells infected with a wild-type or revertant hCMV, but not an IE1dl410-420 mutant virus, and this response results in restricted viral replication. We conclude that IE1 is sufficient and necessary to rewire upstream IL6-type to downstream IFNγ-like signaling, two pathways linked to opposing actions, resulting in repressed STAT3- and activated STAT1-responsive genes. These findings relate transcriptional repressor and activator functions of IE1 and suggest unexpected outcomes relevant to viral pathogenesis in response to cytokines or growth factors that signal through the IL6ST-JAK1-STAT3 axis in hCMV-infected cells. Our results also reveal that IE1, a protein considered to be a key activator of the hCMV productive cycle, has an unanticipated role in tempering viral replication. PMID:27387064

  5. STAT3 selectively interacts with Smad3 to antagonize TGF-β.

    PubMed

    Wang, G; Yu, Y; Sun, C; Liu, T; Liang, T; Zhan, L; Lin, X; Feng, X-H

    2016-08-18

    Smad and STAT proteins are critical signal transducers and transcription factors in controlling cell growth and tumorigenesis. Here we report that the STAT3 signaling pathway attenuates transforming growth factor-β (TGF-β)-induced responses through a direct Smad3-STAT3 interplay. Activated STAT3 blunts TGF-β-mediated signaling. Depletion of STAT3 promotes TGF-β-mediated transcriptional and physiological responses, including cell cycle arrest, apoptosis and epithelial-to-mesenchymal transition. STAT3 directly interacts with Smad3 in vivo and in vitro, resulting in attenuation of the Smad3-Smad4 complex formation and suppression of DNA-binding ability of Smad3. The N-terminal region of DNA-binding domain of STAT3 is responsible for the STAT3-Smad3 interaction and also indispensable for STAT3-mediated inhibition of TGF-β signaling. Thus, our finding illustrates a direct crosstalk between the STAT3 and Smad3 signaling pathways that may contribute to tumor development and inflammation. PMID:26616859

  6. Mechanisms of STAT3 activation in the liver of FXR knockout mice.

    PubMed

    Li, Guodong; Zhu, Yan; Tawfik, Ossama; Kong, Bo; Williams, Jessica A; Zhan, Le; Kassel, Karen M; Luyendyk, James P; Wang, Li; Guo, Grace L

    2013-12-01

    Farnesoid X receptor (FXR, Nr1h4) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily. FXR is essential in maintaining bile acid (BA) homeostasis, and FXR(-/-) mice develop cholestasis, inflammation, and spontaneous liver tumors. The signal transducer and activator of transcription 3 (STAT3) is well known to regulate liver growth, and STAT3 is feedback inhibited by its target gene, the suppressor of cytokine signaling 3 (SOCS3). Strong activation of STAT3 was detected in FXR(-/-) mouse livers. However, the mechanism of STAT3 activation with FXR deficiency remains elusive. Wild-type (WT) and FXR(-/-) mice were used to detect STAT3 pathway activation in the liver. In vivo BA feeding or deprivation was used to determine the role of BAs in STAT3 activation, and in vitro molecular approaches were used to determine the direct transcriptional regulation of SOCS3 by FXR. STAT3 was activated in FXR(-/-) but not WT mice. BA feeding increased, but deprivation by cholestyramine reduced, serum inflammatory markers and STAT3 activation. Furthermore, the Socs3 gene was determined as a direct FXR target gene. The elevated BAs and inflammation, along with reduced SOCS3, collectively contribute to the activation of the STAT3 signaling pathway in the liver of FXR(-/-) mice. This study suggests that the constitutive activation of STAT3 may be a mechanism of liver carcinogenesis in FXR(-/-) mice. PMID:24091600

  7. Mechanisms of STAT3 activation in the liver of FXR knockout mice

    PubMed Central

    Li, Guodong; Zhu, Yan; Tawfik, Ossama; Kong, Bo; Williams, Jessica A.; Zhan, Le; Kassel, Karen M.; Luyendyk, James P.; Wang, Li

    2013-01-01

    Farnesoid X receptor (FXR, Nr1h4) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily. FXR is essential in maintaining bile acid (BA) homeostasis, and FXR−/− mice develop cholestasis, inflammation, and spontaneous liver tumors. The signal transducer and activator of transcription 3 (STAT3) is well known to regulate liver growth, and STAT3 is feedback inhibited by its target gene, the suppressor of cytokine signaling 3 (SOCS3). Strong activation of STAT3 was detected in FXR−/− mouse livers. However, the mechanism of STAT3 activation with FXR deficiency remains elusive. Wild-type (WT) and FXR−/− mice were used to detect STAT3 pathway activation in the liver. In vivo BA feeding or deprivation was used to determine the role of BAs in STAT3 activation, and in vitro molecular approaches were used to determine the direct transcriptional regulation of SOCS3 by FXR. STAT3 was activated in FXR−/− but not WT mice. BA feeding increased, but deprivation by cholestyramine reduced, serum inflammatory markers and STAT3 activation. Furthermore, the Socs3 gene was determined as a direct FXR target gene. The elevated BAs and inflammation, along with reduced SOCS3, collectively contribute to the activation of the STAT3 signaling pathway in the liver of FXR−/− mice. This study suggests that the constitutive activation of STAT3 may be a mechanism of liver carcinogenesis in FXR−/− mice. PMID:24091600

  8. Glia maturation factor regulation of STAT expression: a novel mechanism in experimental autoimmune encephalomyelitis.

    PubMed

    Zaheer, Smita; Wu, Yanghong; Bassett, Jon; Yang, Baoli; Zaheer, Asgar

    2007-12-01

    Inflammatory cytokines are implemented in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. We previously demonstrated that glia maturation factor (GMF), a brain protein, isolated, sequenced and cloned in our laboratory, induce expression of proinflammatory cytokine/chemokine in the central nervous system (CNS). We found GMF-deficient (knockout) mice relatively resistant to EAE development after immunization with encephalitogenic MOG peptide 35-55. Consistent with these findings, the expression of proinflammatory cytokines in CNS of mice with EAE differed profoundly between wild type and GMF-knockout mice. In the present study we examined the expressions of six murine signal transducers and activators of transcription (STATs) genes, which are known to regulate the cytokine-dependent signal transduction pathways in autoimmune inflammation. The expressions of STATs genes were evaluated in the brains and spinal cords of wild type and GMF-knockout mice at the peak of EAE by quantitative real-time RT-PCR. Compared to GMF-knockout mice, the expressions of STAT1, STAT2, STAT3, STAT4, STAT5, and STAT6 genes were significantly (P < 0.001) upregulated in the wild type mice exhibiting EAE symptoms. The results are consistent with the diminished development of EAE in the GMF-knockout mice. A significant suppression of STATs expression in GMF-knockout mice suggests GMF as an upstream effector of JAK/STAT signaling. PMID:17551829

  9. Modulation of STAT3 Folding and Function by TRiC/CCT Chaperonin

    PubMed Central

    Kasembeli, Moses; Lau, Wilson Chun Yu; Roh, Soung-Hun; Eckols, T. Kris; Frydman, Judith; Chiu, Wah; Tweardy, David J.

    2014-01-01

    Signal transducer and activator of transcription 3 (Stat3) transduces signals of many peptide hormones from the cell surface to the nucleus and functions as an oncoprotein in many types of cancers, yet little is known about how it achieves its native folded state within the cell. Here we show that Stat3 is a novel substrate of the ring-shaped hetero-oligomeric eukaryotic chaperonin, TRiC/CCT, which contributes to its biosynthesis and activity in vitro and in vivo. TRiC binding to Stat3 was mediated, at least in part, by TRiC subunit CCT3. Stat3 binding to TRiC mapped predominantly to the β-strand rich, DNA-binding domain of Stat3. Notably, enhancing Stat3 binding to TRiC by engineering an additional TRiC-binding domain from the von Hippel-Lindau protein (vTBD), at the N-terminus of Stat3, further increased its affinity for TRiC as well as its function, as determined by Stat3's ability to bind to its phosphotyrosyl-peptide ligand, an interaction critical for Stat3 activation. Thus, Stat3 levels and function are regulated by TRiC and can be modulated by manipulating its interaction with TRiC. PMID:24756126

  10. The measles virus phosphoprotein interacts with the linker domain of STAT1

    SciTech Connect

    Devaux, Patricia Priniski, Lauren; Cattaneo, Roberto

    2013-09-15

    The measles virus (MV) phosphoprotein (P) and V proteins block the interferon (IFN) response by impeding phosphorylation of the signal transducer and activator of transcription 1 (STAT1) by the Janus kinase 1 (JAK1). We characterized how STAT1 mutants interact with P and JAK1 phosphorylation. Certain mutants of the linker, the Src-homology 2 domain (SH2), or the transactivation domain had reduced or abolished phosphorylation through JAK1 after IFN treatment. Other mutants, mainly localized in the linker, failed to interact with P as documented by the lack of interference with nuclear translocation. Thus the functional footprint of P on STAT1 localizes mainly to the linker domain; there is also some overlap with the STAT1 phosphorylation functional footprint on the SH2 domain. Based on these observations, we discuss how the MV-P might operate to inhibit the JAK/STAT pathway. - Highlights: • Residue in the linker and SH2 domains of STAT1 are important for MV-P interaction. • Residue in the linker and SH2 domains of STAT1 are important for STAT1 phosphorylation. • Residues interferring with both functions have similar location on STAT1. • The viral P and V proteins may operate in concert to inhibit the JAK/STAT pathway.

  11. The STAT pathway mediates late phase immunity against Plasmodium in the mosquito Anopheles gambiae

    PubMed Central

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E.; Barillas-Mury, Carolina

    2009-01-01

    The STAT family of transcription factors activate expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late phase anti-plasmodial response that reduces oocyst survival in An. gambiae. PMID:19454353

  12. The STAT pathway mediates late-phase immunity against Plasmodium in the mosquito Anopheles gambiae.

    PubMed

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E; Barillas-Mury, Carolina

    2009-05-01

    The STAT family of transcription factors activates expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late-phase antiplasmodial response that reduces oocyst survival in A. gambiae. PMID:19454353

  13. Myeloid STAT3 promotes formation of colitis-associated colorectal cancer in mice

    PubMed Central

    Pathria, Paulina; Gotthardt, Dagmar; Prchal-Murphy, Michaela; Putz, Eva-Maria; Holcmann, Martin; Schlederer, Michaela; Grabner, Beatrice; Crncec, Ilija; Svinka, Jasmin; Musteanu, Monica; Hoffmann, Thomas; Filipits, Martin; Berger, Walter; Poli, Valeria; Kenner, Lukas; Bilban, Martin; Casanova, Emilio; Müller, Mathias; Strobl, Birgit; Bayer, Editha; Mohr, Thomas; Sexl, Veronika; Eferl, Robert

    2015-01-01

    Myeloid cells lacking STAT3 promote antitumor responses of NK and T cells but it is unknown if this crosstalk affects development of autochthonous tumors. We deleted STAT3 in murine myeloid cells (STAT3Δm) and examined the effect on the development of autochthonous colorectal cancers (CRCs). Formation of Azoxymethane/Dextransulfate (AOM/DSS)-induced CRCs was strongly suppressed in STAT3Δm mice. Gene expression profiling showed strong activation of T cells in the stroma of STAT3Δm CRCs. Moreover, STAT3Δm host mice were better able to control the growth of transplanted MC38 colorectal tumor cells which are known to be killed in a T cell-dependent manner. These data suggest that myeloid cells lacking STAT3 control formation of CRCs mainly via cross activation of T cells. Interestingly, the few CRCs that formed in STAT3Δm mice displayed enhanced stromalization but appeared normal in size indicating that they have acquired ways to escape enhanced tumor surveillance. We found that CRCs in STAT3Δm mice consistently activate STAT3 signaling which is implicated in immune evasion and might be a target to prevent tumor relapse. PMID:26137415

  14. Withaferin A Inhibits STAT3 and Induces Tumor Cell Death in Neuroblastoma and Multiple Myeloma

    PubMed Central

    Yco, Lisette P; Mocz, Gabor; Opoku-Ansah, John; Bachmann, André S

    2014-01-01

    Signal transducer and activator of transcription 3 (STAT3) is an oncogenic transcription factor that has been implicated in many human cancers and has emerged as an ideal target for cancer therapy. Withaferin A (WFA) is a natural product with promising antiproliferative properties through its association with a number of molecular targets including STAT3. However, the effect of WFA in pediatric neuroblastoma (NB) and its interaction with STAT3 have not been reported. In this study, we found that WFA effectively induces dose-dependent cell death in high-risk and drug-resistant NB as well as multiple myeloma (MM) tumor cells, prevented interleukin-6 (IL-6)–mediated and persistently activated STAT3 phosphorylation at Y705, and blocked the transcriptional activity of STAT3. We further provide computational models that show that WFA binds STAT3 near the Y705 phospho-tyrosine residue of the STAT3 Src homology 2 (SH2) domain, suggesting that WFA prevents STAT3 dimer formation similar to BP-1-102, a well-established STAT3 inhibitor. Our findings propose that the antitumor activity of WFA is mediated at least in part through inhibition of STAT3 and provide a rationale for further drug development and clinical use in NB and MM. PMID:25452693

  15. ALA-PDT inhibits proliferation and promotes apoptosis of SCC cells through STAT3 signal pathway.

    PubMed

    Qiao, Li; Mei, Zhusong; Yang, Zhiyong; Li, Xinji; Cai, Hong; Liu, Wei

    2016-06-01

    Previous studies suggest that apoptosis of carcinoma cells led by photodynamics is mainly intrinsic apoptosis, but whether the extrinsic pathway is involved in the treatment of carcinoma by photodynamic therapy is not confirmed. This research investigated the effect of ALA-PDT on the proliferation and apoptosis of SCC cell A431 and COLO-16, and discussed the role played by JAK/STAT3 signal pathway in this process. Our data showed that the expression levels STAT3 and p-STAT3 protein in the cancer tissue are higher than the corresponding adjacent tissue to carcinoma. The expression level of p-STAT3 in cancerous tissue has a correlation with the tumor size and tissue histopathological differentiation. ALA-PDT could inhibit proliferation of A431 and COLO-16 cells, STAT3 knock down could enhance ALA-PDT's inhibition of cell proliferation, and promote apoptosis induced by ALA-PDT. On the other hand, overexpression of STAT3 has the opposite effect. In addition, ALA-PDT can weaken the protein expression of STAT3 and its target gene Bcl-2 mRNA, and ALA-PDT can strengthen the protein expression of STAT3's target gene Bax mRNA. Overexpression of STAT3 can offset the effect on Bcl-2 and Bax by ALA-PDT; on the other hand, STAT3 knocking down can strengthen ALA-PDT's effect on Bcl-2 and Bax. PMID:26805005

  16. Activation of different Stat5 isoforms contributes to cell-type-restricted signaling in response to interferons.

    PubMed Central

    Meinke, A; Barahmand-Pour, F; Wöhrl, S; Stoiber, D; Decker, T

    1996-01-01

    Tyrosine phosphorylation and activation of the transcription factor Stat5 occur in response to stimuli like granulocyte-macrophage colony-stimulating factor, interleukin-3, or erythropoietin that stimulate both proliferation and differentiation of hematopoietic cells. It is unclear whether Stat5 is part of a proliferative response or part of the events leading to cellular differentiation. Here we report that agents promoting differentiation but not proliferation of hematopoietic cells, like phorbol ester or both types of interferons (IFNs), activate Stat5 in promonocytic U937 cells. Both IFN types caused tyrosine phosphorylation and DNA binding of predominantly one Stat5 isoform (Stat5a) despite expression of both Stat5a and Stat5b proteins. Monocytic differentiation of U937 cells led to a strong decrease in IFN-gamma-mediated activation of Stat5 but not of Stat1. Transactivation of Stat5-target genes occurred in response to IFN-gamma, which activates both Stat5 and Stat1, but not in response to granulocyte-macrophage colony-stimulating factor, which activates only Stat5. Tyrosine phosphorylation of Stat5 is not generally part of the IFN response. IFN-gamma did not cause Stat5 activation in HeLa cells, despite the expression of both Stat5 isoforms at similar levels. By contrast, IFN-alpha caused tyrosine phosphorylation and DNA binding of exclusively the b isoform of Stat5, and activated Stat5b formed a DNA binding activity previously found in HeLa cells and designated IFN-alpha activation factor 2. Taken together, our results demonstrate that ligand binding of IFN receptors leads to an isoform-specific activation of Stat5 in a restricted number of cell lineages. Moreover, they suggest that Stat5 might be part of the differentiation response of myeloid cells. PMID:8943349

  17. Fetal anemia and apoptosis of red cell progenitors in Stat5a-/-5b-/- mice: a direct role for Stat5 in Bcl-X(L) induction.

    PubMed

    Socolovsky, M; Fallon, A E; Wang, S; Brugnara, C; Lodish, H F

    1999-07-23

    The erythropoietin receptor (EpoR) is essential for production of red blood cells; a principal function of EpoR is to rescue committed erythroid progenitors from apoptosis. Stat5 is rapidly activated following EpoR stimulation, but its function in erythropoiesis has been unclear since adult St