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Sample records for hiv-1 transmitting couples

  1. Transmitted drug resistance in nonsubtype B HIV-1 infection

    PubMed Central

    Chan, Philip A; Kantor, Rami

    2009-01-01

    HIV-1 nonsubtype B variants account for the majority of HIV infections worldwide. Drug resistance in individuals who have never undergone antiretroviral therapy can lead to early failure and limited treatment options and, therefore, is an important concern. Evaluation of reported transmitted drug resistance (TDR) is challenging owing to varying definitions and study designs, and is further complicated by HIV-1 subtype diversity. In this article, we discuss the importance of various mutation lists for TDR definition, summarize TDR in nonsubtype B HIV-1 and highlight TDR reporting and interpreting challenges in the context of HIV-1 diversity. When examined carefully, TDR in HIV-1 non-B protease and reverse transcriptase is still relatively low in most regions. Whether it will increase with time and therapy access, as observed in subtype-B-predominant regions, remains to be determined. PMID:20161523

  2. Persistence of HIV-1 transmitted drug resistance mutations.

    PubMed

    Castro, Hannah; Pillay, Deenan; Cane, Patricia; Asboe, David; Cambiano, Valentina; Phillips, Andrew; Dunn, David T

    2013-11-01

    There are few data on the persistence of individual human immunodeficiency virus type 1 (HIV-1) transmitted drug resistance (TDR) mutations in the absence of selective drug pressure. We studied 313 patients in whom TDR mutations were detected at their first resistance test and who had a subsequent test performed while ART-naive. The rate at which mutations became undetectable was estimated using exponential regression accounting for interval censoring. Most thymidine analogue mutations (TAMs) and T215 revertants (but not T215F/Y) were found to be highly stable, with NNRTI and PI mutations being relatively less persistent. Our estimates are important for informing HIV transmission models.

  3. Regional Differences in Prevalence of HIV-1 Discordance in Africa and Enrollment of HIV-1 Discordant Couples into an HIV-1 Prevention Trial

    PubMed Central

    Lingappa, Jairam R.; Lambdin, Barrot; Bukusi, Elizabeth Ann; Ngure, Kenneth; Kavuma, Linda; Inambao, Mubiana; Kanweka, William; Allen, Susan; Kiarie, James N.; Makhema, Joseph; Were, Edwin; Manongi, Rachel; Coetzee, David; de Bruyn, Guy; Delany-Moretlwe, Sinead; Magaret, Amalia; Mugo, Nelly; Mujugira, Andrew; Ndase, Patrick; Celum, Connie

    2008-01-01

    Background Most HIV-1 transmission in Africa occurs among HIV-1-discordant couples (one partner HIV-1 infected and one uninfected) who are unaware of their discordant HIV-1 serostatus. Given the high HIV-1 incidence among HIV-1 discordant couples and to assess efficacy of interventions for reducing HIV-1 transmission, HIV-1 discordant couples represent a critical target population for HIV-1 prevention interventions and prevention trials. Substantial regional differences exist in HIV-1 prevalence in Africa, but regional differences in HIV-1 discordance among African couples, has not previously been reported. Methodology/Principal Findings The Partners in Prevention HSV-2/HIV-1 Transmission Trial (“Partners HSV-2 Study”), the first large HIV-1 prevention trial in Africa involving HIV-1 discordant couples, completed enrollment in May 2007. Partners HSV-2 Study recruitment data from 12 sites from East and Southern Africa were used to assess HIV-1 discordance among couples accessing couples HIV-1 counseling and testing, and to correlate with enrollment of HIV-1 discordant couples. HIV-1 discordance at Partners HSV-2 Study sites ranged from 8–31% of couples tested from the community. Across all study sites and, among all couples with one HIV-1 infected partner, almost half (49%) of couples were HIV-1 discordant. Site-specific monthly enrollment of HIV-1 discordant couples into the clinical trial was not directly associated with prevalence of HIV-1 discordance, but was modestly correlated with national HIV-1 counseling and testing rates and access to palliative care/basic health care (r = 0.74, p = 0.09). Conclusions/Significance HIV-1 discordant couples are a critical target for HIV-1 prevention in Africa. In addition to community prevalence of HIV-1 discordance, national infrastructure for HIV-1 testing and healthcare delivery and effective community outreach strategies impact recruitment of HIV-1 discordant couples into HIV-1 prevention trials. PMID

  4. Differential Persistence of Transmitted HIV-1 Drug Resistance Mutation Classes

    PubMed Central

    Jain, Vivek; Sucupira, Maria C.; Bacchetti, Peter; Hartogensis, Wendy; Diaz, Ricardo S.; Kallas, Esper G.; Janini, Luiz M.; Liegler, Teri; Pilcher, Christopher D.; Grant, Robert M.; Cortes, Rodrigo; Deeks, Steven G.

    2011-01-01

    Background. Transmitted human immunodeficiency virus type 1 (HIV-1) drug resistance (TDR) mutations can become replaced over time by emerging wild-type viral variants with improved fitness. The impact of class-specific mutations on this rate of mutation replacement is uncertain. Methods. We studied participants with acute and/or early HIV infection and TDR in 2 cohorts (San Francisco, California, and São Paulo, Brazil). We followed baseline mutations longitudinally and compared replacement rates between mutation classes with use of a parametric proportional hazards model. Results. Among 75 individuals with 195 TDR mutations, M184V/I became undetectable markedly faster than did nonnucleoside reverse-transcriptase inhibitor (NNRTI) mutations (hazard ratio, 77.5; 95% confidence interval [CI], 14.7–408.2; P < .0001), while protease inhibitor and NNRTI replacement rates were similar. Higher plasma HIV-1 RNA level predicted faster mutation replacement, but this was not statistically significant (hazard ratio, 1.71 log10 copies/mL; 95% CI, .90–3.25 log10 copies/mL; P = .11). We found substantial person-to-person variability in mutation replacement rates not accounted for by viral load or mutation class (P < .0001). Conclusions. The rapid replacement of M184V/I mutations is consistent with known fitness costs. The long-term persistence of NNRTI and protease inhibitor mutations suggests a risk for person-to-person propagation. Host and/or viral factors not accounted for by viral load or mutation class are likely influencing mutation replacement and warrant further study. PMID:21451005

  5. Characteristics of HIV-1 Discordant Couples Enrolled in a Trial of HSV-2 Suppression to Reduce HIV-1 Transmission: The Partners Study

    PubMed Central

    Lingappa, Jairam R.; Kahle, Erin; Mugo, Nelly; Mujugira, Andrew; Magaret, Amalia; Baeten, Jared; Bukusi, Elizabeth A.; Cohen, Craig R.; Katabira, Elly; Ronald, Allan; Kiarie, James; Farquhar, Carey; Stewart, Grace John; Makhema, Joseph; Essex, M.; Were, Edwin; Fife, Kenneth; deBruyn, Guy; Gray, Glenda; McIntyre, James; Manongi, Rachel; Kapiga, Saidi; Coetzee, David; Allen, Susan; Inambao, Mubiana; Kayitenkore, Kayitesi; Karita, Etienne; Kanweka, William; Delany, Sinead; Rees, Helen; Vwalika, Bellington; Coombs, Robert W.; Morrow, Rhoda; Whittington, William; Corey, Lawrence; Wald, Anna; Celum, Connie

    2009-01-01

    Background The Partners HSV-2/HIV-1 Transmission Study (Partners Study) is a phase III, placebo-controlled trial of daily acyclovir for genital herpes (HSV-2) suppression among HIV-1/HSV-2 co-infected persons to reduce HIV-1 transmission to their HIV-1 susceptible partners, which requires recruitment of HIV-1 serodiscordant heterosexual couples. We describe the baseline characteristics of this cohort. Methods HIV-1 serodiscordant heterosexual couples, in which the HIV-1 infected partner was HSV-2 seropositive, had a CD4 count ≥250 cells/mcL and was not on antiretroviral therapy, were enrolled at 14 sites in East and Southern Africa. Demographic, behavioral, clinical and laboratory characteristics were assessed. Results Of the 3408 HIV-1 serodiscordant couples enrolled, 67% of the HIV-1 infected partners were women. Couples had cohabitated for a median of 5 years (range 2–9) with 28% reporting unprotected sex in the month prior to enrollment. Among HIV-1 susceptible participants, 86% of women and 59% of men were HSV-2 seropositive. Other laboratory-diagnosed sexually transmitted infections were uncommon (<5%), except for Trichomonas vaginalis in 14% of HIV-1 infected women. Median baseline CD4 count for HIV-1 infected participants was 462cells/mcL and median HIV-1 plasma RNA was 4.2 log10 copies/mL. After adjusting for age and African region, correlates of HIV-1 RNA level included male gender (+0.24 log10 copies/mL; p<0.001) and CD4 count (−0.25 and −0.55 log10 copies/mL for CD4 350–499 and >500 relative to <350, respectively, p<0.001). Conclusions The Partners Study successfully enrolled a cohort of 3408 heterosexual HIV-1 serodiscordant couples in Africa at high risk for HIV-1 transmission. Follow-up of this cohort will evaluate the efficacy of acyclovir for HSV-2 suppression in preventing HIV-1 transmission and provide insights into biological and behavioral factors determining heterosexual HIV-1 transmission. Trial Registration ClinicalTrials.gov NCT

  6. The Role of Sexually Transmitted Infections in HIV-1 Progression: A Comprehensive Review of the Literature

    PubMed Central

    Chun, Helen M.; Carpenter, Robert J.; Macalino, Grace E.; Crum-Cianflone, Nancy F.

    2013-01-01

    Due to shared routes of infection, HIV-infected persons are frequently coinfected with other sexually transmitted infections (STIs). Studies have demonstrated the bidirectional relationships between HIV and several STIs, including herpes simplex virus-2 (HSV-2), hepatitis B and C viruses, human papilloma virus, syphilis, gonorrhea, chlamydia, and trichomonas. HIV-1 may affect the clinical presentation, treatment outcome, and progression of STIs, such as syphilis, HSV-2, and hepatitis B and C viruses. Likewise, the presence of an STI may increase both genital and plasma HIV-1 RNA levels, enhancing the transmissibility of HIV-1, with important public health implications. Regarding the effect of STIs on HIV-1 progression, the most studied interrelationship has been with HIV-1/HSV-2 coinfection, with recent studies showing that antiherpetic medications slow the time to CD4 <200 cells/µL and antiretroviral therapy among coinfected patients. The impact of other chronic STIs (hepatitis B and C) on HIV-1 progression requires further study, but some studies have shown increased mortality rates. Treatable, nonchronic STIs (i.e., syphilis, gonorrhea, chlamydia, and trichomonas) typically have no or transient impacts on plasma HIV RNA levels that resolve with antimicrobial therapy; no long-term effects on outcomes have been shown. Future studies are advocated to continue investigating the complex interplay between HIV-1 and other STIs. PMID:26316953

  7. Spermatozoa capture HIV-1 through heparan sulfate and efficiently transmit the virus to dendritic cells

    PubMed Central

    Ceballos, Ana; Remes Lenicov, Federico; Sabatté, Juan; Rodríguez Rodrígues, Christian; Cabrini, Mercedes; Jancic, Carolina; Raiden, Silvina; Donaldson, Mónica; Agustín Pasqualini, Rodolfo; Marin-Briggiler, Clara; Vazquez-Levin, Mónica; Capani, Francisco; Amigorena, Sebastián

    2009-01-01

    Semen is the main vector for HIV-1 dissemination worldwide. It contains three major sources of infectious virus: free virions, infected leukocytes, and spermatozoa-associated virions. We focused on the interaction of HIV-1 with human spermatozoa and dendritic cells (DCs). We report that heparan sulfate is expressed in spermatozoa and plays an important role in the capture of HIV-1. Spermatozoa-attached virus is efficiently transmitted to DCs, macrophages, and T cells. Interaction of spermatozoa with DCs not only leads to the transmission of HIV-1 and the internalization of the spermatozoa but also results in the phenotypic maturation of DCs and the production of IL-10 but not IL-12p70. At low values of extracellular pH (∼6.5 pH units), similar to those found in the vaginal mucosa after sexual intercourse, the binding of HIV-1 to the spermatozoa and the consequent transmission of HIV-1 to DCs were strongly enhanced. Our observations support the notion that far from being a passive carrier, spermatozoa acting in concert with DCs might affect the early course of sexual transmission of HIV-1 infection. PMID:19858326

  8. An empiric risk scoring tool for identifying high-risk heterosexual HIV-1 serodiscordant couples for targeted HIV-1 prevention

    PubMed Central

    KAHLE, Erin M.; HUGHES, James P.; LINGAPPA, Jairam R.; JOHN-STEWART, Grace; CELUM, Connie; NAKKU-JOLOBA, Edith; NJUGUNA, Stella; MUGO, Nelly; BUKUSI, Elizabeth; MANONGI, Rachel; BAETEN, Jared M.

    2012-01-01

    Background and objectives Heterosexual HIV-1 serodiscordant couples are increasingly recognized as an important source of new HIV-1 infections in sub-Saharan Africa. A simple risk assessment tool could be useful for identifying couples at highest risk for HIV-1 transmission. Methods Using data from three prospective studies of HIV-1 serodiscordant couples from seven African countries and standard methods for development of clinical prediction rules, we derived and validated a risk scoring tool developed from multivariate modeling and composed of key predictors for HIV-1 risk that could be measured in standard research and clinical settings. Results The final risk score included age of the HIV-1 uninfected partner, married and/or cohabiting partnership, number of children, unprotected sex, uncircumcised male HIV-1 uninfected partner, and plasma HIV-1 RNA in the HIV-1 infected partner. The maximum risk score was 12, scores ≥5 were associated with an annual HIV-1 incidence of >3%, and couples with a score ≥6 accounted for only 28% of the population but 67% of HIV-1 transmissions. The area under the curve for predictive ability of the score was 0.74 (95% CI 0.70–0.78). Internal and external validation showed similar predictive ability of the risk score, even when plasma viral load was excluded from the risk score. Conclusions A discrete combination of clinical and behavioral characteristics defines highest-risk HIV-1 serodiscordant couples. Discriminating highest-risk couples for HIV-1 prevention programs and clinical trials using a validated risk score could improve research efficiency and maximize the impact of prevention strategies for reducing HIV-1 transmission. PMID:23187945

  9. HIV-1 Transmitted Drug Resistance Mutations in Newly Diagnosed Antiretroviral-Naive Patients in Turkey.

    PubMed

    Sayan, Murat; Sargin, Fatma; Inan, Dilara; Sevgi, Dilek Y; Celikbas, Aysel K; Yasar, Kadriye; Kaptan, Figen; Kutlu, Selda; Fisgin, Nuriye T; Inci, Ayse; Ceran, Nurgul; Karaoglan, Ilkay; Cagatay, Atahan; Celen, Mustafa K; Koruk, Suda T; Ceylan, Bahadir; Yildirmak, Taner; Akalın, Halis; Korten, Volkan; Willke, Ayse

    2016-01-01

    HIV-1 replication is rapid and highly error-prone. Transmission of a drug-resistant HIV-1 strain is possible and occurs within the HIV-1-infected population. In this study, we aimed to determine the prevalence of transmitted drug resistance mutations (TDRMs) in 1,306 newly diagnosed untreated HIV-1-infected patients from 21 cities across six regions of Turkey between 2010 and 2015. TDRMs were identified according to the criteria provided by the World Health Organization's 2009 list of surveillance drug resistance mutations. The HIV-1 TDRM prevalence was 10.1% (133/1,306) in Turkey. Primary drug resistance mutations (K65R, M184V) and thymidine analogue-associated mutations (TAMs) were evaluated together as nucleos(t)ide reverse transcriptase inhibitor (NRTI) mutations. NRTI TDRMs were found in 8.1% (107/1,306) of patients. However, TAMs were divided into three categories and M41L, L210W, and T215Y mutations were found for TAM1 in 97 (7.4%) patients, D67N, K70R, K219E/Q/N/R, T215F, and T215C/D/S mutations were detected for TAM2 in 52 (3.9%) patients, and M41L + K219N and M41L + T215C/D/S mutations were detected for the TAM1 + TAM2 profile in 22 (1.7%) patients, respectively. Nonnucleoside reverse transcriptase inhibitor-associated TDRMs were detected in 3.3% (44/1,306) of patients (L100I, K101E/P, K103N/S, V179F, Y188H/L/M, Y181I/C, and G190A/E/S) and TDRMs to protease inhibitors were detected in 2.3% (30/1,306) of patients (M46L, I50V, I54V, Q58E, L76V, V82A/C/L/T, N83D, I84V, and L90M). In conclusion, long-term and large-scale monitoring of regional levels of HIV-1 TDRMs informs treatment guidelines and provides feedback on the success of HIV-1 prevention and treatment efforts. PMID:26414663

  10. Change in the Prevalence of HIV-1 and the Rate of Transmitted Drug-Resistant HIV-1 in Haiphong, Northern Vietnam.

    PubMed

    Pham, Hung Viet; Ishizaki, Azumi; Nguyen, Cuong Hung; Saina, Matilda Chelimo; Hoang, Huyen Thi Thanh; Tran, Vuong Thi; Bi, Xiuqiong; Pham, Thuc Van; Ichimura, Hiroshi

    2015-07-01

    We previously reported a significant decrease in HIV-1 prevalence, with no increase in drug-resistant HIV-1 among injecting drug users (IDU), female sex workers (FSW), and blood donors (BD), in Haiphong, Vietnam, from 2007 to 2009. In 2012, 388 IDU, 51 FSW, and 200 BD were recruited for further analysis. None had a history of antiretroviral treatment. From 2007 to 2012, HIV-1 prevalence was reduced from 35.9% to 18.6% (p<0.001), 23.1% to 9.8% (p<0.05), and 2.9% to 1% (p=0.29) in IDU, FSW, and BD, respectively. Of 79 anti-HIV-1 antibody-positive samples, 61 were successfully analyzed for the pol-reverse transcriptase (RT) region. All HIV-1 strains were CRF01_AE. Nonnucleoside RT inhibitor-resistant mutations, Y181C/I, were detected in three subjects; one had the nucleoside RT inhibitor-resistant mutations L74V and M184V and one had E138K. The prevalence of transmitted drug-resistant HIV-1 in Haiphong increased slightly from 1.8% in 2007 to 6.6% in 2012 (p=0.06). PMID:25970090

  11. Short communication: Prevalence of HIV-1 transmitted drug resistance in Liberia.

    PubMed

    Loubet, Paul; Charpentier, Charlotte; Visseaux, Benoit; Nuta, Cecilia; Adu, Eric; Chapplain, Jean-Marc; Baysah, Maima; Walters-Doe, Sylvia; Tattevin, Pierre; Peytavin, Gilles; Yazdanpanah, Yazdan; Descamps, Diane

    2014-09-01

    No data on HIV-transmitted drug resistance (TDR) are available in Liberia in which the HIV prevalence in the general population is estimated at 1.5%. The aim of the study was to assess the prevalence of TDR in HIV-1 from recently diagnosed and untreated patients living in Monrovia, Liberia. The study was performed in the John F. Kennedy Medical Center and in the Redemption Hospital, both located in Monrovia. All newly HIV-1 diagnosed patients attending voluntary counseling testing centers and antiretroviral therapy naive were consecutively included. Protease and reverse transcriptase (RT) regions sequencing was performed using the ANRS procedures (www.hivfrenchresistance.org). Drug resistance mutations (DRM) were identified according to the 2009 updated WHO surveillance DRM list. Among the 116 HIV-1-infected patients enrolled in the study, 85 (73%) were women. Protease and RT sequencing was successful in 109 (94%) and 102 (88%) samples, respectively. Seventy-five (66%) patients were infected with CRF02_AG. One DRM was observed in six samples, leading to a TDR prevalence of 5.9% (CI 95%=1.7-10.1). DRM were observed in two patients (2.0%; CI 95%=0.0-4.7), four patients (3.9%; CI 95%=0.1-7.7), and one patient (0.9%; CI 95%=0.0-2.7) for nucleoside RT inhibitors (NRTI), non-NRTI (NNRTI), and protease inhibitors, respectively. Overall, one patient exhibited dual class-resistant viruses, harboring NRTI and NNRTI resistance mutations (1.0%; CI 95%=0.0-2.9). This first survey study in Liberia reported a TDR prevalence of 5.9%, classified as moderate according to the WHO criteria, indicating that further surveillance is warranted to follow the level and evolution of TDR prevalence in recently HIV-1 diagnosed patients. PMID:24946849

  12. Cloning and characterization of functional subtype A HIV-1 envelope variants transmitted through breastfeeding.

    PubMed

    Rainwater, Stephanie M J; Wu, Xueling; Nduati, Ruth; Nedellec, Rebecca; Mosier, Donald; John-Stewart, Grace; Mbori-Ngacha, Dorothy; Overbaugh, Julie

    2007-03-01

    Previous studies of HIV-1 variants transmitted from mother-to-infant have focused primarily on computational analyses of partial envelope gene sequences, rather than analyses of functional envelope variants. There are very few examples of well-characterized functional envelope clones from mother-infant pairs, especially from envelope variants representing the most prevalent subtypes worldwide. To address this, we amplified the envelope variants present in 4 mother-infant transmission pairs, all of whom were infected with subtype A and three of whom presumably transmitted HIV-1 during the breastfeeding period. Functional envelope clones were constructed, either encoding full-length envelope sequences from the mother and baby or by making chimeric envelope clones in a common backbone sequence. The infant envelope sequences were genetically homogeneous compared to the maternal viruses, and pseudoviruses bearing these envelopes all used CCR5 as a coreceptor. The infant viruses were generally resistant to neutralization by maternal antibodies present near the time of transmission. There were no notable differences in sensitivity of the mother and infant envelope variants to neutralization by heterologous plasma or monoclonal antibodies 2G12 and b12, or to inhibition by sCD4, PSC-RANTES or TAK779. This collection of viral envelopes, which can be used for making pseudotyped viruses, may be useful for examining the efficacy of interventions to block mother-infant transmission, including sera from vaccine candidates, purified antibodies under consideration for passive immunization and viral entry inhibitors.

  13. Sentinel Surveillance of HIV-1 Transmitted Drug Resistance, Acute Infection and Recent Infection

    PubMed Central

    Truong, Hong-Ha M.; Kellogg, Timothy A.; McFarland, Willi; Louie, Brian; Klausner, Jeffrey D.; Philip, Susan S.; Grant, Robert M.

    2011-01-01

    Background HIV-1 acute infection, recent infection and transmitted drug resistance screening was integrated into voluntary HIV counseling and testing (VCT) services to enhance the existing surveillance program in San Francisco. This study describes newly-diagnosed HIV cases and characterizes correlates associated with infection. Methodology/Principal Findings A consecutive sample of persons presenting for HIV VCT at the municipal sexually transmitted infections (STI) clinic from 2004 to 2006 (N = 9,868) were evaluated by standard enzyme-linked immunoassays (EIA). HIV antibody-positive specimens were characterized as recent infections using a less-sensitive EIA. HIV-RNA pooled testing was performed on HIV antibody-negative specimens to identify acute infections. HIV antibody-positive and acute infection specimens were evaluated for drug resistance by sequence analysis. Multivariable logistic regression was performed to evaluate associations. The 380 newly-diagnosed HIV cases included 29 acute infections, 128 recent infections, and 47 drug-resistant cases, with no significant increases or decreases in prevalence over the three years studied. HIV-1 transmitted drug resistance prevalence was 11.0% in 2004, 13.4% in 2005 and 14.9% in 2006 (p = 0.36). Resistance to non-nucleoside reverse transcriptase inhibitors (NNRTI) was the most common pattern detected, present in 28 cases of resistance (59.6%). Among MSM, recent infection was associated with amphetamine use (AOR = 2.67; p<0.001), unprotected anal intercourse (AOR = 2.27; p<0.001), sex with a known HIV-infected partner (AOR = 1.64; p = 0.02), and history of gonorrhea (AOR = 1.62; p = 0.03). Conclusions New HIV diagnoses, recent infections, acute infections and transmitted drug resistance prevalence remained stable between 2004 and 2006. Resistance to NNRTI comprised more than half of the drug-resistant cases, a worrisome finding given its role as the backbone of first

  14. Evolving patterns of HIV-1 transmitted drug resistance in Poland in the years 2000-2008.

    PubMed

    Stańczak, Grzegorz P; Stańczak, Janusz J; Marczyńska, Magdalena; Firlag-Burkacka, Ewa; Wiercińska-Drapało, Alicja; Leszczyszyn-Pynka, Magdalena; Jabłonowska, Elzbieta; Małolepsza, Ewa; Dyda, Tomasz; Zabek, Piotr; Horban, Andrzej

    2010-07-01

    The aim of the study was to determine the rate of transmission of drug resistant human immunodeficiency virus-1 (HIV-1) variants among therapy-naïve HIV positive patients in Poland in the year 2008, to compare the data with the results from the years 2000 to 2007 and to monitor patterns of HIV-1 subtypes present in Polish population and their evolution. Complete protease and part of reverse transcriptase regions were sequenced from the sera of patients directed to the laboratory for drug resistance testing. The Stanford's HIVdb program was used for the interpretation of results and subtyping. The variants scoring at least "intermediate resistance" for at least one drug were considered as resistant. The results obtained were compared to those obtained in the years 2000-2007. A total of 95 patients were enrolled in the 2008 study. Homosexual transmission of infection was documented in more than 55% of all cases. The overall prevalence of transmitted drug resistance (TDR) was 5.3% (3.9% in 2007, 5.8% in 2006, and 14.1% in the years 2002-2005). The study from the years 2000 to 2001 revealed 28.7% prevalence. Preliminary analysis of the first half of 2009 shows the ratio of 7.8%. In four (4.2%) cases drug resistance was associated with protease inhibitors class, in one case (1.1%) with resistance to non-nucleoside reverse transcriptase inhibitors class. In four cases (4.2%) non-B subtype was identified (C, G, CRF01_AE, CRF02_AG). An increase of percentage of drug resistant mutants-from 3.9% (2007) to 5.3% (2008)-was recognized. In this study, TDR was limited to single classes of antiretroviral drugs. HIV-1 subtype B prevails in Poland. PMID:20513098

  15. A Qualitative Study of Barriers to Consistent Condom Use among HIV-1 Serodiscordant Couples in Kenya

    PubMed Central

    Ngure, Kenneth; Mugo, Nelly; Celum, Connie; Baeten, Jared M.; Morris, Martina; Olungah, Owuor; Olenja, Joyce; Tamooh, Harrison; Shell-Duncan, Bettina

    2014-01-01

    This study explored barriers to consistent condom use among heterosexual HIV-1 serodiscordant couples who were aware of the HIV-1 serodiscordant status and had been informed about condom use as a risk reduction strategy. We conducted 28 in-depth interviews and 9 focus group discussions among purposively-selected heterosexual HIV-1 serodiscordant couples from Thika and Nairobi districts in Kenya. We analyzed the transcribed data with a grounded theory approach. The most common barriers to consistent condom use included male partners’ reluctance to use condoms regardless of HIV-1 status coupled with female partners’ inability to negotiate condom use, misconceptions about HIV-1 serodiscordance, and desire for children. Specific areas of focus should include development of skills for women to effectively negotiate condom use, ongoing information on HIV-1 serodiscordance and education on safer conception practices that minimize risk of HIV-1 transmission. PMID:22085306

  16. Prevalence of Transmitted Drug Resistance and Impact of Transmitted Resistance on Treatment Success in the German HIV-1 Seroconverter Cohort

    PubMed Central

    Houareau, Claudia; Werning, Johanna; Keeren, Kathrin; Somogyi, Sybille; Kollan, Christian; Jessen, Heiko; Dupke, Stephan; Hamouda, Osamah

    2010-01-01

    Background The aim of this study is to analyse the prevalence of transmitted drug resistance, TDR, and the impact of TDR on treatment success in the German HIV-1 Seroconverter Cohort. Methods Genotypic resistance analysis was performed in treatment-naïve study patients whose sample was available 1,312/1,564 (83.9% October 2008). A genotypic resistance result was obtained for 1,276/1,312 (97.3%). The resistance associated mutations were identified according to the surveillance drug resistance mutations list recommended for drug-naïve patients. Treatment success was determined as viral suppression below 500 copies/ml. Results Prevalence of TDR was stable at a high level between 1996 and 2007 in the German HIV-1 Seroconverter Cohort (N = 158/1,276; 12.4%; CIwilson 10.7–14.3; p for trend = 0.25). NRTI resistance was predominant (7.5%) but decreased significantly over time (CIWilson: 6.2–9.1, p for trend = 0.02). NNRTI resistance tended to increase over time (NNRTI: 3.5%; CIWilson: 2.6–4.6; p for trend  = 0.07), whereas PI resistance remained stable (PI: 3.0%; CIWilson: 2.1–4.0; p for trend  = 0.24). Resistance to all drug classes was frequently caused by singleton resistance mutations (NRTI 55.6%, PI 68.4%, NNRTI 99.1%). The majority of NRTI-resistant strains (79.8%) carried resistance-associated mutations selected by the thymidine analogues zidovudine and stavudine. Preferably 2NRTI/1PIr combinations were prescribed as first line regimen in patients with resistant HIV as well as in patients with susceptible strains (susceptible 45.3%; 173/382 vs. resistant 65.5%; 40/61). The majority of patients in both groups were treated successfully within the first year after ART-initiation (susceptible: 89.9%; 62/69; resistant: 7/9; 77.8%). Conclusion Overall prevalence of TDR remained stable at a high level but trends of resistance against drug classes differed over time. The significant decrease of NRTI-resistance in patients newly infected with

  17. Identification of full-length transmitted/founder viruses and their progeny in primary HIV-1 infection

    SciTech Connect

    Korber, Bette; Hraber, Peter; Giorgi, Elena; Bhattacharya, T

    2009-01-01

    Identification of transmitted/founder virus genomes and their progeny by is a novel strategy for probing the molecular basis of HIV-1 transmission and for evaluating the genetic imprint of viral and host factors that act to constrain or facilitate virus replication. Here, we show in a cohort of twelve acutely infected subjects (9 clade B; 3 clade C), that complete genomic sequences of transmitted/founder viruses could be inferred using single genome amplification of plasma viral RNA, direct amplicon sequencing, and a model of random virus evolution. This allowed for the precise identification, chemical synthesis, molecular cloning, and biological analysis of those viruses actually responsible for productive clinical infection and for a comprehensive mapping of sequential viral genomes and proteomes for mutations that are necessary or incidental to the establishment of HIV-1 persistence. Transmitted/founder viruses were CD4 and CCR5 tropic, replicated preferentially in activated primary T-Iymphocytes but not monocyte-derived macrophages, and were effectively shielded from most heterologous or broadly neutralizing antibodies. By 3 months of infection, the evolving viral quasispecies in three subjects showed mutational fixation at only 2-5 discreet genomic loci. By 6-12 months, mutational fixation was evident at 18-27 genomic loci. Some, but not all, of these mutations were attributable to virus escape from cytotoxic Tlymphocytes or neutralizing antibodies, suggesting that other viral or host factors may influence early HIV -1 fitness.

  18. Balance between transmitted HLA preadapted and nonassociated polymorphisms is a major determinant of HIV-1 disease progression.

    PubMed

    Mónaco, Daniela C; Dilernia, Dario A; Fiore-Gartland, Andrew; Yu, Tianwei; Prince, Jessica L; Dennis, Kristine K; Qin, Kai; Schaefer, Malinda; Claiborne, Daniel T; Kilembe, William; Tang, Jianming; Price, Matt A; Farmer, Paul; Gilmour, Jill; Bansal, Anju; Allen, Susan; Goepfert, Paul; Hunter, Eric

    2016-09-19

    HIV-1 adapts to a new host through mutations that facilitate immune escape. Here, we evaluate the impact on viral control and disease progression of transmitted polymorphisms that were either preadapted to or nonassociated with the new host's HLA. In a cohort of 169 Zambian heterosexual transmission pairs, we found that almost one-third of possible HLA-linked target sites in the transmitted virus Gag protein are already adapted, and that this transmitted preadaptation significantly reduced early immune recognition of epitopes. Transmitted preadapted and nonassociated polymorphisms showed opposing effects on set-point VL and the balance between the two was significantly associated with higher set-point VLs in a multivariable model including other risk factors. Transmitted preadaptation was also significantly associated with faster CD4 decline (<350 cells/µl) and this association was stronger after accounting for nonassociated polymorphisms, which were linked with slower CD4 decline. Overall, the relative ratio of the two classes of polymorphisms was found to be the major determinant of CD4 decline in a multivariable model including other risk factors. This study reveals that, even before an immune response is mounted in the new host, the balance of these opposing factors can significantly influence the outcome of HIV-1 infection.

  19. Balance between transmitted HLA preadapted and nonassociated polymorphisms is a major determinant of HIV-1 disease progression.

    PubMed

    Mónaco, Daniela C; Dilernia, Dario A; Fiore-Gartland, Andrew; Yu, Tianwei; Prince, Jessica L; Dennis, Kristine K; Qin, Kai; Schaefer, Malinda; Claiborne, Daniel T; Kilembe, William; Tang, Jianming; Price, Matt A; Farmer, Paul; Gilmour, Jill; Bansal, Anju; Allen, Susan; Goepfert, Paul; Hunter, Eric

    2016-09-19

    HIV-1 adapts to a new host through mutations that facilitate immune escape. Here, we evaluate the impact on viral control and disease progression of transmitted polymorphisms that were either preadapted to or nonassociated with the new host's HLA. In a cohort of 169 Zambian heterosexual transmission pairs, we found that almost one-third of possible HLA-linked target sites in the transmitted virus Gag protein are already adapted, and that this transmitted preadaptation significantly reduced early immune recognition of epitopes. Transmitted preadapted and nonassociated polymorphisms showed opposing effects on set-point VL and the balance between the two was significantly associated with higher set-point VLs in a multivariable model including other risk factors. Transmitted preadaptation was also significantly associated with faster CD4 decline (<350 cells/µl) and this association was stronger after accounting for nonassociated polymorphisms, which were linked with slower CD4 decline. Overall, the relative ratio of the two classes of polymorphisms was found to be the major determinant of CD4 decline in a multivariable model including other risk factors. This study reveals that, even before an immune response is mounted in the new host, the balance of these opposing factors can significantly influence the outcome of HIV-1 infection. PMID:27551154

  20. Bacterial Vaginosis Associated with Increased Risk of Female-to-Male HIV-1 Transmission: A Prospective Cohort Analysis among African Couples

    PubMed Central

    Cohen, Craig R.; Lingappa, Jairam R.; Baeten, Jared M.; Ngayo, Musa O.; Spiegel, Carol A.; Hong, Ting; Donnell, Deborah; Celum, Connie; Kapiga, Saidi; Delany, Sinead; Bukusi, Elizabeth A.

    2012-01-01

    Background Bacterial vaginosis (BV), a disruption of the normal vaginal flora, has been associated with a 60% increased risk of HIV-1 acquisition in women and higher concentration of HIV-1 RNA in the genital tract of HIV-1–infected women. However, whether BV, which is present in up to half of African HIV-1–infected women, is associated with an increase in HIV-1 transmission to male partners has not been assessed in previous studies. Methods and Findings We assessed the association between BV on female-to-male HIV-1 transmission risk in a prospective study of 2,236 HIV-1–seropositive women and their HIV-1 uninfected male partners from seven African countries from a randomized placebo-controlled trial that enrolled heterosexual African adults who were seropositive for both HIV-1 and herpes simplex virus (HSV)-2, and their HIV-1–seronegative partners. Participants were followed for up to 24 months; every three months, vaginal swabs were obtained from female partners for Gram stain and male partners were tested for HIV-1. BV and normal vaginal flora were defined as a Nugent score of 7–10 and 0–3, respectively. To reduce misclassification, HIV-1 sequence analysis of viruses from seroconverters and their partners was performed to determine linkage of HIV-1 transmissions. Overall, 50 incident HIV-1 infections occurred in men in which the HIV-1–infected female partner had an evaluable vaginal Gram stain. HIV-1 incidence in men whose HIV-1–infected female partners had BV was 2.91 versus 0.76 per 100 person-years in men whose female partners had normal vaginal flora (hazard ratio 3.62, 95% CI 1.74–7.52). After controlling for sociodemographic factors, sexual behavior, male circumcision, sexually transmitted infections, pregnancy, and plasma HIV-1 RNA levels in female partners, BV was associated with a greater than 3-fold increased risk of female-to-male HIV-1 transmission (adjusted hazard ratio 3.17, 95% CI 1.37–7.33). Conclusions This study identified an

  1. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization

    PubMed Central

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S.; Giorgi, Elena E.; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J.; Wagh, Kshitij; Carey, Brittany R.; Gao, Hongmei; Greene, Kelli M.; Tang, Haili; Marais, Jinny C.; Diphoko, Thabo E.; Hraber, Peter; Tumba, Nancy; Moore, Penny L.; Gray, Glenda E.; Kublin, James; McElrath, M. Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L.; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H.; Hahn, Beatrice H.; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C.; Williamson, Carolyn

    2016-01-01

    The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 μg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre

  2. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization.

    PubMed

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S; Giorgi, Elena E; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J; Wagh, Kshitij; Garrity, Jetta; Carey, Brittany R; Gao, Hongmei; Greene, Kelli M; Tang, Haili; Bandawe, Gama P; Marais, Jinny C; Diphoko, Thabo E; Hraber, Peter; Tumba, Nancy; Moore, Penny L; Gray, Glenda E; Kublin, James; McElrath, M Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H; Hahn, Beatrice H; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C; Williamson, Carolyn

    2016-07-01

    The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 μg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre

  3. Sexually-Transmitted/Founder HIV-1 Cannot Be Directly Predicted from Plasma or PBMC-Derived Viral Quasispecies in the Transmitting Partner

    PubMed Central

    Frange, Pierre; Meyer, Laurence; Jung, Matthieu; Goujard, Cecile; Zucman, David; Abel, Sylvie; Hochedez, Patrick; Gousset, Marine; Gascuel, Olivier; Rouzioux, Christine; Chaix, Marie-Laure

    2013-01-01

    Objective Characterization of HIV-1 sequences in newly infected individuals is important for elucidating the mechanisms of viral sexual transmission. We report the identification of transmitted/founder viruses in eight pairs of HIV-1 sexually-infected patients enrolled at the time of primary infection (“recipients”) and their transmitting partners (“donors”). Methods Using a single genome-amplification approach, we compared quasispecies in donors and recipients on the basis of 316 and 376 C2V5 env sequences amplified from plasma viral RNA and PBMC-associated DNA, respectively. Results Both DNA and RNA sequences indicated very homogeneous viral populations in all recipients, suggesting transmission of a single variant, even in cases of recent sexually transmitted infections (STIs) in donors (n = 2) or recipients (n = 3). In all pairs, the transmitted/founder virus was derived from an infrequent variant population within the blood of the donor. The donor variant sequences most closely related to the recipient sequences were found in plasma samples in 3/8 cases and/or in PBMC samples in 6/8 cases. Although donors were exclusively (n = 4) or predominantly (n = 4) infected by CCR5-tropic (R5) strains, two recipients were infected with highly homogeneous CXCR4/dual-mixed-tropic (X4/DM) viral populations, identified in both DNA and RNA. The proportion of X4/DM quasispecies in donors was higher in cases of X4/DM than R5 HIV transmission (16.7–22.0% versus 0–2.6%), suggesting that X4/DM transmission may be associated with a threshold population of X4/DM circulating quasispecies in donors. Conclusions These suggest that a severe genetic bottleneck occurs during subtype B HIV-1 heterosexual and homosexual transmission. Sexually-transmitted/founder virus cannot be directly predicted by analysis of the donor’s quasispecies in plasma and/or PBMC. Additional studies are required to fully understand the traits that confer the capacity to transmit and

  4. Transmitted Virus Fitness and Host T Cell Responses Collectively Define Divergent Infection Outcomes in Two HIV-1 Recipients

    PubMed Central

    Yue, Ling; Pfafferott, Katja J.; Baalwa, Joshua; Conrod, Karen; Dong, Catherine C.; Chui, Cecilia; Rong, Rong; Claiborne, Daniel T.; Prince, Jessica L.; Tang, Jianming; Ribeiro, Ruy M.; Cormier, Emmanuel; Hahn, Beatrice H.; Perelson, Alan S.; Shaw, George M.; Karita, Etienne; Gilmour, Jill; Goepfert, Paul; Derdeyn, Cynthia A.; Allen, Susan A.; Borrow, Persephone; Hunter, Eric

    2015-01-01

    Control of virus replication in HIV-1 infection is critical to delaying disease progression. While cellular immune responses are a key determinant of control, relatively little is known about the contribution of the infecting virus to this process. To gain insight into this interplay between virus and host in viral control, we conducted a detailed analysis of two heterosexual HIV-1 subtype A transmission pairs in which female recipients sharing three HLA class I alleles exhibited contrasting clinical outcomes: R880F controlled virus replication while R463F experienced high viral loads and rapid disease progression. Near full-length single genome amplification defined the infecting transmitted/founder (T/F) virus proteome and subsequent sequence evolution over the first year of infection for both acutely infected recipients. T/F virus replicative capacities were compared in vitro, while the development of the earliest cellular immune response was defined using autologous virus sequence-based peptides. The R880F T/F virus replicated significantly slower in vitro than that transmitted to R463F. While neutralizing antibody responses were similar in both subjects, during acute infection R880F mounted a broad T cell response, the most dominant components of which targeted epitopes from which escape was limited. In contrast, the primary HIV-specific T cell response in R463F was focused on just two epitopes, one of which rapidly escaped. This comprehensive study highlights both the importance of the contribution of the lower replication capacity of the transmitted/founder virus and an associated induction of a broad primary HIV-specific T cell response, which was not undermined by rapid epitope escape, to long-term viral control in HIV-1 infection. It underscores the importance of the earliest CD8 T cell response targeting regions of the virus proteome that cannot mutate without a high fitness cost, further emphasizing the need for vaccines that elicit a breadth of T cell

  5. Transmitted virus fitness and host T cell responses collectively define divergent infection outcomes in two HIV-1 recipients

    DOE PAGES

    Yue, Ling; Pfafferott, Katja J.; Baalwa, Joshua; Conrod, Karen; Dong, Catherine C.; Chui, Cecilia; Rong, Rong; Claiborne, Daniel T.; Prince, Jessica L.; Tang, Jianming; et al

    2015-01-08

    Control of virus replication in HIV-1 infection is critical to delaying disease progression. While cellular immune responses are a key determinant of control, relatively little is known about the contribution of the infecting virus to this process. To gain insight into this interplay between virus and host in viral control, we conducted a detailed analysis of two heterosexual HIV-1 subtype A transmission pairs in which female recipients sharing three HLA class I alleles exhibited contrasting clinical outcomes: R880F controlled virus replication while R463F experienced high viral loads and rapid disease progression. Near full-length single genome amplification defined the infecting transmitted/foundermore » (T/F) virus proteome and subsequent sequence evolution over the first year of infection for both acutely infected recipients. T/F virus replicative capacities were compared in vitro, while the development of the earliest cellular immune response was defined using autologous virus sequence-based peptides. The R880F T/F virus replicated significantly slower in vitro than that transmitted to R463F. While neutralizing antibody responses were similar in both subjects, during acute infection R880F mounted a broad T cell response, the most dominant components of which targeted epitopes from which escape was limited. In contrast, the primary HIV-specific T cell response in R463F was focused on just two epitopes, one of which rapidly escaped. This comprehensive study highlights both the importance of the contribution of the lower replication capacity of the transmitted/founder virus and an associated induction of a broad primary HIV-specific T cell response, which was not undermined by rapid epitope escape, to long-term viral control in HIV-1 infection. It underscores the importance of the earliest CD8 T cell response targeting regions of the virus proteome that cannot mutate without a high fitness cost, further emphasizing the need for vaccines that elicit a breadth of

  6. Transmitted virus fitness and host T cell responses collectively define divergent infection outcomes in two HIV-1 recipients

    SciTech Connect

    Yue, Ling; Pfafferott, Katja J.; Baalwa, Joshua; Conrod, Karen; Dong, Catherine C.; Chui, Cecilia; Rong, Rong; Claiborne, Daniel T.; Prince, Jessica L.; Tang, Jianming; Ribeiro, Ruy M.; Cormier, Emmanuel; Hahn, Beatrice H.; Perelson, Alan S.; Shaw, George M.; Karita, Etienne; Gilmour, Jill; Goepfert, Paul; Derdeyn, Cynthia A.; Allen, Susan A.; Borrow, Persephone; Hunter, Eric; Douek, Daniel C.

    2015-01-08

    Control of virus replication in HIV-1 infection is critical to delaying disease progression. While cellular immune responses are a key determinant of control, relatively little is known about the contribution of the infecting virus to this process. To gain insight into this interplay between virus and host in viral control, we conducted a detailed analysis of two heterosexual HIV-1 subtype A transmission pairs in which female recipients sharing three HLA class I alleles exhibited contrasting clinical outcomes: R880F controlled virus replication while R463F experienced high viral loads and rapid disease progression. Near full-length single genome amplification defined the infecting transmitted/founder (T/F) virus proteome and subsequent sequence evolution over the first year of infection for both acutely infected recipients. T/F virus replicative capacities were compared in vitro, while the development of the earliest cellular immune response was defined using autologous virus sequence-based peptides. The R880F T/F virus replicated significantly slower in vitro than that transmitted to R463F. While neutralizing antibody responses were similar in both subjects, during acute infection R880F mounted a broad T cell response, the most dominant components of which targeted epitopes from which escape was limited. In contrast, the primary HIV-specific T cell response in R463F was focused on just two epitopes, one of which rapidly escaped. This comprehensive study highlights both the importance of the contribution of the lower replication capacity of the transmitted/founder virus and an associated induction of a broad primary HIV-specific T cell response, which was not undermined by rapid epitope escape, to long-term viral control in HIV-1 infection. It underscores the importance of the earliest CD8 T cell response targeting regions of the virus proteome that cannot mutate without a high fitness cost, further emphasizing the need for vaccines that elicit a

  7. Transmitted Drug Resistance Mutations in Antiretroviral-Naïve Injection Drug Users with Chronic HIV-1 Infection in Iran

    PubMed Central

    Memarnejadian, Arash; Menbari, Shahoo; Vahabpour, Rouhollah; Aghasadeghi, Mohammad Reza; Mostafavi, Ehsan; Abdi, Mohammad

    2015-01-01

    The growing incidence and transmission of drug resistant HIV-1 strains due to widespread use of antiretroviral therapy (ART) can jeopardize the success of first-line ART. While there is a known moderate prevalence of transmitted drug resistance (TDR) among newly infected Iranians, no data exist about the rate of these primary resistance mutations among the ART-naïve, chronically infected individuals who are, in fact, the main candidates for ART initiation. To address this issue, we collected blood samples from 40 ART-naïve injection drug-users (IDUs) with chronic HIV-1 infection (seroconversion time ranging from 2 to 9 years) living in Sanandaj, Iran, followed by sequencing of the protease and reverse-transcriptase regions from their HIV-1 genome. Phylogenetic analyses of the sequenced regions revealed that all samples were CRF35_AD. Transmitted resistance mutations were interpreted as surveillance drug-resistant mutations (SDRMs) based on the world health organization (WHO) algorithm. The frequency of SDRMs to any class of antiretroviral drugs was 15%, which included mutations to nucleoside reverse transcriptase inhibitors (NRTIs, 10%), with M41L and M184V as the most common (5%), and non-nucleoside reverse transcriptase inhibitors (NNRTIs, 5%), with K103N as the only detected mutation (5%). Although not in the WHO SDRMs list, several minor protease inhibitor resistant mutations listed in the International Antiviral Society-USA panel were identified, of which M36I, H69K, L89M/V/I (each one 100%) and K20R/T (92.5%) can be considered as polymorphic signatures for CRF35_AD.The relatively high rate of TDR mutations in our study raises concerns about the risk of treatment failure in chronically infected IDUs of Sanandaj city. These results suggest that routine resistance testing should be considered before the therapy initiation in this area. Additional surveillance studies are required to generalize this deduction to other cities of Iran. PMID:25962088

  8. Transmitted Drug Resistance Mutations in Antiretroviral-Naïve Injection Drug Users with Chronic HIV-1 Infection in Iran.

    PubMed

    Memarnejadian, Arash; Menbari, Shahoo; Mansouri, Seyed Ali; Sadeghi, Leila; Vahabpour, Rouhollah; Aghasadeghi, Mohammad Reza; Mostafavi, Ehsan; Abdi, Mohammad

    2015-01-01

    The growing incidence and transmission of drug resistant HIV-1 strains due to widespread use of antiretroviral therapy (ART) can jeopardize the success of first-line ART. While there is a known moderate prevalence of transmitted drug resistance (TDR) among newly infected Iranians, no data exist about the rate of these primary resistance mutations among the ART-naïve, chronically infected individuals who are, in fact, the main candidates for ART initiation. To address this issue, we collected blood samples from 40 ART-naïve injection drug-users (IDUs) with chronic HIV-1 infection (seroconversion time ranging from 2 to 9 years) living in Sanandaj, Iran, followed by sequencing of the protease and reverse-transcriptase regions from their HIV-1 genome. Phylogenetic analyses of the sequenced regions revealed that all samples were CRF35_AD. Transmitted resistance mutations were interpreted as surveillance drug-resistant mutations (SDRMs) based on the world health organization (WHO) algorithm. The frequency of SDRMs to any class of antiretroviral drugs was 15%, which included mutations to nucleoside reverse transcriptase inhibitors (NRTIs, 10%), with M41L and M184V as the most common (5%), and non-nucleoside reverse transcriptase inhibitors (NNRTIs, 5%), with K103N as the only detected mutation (5%). Although not in the WHO SDRMs list, several minor protease inhibitor resistant mutations listed in the International Antiviral Society-USA panel were identified, of which M36I, H69K, L89M/V/I (each one 100%) and K20R/T (92.5%) can be considered as polymorphic signatures for CRF35_AD.The relatively high rate of TDR mutations in our study raises concerns about the risk of treatment failure in chronically infected IDUs of Sanandaj city. These results suggest that routine resistance testing should be considered before the therapy initiation in this area. Additional surveillance studies are required to generalize this deduction to other cities of Iran. PMID:25962088

  9. The prevalence of HSV-2 infection in HIV-1 discordant couples.

    PubMed

    Duan, S; Ding, Y; Wu, Z; Rou, K; Yang, Y; Wang, J; Gao, M; Ye, R; Xiang, L; He, N

    2016-01-01

    We aimed to investigate the prevalence and associated factors of HSV-2 discordance and concordance in HIV-1-discordant couples. This study used the baseline data from a cohort study of HIV-1-discordant couples in Dehong prefecture of Yunnan province, China. Of 954 participating couples, 42·4% were affected by HSV-2, of which 20·4% were HSV-2-concordant positive, 7·6% were HSV-2-discordant where the male was HSV-2 positive, and 14·4% were HSV-2 discordant where the female was HSV-2 positive. Compared to HSV-2-negative concordance, HSV-2 discordance with an HSV-2-positive male spouse was significantly associated with characteristics of the male spouse, including Han ethnicity and being in a second marriage. HSV-2 discordance with an HSV-2-positive female spouse was significantly associated with characteristics of the female spouse, including Han ethnicity, having engaged in commercial sex, having a sexual relationship of <3 years and being HIV-1 infected. Compared to HSV-2 discordance, HSV-2-positive concordance was significantly associated with an education level of middle school or higher for both spouses, a sexual relationship of ⩾3 years, more frequent sex and having an HIV-1-infected male spouse. The findings highlight the need for HSV-2 prevention and treatment efforts to reduce HSV-2 transmission in this population, and emphasize the importance of implementing prevention interventions early in couples' relationships.

  10. HIV-1 Genetic Diversity and Transmitted Drug Resistance Among Recently Infected Individuals at Men Who Have Sex with Men Sentinel Surveillance Points in Hebei Province, China.

    PubMed

    Lu, Xinli; Kang, Xianjiang; Chen, Suliang; Zhao, Hongru; Liu, Yongjian; Zhao, Cuiying; Zhang, Yuqi; Li, Jingyun; Cui, Ze; Wang, Xianfeng

    2015-10-01

    For this study, 50 HIV-1 plasma samples of recently infected men who have sex with men (MSM) were amplified and sequenced. Multiple subtypes were identified by phylogenetic analyses of HIV-1 gag, env, and pol gene regions, including CRF01_AE (56.0%), CRF07_BC (30.0%), subtype B (12.0%), and unique recombinant forms (URFs, 6.0%). CRF01_AE was the most frequent genotype in the epidemic. Three recombination patterns of URFs were identified: 01BC, 01B, and 01C. The rate of HIV-1 transmitted drug resistance (TDR) mutation (M46L) was 2.08% (1/48). URFs and TDR first identified in this study suggest that HIV-1 prevalence is more and more complicated, and HIV-1 drug-resistant strains have begun to spread among at risk populations in Hebei. Our findings can provide vital information for an efficient surveillance system and strategic HIV prevention and control measures in China by revealing the evolutionary status and HIV-1 TDR of HIV-1 strains among recently infected MSM in Hebei Province.

  11. HIV-1 Genetic Diversity and Transmitted Drug Resistance Among Recently Infected Individuals at Men Who Have Sex with Men Sentinel Surveillance Points in Hebei Province, China.

    PubMed

    Lu, Xinli; Kang, Xianjiang; Chen, Suliang; Zhao, Hongru; Liu, Yongjian; Zhao, Cuiying; Zhang, Yuqi; Li, Jingyun; Cui, Ze; Wang, Xianfeng

    2015-10-01

    For this study, 50 HIV-1 plasma samples of recently infected men who have sex with men (MSM) were amplified and sequenced. Multiple subtypes were identified by phylogenetic analyses of HIV-1 gag, env, and pol gene regions, including CRF01_AE (56.0%), CRF07_BC (30.0%), subtype B (12.0%), and unique recombinant forms (URFs, 6.0%). CRF01_AE was the most frequent genotype in the epidemic. Three recombination patterns of URFs were identified: 01BC, 01B, and 01C. The rate of HIV-1 transmitted drug resistance (TDR) mutation (M46L) was 2.08% (1/48). URFs and TDR first identified in this study suggest that HIV-1 prevalence is more and more complicated, and HIV-1 drug-resistant strains have begun to spread among at risk populations in Hebei. Our findings can provide vital information for an efficient surveillance system and strategic HIV prevention and control measures in China by revealing the evolutionary status and HIV-1 TDR of HIV-1 strains among recently infected MSM in Hebei Province. PMID:26200883

  12. Impact of immune escape mutations on HIV-1 fitness in the context of the cognate transmitted/founder genome

    PubMed Central

    2012-01-01

    Background A modest change in HIV-1 fitness can have a significant impact on viral quasispecies evolution and viral pathogenesis, transmission and disease progression. To determine the impact of immune escape mutations selected by cytotoxic T lymphocytes (CTL) on viral fitness in the context of the cognate transmitted/founder (T/F) genome, we developed a new competitive fitness assay using molecular clones of T/F genomes lacking exogenous genetic markers and a highly sensitive and precise parallel allele-specific sequencing (PASS) method. Results The T/F and mutant viruses were competed in CD4+ T-cell enriched cultures, relative proportions of viruses were assayed after repeated cell-free passage, and fitness costs were estimated by mathematical modeling. Naturally occurring HLA B57-restricted mutations involving the TW10 epitope in Gag and two epitopes in Tat/Rev and Env were assessed independently and together. Compensatory mutations which restored viral replication fitness were also assessed. A principal TW10 escape mutation, T242N, led to a 42% reduction in replication fitness but V247I and G248A mutations in the same epitope restored fitness to wild-type levels. No fitness difference was observed between the T/F and a naturally selected variant carrying the early CTL escape mutation (R355K) in Env and a reversion mutation in the Tat/Rev overlapping region. Conclusions These findings reveal a broad spectrum of fitness costs to CTL escape mutations in T/F viral genomes, similar to recent findings reported for neutralizing antibody escape mutations, and highlight the extraordinary plasticity and adaptive potential of the HIV-1 genome. Analysis of T/F genomes and their evolved progeny is a powerful approach for assessing the impact of composite mutational events on viral fitness. PMID:23110705

  13. Transmitted Drug Resistance in Persons with Acute/Early HIV-1 in San Francisco, 2002-2009

    PubMed Central

    Jain, Vivek; Liegler, Teri; Vittinghoff, Eric; Hartogensis, Wendy; Bacchetti, Peter; Poole, Lauren; Loeb, Lisa; Pilcher, Christopher D.; Grant, Robert M.; Deeks, Steven G.; Hecht, Frederick M.

    2010-01-01

    Background Transmitted HIV-1 drug resistance (TDR) is an ongoing public health problem, representing 10–20% of new HIV infections in many geographic areas. TDR usually arises from two main sources: individuals on antiretroviral therapy (ART) who are failing to achieve virologic suppression, and individuals who acquired TDR and transmit it while still ART-naïve. TDR rates can be impacted when novel antiretroviral medications are introduced that allow for greater virologic suppression of source patients. Although several new HIV medications were introduced starting in late 2007, including raltegravir, maraviroc, and etravirine, it is not known whether the prevalence of TDR was subsequently affected in 2008–2009. Methodology/Principal Findings We performed population sequence genotyping on individuals who were diagnosed with acute or early HIV (<6 months duration) and who enrolled in the Options Project, a prospective cohort, between 2002 and 2009. We used logistic regression to compare the odds of acquiring drug-resistant HIV before versus after the arrival of new ART (2005–2007 vs. 2008–2009). From 2003–2007, TDR rose from 7% to 24%. Prevalence of TDR was then 15% in 2008 and in 2009. While the odds of acquiring TDR were lower in 2008–2009 compared to 2005–2007, this was not statistically significant (odds ratio 0.65, 95% CI 0.31–1.38; p = 0.27). Conclusions Our study suggests that transmitted drug resistance rose from 2003–2007, but this upward trend did not continue in 2008 and 2009. Nevertheless, the TDR prevalence in 2008–2009 remained substantial, emphasizing that improved management strategies for drug-resistant HIV are needed if TDR is to be further reduced. Continued surveillance for TDR will be important in understanding the full impact of new antiretroviral medications. PMID:21170322

  14. The initial antibody response to HIV-1: induction of ineffective early B cell responses against GP41 by the transmitted/founder virus

    SciTech Connect

    Chavez, Leslie L; Perelson, Alan

    2008-01-01

    A window of opportunity for immune responses to extinguish HIV -1 exists from the moment of transmission through establishment of the latent pool of HIV -I-infected cells. A critical time to study the initial immune responses to the transmitted/founder virus is the eclipse phase of HIV-1 infection (time from transmission to the first appearance of plasma virus) but, to date, this period has been logistically difficult to analyze. Studies in non-human primates challenged with chimeric simianhuman immunodeficiency virus have shown that neutralizing antibodies, when present at the time of infection, can prevent virus infection.

  15. Replicative fitness of transmitted HIV-1 drives acute immune activation, proviral load in memory CD4+ T cells, and disease progression.

    PubMed

    Claiborne, Daniel T; Prince, Jessica L; Scully, Eileen; Macharia, Gladys; Micci, Luca; Lawson, Benton; Kopycinski, Jakub; Deymier, Martin J; Vanderford, Thomas H; Nganou-Makamdop, Krystelle; Ende, Zachary; Brooks, Kelsie; Tang, Jianming; Yu, Tianwei; Lakhi, Shabir; Kilembe, William; Silvestri, Guido; Douek, Daniel; Goepfert, Paul A; Price, Matthew A; Allen, Susan A; Paiardini, Mirko; Altfeld, Marcus; Gilmour, Jill; Hunter, Eric

    2015-03-24

    HIV-1 infection is characterized by varying degrees of chronic immune activation and disruption of T-cell homeostasis, which impact the rate of disease progression. A deeper understanding of the factors that influence HIV-1-induced immunopathology and subsequent CD4(+) T-cell decline is critical to strategies aimed at controlling or eliminating the virus. In an analysis of 127 acutely infected Zambians, we demonstrate a dramatic and early impact of viral replicative capacity (vRC) on HIV-1 immunopathogenesis that is independent of viral load (VL). Individuals infected with high-RC viruses exhibit a distinct inflammatory cytokine profile as well as significantly elevated T-cell activation, proliferation, and CD8(+) T-cell exhaustion, during the earliest months of infection. Moreover, the vRC of the transmitted virus is positively correlated with the magnitude of viral burden in naive and central memory CD4(+) T-cell populations, raising the possibility that transmitted viral phenotypes may influence the size of the initial latent viral reservoir. Taken together, these findings support an unprecedented role for the replicative fitness of the founder virus, independent of host protective genes and VL, in influencing multiple facets of HIV-1-related immunopathology, and that a greater focus on this parameter could provide novel approaches to clinical interventions.

  16. Primary human epithelial cell culture system for studying interactions between female upper genital tract and sexually transmitted viruses, HSV-2 and HIV-1.

    PubMed

    Kaushic, Charu; Nazli, Aisha; Ferreira, Victor H; Kafka, Jessica K

    2011-10-01

    Evidence from clinical and epidemiological studies indicates that women are disproportionately susceptible to sexually transmitted viral infections. To understand the underlying biological basis for this increased susceptibility, more studies are needed to examine the acute events in the female reproductive tract following exposure to viruses during sexual transmission. The epithelial lining of the female reproductive tract is the primary barrier that sexually transmitted viruses, such as HIV-1 and HSV-2 need to infect or traverse, in order to initiate and establish productive infection. We have established an ex-vivo primary culture system to grow genital epithelial cells from upper reproductive tract tissues of women. Using these cultures, we have extensively examined the interactions between epithelial cells of the female genital tract and HSV-2 and HIV-1. In this review, we describe in detail the experimental protocol to grow these cultures, monitor their differentiation and inoculate with HSV-2 and HIV-1. Prospective use of these cultures to re-create the microenvironment in the reproductive tract is discussed.

  17. HIV-1 transmission linkage in an HIV-1 prevention clinical trial

    SciTech Connect

    Leitner, Thomas; Campbell, Mary S; Mullins, James I; Hughes, James P; Wong, Kim G; Raugi, Dana N; Scrensen, Stefanie

    2009-01-01

    HIV-1 sequencing has been used extensively in epidemiologic and forensic studies to investigate patterns of HIV-1 transmission. However, the criteria for establishing genetic linkage between HIV-1 strains in HIV-1 prevention trials have not been formalized. The Partners in Prevention HSV/HIV Transmission Study (ClinicaITrials.gov NCT00194519) enrolled 3408 HIV-1 serodiscordant heterosexual African couples to determine the efficacy of genital herpes suppression with acyclovir in reducing HIV-1 transmission. The trial analysis required laboratory confirmation of HIV-1 linkage between enrolled partners in couples in which seroconversion occurred. Here we describe the process and results from HIV-1 sequencing studies used to perform transmission linkage determination in this clinical trial. Consensus Sanger sequencing of env (C2-V3-C3) and gag (p17-p24) genes was performed on plasma HIV-1 RNA from both partners within 3 months of seroconversion; env single molecule or pyrosequencing was also performed in some cases. For linkage, we required monophyletic clustering between HIV-1 sequences in the transmitting and seroconverting partners, and developed a Bayesian algorithm using genetic distances to evaluate the posterior probability of linkage of participants sequences. Adjudicators classified transmissions as linked, unlinked, or indeterminate. Among 151 seroconversion events, we found 108 (71.5%) linked, 40 (26.5%) unlinked, and 3 (2.0%) to have indeterminate transmissions. Nine (8.3%) were linked by consensus gag sequencing only and 8 (7.4%) required deep sequencing of env. In this first use of HIV-1 sequencing to establish endpoints in a large clinical trial, more than one-fourth of transmissions were unlinked to the enrolled partner, illustrating the relevance of these methods in the design of future HIV-1 prevention trials in serodiscordant couples. A hierarchy of sequencing techniques, analysis methods, and expert adjudication contributed to the linkage

  18. Moderate prevalence of transmitted drug resistance and high HIV-1 genetic diversity in patients from Mato Grosso State, Central Western Brazil.

    PubMed

    Ferreira, Adriana Santarém; Cardoso, Ludimila Paula Vaz; Stefani, Mariane Martins de Araújo

    2011-08-01

    Few reports have described the molecular characteristics of the AIDS epidemic within the interior regions of Brazil, a country of continental dimensions. To help fill this gap, the prevalence of transmitted antiretroviral drug resistance and human immunodeficiency virus type 1 (HIV-1) diversity in Mato Grosso State, central western Brazil are reported. Drug-naïve patients (n = 105) were recruited at a reference center in Cuiabá/Mato Grosso State located across the border with Bolivia and considered a southern gate to the Amazon forest. For 92 HIV-1 isolates, the protease and partial reverse transcriptase fragments were amplified by nested-PCR and sequenced. Drug resistance was analyzed by the Calibrated Population Resistance tool and the International AIDS Society-USA database. HIV-1 subtypes were determined by REGA and phylogenetic analyses. Recombinant viruses were analyzed by SIMPLOT. Drug resistance mutations were observed in 5.4%: nucleoside reverse transcriptase inhibitor mutations M41L (n = 1), D67N (n = 1), and K219E (n = 1), the non-nucleoside reverse transcriptase inhibitor mutation K103N (n = 1) and the protease inhibitor mutation L90M (n = 1). Around 20% of the isolates were recombinants: different patterns of B/F1 mosaics (n = 11), four B/C, one F1/C/B, one F1/C, and one D/F1. Subtype B(PR) B(RT) represented 71.7%, 5.4% were of subtype C(PR) C(RT) and 3.3% were of subtype F1(PR) F1(RT) . A moderate prevalence of transmitted resistance and the co-circulation of subtypes B, F1, C, different recombinants, including the first report of subtype D, were found in Mato Grosso State, far from the epicenter of the epidemic. These results highlight the importance of monitoring transmitted drug resistance and HIV-1 genetic diversity in the interior regions of Brazil.

  19. Decreased incidence of syphilis in both men and women associated with male circumcision: a prospective study among HIV-1 serodiscordant heterosexual African couples

    PubMed Central

    Pintye, Jillian; Baeten, Jared M.; Manhart, Lisa; Celum, Connie; Ronald, Allan; Mugo, Nelly; Mujugira, Andrew; Cohen, Craig; Were, Edwin; Bukusi, Elizabeth; Kiarie, James; Heffron, Renee

    2014-01-01

    Background Male circumcision is a primary HIV-1 prevention intervention for men. It is uncertain whether male circumcision reduces the risk of syphilis among men and their female partners. Methods Using data from a prospective study among HIV-1 serodiscordant heterosexual couples from Kenya and Uganda, we assessed whether male circumcision was associated with incident syphilis in men and in their female partners. Multivariate Andersen-Gill survival methods were used, adjusted for age, sexual behavior, and plasma HIV-1 RNA levels of the HIV-1 infected partner. Findings 4716 HIV-1 serodiscordant couples (37·5% with an HIV-1 infected male) were followed for a median of 2·75 years. At enrollment, 1575 (53·5%) HIV-1 uninfected and 560 (32·4%) HIV-1 infected men were circumcised; an additional 69 (4·2%) HIV-1 infected and 132 (4·8%) HIV-1 uninfected men became circumcised during study follow up. 221 incident syphilis infections were observed: 46 among HIV-1 infected men (incidence 1·10 per 100 person-years), 76 among HIV-1 uninfected men (1·09 per 100 person-years), 54 among HIV-1 infected women (0·77 per 100 person-years) and 45 among HIV-1 uninfected women (1·11 per 100 person-years). Male circumcision was associated with a 42% reduction in incident syphilis in men (adjusted hazard ratio [aHR] 0.58 95% CI 0·37–0·91) including a 62% reduction among HIV-1 infected men (aHR 0·38, 95% CI 0·18–0·81) and a non-significant reduction in incident syphilis among HIV-1 uninfected men (aHR 0·64, 95% CI 0·36–1·11). Among women, circumcision of their male partners was associated with a 59% reduction in incident syphilis (aHR 0.41 95% CI 0.25–0.69), including a 75% reduction among HIV-1 uninfected women (aHR 0·25, 95% CI 0·08–0·76) and a 48% reduction among HIV-1 infected women (aHR 0·52, 95% CI 0·27–0·97). Interpretation In this large prospective cohort study among HIV-1 serodiscordant couples, male circumcision was associated with decreased risk

  20. Association of Age at First Sex with HIV-1, HSV-2 and other Sexual Transmitted Infections among Women in Northern Tanzania

    PubMed Central

    Ghebremichael, Musie; Larsen, Ulla; Paintsil, Elijah

    2012-01-01

    Background To examine the association between age at first sex and the prevalence of sexually transmitted infections (STIs) including, HIV-1, and HSV-2 in women in Moshi urban district, northern Tanzania. Methods A total of 2,019 women aged 20–44 were randomly selected in a two-stage sampling from Moshi urban district, northern Tanzania. Information on demographics and sexual behaviors were obtained. Blood and urine samples were drawn for testing of HIV-1, HSV-2 and other STIs. Results Women who had their first sexual intercourse at age 18–19 (OR=0.66; 95% CI=0.50–0.86) or 20+ (OR=0.46; 95% CI=0.36–0.60) were less likely to have STIs, including HIV-1 and HSV-2, than women who had their first intercourse before their 18th birthday. The hazards of having had first sex at an earlier age were significantly higher for women who tested positive for STIs (HR=1.52; 95% CI: 1.37–1.69) or had STI symptoms (HR=1.17; 95% CI: 1.05–1.30). Early age at first sex was associated with having a regular non-cohabiting partner (HR=1.40; 95% CI: 1.23–1.58), female circumcision (HR=1.20; 95% CI: 1.02–1.40), and coercion at first intercourse (HR=1.47; 95% CI: 1.15–1.89). Conclusions In sub-Saharan Africa, where the prevalence of HIV and other STIs is high, a better understanding of the determinants of the age at first sex is crucial for HIV/STI prevention programs. Prevention programs should not only aim at delaying the age at first sex but also address factors leading to early age at first sex. PMID:19707109

  1. Transmitted Drug Resistance and Antiretroviral Treatment Outcomes in Non-Subtype B HIV1- Infected Patients in South East Asia

    PubMed Central

    Phanuphak, Praphan; Sirivichayakul, Sunee; Jiamsakul, Awachana; Sungkanuparph, Somnuek; Kumarasamy, Nagalingeswaran; Lee, Man Po; Sirisanthana, Thira; Kantipong, Pacharee; Lee, Christopher; Kamarulzaman, Adeeba; Mustafa, Mahiran; Ditangco, Rossana; Merati, Tuti; Ratanasuwan, Winai; Singtoroj, Thida; Kantor, Rami

    2014-01-01

    Background We compared treatment outcomes of transmitted drug resistance (TDR) in patients on fully or partially sensitive drug regimens. Methods Factors associated with survival and failure were analyzed using Cox proportional hazards and discrete time conditional logistic models. Results TDR, found in 60/1471 (4.1%) Asian treatment naïve patients, was one of the significant predictors of failure. Patients with TDR to >1 drug in their regimen were >3 times as likely to fail compared to no TDR. Conclusion TDR was associated with failure in the context of non-fully sensitive regimens. Efforts are needed to incorporate resistance testing into national treatment programs. PMID:24413039

  2. Treatment of primary HIV-1 infection with cyclosporin A coupled with highly active antiretroviral therapy

    PubMed Central

    Rizzardi, G. Paolo; Harari, Alexandre; Capiluppi, Brunella; Tambussi, Giuseppe; Ellefsen, Kim; Ciuffreda, Donatella; Champagne, Patrick; Bart, Pierre-Alexandre; Chave, Jean-Philippe; Lazzarin, Adriano; Pantaleo, Giuseppe

    2002-01-01

    Primary HIV-1 infection causes extensive immune activation, during which CD4+ T cell activation supports massive HIV-1 production. We tested the safety and the immune-modulating effects of combining cyclosporin A (CsA) treatment with highly active antiretroviral therapy (HAART) during primary HIV-1 infection. Nine adults with primary HIV-1 infection were treated with CsA along with HAART. At week 8, all patients discontinued CsA but maintained HAART. Viral replication was suppressed to a comparable extent in the CsA + HAART cohort and in 29 control patients whose primary infection was treated with HAART alone. CsA restored normal CD4+ T cell levels, both in terms of percentage and absolute numbers. The increase in CD4+ T cells was apparent within a week and persisted throughout the study period. CsA was not detrimental to virus-specific CD8+ or CD4+ T cell responses. At week 48, the proportion of IFN-γ–secreting CD4+ and CD4+CCR7– T cells was significantly higher in the CsA + HAART cohort than in the HAART-alone cohort. In conclusion, rapid shutdown of T cell activation in the early phases of primary HIV-1 infection can have long-term beneficial effects and establish a more favorable immunologic set-point. Appropriate, immune-based therapeutic interventions may represent a valuable complement to HAART for treating HIV infection. PMID:11877476

  3. HIV-1 capsid undergoes coupled binding and isomerization by the nuclear pore protein NUP358

    PubMed Central

    2013-01-01

    Background Lentiviruses such as HIV-1 can be distinguished from other retroviruses by the cyclophilin A-binding loop in their capsid and their ability to infect non-dividing cells. Infection of non-dividing cells requires transport through the nuclear pore but how this is mediated is unknown. Results Here we present the crystal structure of the N-terminal capsid domain of HIV-1 in complex with the cyclophilin domain of nuclear pore protein NUP358. The structure reveals that HIV-1 is positioned to allow single-bond resonance stabilisation of exposed capsid residue P90. NMR exchange experiments demonstrate that NUP358 is an active isomerase, which efficiently catalyzes cis-trans isomerization of the HIV-1 capsid. In contrast, the distantly related feline lentivirus FIV can bind NUP358 but is neither isomerized by it nor requires it for infection. Conclusion Isomerization by NUP358 may be preserved by HIV-1 to target the nuclear pore and synchronize nuclear entry with capsid uncoating. PMID:23902822

  4. Trends and Predictors of Transmitted Drug Resistance (TDR) and Clusters with TDR in a Local Belgian HIV-1 Epidemic

    PubMed Central

    Pineda-Peña, Andrea-Clemencia; Schrooten, Yoeri; Vinken, Lore; Ferreira, Fossie; Li, Guangdi; Trovão, Nídia Sequeira; Khouri, Ricardo; Derdelinckx, Inge; De Munter, Paul; Kücherer, Claudia; Kostrikis, Leondios G.; Nielsen, Claus; Littsola, Kirsi; Wensing, Annemarie; Stanojevic, Maja; Paredes, Roger; Balotta, Claudia; Albert, Jan; Boucher, Charles; Gomez-Lopez, Arley; Van Wijngaerden, Eric; Van Ranst, Marc; Vercauteren, Jurgen; Vandamme, Anne-Mieke; Van Laethem, Kristel

    2014-01-01

    We aimed to study epidemic trends and predictors for transmitted drug resistance (TDR) in our region, its clinical impact and its association with transmission clusters. We included 778 patients from the AIDS Reference Center in Leuven (Belgium) diagnosed from 1998 to 2012. Resistance testing was performed using population-based sequencing and TDR was estimated using the WHO-2009 surveillance list. Phylogenetic analysis was performed using maximum likelihood and Bayesian techniques. The cohort was predominantly Belgian (58.4%), men who have sex with men (MSM) (42.8%), and chronically infected (86.5%). The overall TDR prevalence was 9.6% (95% confidence interval (CI): 7.7–11.9), 6.5% (CI: 5.0–8.5) for nucleoside reverse transcriptase inhibitors (NRTI), 2.2% (CI: 1.4–3.5) for non-NRTI (NNRTI), and 2.2% (CI: 1.4–3.5) for protease inhibitors. A significant parabolic trend of NNRTI-TDR was found (p = 0.019). Factors significantly associated with TDR in univariate analysis were male gender, Belgian origin, MSM, recent infection, transmission clusters and subtype B, while multivariate and Bayesian network analysis singled out subtype B as the most predictive factor of TDR. Subtype B was related with transmission clusters with TDR that included 42.6% of the TDR patients. Thanks to resistance testing, 83% of the patients with TDR who started therapy had undetectable viral load whereas half of the patients would likely have received a suboptimal therapy without this test. In conclusion, TDR remained stable and a NNRTI up-and-down trend was observed. While the presence of clusters with TDR is worrying, we could not identify an independent, non-sequence based predictor for TDR or transmission clusters with TDR that could help with guidelines or public health measures. PMID:25003369

  5. Integrated Delivery of Antiretroviral Treatment and Pre-exposure Prophylaxis to HIV-1–Serodiscordant Couples: A Prospective Implementation Study in Kenya and Uganda

    PubMed Central

    Baeten, Jared M.; Heffron, Renee; Kidoguchi, Lara; Mugo, Nelly R.; Katabira, Elly; Bukusi, Elizabeth A.; Asiimwe, Stephen; Haberer, Jessica E.; Ngure, Kenneth; Bulya, Nulu; Odoyo, Josephine; Hendrix, Craig; Marzinke, Mark A.; Ware, Norma C.; Wyatt, Monique A.; Morrison, Susan; Mujugira, Andrew; Donnell, Deborah; Celum, Connie

    2016-01-01

    Background Antiretroviral-based interventions for HIV-1 prevention, including antiretroviral therapy (ART) to reduce the infectiousness of HIV-1 infected persons and pre-exposure prophylaxis (PrEP) to reduce the susceptibility of HIV-1 uninfected persons, showed high efficacy for HIV-1 protection in randomized clinical trials. We conducted a prospective implementation study to understand the feasibility and effectiveness of these interventions in delivery settings. Methods and Findings Between November 5, 2012, and January 5, 2015, we enrolled and followed 1,013 heterosexual HIV-1-serodiscordant couples in Kenya and Uganda in a prospective implementation study. ART and PrEP were offered through a pragmatic strategy, with ART promoted for all couples and PrEP offered until 6 mo after ART initiation by the HIV-1 infected partner, permitting time to achieve virologic suppression. One thousand thirteen couples were enrolled, 78% of partnerships initiated ART, and 97% used PrEP, during a median follow-up of 0.9 years. Objective measures of adherence to both prevention strategies demonstrated high use (≥85%). Given the low HIV-1 incidence observed in the study, an additional analysis was added to compare observed incidence to incidence estimated under a simulated counterfactual model constructed using data from a prior prospective study of HIV-1-serodiscordant couples. Counterfactual simulations predicted 39.7 HIV-1 infections would be expected in the population at an incidence of 5.2 per 100 person-years (95% CI 3.7–6.9). However, only two incident HIV-1 infections were observed, at an incidence of 0.2 per 100 person-years (95% CI 0.0–0.9, p < 0.0001 versus predicted). The use of a non-concurrent comparison of HIV-1 incidence is a potential limitation of this approach; however, it would not have been ethical to enroll a contemporaneous population not provided access to ART and PrEP. Conclusions Integrated delivery of time-limited PrEP until sustained ART use in

  6. Epidemiological Surveillance of HIV-1 Transmitted Drug Resistance in Spain in 2004-2012: Relevance of Transmission Clusters in the Propagation of Resistance Mutations

    PubMed Central

    Vega, Yolanda; Delgado, Elena; Fernández-García, Aurora; Cuevas, Maria Teresa; Thomson, Michael M.; Montero, Vanessa; Sánchez, Monica; Sánchez, Ana Maria; Pérez-Álvarez, Lucia

    2015-01-01

    Our objectives were to carry out an epidemiological surveillance study on transmitted drug resistance (TDR) among individuals newly diagnosed of HIV-1 infection during a nine year period in Spain and to assess the role of transmission clusters (TC) in the propagation of resistant strains. An overall of 1614 newly diagnosed individuals were included in the study from January 2004 through December 2012. Individuals come from two different Spanish regions: Galicia and the Basque Country. Resistance mutations to reverse transcriptase inhibitors (RTI) and protease inhibitors (PI) were analyzed according to mutations included in the surveillance drug-resistance mutations list updated in 2009. TC were defined as those comprising viruses from five or more individuals whose sequences clustered in maximum likelihood phylogenetic trees with a bootstrap value ≥90%. The overall prevalence of TDR to any drug was 9.9%: 4.9% to nucleoside RTIs (NRTIs), 3.6% to non-nucleoside RTIs (NNRTIs), and 2.7% to PIs. A significant decrease of TDR to NRTIs over time was observed [from 10% in 2004 to 2% in 2012 (p=0.01)]. Sixty eight (42.2%) of 161 sequences with TDR were included in 25 TC composed of 5 or more individuals. Of them, 9 clusters harbored TDR associated with high level resistance to antiretroviral drugs. T215D revertant mutation was transmitted in a large cluster comprising 25 individuals. The impact of epidemiological networks on TDR frequency may explain its persistence in newly diagnosed individuals. The knowledge of the populations involved in TC would facilitate the design of prevention programs and public health interventions. PMID:26010948

  7. Geographic and Temporal Trends in the Molecular Epidemiology and Genetic Mechanisms of Transmitted HIV-1 Drug Resistance: An Individual-Patient- and Sequence-Level Meta-Analysis

    PubMed Central

    Rhee, Soo-Yon; Blanco, Jose Luis; Jordan, Michael R.; Taylor, Jonathan; Lemey, Philippe; Varghese, Vici; Hamers, Raph L.; Bertagnolio, Silvia; de Wit, Tobias F. Rinke; Aghokeng, Avelin F.; Albert, Jan; Avi, Radko; Avila-Rios, Santiago; Bessong, Pascal O.; Brooks, James I.; Boucher, Charles A. B.; Brumme, Zabrina L.; Busch, Michael P.; Bussmann, Hermann; Chaix, Marie-Laure; Chin, Bum Sik; D’Aquin, Toni T.; De Gascun, Cillian F.; Derache, Anne; Descamps, Diane; Deshpande, Alaka K.; Djoko, Cyrille F.; Eshleman, Susan H.; Fleury, Herve; Frange, Pierre; Fujisaki, Seiichiro; Harrigan, P. Richard; Hattori, Junko; Holguin, Africa; Hunt, Gillian M.; Ichimura, Hiroshi; Kaleebu, Pontiano; Katzenstein, David; Kiertiburanakul, Sasisopin; Kim, Jerome H.; Kim, Sung Soon; Li, Yanpeng; Lutsar, Irja; Morris, Lynn; Ndembi, Nicaise; NG, Kee Peng; Paranjape, Ramesh S.; Peeters, Martine; Poljak, Mario; Price, Matt A.; Ragonnet-Cronin, Manon L.; Reyes-Terán, Gustavo; Rolland, Morgane; Sirivichayakul, Sunee; Smith, Davey M.; Soares, Marcelo A.; Soriano, Vincent V.; Ssemwanga, Deogratius; Stanojevic, Maja; Stefani, Mariane A.; Sugiura, Wataru; Sungkanuparph, Somnuek; Tanuri, Amilcar; Tee, Kok Keng; Truong, Hong-Ha M.; van de Vijver, David A. M. C.; Vidal, Nicole; Yang, Chunfu; Yang, Rongge; Yebra, Gonzalo; Ioannidis, John P. A.; Vandamme, Anne-Mieke; Shafer, Robert W.

    2015-01-01

    Background Regional and subtype-specific mutational patterns of HIV-1 transmitted drug resistance (TDR) are essential for informing first-line antiretroviral (ARV) therapy guidelines and designing diagnostic assays for use in regions where standard genotypic resistance testing is not affordable. We sought to understand the molecular epidemiology of TDR and to identify the HIV-1 drug-resistance mutations responsible for TDR in different regions and virus subtypes. Methods and Findings We reviewed all GenBank submissions of HIV-1 reverse transcriptase sequences with or without protease and identified 287 studies published between March 1, 2000, and December 31, 2013, with more than 25 recently or chronically infected ARV-naïve individuals. These studies comprised 50,870 individuals from 111 countries. Each set of study sequences was analyzed for phylogenetic clustering and the presence of 93 surveillance drug-resistance mutations (SDRMs). The median overall TDR prevalence in sub-Saharan Africa (SSA), south/southeast Asia (SSEA), upper-income Asian countries, Latin America/Caribbean, Europe, and North America was 2.8%, 2.9%, 5.6%, 7.6%, 9.4%, and 11.5%, respectively. In SSA, there was a yearly 1.09-fold (95% CI: 1.05–1.14) increase in odds of TDR since national ARV scale-up attributable to an increase in non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance. The odds of NNRTI-associated TDR also increased in Latin America/Caribbean (odds ratio [OR] = 1.16; 95% CI: 1.06–1.25), North America (OR = 1.19; 95% CI: 1.12–1.26), Europe (OR = 1.07; 95% CI: 1.01–1.13), and upper-income Asian countries (OR = 1.33; 95% CI: 1.12–1.55). In SSEA, there was no significant change in the odds of TDR since national ARV scale-up (OR = 0.97; 95% CI: 0.92–1.02). An analysis limited to sequences with mixtures at less than 0.5% of their nucleotide positions—a proxy for recent infection—yielded trends comparable to those obtained using the complete dataset. Four

  8. Transformer coupling for transmitting direct current through a barrier

    DOEpatents

    Brown, R.L.; Guilford, R.P.; Stichman, J.H.

    1987-06-29

    The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level. 4 figs.

  9. Transformer coupling for transmitting direct current through a barrier

    DOEpatents

    Brown, Ralph L.; Guilford, Richard P.; Stichman, John H.

    1988-01-01

    The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level.

  10. Surveys of HIV-1, HTLV-I, and other sexually transmitted diseases in female sex workers in Taipei City, Taiwan, from 1993 to 1996.

    PubMed

    Chen, Y M; Yu, P S; Lin, C C; Jen, I

    1998-07-01

    Between 1993 and 1996 in Taipei, Taiwan, we studied the prevalences of HIV-1, HTLV-I, HSV-2, Chlamydia trachomatis, and syphilis infection in female commercial sex workers (CSW) and the pathogens' associated risk factors. Female CSW from nine massage parlors, two karaoke bars (KB), and 22 brothels in Taipei city participated in this study. Two of 557 (0.4%) KB CSWs from those who participated during the period from 1993 to 1994 had HIV-1 infection, whereas no KB CSWs in the periods 1994 to 1995 or 1995 to 1996 had HIV-1 infection. None of the 725 MP CSWs or 291 brothel CSWs who participated in the study between 1993 and 1996 had HIV-1 infection. In contrast, CSWs from brothels had elevated rates of both HTLV-I and active chlamydia infections compared with KB and MP CSWs (p < .05 and p < .005, respectively). KB CSWs showed an elevated rate of HSV-2 infection in the years 1993 and 1994 when compared with CSWs employed by brothels and MPs (p < .005). The prevalence rates of syphilis for CSWs from brothels dropped from 42.8% in the year 1993 to 1994 to 26.3% in the 1995 to 1996 period, whereas for KB and MP CSWs, the rates were < 6% in each of year studied.

  11. Kinetically coupled folding of a single HIV-1 glycoprotein 41 complex in viral membrane fusion and inhibition

    PubMed Central

    Jiao, Junyi; Rebane, Aleksander A.; Ma, Lu; Gao, Ying; Zhang, Yongli

    2015-01-01

    HIV-1 glycoprotein 41 (gp41) mediates viral entry into host cells by coupling its folding energy to membrane fusion. Gp41 folding is blocked by fusion inhibitors, including the commercial drug T20, to treat HIV/AIDS. However, gp41 folding intermediates, energy, and kinetics are poorly understood. Here, we identified the folding intermediates of a single gp41 trimer-of-hairpins and measured their associated energy and kinetics using high-resolution optical tweezers. We found that folding of gp41 hairpins was energetically independent but kinetically coupled: Each hairpin contributed a folding energy of ∼−23 kBT, but folding of one hairpin successively accelerated the folding rate of the next one by ∼20-fold. Membrane-mimicking micelles slowed down gp41 folding and reduced the stability of the six-helix bundle. However, the stability was restored by cooperative folding of the membrane-proximal external region. Surprisingly, T20 strongly inhibited gp41 folding by actively displacing the C-terminal hairpin strand in a force-dependent manner. The inhibition was abolished by a T20-resistant gp41 mutation. The energetics and kinetics of gp41 folding established by us provides a basis to understand viral membrane fusion, infection, and therapeutic intervention. PMID:26038562

  12. Antiviral factors and type I/III interferon expression associated with regulatory factors in the oral epithelial cells from HIV-1-serodiscordant couples

    PubMed Central

    Cervantes, Cesar A. C.; Oliveira, Luanda M. S.; Manfrere, Kelly C. G.; Lima, Josenilson F.; Pereira, Natalli Z.; Duarte, Alberto J. S.; Sato, Maria N.

    2016-01-01

    Individuals who remain HIV-seronegative despite repeated unprotected exposure to the virus are defined as exposed seronegative (ESN) individuals. Innate and adaptive immunity, as well as genetic factors, provide ESNs with important advantages that allow for low infection susceptibility. The majority of HIV-1-infected individuals undergo antiretroviral therapy, which can decrease the level of HIV-1 exposure in ESNs. We analyzed type I interferon (IFN)-related antiviral and regulatory factors in peripheral blood mononuclear cells (PBMCs) and oral epithelial cells from serodiscordant couples. Our findings revealed that ESNs did not induce the expression of antiviral factors (APOBEC-3G, TRIM5-α, SAMDH1, STING, TBk1) or regulatory factors (Trex, Foxo3, Socs3, IL-10) in PBMCs, unlike their HIV-1-infected partners. In contrast, ESNs upregulated APOBEC-3G and type I/III IFNs (IFNs-α,-β/-λ) in oral mucosal epithelial cells similar to their HIV-infected partners. The serodiscordant groups exhibited an increased expression of type I IFN-induced regulators, such as Trex and Foxo3, in oral epithelial cells. TLR7, TLR8 and TLR9 were expressed in oral epithelial cells of both ESNs and HIV-1-infected subjects. These findings revealed evidence of antiviral factors, type I/III interferon and regulatory factor expression only in the oral mucosal compartment of ESNs, while HIV-1-infected partners systemically and oral mucosal expressed the antiviral profile. PMID:27168019

  13. Molecular diversity of HIV-1 and surveillance of transmitted drug resistance variants among treatment Naïve patients, 5 years after active introduction of HAART in Kuala Lumpur, Malaysia.

    PubMed

    Ong, Lai Yee; Razak, Siti Nur Humaira; Lee, Yeat Mei; Sri La Sri Ponnampalavanar, Sasheela; Syed Omar, Sharifah Faridah; Azwa, Raja Iskandar; Tee, Kok Keng; Kamarulzaman, Adeeba

    2014-01-01

    Expansion of antiretroviral treatment programs have led to the growing concern for the development of antiretroviral drug resistance. The aims were to assess the prevalence of drug resistant HIV-1 variants and to identify circulating subtypes among HAART-naïve patients. Plasma specimens from N = 100 HIV+ HAART-naïve adult were collected between March 2008 and August 2010 and viral RNA were extracted for nested PCR and sequenced. PR-RT sequences were protein aligned and checked for transmitted drug resistance mutations. Phylogenetic reconstruction and recombination analysis were performed to determine the genotypes. Based on the WHO consensus guidelines, none of the recruited patients had any transmitted drug resistance mutations. When analyzed against the Stanford guidelines, 35% of patients had at least one reported mutation that may reduce drug susceptibility to PI (24%), NRTI (5%), and NNRTI (14%). The commonly detected mutation that may affect current first line therapy was V179D (3%), which may lead to reduced susceptibility to NNRTI. The predominant circulating HIV-1 genotypes were CRF01_AE (51%) and CRF33_01B (17%). The prevalence of unique recombinant forms (URF) was 7%; five distinct recombinant structures involving CRF01_AE and subtype B' were observed, among them a cluster of three isolates that could form a novel circulating recombinant form (CRF) candidate. Transmitted drug resistance prevalence among HAART-naïve patients was low in this cohort of patients in Kuala Lumpur despite introduction of HAART 5 years ago. Owing to the high genetic diversity, continued molecular surveillance can identify the persistent emergence of HIV-1 URF and novel CRF with significant epidemiological impact.

  14. Transmitted/Founder and Chronic Subtype C HIV-1 Use CD4 and CCR5 Receptors with Equal Efficiency and Are Not Inhibited by Blocking the Integrin α4β7

    PubMed Central

    Banks, Lauren B.; Iyer, Shilpa S.; Pfaff, Jennifer M.; Salazar-Gonzalez, Jesus F.; Salazar, Maria G.; Decker, Julie M.; Parrish, Erica H.; Berg, Anna; Hopper, Jennifer; Hora, Bhavna; Kumar, Amit; Mahlokozera, Tatenda; Yuan, Sally; Coleman, Charl; Vermeulen, Marion; Ding, Haitao; Ochsenbauer, Christina; Tilton, John C.; Permar, Sallie R.; Kappes, John C.; Betts, Michael R.; Busch, Michael P.; Gao, Feng; Montefiori, David; Haynes, Barton F.; Shaw, George M.; Hahn, Beatrice H.; Doms, Robert W.

    2012-01-01

    Sexual transmission of human immunodeficiency virus type 1 (HIV-1) most often results from productive infection by a single transmitted/founder (T/F) virus, indicating a stringent mucosal bottleneck. Understanding the viral traits that overcome this bottleneck could have important implications for HIV-1 vaccine design and other prevention strategies. Most T/F viruses use CCR5 to infect target cells and some encode envelope glycoproteins (Envs) that contain fewer potential N-linked glycosylation sites and shorter V1/V2 variable loops than Envs from chronic viruses. Moreover, it has been reported that the gp120 subunits of certain transmitted Envs bind to the gut-homing integrin α4β7, possibly enhancing virus entry and cell-to-cell spread. Here we sought to determine whether subtype C T/F viruses, which are responsible for the majority of new HIV-1 infections worldwide, share biological properties that increase their transmission fitness, including preferential α4β7 engagement. Using single genome amplification, we generated panels of both T/F (n = 20) and chronic (n = 20) Env constructs as well as full-length T/F (n = 6) and chronic (n = 4) infectious molecular clones (IMCs). We found that T/F and chronic control Envs were indistinguishable in the efficiency with which they used CD4 and CCR5. Both groups of Envs also exhibited the same CD4+ T cell subset tropism and showed similar sensitivity to neutralization by CD4 binding site (CD4bs) antibodies. Finally, saturating concentrations of anti-α4β7 antibodies failed to inhibit infection and replication of T/F as well as chronic control viruses, although the growth of the tissue culture-adapted strain SF162 was modestly impaired. These results indicate that the population bottleneck associated with mucosal HIV-1 acquisition is not due to the selection of T/F viruses that use α4β7, CD4 or CCR5 more efficiently. PMID:22693444

  15. High frequency of transmitted HIV-1 Gag HLA class I-driven immune escape variants but minimal immune selection over the first year of clade C infection.

    PubMed

    Gounder, Kamini; Padayachi, Nagavelli; Mann, Jaclyn K; Radebe, Mopo; Mokgoro, Mammekwa; van der Stok, Mary; Mkhize, Lungile; Mncube, Zenele; Jaggernath, Manjeetha; Reddy, Tarylee; Walker, Bruce D; Ndung'u, Thumbi

    2015-01-01

    In chronic HIV infection, CD8+ T cell responses to Gag are associated with lower viral loads, but longitudinal studies of HLA-restricted CD8+ T cell-driven selection pressure in Gag from the time of acute infection are limited. In this study we examined Gag sequence evolution over the first year of infection in 22 patients identified prior to seroconversion. A total of 310 and 337 full-length Gag sequences from the earliest available samples (median = 14 days after infection [Fiebig stage I/II]) and at one-year post infection respectively were generated. Six of 22 (27%) individuals were infected with multiple variants. There was a trend towards early intra-patient viral sequence diversity correlating with viral load set point (p = 0.07, r = 0.39). At 14 days post infection, 59.7% of Gag CTL epitopes contained non-consensus polymorphisms and over half of these (35.3%) comprised of previously described CTL escape variants. Consensus and variant CTL epitope proportions were equally distributed irrespective of the selecting host HLA allele and most epitopes remained unchanged over 12 months post infection. These data suggest that intrapatient diversity during acute infection is an indicator of disease outcome. In this setting, there is a high rate of transmitted CTL escape variants and limited immune selection in Gag during the first year of infection. These data have relevance for vaccine strategies designed to elicit effective CD8+ T cell immune responses. PMID:25781986

  16. High Frequency of Transmitted HIV-1 Gag HLA Class I-Driven Immune Escape Variants but Minimal Immune Selection over the First Year of Clade C Infection

    PubMed Central

    Gounder, Kamini; Padayachi, Nagavelli; Mann, Jaclyn K.; Radebe, Mopo; Mokgoro, Mammekwa; van der Stok, Mary; Mkhize, Lungile; Mncube, Zenele; Jaggernath, Manjeetha; Reddy, Tarylee; Walker, Bruce D.; Ndung’u, Thumbi

    2015-01-01

    In chronic HIV infection, CD8+ T cell responses to Gag are associated with lower viral loads, but longitudinal studies of HLA-restricted CD8+ T cell-driven selection pressure in Gag from the time of acute infection are limited. In this study we examined Gag sequence evolution over the first year of infection in 22 patients identified prior to seroconversion. A total of 310 and 337 full-length Gag sequences from the earliest available samples (median = 14 days after infection [Fiebig stage I/II]) and at one-year post infection respectively were generated. Six of 22 (27%) individuals were infected with multiple variants. There was a trend towards early intra-patient viral sequence diversity correlating with viral load set point (p = 0.07, r = 0.39). At 14 days post infection, 59.7% of Gag CTL epitopes contained non-consensus polymorphisms and over half of these (35.3%) comprised of previously described CTL escape variants. Consensus and variant CTL epitope proportions were equally distributed irrespective of the selecting host HLA allele and most epitopes remained unchanged over 12 months post infection. These data suggest that intrapatient diversity during acute infection is an indicator of disease outcome. In this setting, there is a high rate of transmitted CTL escape variants and limited immune selection in Gag during the first year of infection. These data have relevance for vaccine strategies designed to elicit effective CD8+ T cell immune responses. PMID:25781986

  17. Passively transmitted gp41 antibodies in babies born from HIV-1 subtype C-seropositive women: correlation between fine specificity and protection.

    PubMed

    Diomede, L; Nyoka, S; Pastori, C; Scotti, L; Zambon, A; Sherman, G; Gray, C M; Sarzotti-Kelsoe, M; Lopalco, L

    2012-04-01

    HIV-exposed, uninfected (EUN) babies born to HIV-infected mothers are examples of natural resistance to HIV infection. In this study, we evaluated the titer and neutralizing potential of gp41-specific maternal antibodies and their correlation with HIV transmission in HIV-infected mother-child pairs. Specific gp41-binding and -neutralizing antibodies were determined in a cohort of 74 first-time mother-child pairs, of whom 40 mothers were infected with HIV subtype C. Within the infected mother cohort, 16 babies were born infected and 24 were PCR negative and uninfected at birth (i.e., exposed but uninfected). Thirty-four HIV-uninfected and HIV-unexposed mother-child pairs were included as controls. All HIV-positive mothers and their newborns showed high IgG titers to linear epitopes within the HR1 region and to the membrane-proximal (MPER) domain of gp41; most sera also recognized the disulfide loop immunodominant epitope (IDE). Antibody titers to the gp41 epitopes were significantly lower in nontransmitting mothers (P < 0.01) and in the EUN babies (P < 0.005) than in HIV-positive mother-child pairs. Three domains of gp41, HR1, IDE, and MPER, elicited antibodies that were effectively transmitted to EUN babies. Moreover, in EUN babies, epitopes overlapping the 2F5 epitope (ELDKWAS), but not the 4E10 epitope, were neutralization targets in two out of four viruses tested. Our findings highlight important epitopes in gp41 that appear to be associated with exposure without infection and would be important to consider for vaccine design.

  18. Key-and-keyway coupling for transmitting torque

    DOEpatents

    Blue, S.C.; Curtis, M.T.; Orthwein, W.C.; Stitt, D.H.

    1975-11-18

    The design of an improved key-and-keyway coupling for the transmission of torque is given. The coupling provides significant reductions in stress concentrations in the vicinity of the key and keyway. The keyway is designed with a flat-bottomed u-shaped portion whose inboard end terminates in a ramp which is dished transversely, so that the surface of the ramp as viewed in transverse section defines an outwardly concave arc.

  19. An Agile Beam Transmit Array Using Coupled Oscillator Phase Control

    NASA Technical Reports Server (NTRS)

    Pogorzelski, Ronald S.; Scaramastra, Rocco P.; Huang, John; Beckon, Robert J.; Petree, Steve M.; Chavez, Cosme

    1993-01-01

    A few years ago York and colleagues suggested that injection locking of voltage controlled oscillators could be used to implement beam steering in a phased array [I]. The scheme makes use of the fact that when an oscillator is injection locked to an external signal, the phase difference between the output of the oscillator and the injection signal is governed by the difference between the injection frequency and the free running frequency of the oscillator (the frequency to which the oscillator is tuned). Thus, if voltage controlled oscillators (VCOs) are used, this phase difference is controlled by an applied voltage. Now, if a set of such oscillators are coupled to nearest neighbors, they can be made to mutually injection lock and oscillate as an ensemble. If they are all tuned to the same frequency, they will all oscillate in phase. Thus, if the outputs are connected to radiating elements forming a linear array, the antenna will radiate normal to the line of elements. Scanning is accomplished by antisymmetrically detuning the end oscillators in the array by application of a pair of appropriate voltages to their tuning ports. This results in a linear phase progression across the array which is just the phasing required to scan the beam. The scan angle is determined by the degree of detuning. We have constructed a seven element one dimensional agile beam array at S-band based on the above principle. Although, a few such arrays have been built in the past, this array possesses two unique features. First, the VCO MMICs have buffer amplifiers which isolate the output from the tuning circuit, and second, the oscillators are weakly coupled to each other at their resonant circuits rather than their outputs. This results in a convenient isolation between the oscillator array design and the radiating aperture design. An important parameter in the design is the so called coupling phase which determines the phase shift of the signals passing from one oscillator to its

  20. Analytical Model and Optimized Design of Power Transmitting Coil for Inductively Coupled Endoscope Robot.

    PubMed

    Ke, Quan; Luo, Weijie; Yan, Guozheng; Yang, Kai

    2016-04-01

    A wireless power transfer system based on the weakly inductive coupling makes it possible to provide the endoscope microrobot (EMR) with infinite power. To facilitate the patients' inspection with the EMR system, the diameter of the transmitting coil is enlarged to 69 cm. Due to the large transmitting range, a high quality factor of the Litz-wire transmitting coil is a necessity to ensure the intensity of magnetic field generated efficiently. Thus, this paper builds an analytical model of the transmitting coil, and then, optimizes the parameters of the coil by enlarging the quality factor. The lumped model of the transmitting coil includes three parameters: ac resistance, self-inductance, and stray capacitance. Based on the exact two-dimension solution, the accurate analytical expression of ac resistance is derived. Several transmitting coils of different specifications are utilized to verify this analytical expression, being in good agreements with the measured results except the coils with a large number of strands. Then, the quality factor of transmitting coils can be well predicted with the available analytical expressions of self- inductance and stray capacitance. Owing to the exact estimation of quality factor, the appropriate coil turns of the transmitting coil is set to 18-40 within the restrictions of transmitting circuit and human tissue issues. To supply enough energy for the next generation of the EMR equipped with a Ø9.5×10.1 mm receiving coil, the coil turns of the transmitting coil is optimally set to 28, which can transfer a maximum power of 750 mW with the remarkable delivering efficiency of 3.55%. PMID:26292335

  1. Psychoneuroimmunology and HIV-1.

    ERIC Educational Resources Information Center

    Antoni, Michael H.; And Others

    1990-01-01

    Presents evidence describing benefits of behavioral interventions such as aerobic exercise training on both psychological and immunological functioning among high risk human immunodeficiency virus-Type 1 (HIV-1) seronegative and very early stage seropositive homosexual men. HIV-1 infection is cast as chronic disease for which early…

  2. Sterol Regulatory Element-Binding Protein 2 Couples HIV-1 Transcription to Cholesterol Homeostasis and T Cell Activation ▿§

    PubMed Central

    Taylor, Harry E.; Linde, Michael E.; Khatua, Atanu K.; Popik, Waldemar; Hildreth, James E. K.

    2011-01-01

    Cholesterol plays an essential role in the life cycle of several enveloped viruses. Many of these viruses manipulate host cholesterol metabolism to facilitate their replication. HIV-1 infection of CD4+ T cells activates the sterol regulatory element-binding protein 2 (SREBP2) transcriptional program, which includes genes involved in cholesterol homeostasis. However, the role of SREBP2-dependent transcription in HIV-1 biology has not been fully examined. Here, we identify TFII-I, a gene critical for HIV-1 transcription in activated T cells, as a novel SREBP2 target gene. We found TFII-I expression increased after HIV-1 infection or activation of human primary CD4+ T cells. We show that inhibition of SREBP2 activity reduced TFII-I induction in response to these stimuli. More importantly, small interfering RNA (siRNA)-mediated gene silencing of either SREBP2 or TFII-I significantly reduced HIV-1 production in CD4+ T cells. We also found that TFII-I potentiates Tat-dependent viral gene expression, consistent with a role at the level of HIV-1 transcription. Collectively, our results demonstrate for the first time that HIV-1 transcription in T cells is linked to cholesterol homeostasis through control of TFII-I expression by SREBP2. PMID:21613400

  3. Effect of the HIV-1 fusion peptide on the mechanical properties and leaflet coupling of lipid bilayers

    NASA Astrophysics Data System (ADS)

    Shchelokovskyy, P.; Tristram-Nagle, S.; Dimova, R.

    2011-02-01

    The fusion peptide (FP) of the human immunodeficiency virus (HIV) is part of the N-terminus of the viral envelope glycoprotein gp41 and is believed to play an important role in the viral entry process. To understand the immediate effect of this peptide on the cell membrane, we have studied the influence of the synthetic FP sequence FP23 on the mechanical properties of model lipid bilayers. For this purpose, giant unilamellar vesicles were prepared from the unsaturated lipid dioleoylphosphatidylcholine mixed in various molar ratios with FP23. The bending stiffness of the vesicles was measured with two different methods: fluctuation analysis and aspiration with micropipettes. The data obtained from both of these approaches show that the bending stiffness of the membrane decreases gradually with increasing concentration of the FP23 in the bilayer. Low concentrations of only a few mol% FP23 are sufficient to decrease the bending stiffness of the lipid bilayer by about a factor of 2. Finally, data obtained for the stretching elasticity modulus of the membrane suggest that the peptide insertion decreases the coupling between the two leaflets of the bilayer.

  4. HIV-1 infection may be on the rise in Peru.

    PubMed

    The results of a national survey have indicated that "... HIV-1 infection is epidemic in Peru among groups at high risk of sexually and parenterally transmitted diseases," a multicenter group reported (AIDS 1996; 10: 1141-1145). Although the risk of infection appears to be very low in the general population, it may possibly be increasing, according to Dr. Michael C. McCarthy, US National Naval Medical Center in Bethesda, Maryland. McCarthy's group evaluated over 140,000 serum samples for antibodies to HIV-1 between January 1986 and December 1990 in Peru. HIV-1 antibody was detected in 26% of samples from homosexual men, 10% of samples from male sexually transmitted disease patients, and 13% of samples from drug users. 10% of the samples from hemophiliacs and unlicensed female prostitutes were positive for antibodies to HIV-1. In general, he concluded that the patterns of the HIV-1 epidemic in Peru are similar to those seen in Brazil and "... are also similar to initial transmission patterns of HIV-1 infection of North America." However, McCarthy also noted a substantial increase in the prevalence of HIV-1 infection between the beginning and the end of the survey period. Although there was a low prevalence of HIV-1 infection among military personnel and among women seen at prenatal clinics, a "low but rising prevalence of HIV-1 antibody" among military personnel points to a potential increase in the general population. "The fact that many HIV-1 antibody-positive men were married and reported bisexual behavior (28%) highlights the potential of this group to transmit HIV-1 to female partners," he added.

  5. [Sensitivity of the COBAS AmpliScreen™ HIV-1 test v1.5 for HIV-1 detection].

    PubMed

    Gomez, Lucía P; Balangero, Marcos C; Castro, Gonzalo; Kademian, Silvia; Mangeaud, Arnaldo; Barbas, María G; Cudolá, Analía; de León, Juan F; Carrizo, Horacio; Gallego, Sandra V

    2014-01-01

    The introduction of nucleic acid amplification techniques (NAT) in blood banks was intended to reduce the residual risk of transfusion-transmitted infections. Co-circulation of a great diversity of HIV-1 variants in Argentina portrays the need to assess the sensitivity of serological and molecular assays available for their detection. In this study, we evaluated the sensitivity of the COBAS AmpliScreen™ HIV-1 Test, version 1.5 (Roche) for the detection of HIV-1 RNA in plasma samples of infected individuals from Argentina. The results of this study reveal that this technique has high sensitivity for the detection of HIV-1 RNA under assay conditions: using mini-pool testing, pools ≥ 50 RNA copies per ml achieved ≥ 92 % sensitivity, whereas in the standard procedure, samples ≥ 207 RNA copies/ml achieved 100 % sensitivity. Moreover, the COBAS AmpliScreen™ HIV-1 Test, version 1.5 (Roche) is suitable for detecting prevailing HIV-1 variants.

  6. Sensitive HIV-1 detection in a homogeneous solution based on an electrochemical molecular beacon coupled with a nafion-graphene composite film modified screen-printed carbon electrode.

    PubMed

    Li, Bo; Li, Zhengliang; Situ, Bo; Dai, Zong; Liu, Qinlan; Wang, Qian; Gu, Dayong; Zheng, Lei

    2014-02-15

    A novel electrochemical sensing assay for sensitive determination of HIV-1 in a homogeneous solution has been developed using an electrochemical molecular beacon combined with a nafion-graphene composite film modified screen-printed carbon electrode (nafion-graphene/SPCE). The electrochemical molecular beacon (CAs-MB), comprising a special recognition sequence for the conserved region of the HIV-1 gag gene and a pair of carminic acid molecules as a marker, can indicate the presence of the HIV-1 target by its on/off electrochemical signal behavior. It is suitable for direct, electrochemical determination of HIV-1, thereby simplifying the detection procedure and improving the signal-to-noise (S/N) ratio. To further improve the sensitivity, the nafion-graphene/SPCE was used to monitor changes in the CAs-MB, which has notable advantages, such as being ultrasensitive, inexpensive, and disposable. Under optimized conditions, the peak currents showed a linear relationship with the logarithm of target oligonucleotide concentrations ranging from 40 nM to 2.56 μM, with a detection limit of 5 nM (S/N=3). This sensing assay also displays a good stability, with a recovery of 88-106.8% and RSD<7% (n=5) in real serum samples. This work may lead to the development of an effective method for early point-of-care diagnosis of HIV-1 infection. PMID:24099877

  7. Sensitive HIV-1 detection in a homogeneous solution based on an electrochemical molecular beacon coupled with a nafion-graphene composite film modified screen-printed carbon electrode.

    PubMed

    Li, Bo; Li, Zhengliang; Situ, Bo; Dai, Zong; Liu, Qinlan; Wang, Qian; Gu, Dayong; Zheng, Lei

    2014-02-15

    A novel electrochemical sensing assay for sensitive determination of HIV-1 in a homogeneous solution has been developed using an electrochemical molecular beacon combined with a nafion-graphene composite film modified screen-printed carbon electrode (nafion-graphene/SPCE). The electrochemical molecular beacon (CAs-MB), comprising a special recognition sequence for the conserved region of the HIV-1 gag gene and a pair of carminic acid molecules as a marker, can indicate the presence of the HIV-1 target by its on/off electrochemical signal behavior. It is suitable for direct, electrochemical determination of HIV-1, thereby simplifying the detection procedure and improving the signal-to-noise (S/N) ratio. To further improve the sensitivity, the nafion-graphene/SPCE was used to monitor changes in the CAs-MB, which has notable advantages, such as being ultrasensitive, inexpensive, and disposable. Under optimized conditions, the peak currents showed a linear relationship with the logarithm of target oligonucleotide concentrations ranging from 40 nM to 2.56 μM, with a detection limit of 5 nM (S/N=3). This sensing assay also displays a good stability, with a recovery of 88-106.8% and RSD<7% (n=5) in real serum samples. This work may lead to the development of an effective method for early point-of-care diagnosis of HIV-1 infection.

  8. HIV-1 infection in Juba, southern Sudan.

    PubMed

    McCarthy, M C; Khalid, I O; El Tigani, A

    1995-05-01

    Thirty years of civil war in the Sudan have resulted in the isolation of the southern provinces which border Central and East Africa. Consequently, little is known about the epidemiology of HIV-1 infection in this region. To estimate the prevalence of HIV-1 infection in southern Sudan and the risk factors associated with disease transmission, a seroepidemiologic survey was conducted in the township of Juba. Study subjects invited to participate in this study included medical outpatients, inpatients hospitalized for active tuberculosis, and female prostitutes. A total of 401 subjects participated in the study. HIV-1 infection was confirmed in 25 subjects. The prevalence of HIV-1 infection was 19% (8/42) among tuberculosis patients, 16% (8/50) among prostitutes, and 3% (9/309) among outpatients. A significantly higher prevalence of HIV-1 infection was found among female prostitutes when compared to female outpatients: 16% (8/50) vs. 2% (4/178), P < 0.001. Correspondingly, the prevalence of seropositives was significantly higher among male outpatients reporting a history of sexual relations with prostitutes during the prior 10 years compared to male outpatients denying relations with prostitutes: 14% (5/37) vs. 0% (0/94), P = 0.0011. A history of a sexually transmitted disease (STD) was also associated with HIV-1 infection among male outpatients. The findings of this study indicate that HIV-1 infection is highly prevalent in southern Sudan and that prostitutes and their sexual partners represent a major reservoir of HIV infection in this population. This epidemiologic pattern resembles that seen in the African nations neighboring southern Sudan.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. HIV-1 differentially modulates autophagy in neurons and astrocytes.

    PubMed

    Mehla, Rajeev; Chauhan, Ashok

    2015-08-15

    Autophagy, a lysosomal degradative pathway that maintains cellular homeostasis, has emerged as an innate immune defense against pathogens. The role of autophagy in the deregulated HIV-infected central nervous system (CNS) is unclear. We have found that HIV-1-induced neuro-glial (neurons and astrocytes) damage involves modulation of the autophagy pathway. Neuro-glial stress induced by HIV-1 led to biochemical and morphological dysfunctions. X4 HIV-1 produced neuro-glial toxicity coupled with suppression of autophagy, while R5 HIV-1-induced toxicity was restricted to neurons. Rapamycin, a specific mTOR inhibitor (autophagy inducer) relieved the blockage of the autophagy pathway caused by HIV-1 and resulted in neuro-glial protection. Further understanding of the regulation of autophagy by cytokines and chemokines or other signaling events may lead to recognition of therapeutic targets for neurodegenerative diseases.

  10. HIV-1 Capsid Stabilization Assay.

    PubMed

    Fricke, Thomas; Diaz-Griffero, Felipe

    2016-01-01

    The stability of the HIV-1 core in the cytoplasm is crucial for productive HIV-1 infection. Mutations that stabilize or destabilize the core showed defects in HIV-1 reverse transcription and infection. We developed a novel and simple assay to measure stability of in vitro-assembled HIV-1 CA-NC complexes. This assay allowed us to demonstrate that cytosolic extracts strongly stabilize the HIV-1 core (Fricke et al., J Virol 87:10587-10597, 2013). By using our novel assay, one can measure the ability of different drugs to modulate the stability of in vitro-assembled HIV-1 CA-NC complexes, such as PF74, CAP-1, IXN-053, cyclosporine A, Bi2, and the peptide CAI. We also found that purified CPSF6 (1-321) protein stabilizes in vitro-assembled HIV-1 CA-NC complexes (Fricke et al., J Virol 87:10587-10597, 2013). Here we describe in detail the use of this capsid stability assay. We believe that our assay can be a powerful tool to assess HIV-1 capsid stability in vitro.

  11. Association of HIV-1 Envelope-Specific Breast Milk IgA Responses with Reduced Risk of Postnatal Mother-to-Child Transmission of HIV-1

    PubMed Central

    Pollara, Justin; McGuire, Erin; Fouda, Genevieve G.; Rountree, Wes; Eudailey, Josh; Overman, R. Glenn; Seaton, Kelly E.; Deal, Aaron; Edwards, R. Whitney; Tegha, Gerald; Kamwendo, Deborah; Kumwenda, Jacob; Nelson, Julie A. E.; Liao, Hua-Xin; Brinkley, Christie; Denny, Thomas N.; Ochsenbauer, Christina; Ellington, Sascha; King, Caroline C.; Jamieson, Denise J.; van der Horst, Charles; Kourtis, Athena P.; Tomaras, Georgia D.; Ferrari, Guido

    2015-01-01

    ABSTRACT Infants born to HIV-1-infected mothers in resource-limited areas where replacement feeding is unsafe and impractical are repeatedly exposed to HIV-1 throughout breastfeeding. Despite this, the majority of infants do not contract HIV-1 postnatally, even in the absence of maternal antiretroviral therapy. This suggests that immune factors in breast milk of HIV-1-infected mothers help to limit vertical transmission. We compared the HIV-1 envelope-specific breast milk and plasma antibody responses of clade C HIV-1-infected postnatally transmitting and nontransmitting mothers in the control arm of the Malawi-based Breastfeeding Antiretrovirals and Nutrition Study using multivariable logistic regression modeling. We found no association between milk or plasma neutralization activity, antibody-dependent cell-mediated cytotoxicity, or HIV-1 envelope-specific IgG responses and postnatal transmission risk. While the envelope-specific breast milk and plasma IgA responses also did not reach significance in predicting postnatal transmission risk in the primary model after correction for multiple comparisons, subsequent exploratory analysis using two distinct assay methodologies demonstrated that the magnitudes of breast milk total and secretory IgA responses against a consensus HIV-1 envelope gp140 (B.con env03) were associated with reduced postnatal transmission risk. These results suggest a protective role for mucosal HIV-1 envelope-specific IgA responses in the context of postnatal virus transmission. This finding supports further investigations into the mechanisms by which mucosal IgA reduces risk of HIV-1 transmission via breast milk and into immune interventions aimed at enhancing this response. IMPORTANCE Infants born to HIV-1-infected mothers are repeatedly exposed to the virus in breast milk. Remarkably, the transmission rate is low, suggesting that immune factors in the breast milk of HIV-1-infected mothers help to limit transmission. We compared the antibody

  12. Selection bias at the heterosexual HIV-1 transmission bottleneck

    PubMed Central

    Carlson, Jonathan M.; Schaefer, Malinda; Monaco, Daniela C.; Batorsky, Rebecca; Claiborne, Daniel T.; Prince, Jessica; Deymier, Martin J.; Ende, Zachary S.; Klatt, Nichole R.; DeZiel, Charles E.; Lin, Tien-Ho; Peng, Jian; Seese, Aaron M.; Shapiro, Roger; Frater, John; Ndung’u, Thumbi; Tang, Jianming; Goepfert, Paul; Gilmour, Jill; Price, Matt A.; Kilembe, William; Heckerman, David; Goulder, Philip J.R.; Allen, Todd M.; Allen, Susan; Hunter, Eric

    2014-01-01

    SUMMARY Introduction Heterosexual HIV-1 transmission is an inefficient process with rates reported at <1% per unprotected sexual exposure. When transmission occurs, systemic infection is typically established by a single genetic variant, taken from the swarm of genetically distinct viruses circulating in the donor. Whether that founder virus represents a chance event or was systematically favored is unclear. Our work has tested a central hypothesis that founder virus selection is biased toward certain genetic characteristics. Rationale If HIV-1 transmission involves selection for viruses with certain favorable characteristics, then such advantages should emerge as statistical biases when viewed across many viral loci in many transmitting partners. We therefore identified 137 Zambian heterosexual transmission pairs, for whom plasma samples were available for both the donor and recipient partner soon after transmission, and compared the viral sequences obtained from each partner to identify features that predicted whether the majority amino acid observed at any particular position in the donor was transmitted. We focused attention on two features: viral genetic characteristics that correlate with viral fitness, and clinical factors that influence transmission. Statistical modeling indicates that the former will be favored for transmission, while the latter will nullify this relative advantage. Results We observed a highly significant selection bias that favors the transmission of amino acids associated with increased fitness. These features included the frequency of the amino acid in the study cohort, the relative advantage of the amino acid with respect to the stability of the protein, and features related to immune escape and compensation. This selection bias was reduced in couples with high risk of transmission. In particular, significantly less selection bias was observed in women and in men with genital inflammation, compared to healthy men, suggesting a more

  13. HIV-1 subtype characteristics of infected persons living in southwestern Greece

    PubMed Central

    Davanos, Nikolaos; Panos, George; Gogos, Charalambos A; Mouzaki, Athanasia

    2015-01-01

    Background The rapid replication rate of HIV-1, coupled with a high mutation rate and recombination, is the underlying force driving its genetic diversity. In the infected individual, a population of highly related but nonidentical strains exists. At the population level, multiple subtypes often cocirculate, leading to the generation of intersubtype recombinant forms. As a result, the geographic distribution of subtypes and recombinant forms is complex and uneven. Genetic subtyping of HIV-1 isolates has been shown to be helpful for understanding the genetic evolution, the worldwide spread of the virus, and the evaluation of drug resistance. Materials and methods We determined the genetic heterogeneity of HIV-1 group M in southwestern Greece. Protease and partial reverse-transcriptase sequences were generated from 150 HIV-1-infected individuals attending the Division of Infectious Diseases of Patras University Hospital, Greece, from 2006 to 2012, and analyzed using online subtyping tools and phylogenetic methods. Results The majority of the infected individuals were male (77%). HIV-1 subtype A1 was responsible for 51.3% of infections, followed by subtypes B (34%), G (4%), F1 (2%), and the circulating recombinant forms 02_AG (2.7%), 14_BG (1.3%), 35_AD (1.3%), and 01_AE (0.7%). Additionally, we identified three cases with a recombinant B/CRF02_AG strain (2%) and one with a recombinant G/GRF_AG strain. Sexual transmission was responsible for 96.3% of cases. Heterosexual transmission was responsible for 70.2% of subtype-A1 infections, whereas subtype B was transmitted by men who have sex with men in 75.5% of cases. Protease substitutions I13V, E35D, M36I, R57K, H69K, and L89M, which serve as drug-resistance support mutations in subtype B, were present in the majority of subtype-A1 sequences of the population. Conclusion HIV-1 infection in southwestern Greece is sexually transmitted and highly heterogeneous. Subtype A1 has surpassed subtype B, and is the most prevalent

  14. Hyperthermia Stimulates HIV-1 Replication

    PubMed Central

    Roesch, Ferdinand; Meziane, Oussama; Kula, Anna; Nisole, Sébastien; Porrot, Françoise; Anderson, Ian; Mammano, Fabrizio; Fassati, Ariberto; Marcello, Alessandro; Benkirane, Monsef; Schwartz, Olivier

    2012-01-01

    HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42–45°C) and Heat Shock Proteins (HSPs) modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38–40°C) on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C) increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity. PMID:22807676

  15. Defining the roles for Vpr in HIV-1-associated neuropathogenesis.

    PubMed

    James, Tony; Nonnemacher, Michael R; Wigdahl, Brian; Krebs, Fred C

    2016-08-01

    It is increasingly evident that the human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) has a unique role in neuropathogenesis. Its ability to induce G2/M arrest coupled with its capacity to increase viral gene transcription gives it a unique role in sustaining viral replication and aiding in the establishment and maintenance of a systemic infection. The requirement of Vpr for HIV-1 infection and replication in cells of monocytic origin (a key lineage of cells involved in HIV-1 neuroinvasion) suggests an important role in establishing and sustaining infection in the central nervous system (CNS). Contributions of Vpr to neuropathogenesis can be expanded further through (i) naturally occurring HIV-1 sequence variation that results in functionally divergent Vpr variants; (ii) the dual activities of Vpr as a intracellular protein delivered and expressed during HIV-1 infection and as an extracellular protein that can act on neighboring, uninfected cells; (iii) cell type-dependent consequences of Vpr expression and exposure, including cell cycle arrest, metabolic dysregulation, and cytotoxicity; and (iv) the effects of Vpr on exosome-based intercellular communication in the CNS. Revealing that the effects of this pleiotropic viral protein is an essential part of a greater understanding of HIV-1-associated pathogenesis and potential approaches to treating and preventing disease caused by HIV-1 infection.

  16. Defining the roles for Vpr in HIV-1-associated neuropathogenesis.

    PubMed

    James, Tony; Nonnemacher, Michael R; Wigdahl, Brian; Krebs, Fred C

    2016-08-01

    It is increasingly evident that the human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) has a unique role in neuropathogenesis. Its ability to induce G2/M arrest coupled with its capacity to increase viral gene transcription gives it a unique role in sustaining viral replication and aiding in the establishment and maintenance of a systemic infection. The requirement of Vpr for HIV-1 infection and replication in cells of monocytic origin (a key lineage of cells involved in HIV-1 neuroinvasion) suggests an important role in establishing and sustaining infection in the central nervous system (CNS). Contributions of Vpr to neuropathogenesis can be expanded further through (i) naturally occurring HIV-1 sequence variation that results in functionally divergent Vpr variants; (ii) the dual activities of Vpr as a intracellular protein delivered and expressed during HIV-1 infection and as an extracellular protein that can act on neighboring, uninfected cells; (iii) cell type-dependent consequences of Vpr expression and exposure, including cell cycle arrest, metabolic dysregulation, and cytotoxicity; and (iv) the effects of Vpr on exosome-based intercellular communication in the CNS. Revealing that the effects of this pleiotropic viral protein is an essential part of a greater understanding of HIV-1-associated pathogenesis and potential approaches to treating and preventing disease caused by HIV-1 infection. PMID:27056720

  17. Authentic HIV-1 integrase inhibitors

    PubMed Central

    Liao, Chenzhong; Marchand, Christophe; Burke, Terrence R; Pommier, Yves; Nicklaus, Marc C

    2010-01-01

    HIV-1 integrase (IN) is indispensable for HIV-1 replication and has become a validated target for developing anti-AIDS agents. In two decades of development of IN inhibition-based anti-HIV therapeutics, a significant number of compounds were identified as IN inhibitors, but only some of them showed antiviral activity. This article reviews a number of patented HIV-1 IN inhibitors, especially those that possess high selectivity for the strand transfer reaction. These compounds generally have a polar coplanar moiety, which is assumed to chelate two magnesium ions in the binding site. Resistance to those compounds, when given to patients, can develop as a result of IN mutations. We refer to those compounds as authentic IN inhibitors. Continued drug development has so far delivered one authentic IN inhibitor to the market (raltegravir in 2007). Current and future attention will be focused on the development of novel authentic IN inhibitors with the goal of overcoming viral resistance. PMID:21426159

  18. HIV-1 antiretroviral drug therapy.

    PubMed

    Arts, Eric J; Hazuda, Daria J

    2012-04-01

    The most significant advance in the medical management of HIV-1 infection has been the treatment of patients with antiviral drugs, which can suppress HIV-1 replication to undetectable levels. The discovery of HIV-1 as the causative agent of AIDS together with an ever-increasing understanding of the virus replication cycle have been instrumental in this effort by providing researchers with the knowledge and tools required to prosecute drug discovery efforts focused on targeted inhibition with specific pharmacological agents. To date, an arsenal of 24 Food and Drug Administration (FDA)-approved drugs are available for treatment of HIV-1 infections. These drugs are distributed into six distinct classes based on their molecular mechanism and resistance profiles: (1) nucleoside-analog reverse transcriptase inhibitors (NNRTIs), (2) non-nucleoside reverse transcriptase inhibitors (NNRTIs), (3) integrase inhibitors, (4) protease inhibitors (PIs), (5) fusion inhibitors, and (6) coreceptor antagonists. In this article, we will review the basic principles of antiretroviral drug therapy, the mode of drug action, and the factors leading to treatment failure (i.e., drug resistance).

  19. Prevalence of HIV-1 in east African lorry drivers.

    PubMed

    Carswell, J W; Lloyd, G; Howells, J

    1989-11-01

    Sixty-eight lorry drivers and their assistants were examined for evidence of infection with HIV-1 because of their association and regular contact with prostitutes. Out of a total of 68 drivers, 24 (35.2%) were serologically found to be HIV-1 positive. Epidemiological evidence demonstrated a wide travel history involving seven different countries served by the port of Mombasa. History of other sexually transmitted disorders were significantly higher in HIV-seropositive individuals. The data presented here further support the hypothesis that a major route of heterosexual transmission of HIV in Africa is dissemination through a group such as lorry drivers and their assistants, whose behaviour puts them at risk of acquiring sexually transmitted diseases. PMID:2515882

  20. Pandemic HIV-1 Vpu overcomes intrinsic herd immunity mediated by tetherin.

    PubMed

    Iwami, Shingo; Sato, Kei; Morita, Satoru; Inaba, Hisashi; Kobayashi, Tomoko; Takeuchi, Junko S; Kimura, Yuichi; Misawa, Naoko; Ren, Fengrong; Iwasa, Yoh; Aihara, Kazuyuki; Koyanagi, Yoshio

    2015-07-17

    Among the four groups of HIV-1 (M, N, O, and P), HIV-1M alone is pandemic and has rapidly expanded across the world. However, why HIV-1M has caused a devastating pandemic while the other groups remain contained is unclear. Interestingly, only HIV-1M Vpu, a viral protein, can robustly counteract human tetherin, which tethers budding virions. Therefore, we hypothesize that this property of HIV-1M Vpu facilitates human-to-human viral transmission. Adopting a multilayered experimental-mathematical approach, we demonstrate that HIV-1M Vpu confers a 2.38-fold increase in the prevalence of HIV-1 transmission. When Vpu activity is lost, protected human populations emerge (i.e., intrinsic herd immunity develops) through the anti-viral effect of tetherin. We also reveal that all Vpus of transmitted/founder HIV-1M viruses maintain anti-tetherin activity. These findings indicate that tetherin plays the role of a host restriction factor, providing 'intrinsic herd immunity', whereas Vpu has evolved in HIV-1M as a tetherin antagonist.

  1. Maternal HIV-1 envelope–specific antibody responses and reduced risk of perinatal transmission

    PubMed Central

    Permar, Sallie R.; Fong, Youyi; Vandergrift, Nathan; Fouda, Genevieve G.; Gilbert, Peter; Parks, Robert; Jaeger, Frederick H.; Pollara, Justin; Martelli, Amanda; Liebl, Brooke E.; Lloyd, Krissey; Yates, Nicole L.; Overman, R. Glenn; Shen, Xiaoying; Whitaker, Kaylan; Chen, Haiyan; Pritchett, Jamie; Solomon, Erika; Friberg, Emma; Marshall, Dawn J.; Whitesides, John F.; Gurley, Thaddeus C.; Von Holle, Tarra; Martinez, David R.; Cai, Fangping; Kumar, Amit; Xia, Shi-Mao; Lu, Xiaozhi; Louzao, Raul; Wilkes, Samantha; Datta, Saheli; Sarzotti-Kelsoe, Marcella; Liao, Hua-Xin; Ferrari, Guido; Alam, S. Munir; Montefiori, David C.; Denny, Thomas N.; Moody, M. Anthony; Tomaras, Georgia D.; Gao, Feng; Haynes, Barton F.

    2015-01-01

    Despite the wide availability of antiretroviral drugs, more than 250,000 infants are vertically infected with HIV-1 annually, emphasizing the need for additional interventions to eliminate pediatric HIV-1 infections. Here, we aimed to define humoral immune correlates of risk of mother-to-child transmission (MTCT) of HIV-1, including responses associated with protection in the RV144 vaccine trial. Eighty-three untreated, HIV-1transmitting mothers and 165 propensity score–matched nontransmitting mothers were selected from the Women and Infants Transmission Study (WITS) of US nonbreastfeeding, HIV-1–infected mothers. In a multivariable logistic regression model, the magnitude of the maternal IgG responses specific for the third variable loop (V3) of the HIV-1 envelope was predictive of a reduced risk of MTCT. Neutralizing Ab responses against easy-to-neutralize (tier 1) HIV-1 strains also predicted a reduced risk of peripartum transmission in secondary analyses. Moreover, recombinant maternal V3–specific IgG mAbs mediated neutralization of autologous HIV-1 isolates. Thus, common V3-specific Ab responses in maternal plasma predicted a reduced risk of MTCT and mediated autologous virus neutralization, suggesting that boosting these maternal Ab responses may further reduce HIV-1 MTCT. PMID:26053661

  2. Curcumin derivatives as HIV-1 protease inhibitors

    SciTech Connect

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R.

    1993-12-31

    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  3. Incidence, Prevalence and Epidemiology of Herpes Simplex Virus-2 in HIV-1-positive and HIV-1-negative Adolescents

    PubMed Central

    Sudenga, Staci L.; Kempf, Mirjam-Colette; McGwin, Gerald; Wilson, Craig M.; Hook, Edward; Shrestha, Sadeep

    2012-01-01

    Background Several studies have assessed risk factors associated with herpes simplex virus-2 (HSV-2) prevalence in adults; however, few have focused on HSV-2 incidence, particularly in adolescents. The objective of this study was to determine HSV-2 prevalence and incidence and associated risk factors in a HIV-1-positive and at risk HIV-1-negative adolescent population. Methods Sera were tested for HSV-2 antibodies in 518 adolescents in the Reaching for Excellence in Adolescent Care and Health (REACH) cohort at baseline and again at the final follow-up visit. Prevalence at baseline and incidence (per person years) of HSV-2 infection were calculated. Furthermore, among HIV-1-positive individuals, a subgroup analysis was performed to assess risk factors for HSV-2 infection. Conditional logistic regression was used to estimate odds ratios (OR) and p-values (p) for associations between CD4+ T-cell (CD4+) count, HIV-1 viral load (VL), and HSV-2 acquisition, adjusting for antiretroviral therapy use, other sexually transmitted infections, gender, race, and number of sexual partners. Results At baseline, 179 (35%) subjects were HSV-2 positive, with an additional 47 (16%) new cases being identified during a median follow-up time of 1.95 years and an incidence rate of 7.35 cases per 100 person years (py). Several risk factors were associated with HSV-2 prevalence (being female, non-Hispanic, uncertainty of sexual preference, and HIV-1 positive) and incidence (using drugs, alcohol, and number of new sexual partners). Among HIV-1 positives, an increase in CD4+ count by 50 cell/mm3 (OR, 1.17; 95% CI 1.04–1.31, p=0.008) was associated with HSV-2 acquisition. Conclusions The high prevalence and incidence of HSV-2 infection among adolescents, compared to the general population at this age group suggests a critical need for screening and preventive programs among this targeted group. PMID:22421698

  4. Ultrasonic input-output for transmitting and receiving longitudinal transducers coupled to same face of isotropic elastic plate

    NASA Technical Reports Server (NTRS)

    Williams, J. H., Jr.; Karagulle, H.; Lee, S. S.

    1982-01-01

    The quantitative understanding of ultrasonic nondestructive evaluation parameters such as the stress wave factor were studied. Ultrasonic input/output characteristics for an isotropic elastic plate with transmitting and receiving longitudinal transducers coupled to the same face were analyzed. The asymptotic normal stress is calculated for an isotropic elastic half space subjected to a uniform harmonic normal stress applied to a circular region at the surface. The radiated stress waves are traced within the plate by considering wave reflections at the top and bottom faces. The output voltage amplitude of the receiving transducer is estimated by considering only longitudinal waves. Agreement is found between the output voltage wave packet amplitudes and times of arrival due to multiple reflections of the longitudinal waves.

  5. Assessment by gene amplification and serological markers of transmission of HIV-1 from hemophiliacs to their sexual partners and secondarily to their children.

    PubMed

    Hewlett, I K; Laurian, Y; Epstein, J; Hawthorne, C A; Ruta, M; Allain, J P

    1990-01-01

    The transmission of HIV-1 infection from men with hemophilia A to their female sex partners and secondarily to their children was studied by serological markers including antibody, antigen, and HIV genome as detected by the polymerase chain reaction (PCR). Among 27 sex partners of 26 seropositive hemophiliacs, 5 were seropositive-PCR positive (active), 11 were seronegative-PCR positive (latent), and 11 were negative for both. These results were confirmed by testing serial serum samples and paired samples of DNA from peripheral blood mononuclear cells (PBMCs) and serum from seronegative women. PCR negativity in exposed women was correlated with the use of condoms (p less than 0.01). Eight children from five couples were seronegative. However, HIV-1 infection as detected by PCR was transmitted to 60% of exposed children, including one from a seronegative-PCR positive mother. PMID:2352123

  6. C-type lectin Mermaid inhibits dendritic cell mediated HIV-1 transmission to CD4+ T cells.

    PubMed

    Nabatov, Alexey A; de Jong, Marein A W P; de Witte, Lot; Bulgheresi, Silvia; Geijtenbeek, Teunis B H

    2008-09-01

    Dendritic cells (DCs) are important in HIV-1 transmission; DCs capture invading HIV-1 through the interaction of the gp120 oligosaccharides with the C-type lectin DC-SIGN and migrate to the lymphoid tissues where HIV-1 is transmitted to T cells. Thus, the HIV-1 envelope glycoprotein gp120 is an attractive target to prevent interactions with DCs and subsequent viral transmission. Here, we have investigated whether the structural homologue of DC-SIGN, the nematode C-type lectin Mermaid can be used to prevent HIV-1 transmission by DCs. Our data demonstrate that Mermaid interacts with high mannose structures present on HIV-1 gp120 and thereby inhibits HIV-1 binding to DC-SIGN on DCs. Moreover, Mermaid inhibits DC-SIGN-mediated HIV-1 transmission from DC to T cells. We have identified Mermaid as a non-cytotoxic agent that shares the glycan specificity with DC-SIGN and inhibits DC-SIGN-gp120 interaction. The results are important for the anti-HIV-1 microbicide development directed at preventing DC-HIV-1 interactions. PMID:18597806

  7. Vpu-Mediated Counteraction of Tetherin Is a Major Determinant of HIV-1 Interferon Resistance

    PubMed Central

    Kmiec, Dorota; Iyer, Shilpa S.; Stürzel, Christina M.; Sauter, Daniel; Hahn, Beatrice H.

    2016-01-01

    ABSTRACT Human immunodeficiency virus type 1 (HIV-1) groups M, N, O, and P are the result of independent zoonotic transmissions of simian immunodeficiency viruses (SIVs) infecting great apes in Africa. Among these, only Vpu proteins of pandemic HIV-1 group M strains evolved potent activity against the restriction factor tetherin, which inhibits virus release from infected cells. Thus, effective Vpu-mediated tetherin antagonism may have been a prerequisite for the global spread of HIV-1. To determine whether this particular function enhances primary HIV-1 replication and interferon resistance, we introduced mutations into the vpu genes of HIV-1 group M and N strains to specifically disrupt their ability to antagonize tetherin, but not other Vpu functions, such as degradation of CD4, down-modulation of CD1d and NTB-A, and suppression of NF-κB activity. Lack of particular human-specific adaptations reduced the ability of HIV-1 group M Vpu proteins to enhance virus production and release from primary CD4+ T cells at high levels of type I interferon (IFN) from about 5-fold to 2-fold. Interestingly, transmitted founder HIV-1 strains exhibited higher virion release capacity than chronic control HIV-1 strains irrespective of Vpu function, and group M viruses produced higher levels of cell-free virions than an N group HIV-1 strain. Thus, efficient virus release from infected cells seems to play an important role in the spread of HIV-1 in the human population and requires a fully functional Vpu protein that counteracts human tetherin. PMID:27531907

  8. Macrophages and HIV-1: An Unhealthy Constellation.

    PubMed

    Sattentau, Quentin J; Stevenson, Mario

    2016-03-01

    Lentiviruses have a long-documented association with macrophages. Abundant evidence exists for in vitro and, in a tissue-specific manner, in vivo infection of macrophages by the primate lentiviruses HIV-1 and SIV. However, macrophage contribution to aspects of HIV-1 and SIV pathogenesis, and their role in viral persistence in individuals on suppressive antiretroviral therapy, remains unclear. Here we discuss recent evidence implicating macrophages in HIV-1-mediated disease and highlight directions for further investigation.

  9. Antiretroviral Therapy for the Prevention of HIV-1 Transmission.

    PubMed

    Cohen, Myron S; Chen, Ying Q; McCauley, Marybeth; Gamble, Theresa; Hosseinipour, Mina C; Kumarasamy, Nagalingeswaran; Hakim, James G; Kumwenda, Johnstone; Grinsztejn, Beatriz; Pilotto, Jose H S; Godbole, Sheela V; Chariyalertsak, Suwat; Santos, Breno R; Mayer, Kenneth H; Hoffman, Irving F; Eshleman, Susan H; Piwowar-Manning, Estelle; Cottle, Leslie; Zhang, Xinyi C; Makhema, Joseph; Mills, Lisa A; Panchia, Ravindre; Faesen, Sharlaa; Eron, Joseph; Gallant, Joel; Havlir, Diane; Swindells, Susan; Elharrar, Vanessa; Burns, David; Taha, Taha E; Nielsen-Saines, Karin; Celentano, David D; Essex, Max; Hudelson, Sarah E; Redd, Andrew D; Fleming, Thomas R

    2016-09-01

    Background An interim analysis of data from the HIV Prevention Trials Network (HPTN) 052 trial showed that antiretroviral therapy (ART) prevented more than 96% of genetically linked infections caused by human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. ART was then offered to all patients with HIV-1 infection (index participants). The study included more than 5 years of follow-up to assess the durability of such therapy for the prevention of HIV-1 transmission. Methods We randomly assigned 1763 index participants to receive either early or delayed ART. In the early-ART group, 886 participants started therapy at enrollment (CD4+ count, 350 to 550 cells per cubic millimeter). In the delayed-ART group, 877 participants started therapy after two consecutive CD4+ counts fell below 250 cells per cubic millimeter or if an illness indicative of the acquired immunodeficiency syndrome (i.e., an AIDS-defining illness) developed. The primary study end point was the diagnosis of genetically linked HIV-1 infection in the previously HIV-1-negative partner in an intention-to-treat analysis. Results Index participants were followed for 10,031 person-years; partners were followed for 8509 person-years. Among partners, 78 HIV-1 infections were observed during the trial (annual incidence, 0.9%; 95% confidence interval [CI], 0.7 to 1.1). Viral-linkage status was determined for 72 (92%) of the partner infections. Of these infections, 46 were linked (3 in the early-ART group and 43 in the delayed-ART group; incidence, 0.5%; 95% CI, 0.4 to 0.7) and 26 were unlinked (14 in the early-ART group and 12 in the delayed-ART group; incidence, 0.3%; 95% CI, 0.2 to 0.4). Early ART was associated with a 93% lower risk of linked partner infection than was delayed ART (hazard ratio, 0.07; 95% CI, 0.02 to 0.22). No linked infections were observed when HIV-1 infection was stably suppressed by ART in the index participant. Conclusions The early initiation of ART led to a sustained

  10. Longitudinal studies on maternal HIV-1 variants by biological phenotyping, sequence analysis and viral load.

    PubMed

    Renta, J Y; Cadilla, C L; Vega, M E; Hillyer, G V; Estrada, C; Jiménez, E; Abreu, E; Méndez, I; Gandía, J; Meléndez-Guerrero, L M

    1997-11-01

    In this study, the HIV-1 variant viruses from ten pregnant women and their infants were isolated and characterized longitudinally in order to determine the role that viral envelope (gp120-V3 loop) gene variation and viral tropism play in vertical transmission. Biological phenotyping of each HIV variant was accomplished by growth in MT-2, and macrophages from healthy and non-HIV-infected donors. Genetic characterization of the variants was accomplished by DNA sequence analysis. All the women enrolled in this study received ZDV therapy. Virus was cultured from eight out of ten env V3-PCR positive mothers. HIV-1 isolates were all non-syncitium inducing variants. None of the mothers were found to transmit HIV, as determined by DNA PCR and quantitative co-cultures on their infants which were seronegative for HIV-1 through one year after birth. Viral cultures from infant blood samples were negative and infants were all healthy. However, nested env V3-PCR detected proviral DNA in five out of ten infants. In contrast, conventional gag-PCR was negative in the same five infants. Sequences of the five maternal-infant pairs were different, suggesting unique infant HIV-1 variants. The three highest maternal viral load values corresponded to infants that were env V3-PCR positive. These results suggest that HIV-1 particles are transmitted from ZDV-treated mothers to infants. Infant follow up is recommended to determine if HIV-1 has been inhibited by the immune system of the infants.

  11. HIV-1 Reverse Transcriptase Drug-Resistance Mutations in Chronically Infected Individuals Receiving or Naïve to HAART in Cameroon

    PubMed Central

    Burda, Sherri T.; Viswanath, Ragupathy; Zhao, Jiangqin; Kinge, Thompson; Anyangwe, Christopher; Tinyami, Erick T.; Haldar, Bijayesh; Powell, Rebecca L.R.; Jarido, Veronica; Hewlett, Indira K.; Nyambi, Phillipe N.

    2010-01-01

    The most common first-line, highly active anti-retroviral therapy (HAART) received by individuals infected with HIV-1 in Cameroon is the combination therapy Triomune, comprised of two nucleoside reverse transcriptase inhibitors (NRTI) and one non-NRTI (NNRTI). To examine the efficacy of these drugs in Cameroon, where diverse non-B HIV-1 subtypes and recombinant viruses predominate, the reverse transcriptase (RT) viral sequences in patient plasma were analyzed for the presence of mutations that confer drug resistance. Forty-nine HIV-1-positive individuals were randomly selected from those receiving care in HIV/AIDS outpatient clinics in the South-West and North-West Regions of Cameroon. Among the 28 patients receiving HAART, 39% (11/28) had resistance to NRTIs, and 46% (13/28) to NNRTIs after a median of 12 months from the start of therapy. Among those with drug-resistance mutations, there was a median of 14 months from the start of HAART, versus 9 months for those without; no difference was observed in the average viral load (10,997 copies/ml vs. 8,056 copies/ml). In contrast, drug-naïve individuals had a significantly higher average viral load (27,929 copies/ml) than those receiving HAART (9,527 copies/ml). Strikingly, among the 21 drug-naïve individuals, 24% harbored viruses with drug-resistance mutations, suggesting that HIV-1 drug-resistant variants are being transmitted in Cameroon. Given the high frequency of resistance mutations among those on first-line HAART, coupled with the high prevalence of HIV-1 variants with drug-resistance mutations among drug-naïve individuals, this study emphasizes the need for extensive monitoring of resistance mutations and the introduction of a second-line HAART strategy in Cameroon. PMID:20029816

  12. Antiretroviral Prophylaxis for HIV-1 Prevention among Heterosexual Men and Women

    PubMed Central

    Baeten, Jared M.; Donnell, Deborah; Ndase, Patrick; Mugo, Nelly R.; Campbell, James D.; Wangisi, Jonathan; Tappero, Jordan W.; Bukusi, Elizabeth A.; Cohen, Craig R.; Katabira, Elly; Ronald, Allan; Tumwesigye, Elioda; Were, Edwin; Fife, Kenneth H.; Kiarie, James; Farquhar, Carey; John-Stewart, Grace; Kakia, Aloysious; Odoyo, Josephine; Mucunguzi, Akasiima; Nakku-Joloba, Edith; Twesigye, Rogers; Ngure, Kenneth; Apaka, Cosmas; Tamooh, Harrison; Gabona, Fridah; Mujugira, Andrew; Panteleeff, Dana; Thomas, Katherine K.; Kidoguchi, Lara; Krows, Meighan; Revall, Jennifer; Morrison, Susan; Haugen, Harald; Emmanuel-Ogier, Mira; Ondrejcek, Lisa; Coombs, Robert W.; Frenkel, Lisa; Hendrix, Craig; Bumpus, Namandjé N.; Bangsberg, David; Haberer, Jessica E.; Stevens, Wendy S.; Lingappa, Jairam R.; Celum, Connie

    2013-01-01

    Introduction Antiretroviral pre-exposure prophylaxis (PrEP) reduces the incidence of acquisition of human immunodeficiency virus type 1 (HIV-1) in men who have sex with men and is a promising approach for preventing HIV-1 in heterosexual populations. Methods We conducted a randomized, three-arm trial of oral antiretroviral PrEP among heterosexual couples from Kenya and Uganda in which one member was HIV-1 seronegative and the other HIV-1 seropositive. Seronegative partners were randomly assigned to once-daily tenofovir (TDF), combination emtricitabine/tenofovir (FTC/TDF), or matching placebo and followed monthly for up to 36 months. At enrollment, HIV-1 seropositive partners were not eligible for antiretroviral therapy under national guidelines. All couples received standard HIV-1 treatment and prevention services, including individual and couples risk-reduction counseling and condoms. Results 4758 couples were enrolled; for 62%, the HIV-1 seronegative partner was male. For HIV-1 seropositive participants, the median CD4 count was 495 cells/μL (interquartile range 375–662). Of 82 post-randomization HIV-1 infections, 17 were among those assigned TDF (incidence 0.65 per 100 person-years), 13 among those assigned FTC/TDF (incidence 0.50 per 100 person-years), and 52 among those assigned placebo (incidence 1.99 per 100 person-years), indicating a 67% relative reduction in HIV-1 incidence for TDF (95% CI 44 to 81, p<0.001) and 75% for FTC/TDF (95% CI 55 to 87, p<0.001). HIV-1 protective effects of FTC/TDF and TDF were not significantly different (p=0.23), and both study medications significantly reduced HIV-1 incidence in both men and women. The rate of serious medical events was similar across the study arms. Conclusions Oral TDF and FTC/TDF provided substantial protection against HIV-1 acquisition in heterosexual men and women, with comparable efficacy of TDF and FTC/TDF. (Funded by the Bill and Melinda Gates Foundation; ClinicalTrials.gov number NCT00557245) PMID

  13. In vitro anti-HIV-1 activity of salicylidene acylhydrazide compounds.

    PubMed

    Forthal, Donald N; Phan, Tran B; Slepenkin, Anatoly V; Landucci, Gary; Chu, Hencelyn; Elofsson, Mikael; Peterson, Ellena

    2012-10-01

    Salicylidene acylhydrazide compounds have been shown to inhibit bacterial pathogens, including Chlamydia and Neisseria gonorrhoeae. If such compounds could also target HIV-1, their potential use as topical microbicides to prevent sexually transmitted infections would be considerable. In this study, the in vitro anti-HIV-1 activity, cytotoxicity and mechanism of action of several salicylidene acylhydrazides were determined. Inhibitory activity was assessed using TZM-bl cells and primary peripheral blood mononuclear cells (PBMCs) as targets for HIV-1 infection. Antiviral activity was measured against cell-free and cell-associated virus and in vaginal fluid and semen simulants. Since the antibacterial activity of salicylidene acylhydrazides is reversible by Fe(2+), the ability of Fe(2+) and other cations to reverse the anti-HIV-1 activity of the compounds was determined. Real-time PCR was also employed to determine the stage affected in the HIV-1 replication cycle. Four compounds with 50% inhibitory concentrations against HIV-1 of 1-7 μM were identified. In vitro toxicity varied but was generally limited. Activity was similar against three R5 clade B primary isolates and whether the target for virus replication was TZM-bl cells or PBMCs. Compounds inhibited cell-free and cell-associated virus and were active in vaginal fluid and semen simulants. Fe(2+), but not other cations, reversed the anti-HIV-1 effect. Finally, the inhibitory effect of the compounds occurred at a post-integration step. In conclusion, salicylidene acylhydrazides were identified with in vitro anti-HIV-1 activity in the micromolar range. The activity of these compounds against other sexually transmitted pathogens makes them potential candidates to formulate for use as a broad-spectrum topical genital microbicide. PMID:22819150

  14. Drug-Eluting Fibers for HIV-1 Inhibition and Contraception

    PubMed Central

    Ball, Cameron; Krogstad, Emily; Chaowanachan, Thanyanan; Woodrow, Kim A.

    2012-01-01

    Multipurpose prevention technologies (MPTs) that simultaneously prevent sexually transmitted infections (STIs) and unintended pregnancy are a global health priority. Combining chemical and physical barriers offers the greatest potential to design effective MPTs, but integrating both functional modalities into a single device has been challenging. Here we show that drug-eluting fiber meshes designed for topical drug delivery can function as a combination chemical and physical barrier MPT. Using FDA-approved polymers, we fabricated nanofiber meshes with tunable fiber size and controlled degradation kinetics that facilitate simultaneous release of multiple agents against HIV-1, HSV-2, and sperm. We observed that drug-loaded meshes inhibited HIV-1 infection in vitro and physically obstructed sperm penetration. Furthermore, we report on a previously unknown activity of glycerol monolaurate (GML) to potently inhibit sperm motility and viability. The application of drug-eluting nanofibers for HIV-1 prevention and sperm inhibition may serve as an innovative platform technology for drug delivery to the lower female reproductive tract. PMID:23209601

  15. High-Throughput Humanized Mouse Models for Evaluation of HIV-1 Therapeutics and Pathogenesis.

    PubMed

    Thomas, Tynisha; Seay, Kieran; Zheng, Jian Hua; Zhang, Cong; Ochsenbauer, Christina; Kappes, John C; Goldstein, Harris

    2016-01-01

    Mice cannot be used as a model to evaluate HIV-1 therapeutics because they do not become infected by HIV-1 due to structural differences between several human and mouse proteins required for HIV-1 replication. This has limited their use for in vivo assessment of anti-HIV-1 therapeutics and the mechanism by which cofactors, such as illicit drug use accelerate HIV-1 replication and disease course in substance abusers. Here, we describe the development and application of two in vivo humanized mouse models that are highly sensitive and useful models for the in vivo evaluation of candidate anti-HIV therapeutics. The first model, hu-spl-PBMC-NSG mice, uses NOD-SCID IL2rγ(-/-) (NSG) mice intrasplenically injected with human peripheral blood mononuclear cells (PBMC) which develop productive splenic HIV-1 infection after intrasplenic inoculation with a replication-competent HIV-1 expressing Renilla reniformis luciferase (HIV-LucR) and enables investigators to use bioluminescence to visualize and quantitate the temporal effects of therapeutics on HIV-1 infection. The second model, hCD4/R5/cT1 mice, consists of transgenic mice carrying human CD4, CCR5 and cyclin T1 genes, which enables murine CD4-expressing cells to support HIV-1 entry, Tat-mediated LTR transcription and consequently develop productive infection. The hCD4/R5/cT1 mice develop disseminated infection of tissues including the spleen, small intestine, lymph nodes and lungs after intravenous injection with HIV-1-LucR. Because these mice can be infected with HIV-LucR expressing transmitted/founder and clade A/E and C Envs, these mouse models can also be used to evaluate the in vivo efficacy of broadly neutralizing antibodies and antibodies induced by candidate HIV-1 vaccines. Furthermore, because hCD4/R5/cT1 mice can be infected by vaginal inoculation with replication-competent HIV-1 expressing NanoLuc (HIV-nLucR)-, this mouse model can be used to evaluate the mechanisms by which substance abuse and other factors

  16. Multiploid inheritance of HIV-1 during cell-to-cell infection.

    PubMed

    Del Portillo, Armando; Tripodi, Joseph; Najfeld, Vesna; Wodarz, Dominik; Levy, David N; Chen, Benjamin K

    2011-07-01

    During cell-to-cell transmission of human immunodeficiency virus type 1 (HIV-1), many viral particles can be simultaneously transferred from infected to uninfected CD4 T cells through structures called virological synapses (VS). Here we directly examine how cell-free and cell-to-cell infections differ from infections initiated with cell-free virus in the number of genetic copies that are transmitted from one generation to the next, i.e., the genetic inheritance. Following exposure to HIV-1-expressing cells, we show that target cells with high viral uptake are much more likely to become infected. Using T cells that coexpress distinct fluorescent HIV-1 variants, we show that multiple copies of HIV-1 can be cotransmitted across a single VS. In contrast to cell-free HIV-1 infection, which titrates with Poisson statistics, the titration of cell-associated HIV-1 to low rates of overall infection generates a constant fraction of the newly infected cells that are cofluorescent. Triple infection was also readily detected when cells expressing three fluorescent viruses were used as donor cells. A computational model and a statistical model are presented to estimate the degree to which cofluorescence underestimates coinfection frequency. Lastly, direct detection of HIV-1 proviruses using fluorescence in situ hybridization confirmed that significantly more HIV-1 DNA copies are found in primary T cells infected with cell-associated virus than in those infected with cell-free virus. Together, the data suggest that multiploid inheritance is common during cell-to-cell HIV-1 infection. From this study, we suggest that cell-to-cell infection may explain the high copy numbers of proviruses found in infected cells in vivo and may provide a mechanism through which HIV preserves sequence heterogeneity in viral quasispecies through genetic complementation.

  17. GADD45 proteins inhibit HIV-1 replication through specific suppression of HIV-1 transcription.

    PubMed

    Liang, Zhibin; Liu, Ruikang; Zhang, Hui; Zhang, Suzhen; Hu, Xiaomei; Tan, Juan; Liang, Chen; Qiao, Wentao

    2016-06-01

    GADD45 proteins are a group of stress-induced proteins and participate in various cellular pathways including cell cycle regulation, cell survival and death, DNA repair and demethylation. It was recently shown that HIV-1 infection induces the expression of GADD45 proteins. However, the effect of GADD45 on HIV-1 replication has not been studied. Here, we report that overexpression of GADD45 proteins reduces HIV-1 production through suppressing transcription from the HIV-1 LTR promoter. This inhibitory effect is specific to HIV-1, since GADD45 proteins neither inhibit the LTR promoters from other retroviruses nor reduce the production of these viruses. Knockdown of endogenous GADD45 modestly activates HIV-1 in the J-Lat A72 latency cell line, which suggests GADD45 proteins might play a role in maintaining HIV-1 latency.

  18. The Presence and Anti-HIV-1 Function of Tenascin C in Breast Milk and Genital Fluids.

    PubMed

    Mansour, Robin G; Stamper, Lisa; Jaeger, Frederick; McGuire, Erin; Fouda, Genevieve; Amos, Joshua; Barbas, Kimberly; Ohashi, Tomoo; Alam, S Munir; Erickson, Harold; Permar, Sallie R

    2016-01-01

    Tenascin-C (TNC) is a newly identified innate HIV-1-neutralizing protein present in breast milk, yet its presence and potential HIV-inhibitory function in other mucosal fluids is unknown. In this study, we identified TNC as a component of semen and cervical fluid of HIV-1-infected and uninfected individuals, although it is present at a significantly lower concentration and frequency compared to that of colostrum and mature breast milk, potentially due to genital fluid protease degradation. However, TNC was able to neutralize HIV-1 after exposure to low pH, suggesting that TNC could be active at low pH in the vaginal compartment. As mucosal fluids are complex and contain a number of proteins known to interact with the HIV-1 envelope, we further studied the relationship between the concentration of TNC and neutralizing activity in breast milk. The amount of TNC correlated only weakly with the overall innate HIV-1-neutralizing activity of breast milk of uninfected women and negatively correlated with neutralizing activity in milk of HIV-1 infected women, indicating that the amount of TNC in mucosal fluids is not adequate to impede HIV-1 transmission. Moreover, the presence of polyclonal IgG from milk of HIV-1 infected women, but not other HIV-1 envelope-binding milk proteins or monoclonal antibodies, blocked the neutralizing activity of TNC. Finally, as exogenous administration of TNC would be necessary for it to mediate measurable HIV-1 neutralizing activity in mucosal compartments, we established that recombinantly produced TNC has neutralizing activity against transmitted/founder HIV-1 strains that mimic that of purified TNC. Thus, we conclude that endogenous TNC concentration in mucosal fluids is likely inadequate to block HIV-1 transmission to uninfected individuals.

  19. Accuracy of the TRUGENE HIV-1 Genotyping Kit

    PubMed Central

    Grant, Robert M.; Kuritzkes, Daniel R.; Johnson, Victoria A.; Mellors, John W.; Sullivan, John L.; Swanstrom, Ronald; D'Aquila, Richard T.; Van Gorder, Mark; Holodniy, Mark; Lloyd, Jr., Robert M.; Reid, Caroline; Morgan, Gillian F.; Winslow, Dean L.

    2003-01-01

    Drug resistance and poor virological responses are associated with well-characterized mutations in the viral reading frames that encode the proteins that are targeted by currently available antiretroviral drugs. An integrated system was developed that includes target gene amplification, DNA sequencing chemistry (TRUGENE HIV-1 Genotyping Kit), and hardware and interpretative software (the OpenGene DNA Sequencing System) for detection of mutations in the human immunodeficiency virus type 1 (HIV-1) protease and reverse transcriptase sequences. The integrated system incorporates reverse transcription-PCR from extracted HIV-1 RNA, a coupled amplification and sequencing step (CLIP), polyacrylamide gel electrophoresis, semiautomated analysis of data, and generation of an interpretative report. To assess the accuracy and robustness of the assay system, 270 coded plasma specimens derived from nine patients were sent to six laboratories for blinded analysis. All specimens contained HIV-1 subtype B viruses. Results of 270 independent assays were compared to “gold standard” consensus sequences of the virus populations determined by sequence analysis of 16 to 20 clones of viral DNA amplicons derived from two independent PCRs using primers not used in the kit. The accuracy of the integrated system for nucleotide base identification was 98.7%, and the accuracy for codon identification at 54 sites associated with drug resistance was 97.6%. In a separate analysis of plasma spiked with infectious molecular clones, the assay reproducibly detected all 72 different drug resistance mutations that were evaluated. There were no significant differences in accuracy between laboratories, between technologists, between kit lots, or between days. This integrated assay system for the detection of HIV-1 drug resistance mutations has a high degree of accuracy and reproducibility in several laboratories. PMID:12682149

  20. Detection of Acute HIV-1 Infection by RT-LAMP.

    PubMed

    Rudolph, Donna L; Sullivan, Vickie; Owen, S Michele; Curtis, Kelly A

    2015-01-01

    A rapid, cost-effective diagnostic test for the detection of acute HIV-1 infection is highly desired. Isothermal amplification techniques, such as reverse-transcription loop-mediated isothermal amplification (RT-LAMP), exhibit characteristics that are ideal for the development of a rapid nucleic acid amplification test (NAAT) because they are quick, easy to perform and do not require complex, dedicated equipment and laboratory space. In this study, we assessed the ability of the HIV-1 RT-LAMP assay to detect acute HIV infection as compared to a representative rapid antibody test and several FDA-approved laboratory-based assays. The HIV-1 RT-LAMP assay detected seroconverting individuals one to three weeks earlier than a rapid HIV antibody test and up to two weeks earlier than a lab-based antigen/antibody (Ag/Ab) combo enzyme immunoassay (EIA). RT-LAMP was not as sensitive as a lab-based qualitative RNA assay, which could be attributed to the significantly smaller nucleic acid input volume. To our knowledge, this is the first demonstration of detecting acute HIV infection using the RT-LAMP assay. The availability of a rapid NAAT, such as the HIV-1 RT-LAMP assay, at the point of care (POC) or in laboratories that do not have access to large platform NAAT could increase the percentage of individuals who receive an acute HIV infection status or confirmation of their HIV status, while immediately linking them to counseling and medical care. In addition, early knowledge of HIV status could lead to reduced high-risk behavior at a time when individuals are at a higher risk for transmitting the virus. PMID:25993381

  1. Blocking HIV-1 transmission in the female reproductive tract: from microbicide development to exploring local antiviral responses

    PubMed Central

    Eid, Sahar G; Mangan, Niamh E; Hertzog, Paul J; Mak, Johnson

    2015-01-01

    The majority of new HIV-1 infections are transmitted sexually by penetrating the mucosal barrier to infect target cells. The development of microbicides to restrain heterosexual HIV-1 transmission in the past two decades has proven to be a challenging endeavor. Therefore, better understanding of the tissue environment in the female reproductive tract may assist in the development of the next generation of microbicides to prevent HIV-1 transmission. In this review, we highlight the important factors involved in the heterosexual transmission of HIV-1, provide an update on microbicides' clinical trials, and discuss how different delivery platforms and local immunity may empower the development of next generation of microbicide to block HIV-1 transmission in the female reproductive tract. PMID:26682051

  2. Citron kinase enhances ubiquitination of HIV-1 Gag protein and intracellular HIV-1 budding.

    PubMed

    Ding, Jiwei; Zhao, Jianyuan; Sun, Lei; Mi, Zeyun; Cen, Shan

    2016-09-01

    Assembly and budding of human immunodeficiency virus type 1 (HIV-1) particles is a complex process involving a number of host proteins. We have previously reported that the RhoA effector citron kinase enhances HIV-1 production. However, the underlying mechanism is not clear. In this study, we found that citron kinase interacted with HIV-1 Gag protein via its zinc finger and leucine zipper domains. Electron microscopy analysis revealed that citron kinase induced viral particle assembly in multivesicular bodies (MVBs). Citron kinase enhanced ubiquitination of HIV-1 Gag protein. Knockdown of Nedd4L, a member of the HECT ubiquitin E3 ligase family, partly decreased the ability of citron kinase to enhance HIV-1 production and reduced ubiquitination of HIV-1 Gag. Interestingly, the function of citron kinase to promote HIV-1 budding was severely impaired when endogenous ALIX was knocked down. Overexpression of the AAA-type ATPase VPS4 eliminated citron-kinase-mediated enhancement of HIV-1 production. Our results suggest that citron kinase interacts with HIV-1 Gag and enhances HIV-1 production by promoting Gag ubiquitination and inducing viral release via the MVB pathway. PMID:27339686

  3. Population-Level Immune-Mediated Adaptation in HIV-1 Polymerase during the North American Epidemic

    PubMed Central

    Kinloch, Natalie N.; MacMillan, Daniel R.; Le, Anh Q.; Cotton, Laura A.; Bangsberg, David R.; Buchbinder, Susan; Carrington, Mary; Fuchs, Jonathan; Harrigan, P. Richard; Koblin, Beryl; Kushel, Margot; Markowitz, Martin; Mayer, Kenneth; Milloy, M. J.; Schechter, Martin T.; Wagner, Theresa; Walker, Bruce D.; Carlson, Jonathan M.; Poon, Art F. Y.

    2015-01-01

    accumulate in circulation over time, potentially undermining host antiviral immunity to the transmitted viral strain. We studied >600 experimentally collected HIV-1 polymerase sequences linked to host HLA information dating back to 1979, along with phylogenetically reconstructed HIV-1 sequences dating back to the virus' introduction into North America. Overall, our results support the gradual spread of many—though not all—HIV-1 polymerase immune escape mutations in circulation over time. This is consistent with recent observations from other global regions, though the extent of polymorphism accumulation in North America appears to be lower than in populations with high seroprevalence, older epidemics, and/or limited HLA diversity. Importantly, the risk of acquiring an HIV-1 polymerase sequence at transmission that is substantially preadapted to one's HLA profile remains relatively low in North America, even in the present era. PMID:26559841

  4. HIV-1 RNA quantification in CRF02_AG HIV-1 infection: too easy to make mistakes.

    PubMed

    Tatarelli, Paola; Taramasso, Lucia; Di Biagio, Antonio; Sticchi, Laura; Nigro, Nicola; Barresi, Renata; Viscoli, Claudio; Bruzzone, Bianca

    2016-04-01

    The number of patients newly infected by HIV-1 non-B subtypes and circulating recombinant forms (CRFs) is increasing worldwide, including in the western countries. We report on a primary HIV-1 infection in a Caucasian patient. A routine quantitative assay (Nuclisens EasyQ HIV-1 2.0, BioMérieux SA) showed 6,700 HIV-1 RNA copies/ml. A combined antiretroviral therapy (cART) consistent with low baseline HIV-1 RNA was started. Few days later, the analysis performed with REGA HIV-1 Subtyping Tool - Version 3.0 attributed the HIV-1 sequence to the CRF02_AG recombinant form. Therefore, a second real-time PCR assay was performed, using the Versant HIV-1 RNA 1.0 Assay (kPCR) (Siemens HealthCare Diagnostics) which revealed a HIV-1 RNA of 230,000 copies/ml. Consequently, the ongoing cART was potentiated. This case suggests that the wide genetic variability of HIV-1 subtypes may affect the capability of the commonly used assays to detect and accurately quantify HIV-1 RNA in non-B subtypes and CRFs. In presence of CRFs different commercial HIV-1 RNA tests should be performed to find the most reliable for viral load quantification at the diagnosis, because it influences the choice of cART, and during the follow-up. Indeed, international guidelines for HIV-1 infection management suggest to monitor patient' HIV-RNA with the same assay over the course of treatment. As different commercial tests can be performed in the same laboratory with considerable difficulty, the laboratory should select an assay that is suitable not only for the more prevalent strain, but also for less frequent ones that, nevertheless, can occur. Then, knowing and investigating the spread of non-B strains has essential clinical and laboratory implications. PMID:27196556

  5. Two subtypes of HIV-1 among injection-drug users in southern China.

    PubMed

    Yu, X F; Chen, J; Shao, Y; Beyrer, C; Lai, S

    1998-04-25

    The rate of HIV-1 infection has increased steadily in China by about 80% annually and by the end of September 1997, 8277 HIV-1 cases had been reported, of whom more than 75% were IV drug users (IVDUs). UNAIDS, however, has estimated that up to 200,000 people could actually be infected with HIV-1 in China. Guangxi Province borders Yunnan province in the west and Vietnam to the south, and is a major transit area for heroin trafficking from the opium-growing region of Laos and Myanmar. Phylogenetic analyses of HIV-1 env sequences (C2-V3) obtained from 14 IVDUs found that 9 subjects from Pingxiang City were infected with subtype E and 5 from Baise City with subtype C. The 9 subtype E and 5 subtype C HIV-1 sequences were clustered together within each group, with significant bootstrap values of 100% and 95%, respectively. The subtype E sequences were more closely related to HIV-1 subtype E from Thailand than to those from Africa, and the subtype C sequences were clustered more closely to those from India than to those from Africa. Study results suggest 2 epidemiologically unrelated epidemics and 2 different sources; subtype C probably transmitted from Yunnan to Baise City through drug trafficking and IVDU interaction, and subtype E coming into China from Vietnam. PMID:9643749

  6. Memory CD4(+) T cells are the earliest detectable human immunodeficiency virus type 1 (HIV-1)-infected cells in the female genital mucosal tissue during HIV-1 transmission in an organ culture system.

    PubMed

    Gupta, Phalguni; Collins, Kelly B; Ratner, Deena; Watkins, Simon; Naus, Gregory J; Landers, Daniel V; Patterson, Bruce K

    2002-10-01

    The virologic and cellular factors that are involved in transmission of human immunodeficiency virus type 1 (HIV-1) across the female genital tissue are poorly understood. We have recently developed a human cervical tissue-derived organ culture model to study heterosexual transmission of HIV-1 that mimics the in vivo situation. Using this model we investigated the role of phenotypic characteristics of HIV-1 and identified the cell types that are first infected during transmission. Our data indicate that the cell-free R5 HIV-1 was more efficiently transmitted than cell-free X4 HIV-1. Cell-free and cell-associated HIV-1 had comparable transmission efficiency regardless of whether the virus was of R5 or X4 type. We have demonstrated that memory CD4(+) T cells and not Langerhans cells were the first HIV-1 RNA-positive cells detected at the epithelial-submucosal junction 6 h after virus exposure. Multicolor laser confocal microscopy demonstrated a globular distribution of HIV-1 gag-pol mRNA in the cytoplasm, and the distribution of CD4 and the CD45RO isoform was irregular on the cellular membrane. At 96 h postinoculation, in addition to memory CD4(+) T cells, HIV-1 RNA-positive Langerhans cells and macrophages were also detected. The identification of CD4(+) T cells in the tissue at 6 h was confirmed by flow cytometric simultaneous immunophenotyping and ultrasensitive fluorescence in situ hybridization assay on immune cells isolated from disaggregated tissue. Furthermore, PMPA [9-[2-(phosphonomethoxy)propyl] adenine], an antiretroviral compound, and UC781, a microbicide, inhibited HIV-1 transmission across the mucosa, indicating the utility of the organ culture to screen topical microbicides for their ability to block sexual transmission of HIV-1.

  7. Relationship between Functional Profile of HIV-1 Specific CD8 T Cells and Epitope Variability with the Selection of Escape Mutants in Acute HIV-1 Infection

    PubMed Central

    Goonetilleke, Nilu; Liu, Michael K. P.; Turnbull, Emma L.; Salazar-Gonzalez, Jesus F.; Hawkins, Natalie; Self, Steve; Watson, Sydeaka; Betts, Michael R.; Gay, Cynthia; McGhee, Kara; Pellegrino, Pierre; Williams, Ian; Tomaras, Georgia D.; Haynes, Barton F.; Gray, Clive M.; Borrow, Persephone; Roederer, Mario; McMichael, Andrew J.; Weinhold, Kent J.

    2011-01-01

    In the present study, we analyzed the functional profile of CD8+ T-cell responses directed against autologous transmitted/founder HIV-1 isolates during acute and early infection, and examined whether multifunctionality is required for selection of virus escape mutations. Seven anti-retroviral therapy-naïve subjects were studied in detail between 1 and 87 weeks following onset of symptoms of acute HIV-1 infection. Synthetic peptides representing the autologous transmitted/founder HIV-1 sequences were used in multiparameter flow cytometry assays to determine the functionality of HIV-1-specific CD8+ T memory cells. In all seven patients, the earliest T cell responses were predominantly oligofunctional, although the relative contribution of multifunctional cell responses increased significantly with time from infection. Interestingly, only the magnitude of the total and not of the poly-functional T-cell responses was significantly associated with the selection of escape mutants. However, the high contribution of MIP-1β-producing CD8+ T-cells to the total response suggests that mechanisms not limited to cytotoxicity could be exerting immune pressure during acute infection. Lastly, we show that epitope entropy, reflecting the capacity of the epitope to tolerate mutational change and defined as the diversity of epitope sequences at the population level, was also correlated with rate of emergence of escape mutants. PMID:21347345

  8. Substance abuse, HIV-1 and hepatitis

    PubMed Central

    Parikh, Nirzari; Nonnemacher, Michael R.; Pirrone, Vanessa; Block, Timothy; Mehta, Anand; Wigdahl, Brian

    2013-01-01

    During the course of human immunodeficiency virus type 1 (HIV-1) disease, the virus has been shown to effectively escape the immune response with the subsequent establishment of latent viral reservoirs in specific cell populations within the peripheral blood (PB) and associated lymphoid tissues, bone marrow (BM), brain, and potentially other end organs. HIV-1, along with hepatitis B and C viruses (HBV and HCV), are known to share similar routes of transmission, including intravenous drug use, blood transfusions, sexual intercourse, and perinatal exposure. Substance abuse, including the use of opioids and cocaine, is a significant risk factor for exposure to HIV-1 and the development of acquired immune deficiency syndrome, as well as HBV and HCV exposure, infection, and disease. Thus, coinfection with HIV-1 and HBV or HCV is common and may be impacted by chronic substance abuse during the course of disease. HIV-1 impacts the natural course of HBV and HCV infection by accelerating the progression of HBV/HCV-associated liver disease toward end-stage cirrhosis and quantitative depletion of the CD4+ T-cell compartment. HBV or HCV coinfection with HIV-1 is also associated with increased mortality when compared to either infection alone. This review focuses on the impact of substance abuse and coinfection with HBV and HCV in the PB, BM, and brain on the HIV-1 pathogenic process as it relates to viral pathogenesis, disease progression, and the associated immune response during the course of this complex interplay. The impact of HIV-1 and substance abuse on hepatitis virus-induced disease is also a focal point. PMID:22973853

  9. Tenascin-C is an innate broad-spectrum, HIV-1–neutralizing protein in breast milk

    PubMed Central

    Fouda, Genevieve G.; Jaeger, Frederick H.; Amos, Joshua D.; Ho, Carrie; Kunz, Erika L.; Anasti, Kara; Stamper, Lisa W.; Liebl, Brooke E.; Barbas, Kimberly H.; Ohashi, Tomoo; Moseley, Martin Arthur; Liao, Hua-Xin; Erickson, Harold P.; Alam, S. Munir; Permar, Sallie R.

    2013-01-01

    Achieving an AIDS-free generation will require elimination of postnatal transmission of HIV-1 while maintaining the nutritional and immunologic benefits of breastfeeding for infants in developing regions. Maternal/infant antiretroviral prophylaxis can reduce postnatal HIV-1 transmission, yet toxicities and the development of drug-resistant viral strains may limit the effectiveness of this strategy. Interestingly, in the absence of antiretroviral prophylaxis, greater than 90% of infants exposed to HIV-1 via breastfeeding remain uninfected, despite daily mucosal exposure to the virus for up to 2 y. Moreover, milk of uninfected women inherently neutralizes HIV-1 and prevents virus transmission in animal models, yet the factor(s) responsible for this anti-HIV activity is not well-defined. In this report, we identify a primary HIV-1–neutralizing protein in breast milk, Tenascin-C (TNC). TNC is an extracellular matrix protein important in fetal development and wound healing, yet its antimicrobial properties have not previously been established. Purified TNC captured and neutralized multiclade chronic and transmitted/founder HIV-1 variants, and depletion of TNC abolished the HIV-1–neutralizing activity of milk. TNC bound the HIV-1 Envelope protein at a site that is induced upon engagement of its primary receptor, CD4, and is blocked by V3 loop- (19B and F39F) and chemokine coreceptor binding site-directed (17B) monoclonal antibodies. Our results demonstrate the ability of an innate mucosal host protein found in milk to neutralize HIV-1 via binding to the chemokine coreceptor site, potentially explaining why the majority of HIV-1–exposed breastfed infants are protected against mucosal HIV-1 transmission. PMID:24145401

  10. HIV-1 proteins, Tat and gp120, target the developing dopamine system.

    PubMed

    Fitting, Sylvia; Booze, Rosemarie M; Mactutus, Charles F

    2015-01-01

    In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection. PMID:25613135

  11. HIV-1 Proteins, Tat and gp120, Target the Developing Dopamine System

    PubMed Central

    Fitting, Sylvia; Booze, Rosemarie M.; Mactutus, Charles F.

    2015-01-01

    In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection. PMID:25613135

  12. Protease inhibitors effectively block cell-to-cell spread of HIV-1 between T cells

    PubMed Central

    2013-01-01

    Background The Human Immunodeficiency Virus type-1 (HIV-1) spreads by cell-free diffusion and by direct cell-to-cell transfer, the latter being a significantly more efficient mode of transmission. Recently it has been suggested that cell-to-cell spread may permit ongoing virus replication in the presence of antiretroviral therapy (ART) based on studies performed using Reverse Transcriptase Inhibitors (RTIs). Protease Inhibitors (PIs) constitute an important component of ART; however whether this class of inhibitors can suppress cell-to-cell transfer of HIV-1 is unexplored. Here we have evaluated the inhibitory effect of PIs during cell-to-cell spread of HIV-1 between T lymphocytes. Results Using quantitative assays in cell line and primary cell systems that directly measure the early steps of HIV-1 infection we find that the PIs Lopinavir and Darunavir are equally potent against both cell-free and cell-to-cell spread of HIV-1. We further show that a protease resistant mutant maintains its resistant phenotype during cell-to-cell spread and is transmitted more efficiently than wild-type virus in the presence of drug. By contrast we find that T cell-T cell spread of HIV-1 is 4–20 fold more resistant to inhibition by the RTIs Nevirapine, Zidovudine and Tenofovir. Notably, varying the ratio of infected and uninfected cells in co-culture impacted on the degree of inhibition, indicating that the relative efficacy of ART is dependent on the multiplicity of infection. Conclusions We conclude that if the variable effects of antiviral drugs on cell-to-cell virus dissemination of HIV-1 do indeed impact on viral replication and maintenance of viral reservoirs this is likely to be influenced by the antiviral drug class, since PIs appear particularly effective against both modes of HIV-1 spread. PMID:24364896

  13. Combination genetic therapy to inhibit HIV-1.

    PubMed

    Strayer, David S; Branco, Francisco; Landré, Julien; BouHamdan, Mohamad; Shaheen, Farida; Pomerantz, Roger J

    2002-01-01

    Compared with single agents, combination antilentiviral pharmacotherapy targets multiple HIV-1 functions simultaneously, maximizing efficacy and decreasing chances of escape mutations. Combination genetic therapy could theoretically enhance efficacy similarly, but delivery of even single genes to high percentages of hematopoietic cells or their derivatives has proven problematic. Because of their high efficiency of gene delivery, we tested recombinant SV40-derived vectors (rSV40s) for this purpose. We made six rSV40s, each carrying a different transgene that targeted a different lentiviral function. We tested the ability of these constructs, individually and in double and triple combinations, to protect SupT1 human T lymphoma cells from HIV-1 challenge. Single chain antibodies (SFv) against CXCR4 and against HIV-1 reverse transcriptase (RT) and integrase (IN) were used, as were polymeric TAR decoys (PolyTAR) and a dominant-negative mutant of HIV-1 Rev (RevM10). Immunostaining showed that virtually all doubly treated cells expressed both transgenes. All transgenes individually protected from HIV-1 but, except for anti-CXCR4 SFv, their effectiveness diminished as challenge doses increased from 40 through 2500 tissue culture infectious dose(50) (TCID(50))/10(6) cells. However, all combinations of transgenes protected target cells better than individual transgenes, even from the highest challenge doses. Thus, combination gene therapies may inhibit HIV-1 better than single agents, and rSV40s may facilitate delivery of multigene therapeutics.

  14. Exosomes: Implications in HIV-1 Pathogenesis

    PubMed Central

    Madison, Marisa N.; Okeoma, Chioma M.

    2015-01-01

    Exosomes are membranous nanovesicles of endocytic origin that carry host and pathogen derived genomic, proteomic, and lipid cargos. Exosomes are secreted by most cell types into the extracellular milieu and are subsequently internalized by recipient cells. Upon internalization, exosomes condition recipient cells by donating their cargos and/or activating various signal transduction pathways, consequently regulating physiological and pathophysiological processes. The role of exosomes in viral pathogenesis, especially human immunodeficiency virus type 1 [HIV-1] is beginning to unravel. Recent research reports suggest that exosomes from various sources play important but different roles in the pathogenesis of HIV-1. From these reports, it appears that the source of exosomes is the defining factor for the exosomal effect on HIV-1. In this review, we will describe how HIV-1 infection is modulated by exosomes and in turn how exosomes are targeted by HIV-1 factors. Finally, we will discuss potentially emerging therapeutic options based on exosomal cargos that may have promise in preventing HIV-1 transmission. PMID:26205405

  15. Exosomes: Implications in HIV-1 Pathogenesis.

    PubMed

    Madison, Marisa N; Okeoma, Chioma M

    2015-07-20

    Exosomes are membranous nanovesicles of endocytic origin that carry host and pathogen derived genomic, proteomic, and lipid cargos. Exosomes are secreted by most cell types into the extracellular milieu and are subsequently internalized by recipient cells. Upon internalization, exosomes condition recipient cells by donating their cargos and/or activating various signal transduction pathways, consequently regulating physiological and pathophysiological processes. The role of exosomes in viral pathogenesis, especially human immunodeficiency virus type 1 [HIV-1] is beginning to unravel. Recent research reports suggest that exosomes from various sources play important but different roles in the pathogenesis of HIV-1. From these reports, it appears that the source of exosomes is the defining factor for the exosomal effect on HIV-1. In this review, we will describe how HIV-1 infection is modulated by exosomes and in turn how exosomes are targeted by HIV-1 factors. Finally, we will discuss potentially emerging therapeutic options based on exosomal cargos that may have promise in preventing HIV-1 transmission.

  16. Envelope gene evolution and HIV-1 neuropathogenesis

    PubMed Central

    Vázquez-Santiago, Fabián J.; Rivera-Amill, Vanessa

    2016-01-01

    In the era of combined antiretroviral therapy (cART), HIV-associated neurocognitive disorders (HAND) account for 40 to 56% of all HIV+ cases. During the acute stage of HIV-1 infection (<6 months), the virus invades and replicates within the central nervous system (CNS). Compared to peripheral tissues, the local CNS cell population expresses distinct levels of chemokine receptors, which levels exert selective pressure on the invading virus. HIV-1 envelope (env) sequences recovered from the brains and cerebrospinal fluid (CSF) of neurocognitively impaired HIV+ subjects often display higher nucleotide variability as compared to non-impaired HIV+ subjects. Specifically, env evolution provides HIV-1 with the strategies to evade host immune response, to reduce chemokine receptor dependence, to increase co-receptor binding efficiency, and to potentiate neurotoxicity. The evolution of env within the CNS leads to changes that may result in the emergence of novel isolates with neurotoxic and neurovirulent features. However, whether specific factors of HIV-1 evolution lead to the emergence of neurovirulent and neurotropic isolates remains ill-defined. HIV-1 env evolution is an ongoing phenomenon that occurs independently of neurological and neurocognitive disease severity; thus HIV env evolution may play a pivotal and reciprocal role in the etiology of HAND. Despite the use of cART, the reactivation of latent viral reservoirs represents a clinical challenge because of the replenishment of the viral pool that may subsequently lead to persistent infection. Therefore, gaining a more complete understanding of how HIV-1 env evolves over the course of the disease should be considered for the development of future therapies aimed at controlling CNS burden, diminishing persistent viremia, and eradicating viral reservoirs. Here we review the current literature on the role of HIV-1 env evolution in the setting of HAND disease progression and on the impact of cART on the dynamics of

  17. N6-methyladenosine of HIV-1 RNA regulates viral infection and HIV-1 Gag protein expression

    PubMed Central

    Tirumuru, Nagaraja; Zhao, Boxuan Simen; Lu, Wuxun; Lu, Zhike; He, Chuan; Wu, Li

    2016-01-01

    The internal N6-methyladenosine (m6A) methylation of eukaryotic nuclear RNA controls post-transcriptional gene expression, which is regulated by methyltransferases (writers), demethylases (erasers), and m6A-binding proteins (readers) in cells. The YTH domain family proteins (YTHDF1–3) bind to m6A-modified cellular RNAs and affect RNA metabolism and processing. Here, we show that YTHDF1–3 proteins recognize m6A-modified HIV-1 RNA and inhibit HIV-1 infection in cell lines and primary CD4+ T-cells. We further mapped the YTHDF1–3 binding sites in HIV-1 RNA from infected cells. We found that the overexpression of YTHDF proteins in cells inhibited HIV-1 infection mainly by decreasing HIV-1 reverse transcription, while knockdown of YTHDF1–3 in cells had the opposite effects. Moreover, silencing the m6A writers decreased HIV-1 Gag protein expression in virus-producing cells, while silencing the m6A erasers increased Gag expression. Our findings suggest an important role of m6A modification of HIV-1 RNA in viral infection and HIV-1 protein synthesis. DOI: http://dx.doi.org/10.7554/eLife.15528.001 PMID:27371828

  18. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules

    PubMed Central

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S. Y.

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This “shock” approach is then followed by “kill” of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells. PMID:27049645

  19. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules.

    PubMed

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This "shock" approach is then followed by "kill" of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells.

  20. N(6)-methyladenosine of HIV-1 RNA regulates viral infection and HIV-1 Gag protein expression.

    PubMed

    Tirumuru, Nagaraja; Zhao, Boxuan Simen; Lu, Wuxun; Lu, Zhike; He, Chuan; Wu, Li

    2016-01-01

    The internal N(6)-methyladenosine (m(6)A) methylation of eukaryotic nuclear RNA controls post-transcriptional gene expression, which is regulated by methyltransferases (writers), demethylases (erasers), and m(6)A-binding proteins (readers) in cells. The YTH domain family proteins (YTHDF1-3) bind to m(6)A-modified cellular RNAs and affect RNA metabolism and processing. Here, we show that YTHDF1-3 proteins recognize m(6)A-modified HIV-1 RNA and inhibit HIV-1 infection in cell lines and primary CD4(+) T-cells. We further mapped the YTHDF1-3 binding sites in HIV-1 RNA from infected cells. We found that the overexpression of YTHDF proteins in cells inhibited HIV-1 infection mainly by decreasing HIV-1 reverse transcription, while knockdown of YTHDF1-3 in cells had the opposite effects. Moreover, silencing the m(6)A writers decreased HIV-1 Gag protein expression in virus-producing cells, while silencing the m(6)A erasers increased Gag expression. Our findings suggest an important role of m(6)A modification of HIV-1 RNA in viral infection and HIV-1 protein synthesis. PMID:27371828

  1. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules.

    PubMed

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This "shock" approach is then followed by "kill" of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells. PMID:27049645

  2. Herpes simplex virus type-2 stimulates HIV-1 replication in cervical tissues: implications for HIV-1 transmission and efficacy of anti-HIV-1 microbicides.

    PubMed

    Rollenhagen, C; Lathrop, M J; Macura, S L; Doncel, G F; Asin, S N

    2014-09-01

    Herpes Simplex virus Type-2 (HSV-2) increases the risk of HIV-1 acquisition, yet the mechanism for this viral pathogen to regulate the susceptibility of the cervicovaginal mucosa to HIV-1 is virtually unknown. Using ex vivo human ectocervical tissue models, we report greater levels of HIV-1 reverse transcription, DNA integration, RNA expression, and virions release in HIV-1/HSV-2 co-infected tissues compared with HIV-1 only infected tissues (P<0.05). Enhanced HIV-1 replication was associated with increased CD4, CCR5, and CD38 transcription (P<0.05) and increased number of CD4(+)/CCR5(+)/CD38(+) T cells in HIV-1/HSV-2 co-infected tissues compared with tissues infected with HIV-1 alone. Tenofovir (TFV) 1% gel, the leading microbicide candidate, demonstrated only partial protection against HIV-1, when applied vaginally before and after sexual intercourse. It is possible that mucosal inflammation, in particular that induced by HSV-2 infection, may have decreased TFV efficacy. HSV-2 upregulated the number of HIV-1-infected cells and elevated the concentration of TFV needed to decrease HIV-1 infection. Similarly, only high concentrations of TFV inhibited HSV-2 replication in HIV-1/HSV-2-infected tissues. Thus, HSV-2 co-infection and mucosal immune cell activation should be taken into consideration when designing preventative strategies for sexual transmission of HIV-1.

  3. Structured Observations Reveal Slow HIV-1 CTL Escape

    PubMed Central

    Roberts, Hannah E.; Hurst, Jacob; Robinson, Nicola; Brown, Helen; Flanagan, Peter; Vass, Laura; Fidler, Sarah; Weber, Jonathan; Babiker, Abdel; Phillips, Rodney E.; McLean, Angela R.; Frater, John

    2015-01-01

    The existence of viral variants that escape from the selection pressures imposed by cytotoxic T-lymphocytes (CTLs) in HIV-1 infection is well documented, but it is unclear when they arise, with reported measures of the time to escape in individuals ranging from days to years. A study of participants enrolled in the SPARTAC (Short Pulse Anti-Retroviral Therapy at HIV Seroconversion) clinical trial allowed direct observation of the evolution of CTL escape variants in 125 adults with primary HIV-1 infection observed for up to three years. Patient HLA-type, longitudinal CD8+ T-cell responses measured by IFN-γ ELISpot and longitudinal HIV-1 gag, pol, and nef sequence data were used to study the timing and prevalence of CTL escape in the participants whilst untreated. Results showed that sequence variation within CTL epitopes at the first time point (within six months of the estimated date of seroconversion) was consistent with most mutations being transmitted in the infecting viral strain rather than with escape arising within the first few weeks of infection. Escape arose throughout the first three years of infection, but slowly and steadily. Approximately one third of patients did not drive any new escape in an HLA-restricted epitope in just under two years. Patients driving several escape mutations during these two years were rare and the median and modal numbers of new escape events in each patient were one and zero respectively. Survival analysis of time to escape found that possession of a protective HLA type significantly reduced time to first escape in a patient (p = 0.01), and epitopes escaped faster in the face of a measurable CD8+ ELISpot response (p = 0.001). However, even in an HLA matched host who mounted a measurable, specific, CD8+ response the average time before the targeted epitope evolved an escape mutation was longer than two years. PMID:25642847

  4. Structured observations reveal slow HIV-1 CTL escape.

    PubMed

    Roberts, Hannah E; Hurst, Jacob; Robinson, Nicola; Brown, Helen; Flanagan, Peter; Vass, Laura; Fidler, Sarah; Weber, Jonathan; Babiker, Abdel; Phillips, Rodney E; McLean, Angela R; Frater, John

    2015-02-01

    The existence of viral variants that escape from the selection pressures imposed by cytotoxic T-lymphocytes (CTLs) in HIV-1 infection is well documented, but it is unclear when they arise, with reported measures of the time to escape in individuals ranging from days to years. A study of participants enrolled in the SPARTAC (Short Pulse Anti-Retroviral Therapy at HIV Seroconversion) clinical trial allowed direct observation of the evolution of CTL escape variants in 125 adults with primary HIV-1 infection observed for up to three years. Patient HLA-type, longitudinal CD8+ T-cell responses measured by IFN-γ ELISpot and longitudinal HIV-1 gag, pol, and nef sequence data were used to study the timing and prevalence of CTL escape in the participants whilst untreated. Results showed that sequence variation within CTL epitopes at the first time point (within six months of the estimated date of seroconversion) was consistent with most mutations being transmitted in the infecting viral strain rather than with escape arising within the first few weeks of infection. Escape arose throughout the first three years of infection, but slowly and steadily. Approximately one third of patients did not drive any new escape in an HLA-restricted epitope in just under two years. Patients driving several escape mutations during these two years were rare and the median and modal numbers of new escape events in each patient were one and zero respectively. Survival analysis of time to escape found that possession of a protective HLA type significantly reduced time to first escape in a patient (p = 0.01), and epitopes escaped faster in the face of a measurable CD8+ ELISpot response (p = 0.001). However, even in an HLA matched host who mounted a measurable, specific, CD8+ response the average time before the targeted epitope evolved an escape mutation was longer than two years.

  5. HIV-1 Genetic Variability and Clinical Implications

    PubMed Central

    Santoro, Maria Mercedes; Perno, Carlo Federico

    2013-01-01

    Despite advances in antiretroviral therapy that have revolutionized HIV disease management, effective control of the HIV infection pandemic remains elusive. Beyond the classic non-B endemic areas, HIV-1 non-B subtype infections are sharply increasing in previous subtype B homogeneous areas such as Europe and North America. As already known, several studies have shown that, among non-B subtypes, subtypes C and D were found to be more aggressive in terms of disease progression. Luckily, the response to antiretrovirals against HIV-1 seems to be similar among different subtypes, but these results are mainly based on small or poorly designed studies. On the other hand, differences in rates of acquisition of resistance among non-B subtypes are already being observed. This different propensity, beyond the type of treatment regimens used, as well as access to viral load testing in non-B endemic areas seems to be due to HIV-1 clade specific peculiarities. Indeed, some non-B subtypes are proved to be more prone to develop resistance compared to B subtype. This phenomenon can be related to the presence of subtype-specific polymorphisms, different codon usage, and/or subtype-specific RNA templates. This review aims to provide a complete picture of HIV-1 genetic diversity and its implications for HIV-1 disease spread, effectiveness of therapies, and drug resistance development. PMID:23844315

  6. The hunt for HIV-1 integrase inhibitors.

    PubMed

    Lataillade, Max; Kozal, Michael J

    2006-07-01

    Currently, there are three distinct mechanistic classes of antiretrovirals: inhibitors of the HIV- 1 reverse transcriptase and protease enzymes and inhibitors of HIV entry, including receptor and coreceptor binding and cell fusion. A new drug class that inhibits the HIV-1 integrase enzyme (IN) is in development and may soon be available in the clinic. IN is an attractive drug target because it is essential for a stable and productive HIV-1 infection and there is no mammalian homologue of IN. Inhibitors of integrase enzyme (INI) block the integration of viral double-stranded DNA into the host cell's chromosomal DNA. HIV-1 integration has many potential steps that can be inhibited and several new compounds that target specific integration steps have been identified by drug developers. Recently, two INIs, GS-9137 and MK-0518, demonstrated promising early clinical trial results and have been advanced into later stage trials. In this review, we describe how IN facilitates HIV-1 integration, the needed enzyme cofactors, and the resultant byproducts created during integration. Furthermore, we review the different INIs under development, their mechanism of actions, site of IN inhibition, potency, resistance patterns, and discuss the early clinical trial results.

  7. Restriction Factors in HIV-1 Disease Progression.

    PubMed

    Merindol, Natacha; Berthoux, Lionel

    2015-01-01

    About 35 million people worldwide were living with HIV-1 at the end of 2013 and over 25 million have already died of AIDS. AIDS patients show high variability in the speed of disease progression in the absence of treatment. While certain immunological traits have been shown to correlate with accelerated or slowed progression in some subjects, including slow progressors, factors controlling HIV-1 replication and disease kinetics remain largely enigmatic. The importance of T lymphocytes and of protective HLA-alleles is undeniable, but not sufficient to explain every attenuated phenotype. A thorough understanding of HIV-1 infection control in these patient subsets may help the development of novel strategies for treatment and prevention. Restriction factors are type I interferon-induced specialized cellular proteins that block viruses at different steps of their life cycle. TRIM5α, Mx2/MxB, TRIM22/Staf50, SAMHD1, p21/CDKN1, tetherin/BST2/CD137, APOBEC3G and APOBEC3F have all been proposed to inhibit HIV-1, often with gene variant- or cellular context-specificity. Recent evidence highlights their possible implication in AIDS disease progression. In this review, we depict their restrictive activity against HIV-1 and recapitulate the latest data on their potential role in vivo, in both normal and slow progressors.

  8. HIV-1 DNA shedding in genital ulcers and its associated risk factors in Pune, India.

    PubMed

    Gadkari, D A; Quinn, T C; Gangakhedkar, R R; Mehendale, S M; Divekar, A D; Risbud, A R; Chan-Tack, K; Shepherd, M; Gaydos, C; Bollinger, R C

    1998-07-01

    HIV infection status was determined in 302 consecutive patients with genital ulcer disease (GUD) presenting to two sexually transmitted disease (STD) clinics in Pune, India. Of the 71 (24%) individuals with HIV infection, 67 (94%) were HIV antibody-positive, and 4 (6%) were HIV antibody-negative but p24 antigen-positive at the time of presentation. HIV-1 DNA was detected in 24 (34%) specimens. The genital ulcers of all four acutely infected p24-antigenemic subjects were HIV-1 DNA-positive by polymerase chain reaction (PCR) assay, compared with 20 of 67 (30%) seropositive patients (p = .01). Presence of chancroid, GUD symptoms for > 10 days, and concurrent diagnosis of cervicitis or urethritis were significantly associated risk factors for HIV-1 DNA shedding in ulcers. Early GUD diagnosis and aggressive treatment of HIV-infected patients may significantly reduce secondary transmission of HIV to other sex partners.

  9. Population genomics of intrapatient HIV-1 evolution.

    PubMed

    Zanini, Fabio; Brodin, Johanna; Thebo, Lina; Lanz, Christa; Bratt, Göran; Albert, Jan; Neher, Richard A

    2015-01-01

    Many microbial populations rapidly adapt to changing environments with multiple variants competing for survival. To quantify such complex evolutionary dynamics in vivo, time resolved and genome wide data including rare variants are essential. We performed whole-genome deep sequencing of HIV-1 populations in 9 untreated patients, with 6-12 longitudinal samples per patient spanning 5-8 years of infection. The data can be accessed and explored via an interactive web application. We show that patterns of minor diversity are reproducible between patients and mirror global HIV-1 diversity, suggesting a universal landscape of fitness costs that control diversity. Reversions towards the ancestral HIV-1 sequence are observed throughout infection and account for almost one third of all sequence changes. Reversion rates depend strongly on conservation. Frequent recombination limits linkage disequilibrium to about 100 bp in most of the genome, but strong hitch-hiking due to short range linkage limits diversity. PMID:26652000

  10. Assessment of mucosal immunity to HIV-1.

    PubMed

    Jespers, Vicky; Harandi, Ali M; Hinkula, Jorma; Medaglini, Donata; Le Grand, Roger; Stahl-Hennig, Christiane; Bogers, Willy; El Habib, Raphaelle; Wegmann, Frank; Fraser, Carol; Cranage, Martin; Shattock, Robin J; Spetz, Anna-Lena

    2010-04-01

    A key gap in the development and evaluation of HIV-1 vaccines is insufficient knowledge with regard to sampling techniques and assessment of mucosal immune responses required for early prevention and inhibition of viral dissemination. In an attempt to start bridging this gap, the EUROPRISE network of scientists working on HIV-1 vaccine and microbicide research organized a workshop with the aim to review the types of mucosal responses/biomarkers currently measured in mucosal immunology and to define how the mucosal responses/biomarkers are measured and/or the assays and sampling methods used. The Workshop addressed two critical questions: first whether, with current knowledge, it would be possible to define a consensus set of mucosal sampling methods to facilitate cross-species comparisons and ensure standardized implementation in clinical trials; second to determine the remaining challenges (technical and logistical) and their possible solutions for assessing mucosal responses to HIV-1 vaccines. PMID:20370549

  11. Population genomics of intrapatient HIV-1 evolution.

    PubMed

    Zanini, Fabio; Brodin, Johanna; Thebo, Lina; Lanz, Christa; Bratt, Göran; Albert, Jan; Neher, Richard A

    2015-01-01

    Many microbial populations rapidly adapt to changing environments with multiple variants competing for survival. To quantify such complex evolutionary dynamics in vivo, time resolved and genome wide data including rare variants are essential. We performed whole-genome deep sequencing of HIV-1 populations in 9 untreated patients, with 6-12 longitudinal samples per patient spanning 5-8 years of infection. The data can be accessed and explored via an interactive web application. We show that patterns of minor diversity are reproducible between patients and mirror global HIV-1 diversity, suggesting a universal landscape of fitness costs that control diversity. Reversions towards the ancestral HIV-1 sequence are observed throughout infection and account for almost one third of all sequence changes. Reversion rates depend strongly on conservation. Frequent recombination limits linkage disequilibrium to about 100 bp in most of the genome, but strong hitch-hiking due to short range linkage limits diversity.

  12. HIV-1 Neutralizing Antibodies with Limited Hypermutation from an Infant.

    PubMed

    Simonich, Cassandra A; Williams, Katherine L; Verkerke, Hans P; Williams, James A; Nduati, Ruth; Lee, Kelly K; Overbaugh, Julie

    2016-06-30

    HIV-1 broadly neutralizing antibodies (bnAbs) develop in a subset of infected adults and exhibit high levels of somatic hypermutation (SHM) due to years of affinity maturation. There is no precedent for eliciting highly mutated antibodies by vaccination, nor is it practical to wait years for a desired response. Infants develop broad responses early, which may suggest a more direct path to generating bnAbs. Here, we isolated ten neutralizing antibodies (nAbs) contributing to plasma breadth of an infant at ∼1 year post-infection, including one with cross-clade breadth. The nAbs bind to envelope trimer from the transmitted virus, suggesting that this interaction may have initiated development of the infant nAbs. The infant cross-clade bnAb targets the N332 supersite on envelope but, unlike adult bnAbs targeting this site, lacks indels and has low SHM. The identification of this infant bnAb illustrates that HIV-1-specific neutralization breadth can develop without prolonged affinity maturation and extensive SHM. PMID:27345369

  13. Assessing the HIV-1 Epidemic in Brazilian Drug Users: A Molecular Epidemiology Approach

    PubMed Central

    Guimarães, Monick Lindenmeyer; Marques, Bianca Cristina Leires; Bertoni, Neilane; Teixeira, Sylvia Lopes Maia; Morgado, Mariza Gonçalves; Bastos, Francisco Inácio

    2015-01-01

    Person who inject illicit substances have an important role in HIV-1 blood and sexual transmission and together with person who uses heavy non-injecting drugs may have less than optimal adherence to anti-retroviral treatment and eventually could transmit resistant HIV variants. Unfortunately, molecular biology data on such key population remain fragmentary in most low and middle-income countries. The aim of the present study was to assess HIV infection rates, evaluate HIV-1 genetic diversity, drug resistance, and to identify HIV transmission clusters in heavy drug users (DUs). For this purpose, DUs were recruited in the context of a Respondent-Driven Sampling (RDS) study in different Brazilian cities during 2009. Overall, 2,812 individuals were tested for HIV, and 168 (6%) of them were positive, of which 19 (11.3%) were classified as recent seroconverters, corresponding to an estimated incidence rate of 1.58%/year (95% CI 0.92–2.43%). Neighbor joining phylogenetic trees from env and pol regions and bootscan analyses were employed to subtype the virus from132 HIV-1-infected individuals. HIV-1 subtype B was prevalent in most of the cities under analysis, followed by BF recombinants (9%-35%). HIV-1 subtype C was the most prevalent in Curitiba (46%) and Itajaí (86%) and was also detected in Brasília (9%) and Campo Grande (20%). Pure HIV-1F infections were detected in Rio de Janeiro (9%), Recife (6%), Salvador (6%) and Brasília (9%). Clusters of HIV transmission were assessed by Maximum likelihood analyses and were cross-compared with the RDS network structure. Drug resistance mutations were verified in 12.2% of DUs. Our findings reinforce the importance of the permanent HIV-1 surveillance in distinct Brazilian cities due to viral resistance and increasing subtype heterogeneity all over Brazil, with relevant implications in terms of treatment monitoring, prophylaxis and vaccine development. PMID:26536040

  14. MAS NMR of HIV-1 protein assemblies

    NASA Astrophysics Data System (ADS)

    Suiter, Christopher L.; Quinn, Caitlin M.; Lu, Manman; Hou, Guangjin; Zhang, Huilan; Polenova, Tatyana

    2015-04-01

    The negative global impact of the AIDS pandemic is well known. In this perspective article, the utility of magic angle spinning (MAS) NMR spectroscopy to answer pressing questions related to the structure and dynamics of HIV-1 protein assemblies is examined. In recent years, MAS NMR has undergone major technological developments enabling studies of large viral assemblies. We discuss some of these evolving methods and technologies and provide a perspective on the current state of MAS NMR as applied to the investigations into structure and dynamics of HIV-1 assemblies of CA capsid protein and of Gag maturation intermediates.

  15. Novel vaccine vectors for HIV-1

    PubMed Central

    Picker, Louis J.

    2014-01-01

    The ultimate solution to the global HIV-1 epidemic will probably require the development of a safe and effective vaccine. Multiple vaccine platforms have been evaluated in both preclinical and clinical trials, but, given the disappointing results of the clinical efficacy studies so far, novel vaccine approaches are needed. In this Opinion article, we discuss the scientific basis and clinical potential of novel adenovirus and cytomegalovirus vaccine vectors for HIV-1 as two contrasting, but potentially complementary, vector approaches. Both of these vector platforms have demonstrated partial protection against stringent simian immunodeficiency virus challenges in rhesus monkeys using different immunological mechanisms. PMID:25296195

  16. HIV-1 Protease: Structure, Dynamics and Inhibition

    SciTech Connect

    Louis, John M.; Ishima, R.; Torchia, D.A.; Weber, Irene T.

    2008-06-03

    The HIV-1 protease is synthesized as part of a large Gag-Pol precursor protein. It is responsible for its own release from the precursor and the processing of the Gag and Gag-Pol polyproteins into the mature structural and functional proteins required for virus maturation. Because of its indispensable role, the mature HIV-1 protease dimer has proven to be a successful target for the development of antiviral agents. In the last 5 years, a major emphasis in protease research has been to improve inhibitor design and treatment regimens.

  17. Co-evolution of a broadly neutralizing HIV-1 antibody and founder virus

    PubMed Central

    Liao, Hua-Xin; Lynch, Rebecca; Zhou, Tongqing; Gao, Feng; Alam, S. Munir; Boyd, Scott D.; Fire, Andrew Z.; Roskin, Krishna M.; Schramm, Chaim A.; Zhang, Zhenhai; Zhu, Jiang; Shapiro, Lawrence; Mullikin, James C.; Gnanakaran, S.; Hraber, Peter; Wiehe, Kevin; Kelsoe, Garnett; Yang, Guang; Xia, Shi-Mao; Montefiori, David C.; Parks, Robert; Lloyd, Krissey E.; Scearce, Richard M.; Soderberg, Kelly A.; Cohen, Myron; Kaminga, Gift; Louder, Mark K.; Tran, Lillan M.; Chen, Yue; Cai, Fangping; Chen, Sheri; Moquin, Stephanie; Du, Xiulian; Joyce, Gordon M.; Srivatsan, Sanjay; Zhang, Baoshan; Zheng, Anqi; Shaw, George M.; Hahn, Beatrice H.; Kepler, Thomas B.; Korber, Bette T.M.; Kwong, Peter D.; Mascola, John R.; Haynes, Barton F.

    2013-01-01

    Current HIV-1 vaccines elicit strain-specific neutralizing antibodies. However, cross-reactive neutralizing antibodies arise in ~20% of HIV-1-infected individuals, and details of their generation could provide a roadmap for effective vaccination. Here we report the isolation, evolution and structure of a broadly neutralizing antibody from an African donor followed from time of infection. The mature antibody, CH103, neutralized ~55% of HIV-1 isolates, and its co-crystal structure with gp120 revealed a novel loop-based mechanism of CD4-binding site recognition. Virus and antibody gene sequencing revealed concomitant virus evolution and antibody maturation. Notably, the CH103-lineage unmutated common ancestor avidly bound the transmitted/founder HIV-1 envelope glycoprotein, and evolution of antibody neutralization breadth was preceded by extensive viral diversification in and near the CH103 epitope. These data elucidate the viral and antibody evolution leading to induction of a lineage of HIV-1 broadly neutralizing antibodies and provide insights into strategies to elicit similar antibodies via vaccination. PMID:23552890

  18. The function and affinity maturation of HIV-1 gp120-specific monoclonal antibodies derived from colostral B cells.

    PubMed

    Jeffries, T L; Sacha, C R; Pollara, J; Himes, J; Jaeger, F H; Dennison, S M; McGuire, E; Kunz, E; Eudailey, J A; Trama, A M; LaBranche, C; Fouda, G G; Wiehe, K; Montefiori, D C; Haynes, B F; Liao, H-X; Ferrari, G; Alam, S M; Moody, M A; Permar, S R

    2016-03-01

    Despite the risk of transmitting HIV-1, mothers in resource-poor areas are encouraged to breastfeed their infants because of beneficial immunologic and nutritional factors in milk. Interestingly, in the absence of antiretroviral prophylaxis, the overwhelming majority of HIV-1-exposed, breastfeeding infants are naturally protected from infection. To understand the role of HIV-1 envelope (Env)-specific antibodies in breast milk in natural protection against infant virus transmission, we produced 19 HIV-1 Env-specific monoclonal antibodies (mAbs) isolated from colostrum B cells of HIV-1-infected mothers and investigated their specificity, evolution, and anti-HIV-1 functions. Despite the previously reported genetic compartmentalization and gp120-specific bias of colostrum HIV Env-specific B cells, the colostrum Env-specific mAbs described here demonstrated a broad range of gp120 epitope specificities and functions, including inhibition of epithelial cell binding and dendritic cell-mediated virus transfer, neutralization, and antibody-dependent cellular cytotoxicity. We also identified divergent patterns of colostrum Env-specific B-cell lineage evolution with respect to crossreactivity to gastrointestinal commensal bacteria, indicating that commensal bacterial antigens play a role in shaping the local breast milk immunoglobulin G (IgG) repertoire. Maternal vaccine strategies to specifically target this breast milk B-cell population may be necessary to achieve safe breastfeeding for all HIV-1-exposed infants. PMID:26242599

  19. The function and affinity maturation of HIV-1 gp120-specific monoclonal antibodies derived from colostral B cells

    PubMed Central

    Jeffries, Thomas L; Sacha, CR; Pollara, Justin; Himes, Jon; Jaeger, Frederick H; Dennison, S Moses; McGuire, Erin; Kunz, Erika; Eudailey, Joshua A; Trama, Ashley M; LaBranche, Celia; Fouda, Genevieve G; Wiehe, Kevin; Montefiori, David C; Haynes, Barton F; Liao, Hua-Xin; Ferrari, Guido; Alam, S Munir; Moody, M Anthony; Permar, Sallie R

    2015-01-01

    Despite the risk of transmitting HIV-1, mothers in resource-poor areas are encouraged to breastfeed their infants due to beneficial immunologic and nutritional factors in milk. Interestingly, in the absence of antiretroviral prophylaxis, the overwhelming majority of HIV-1-exposed, breastfeeding infants are naturally protected from infection. To understand the role of HIV-1 Envelope (Env)-specific antibodies in breast milk in natural protection against infant virus transmission, we produced 19 HIV-1 Env-specific monoclonal antibodies (mAbs) isolated from colostrum B cells of HIV-1-infected mothers and investigated their specificity, evolution and anti-HIV-1 functions. Despite the previously reported genetic compartmentalization and gp120-specific bias of colostrum HIV Env-specific B cells, the colostrum Env-specific mAbs described here demonstrated a broad range of gp120 epitope specificities and functions, including inhibition of epithelial cell binding and dendritic cell mediated virus transfer, neutralization, and antibody-dependent cellular cytotoxicity. Interestingly, we also identified divergent patterns of colostrum Env-specific B cell lineage evolution with respect to cross-reactivity to gastrointestinal commensal bacteria, indicating that commensal bacterial antigens play a role in shaping the local breast milk IgG repertoire. Maternal vaccine strategies to specifically target this breast milk B cell population may be necessary to achieve safe breastfeeding for all HIV-1-exposed infants. PMID:26242599

  20. Dynamic correlation between intrahost HIV-1 quasispecies evolution and disease progression.

    PubMed

    Lee, Ha Youn; Perelson, Alan S; Park, Su-Chan; Leitner, Thomas

    2008-12-01

    Quantifying the dynamics of intrahost HIV-1 sequence evolution is one means of uncovering information about the interaction between HIV-1 and the host immune system. In the chronic phase of infection, common dynamics of sequence divergence and diversity have been reported. We developed an HIV-1 sequence evolution model that simulated the effects of mutation and fitness of sequence variants. The amount of evolution was described by the distance from the founder strain, and fitness was described by the number of offspring a parent sequence produces. Analysis of the model suggested that the previously observed saturation of divergence and decrease of diversity in later stages of infection can be explained by a decrease in the proportion of offspring that are mutants as the distance from the founder strain increases rather than due to an increase of viral fitness. The prediction of the model was examined by performing phylogenetic analysis to estimate the change in the rate of evolution during infection. In agreement with our modeling, in 13 out of 15 patients (followed for 3-12 years) we found that the rate of intrahost HIV-1 evolution was not constant but rather slowed down at a rate correlated with the rate of CD4+ T-cell decline. The correlation between the dynamics of the evolutionary rate and the rate of CD4+ T-cell decline, coupled with our HIV-1 sequence evolution model, explains previously conflicting observations of the relationships between the rate of HIV-1 quasispecies evolution and disease progression.

  1. Cobalamin inhibition of HIV-1 integrase and integration of HIV-1 DNA into cellular DNA.

    PubMed

    Weinberg, J B; Shugars, D C; Sherman, P A; Sauls, D L; Fyfe, J A

    1998-05-19

    Our prior studies showed that certain cobalamins inhibit productive HIV-1 infection of primary cultures of blood lymphocytes and monocytes. We demonstrate here that this antiviral activity may be mediated by an inhibition of HIV-1 integrase, an enzyme required for productive infection. Purified recombinant HIV-1 integrase activity was inhibited in vitro by hydroxocobalamin (OH-Cbl), methylcobalamin (Me-Cbl), adenosylcobalamin (Ado-Cbl), and dicyanocobinamide (CN2-Cbi) with IC50 values of approximately 17, 17, 17, and 4 microM, respectively. The agents inhibited HIV-1 infection of cultured monocytes (IC50 values for OH-Cbl, Me-Cbl, Ado-Cbl, and CN2-Cbi of 6, 7, 4, and 1 microM, respectively) and of cultured lymphocytes (IC50 values of 60, 50, 60, and 11 microM, respectively). Experiments using cultured monocytes or lymphocytes demonstrated that OH-Cbl inhibited integration of HIV-1 DNA into cellular DNA. Thus, cobalamins and cobinamides represent novel inhibitors of HIV-1 integrase. These or related agents may be useful as anti-viral treatments that target HIV-1 integrase. PMID:9610370

  2. A Scoring Tool to Identify East African HIV-1 Serodiscordant Partnerships with a High Likelihood of Pregnancy

    PubMed Central

    Heffron, Renee; Cohen, Craig R.; Ngure, Kenneth; Bukusi, Elizabeth; Were, Edwin; Kiarie, James; Mugo, Nelly; Celum, Connie; Baeten, Jared M.

    2015-01-01

    Introduction HIV-1 prevention programs targeting HIV-1 serodiscordant couples need to identify couples that are likely to become pregnant to facilitate discussions about methods to minimize HIV-1 risk during pregnancy attempts (i.e. safer conception) or effective contraception when pregnancy is unintended. A clinical prediction tool could be used to identify HIV-1 serodiscordant couples with a high likelihood of pregnancy within one year. Methods Using standardized clinical prediction methods, we developed and validated a tool to identify heterosexual East African HIV-1 serodiscordant couples with an increased likelihood of becoming pregnant in the next year. Datasets were from three prospectively followed cohorts, including nearly 7,000 couples from Kenya and Uganda participating in HIV-1 prevention trials and delivery projects. Results The final score encompassed the age of the woman, woman’s number of children living, partnership duration, having had condomless sex in the past month, and non-use of an effective contraceptive. The area under the curve (AUC) for the probability of the score to correctly predict pregnancy was 0.74 (95% CI 0.72–0.76). Scores ≥7 predicted a pregnancy incidence of >17% per year and captured 78% of the pregnancies. Internal and external validation confirmed the predictive ability of the score. Discussion A pregnancy likelihood score encompassing basic demographic, clinical and behavioral factors defined African HIV-1 serodiscordant couples with high one-year pregnancy incidence rates. This tool could be used to engage African HIV-1 serodiscordant couples in counseling discussions about fertility intentions in order to offer services for safer conception or contraception that align with their reproductive goals. PMID:26720412

  3. HIV-1 Capsid: The Multifaceted Key Player in HIV-1 infection

    PubMed Central

    Campbell, Edward M.; Hope, Thomas J.

    2016-01-01

    In a mature, infectious HIV-1 virion, the viral genome is housed within a conical capsid core comprised of the viral capsid (CA) protein. The CA protein, and the structure into which it assembles, facilitate virtually every step of infection through a series of interactions with multiple host cell factors. This review describes our understanding of the interactions between the viral capsid core and several cellular factors that enable efficient HIV-1 genome replication, timely core disassembly, nuclear import and the integration of the viral genome into the genome of the target cell. We then discuss how elucidating these interactions can reveal new targets for therapeutic interactions against HIV-1. PMID:26179359

  4. HIV-1 transcription and latency: an update

    PubMed Central

    2013-01-01

    Combination antiretroviral therapy, despite being potent and life-prolonging, is not curative and does not eradicate HIV-1 infection since interruption of treatment inevitably results in a rapid rebound of viremia. Reactivation of latently infected cells harboring transcriptionally silent but replication-competent proviruses is a potential source of persistent residual viremia in cART-treated patients. Although multiple reservoirs may exist, the persistence of resting CD4+ T cells carrying a latent infection represents a major barrier to eradication. In this review, we will discuss the latest reports on the molecular mechanisms that may regulate HIV-1 latency at the transcriptional level, including transcriptional interference, the role of cellular factors, chromatin organization and epigenetic modifications, the viral Tat trans-activator and its cellular cofactors. Since latency mechanisms may also operate at the post-transcriptional level, we will consider inhibition of nuclear RNA export and inhibition of translation by microRNAs as potential barriers to HIV-1 gene expression. Finally, we will review the therapeutic approaches and clinical studies aimed at achieving either a sterilizing cure or a functional cure of HIV-1 infection, with a special emphasis on the most recent pharmacological strategies to reactivate the latent viruses and decrease the pool of viral reservoirs. PMID:23803414

  5. HIV-1 therapy with monoclonal antibody 3BNC117 elicits host immune responses against HIV-1.

    PubMed

    Schoofs, Till; Klein, Florian; Braunschweig, Malte; Kreider, Edward F; Feldmann, Anna; Nogueira, Lilian; Oliveira, Thiago; Lorenzi, Julio C C; Parrish, Erica H; Learn, Gerald H; West, Anthony P; Bjorkman, Pamela J; Schlesinger, Sarah J; Seaman, Michael S; Czartoski, Julie; McElrath, M Juliana; Pfeifer, Nico; Hahn, Beatrice H; Caskey, Marina; Nussenzweig, Michel C

    2016-05-20

    3BNC117 is a broad and potent neutralizing antibody to HIV-1 that targets the CD4 binding site on the viral envelope spike. When administered passively, this antibody can prevent infection in animal models and suppress viremia in HIV-1-infected individuals. Here we report that HIV-1 immunotherapy with a single injection of 3BNC117 affects host antibody responses in viremic individuals. In comparison to untreated controls that showed little change in their neutralizing activity over a 6-month period, 3BNC117 infusion significantly improved neutralizing responses to heterologous tier 2 viruses in nearly all study participants. We conclude that 3BNC117-mediated immunotherapy enhances host humoral immunity to HIV-1. PMID:27199429

  6. Enhanced clearance of HIV-1-infected cells by broadly neutralizing antibodies against HIV-1 in vivo.

    PubMed

    Lu, Ching-Lan; Murakowski, Dariusz K; Bournazos, Stylianos; Schoofs, Till; Sarkar, Debolina; Halper-Stromberg, Ariel; Horwitz, Joshua A; Nogueira, Lilian; Golijanin, Jovana; Gazumyan, Anna; Ravetch, Jeffrey V; Caskey, Marina; Chakraborty, Arup K; Nussenzweig, Michel C

    2016-05-20

    Antiretroviral drugs and antibodies limit HIV-1 infection by interfering with the viral life cycle. In addition, antibodies also have the potential to guide host immune effector cells to kill HIV-1-infected cells. Examination of the kinetics of HIV-1 suppression in infected individuals by passively administered 3BNC117, a broadly neutralizing antibody, suggested that the effects of the antibody are not limited to free viral clearance and blocking new infection but also include acceleration of infected cell clearance. Consistent with these observations, we find that broadly neutralizing antibodies can target CD4(+) T cells infected with patient viruses and can decrease their in vivo half-lives by a mechanism that requires Fcγ receptor engagement in a humanized mouse model. The results indicate that passive immunotherapy can accelerate elimination of HIV-1-infected cells. PMID:27199430

  7. Interferon-α Subtypes in an Ex Vivo Model of Acute HIV-1 Infection: Expression, Potency and Effector Mechanisms.

    PubMed

    Harper, Michael S; Guo, Kejun; Gibbert, Kathrin; Lee, Eric J; Dillon, Stephanie M; Barrett, Bradley S; McCarter, Martin D; Hasenkrug, Kim J; Dittmer, Ulf; Wilson, Cara C; Santiago, Mario L

    2015-01-01

    HIV-1 is transmitted primarily across mucosal surfaces and rapidly spreads within the intestinal mucosa during acute infection. The type I interferons (IFNs) likely serve as a first line of defense, but the relative expression and antiviral properties of the 12 IFNα subtypes against HIV-1 infection of mucosal tissues remain unknown. Here, we evaluated the expression of all IFNα subtypes in HIV-1-exposed plasmacytoid dendritic cells by next-generation sequencing. We then determined the relative antiviral potency of each IFNα subtype ex vivo using the human intestinal Lamina Propria Aggregate Culture model. IFNα subtype transcripts from the centromeric half of the IFNA gene complex were highly expressed in pDCs following HIV-1 exposure. There was an inverse relationship between IFNA subtype expression and potency. IFNα8, IFNα6 and IFNα14 were the most potent in restricting HIV-1 infection. IFNα2, the clinically-approved subtype, and IFNα1 were both highly expressed but exhibited relatively weak antiviral activity. The relative potencies correlated with binding affinity to the type I IFN receptor and the induction levels of HIV-1 restriction factors Mx2 and Tetherin/BST-2 but not APOBEC3G, F and D. However, despite the lack of APOBEC3 transcriptional induction, the higher relative potency of IFNα8 and IFNα14 correlated with stronger inhibition of virion infectivity, which is linked to deaminase-independent APOBEC3 restriction activity. By contrast, both potent (IFNα8) and weak (IFNα1) subtypes significantly induced HIV-1 GG-to-AG hypermutation. The results unravel non-redundant functions of the IFNα subtypes against HIV-1 infection, with strong implications for HIV-1 mucosal immunity, viral evolution and IFNα-based functional cure strategies. PMID:26529416

  8. Interferon-α Subtypes in an Ex Vivo Model of Acute HIV-1 Infection: Expression, Potency and Effector Mechanisms

    PubMed Central

    Harper, Michael S.; Guo, Kejun; Gibbert, Kathrin; Lee, Eric J.; Dillon, Stephanie M.; Barrett, Bradley S.; McCarter, Martin D.; Hasenkrug, Kim J.; Dittmer, Ulf; Wilson, Cara C.; Santiago, Mario L.

    2015-01-01

    HIV-1 is transmitted primarily across mucosal surfaces and rapidly spreads within the intestinal mucosa during acute infection. The type I interferons (IFNs) likely serve as a first line of defense, but the relative expression and antiviral properties of the 12 IFNα subtypes against HIV-1 infection of mucosal tissues remain unknown. Here, we evaluated the expression of all IFNα subtypes in HIV-1-exposed plasmacytoid dendritic cells by next-generation sequencing. We then determined the relative antiviral potency of each IFNα subtype ex vivo using the human intestinal Lamina Propria Aggregate Culture model. IFNα subtype transcripts from the centromeric half of the IFNA gene complex were highly expressed in pDCs following HIV-1 exposure. There was an inverse relationship between IFNA subtype expression and potency. IFNα8, IFNα6 and IFNα14 were the most potent in restricting HIV-1 infection. IFNα2, the clinically-approved subtype, and IFNα1 were both highly expressed but exhibited relatively weak antiviral activity. The relative potencies correlated with binding affinity to the type I IFN receptor and the induction levels of HIV-1 restriction factors Mx2 and Tetherin/BST-2 but not APOBEC3G, F and D. However, despite the lack of APOBEC3 transcriptional induction, the higher relative potency of IFNα8 and IFNα14 correlated with stronger inhibition of virion infectivity, which is linked to deaminase-independent APOBEC3 restriction activity. By contrast, both potent (IFNα8) and weak (IFNα1) subtypes significantly induced HIV-1 GG-to-AG hypermutation. The results unravel non-redundant functions of the IFNα subtypes against HIV-1 infection, with strong implications for HIV-1 mucosal immunity, viral evolution and IFNα-based functional cure strategies. PMID:26529416

  9. Glutamate metabolism in HIV-1 infected macrophages: Role of HIV-1 Vpr.

    PubMed

    Datta, Prasun K; Deshmane, Satish; Khalili, Kamel; Merali, Salim; Gordon, John C; Fecchio, Chiara; Barrero, Carlos A

    2016-09-01

    HIV-1 infected macrophages play a significant role in the neuropathogenesis of AIDS. HIV-1 viral protein R (Vpr) not only facilitates HIV-1 infection but also contribute to long-lived persistence in macrophages. Our previous studies using SILAC-based proteomic analysis showed that the expression of critical metabolic enzymes in the glycolytic pathway and tricarboxylic acid (TCA) cycle were altered in response to Vpr expression in macrophages. We hypothesized that Vpr-induced modulation of glycolysis and TCA cycle regulates glutamate metabolism and release in HIV-1 infected macrophages. We assessed the amount of specific metabolites induced by Vpr and HIV-1 in macrophages at the intracellular and extracellular level in a time-dependent manner utilizing multiple reaction monitoring (MRM) targeted metabolomics. In addition, stable isotope-labeled glucose and an MRM targeted metabolomics assay were used to evaluate the de novo synthesis and release of glutamate in Vpr overexpressing macrophages and HIV-1 infected macrophages, throughout the metabolic flux of glycolytic pathway and TCA cycle activation. The metabolic flux studies demonstrated an increase in glucose uptake, glutamate release and accumulation of α-ketoglutarate (α-KG) and glutamine in the extracellular milieu in Vpr expressing and HIV-1 infected macrophages. Interestingly, glutamate pools and other intracellular intermediates (glucose-6-phosphate (G6P), fructose-6-phosphate (F6P), citrate, malate, α-KG, and glutamine) showed a decreased trend except for fumarate, in contrast to the glutamine accumulation observed in the extracellular space in Vpr overexpressing macrophages. Our studies demonstrate that dysregulation of mitochondrial glutamate metabolism induced by Vpr in HIV-1 infected macrophages commonly seen, may contribute to neurodegeneration via excitotoxic mechanisms in the context of NeuroAIDS. PMID:27245560

  10. Progesterone augments cell susceptibility to HIV-1 and HIV-1/HSV-2 co-infections.

    PubMed

    Ragupathy, Viswanath; Xue, Wang; Tan, Ji; Devadas, Krishnakumar; Gao, Yamei; Hewlett, Indira

    2016-10-01

    In human immunodeficiency virus type 1 (HIV-1)-infected women, oral or injectable progesterone containing contraceptive pills may enhance HIV-1 acquisition in vivo, and the mechanism by which this occurs is not fully understood. In developing countries, Herpes simplex virus type-2 (HSV-2) co-infection has been shown to be a risk for increase of HIV-1 acquisition and, if co-infected women use progesterone pills, infections may increase several fold. In this study, we used an in vitro cell culture system to study the effects of progesterone on HIV-1 replication and to explore the molecular mechanism of progesterone effects on infected cells. In our in vitro model, CEMss cells (lymphoblastoid cell line) were infected with either HIV-1 alone or co-infected with HSV-2. HIV-1 viral load was measured with and without sex hormone treatment. Progesterone-treated cells showed an increase in HIV-1 viral load (1411.2 pg/mL) compared with cells without progesterone treatment (993.1 pg/mL). Increased cell death was noted with HSV-2 co-infection and in progesterone-treated cells. Similar observations were noted in peripheral blood mononuclear cells (PBMC) cells derived from three female donors. Progesterone-treated cells also showed reduced antiviral efficacy. Inflammatory cytokines and associations with biomarkers of disease progression were explored. Progesterone upregulated inflammatory cytokines and chemokines conversely and downregulated anti-apoptotic Bcl-2 expression. Nuclear protein analysis by electrophoretic mobility shift assay showed the association of progesterone with progesterone response element (PRE), which may lead to downregulation of Bcl-2. These data indicate that progesterone treatment enhances HIV-1 replication in infected cells and co-infection with HSV-2 may further fuel this process. PMID:27538988

  11. SAMHD1 Limits HIV-1 Antigen Presentation by Monocyte-Derived Dendritic Cells

    PubMed Central

    Bruel, Timothée; Cardinaud, Sylvain; Porrot, Françoise; Prado, Julia G.; Moris, Arnaud

    2015-01-01

    ABSTRACT Monocyte-derived dendritic cells (MDDC) stimulate CD8+ cytotoxic T lymphocytes (CTL) by presenting endogenous and exogenous viral peptides via major histocompatibility complex class I (MHC-I) molecules. MDDC are poorly susceptible to HIV-1, in part due to the presence of SAMHD1, a cellular enzyme that depletes intracellular deoxynucleoside triphosphates (dNTPs) and degrades viral RNA. Vpx, an HIV-2/SIVsm protein absent from HIV-1, antagonizes SAMHD1 by inducing its degradation. The impact of SAMHD1 on the adaptive cellular immune response remains poorly characterized. Here, we asked whether SAMHD1 modulates MHC-I-restricted HIV-1 antigen presentation. Untreated MDDC or MDDC pretreated with Vpx were exposed to HIV-1, and antigen presentation was examined by monitoring the activation of an HIV-1 Gag-specific CTL clone. SAMHD1 depletion strongly enhanced productive infection of MDDC as well as endogenous HIV-1 antigen presentation. Time-lapse microscopy analysis demonstrated that in the absence of SAMHD1, the CTL rapidly killed infected MDDC. We also report that various transmitted/founder (T/F) HIV-1 strains poorly infected MDDC and, as a consequence, did not stimulate CTL. Vesicular stomatitis virus glycoprotein (VSV-G) pseudotyping of T/F alleviated a block in viral entry and induced antigen presentation only in the absence of SAMHD1. Furthermore, by using another CTL clone that mostly recognizes incoming HIV-1 antigens, we demonstrate that SAMHD1 does not influence exogenous viral antigen presentation. Altogether, our results demonstrate that the antiviral activity of SAMHD1 impacts antigen presentation by DC, highlighting the link that exists between restriction factors and adaptive immune responses. IMPORTANCE Upon viral infection, DC may present antigens derived from incoming viral material in the absence of productive infection of DC or from newly synthesized viral proteins. In the case of HIV, productive infection of DC is blocked at an early

  12. [Molecular characterization of complex recombinant HIV-1 CRF06_cpx subtype detected in Turkey].

    PubMed

    Sayan, Murat; Kaptan, Figen; Ormen, Bahar; Türker, Nesrin

    2014-01-01

    A major proportion of the global HIV infections is caused by group M of HIV-1 genotype and to date approximately nine subtypes (A, B, C, D, F, G, H, J, K) and 50 circulating recombinant forms (CRFs) have been recognized. Recombinants between different HIV-1 group M subtypes are designated as CRF. The extension 'cpx', for complex, is given if the CRF consists of contributions from three or more different subtypes but the composition of the subtype is not given. The objective of this study was to present, for the first time an HIV-1 positive married couple infected with CRF06_cpx subtype in Izmir, Turkey. A 39-year-old male patient who admitted to hospital with the complaints of oral candidiasis and zona, was found to be anti-HIV positive. CD4+ T lymphocyte count was 21 cells/mm3 and plasma HIV-1 RNA level was 56.380 copies/ml. He reported unprotected heterosexual contact with multiple partners including African women during his stay in Saudi Arabia between 1996 and 2002. After his diagnosis, his 37-year-old wife was screened for HIV infection and she was also found anti-HIV positive, with CD4+ T cell count of 122 cells/mm3. However, her results of basal plasma HIV-1 RNA could not be obtained because of an internal control error. HIV-1 strains were analysed for subtyping, recombination and drug resistance mutations with pol gene region sequencing. HIV-1 sequences were subtyped as CRF06_cpx after phylogenetic analysis using neighbor-joining method. According to the recombination analysis, HIV-1 pol gene regions consisted of group M subtype G, A, D, and B in the male patient and G K, A, F, and D in the female patient. While L10I + L33F mutation associated with protease inhibitor (PI) resistance was detected in both of the patients, K219N mutation associated with nucleoside reverse transcriptase inhibitor (NRTI) resistance was detected only in the male patient. In conclusion, HIV-1 molecular epidemiology studies are important tools for tracking transmission patterns and

  13. The Global Transmission Network of HIV-1

    PubMed Central

    Wertheim, Joel O.; Leigh Brown, Andrew J.; Hepler, N. Lance; Mehta, Sanjay R.; Richman, Douglas D.; Smith, Davey M.; Kosakovsky Pond, Sergei L.

    2014-01-01

    Human immunodeficiency virus type 1 (HIV-1) is pandemic, but its contemporary global transmission network has not been characterized. A better understanding of the properties and dynamics of this network is essential for surveillance, prevention, and eventual eradication of HIV. Here, we apply a simple and computationally efficient network-based approach to all publicly available HIV polymerase sequences in the global database, revealing a contemporary picture of the spread of HIV-1 within and between countries. This approach automatically recovered well-characterized transmission clusters and extended other clusters thought to be contained within a single country across international borders. In addition, previously undescribed transmission clusters were discovered. Together, these clusters represent all known modes of HIV transmission. The extent of international linkage revealed by our comprehensive approach demonstrates the need to consider the global diversity of HIV, even when describing local epidemics. Finally, the speed of this method allows for near-real-time surveillance of the pandemic's progression. PMID:24151309

  14. Latency: the hidden HIV-1 challenge

    PubMed Central

    Marcello, Alessandro

    2006-01-01

    Eradication of HIV-1 from an infected individual cannot be achieved by current regimens. Viral reservoirs established early during the infection remain unaffected by anti-retroviral therapy for a long time and are able to replenish systemic infection upon interruption of the treatment. Therapeutic targeting of viral latency will require a better understanding of the basic mechanisms underlying the establishment and long-term maintenance of HIV-1 in resting memory CD4 T cells, the most prominent reservoir of transcriptionally silent provirus. Since the molecular mechanisms that permit long term transcriptional control of proviral gene expression in these cells are still obscure, this review aims at summarizing the various aspects of the problem that need to be considered. In particular, this review will focus the attention on the control of transcription imposed by chromatin through various epigenetic mechanisms. Exploring the molecular details of viral latency will provide new insights for eventual future therapeutics that aim at viral eradication. PMID:16412247

  15. Tertiary Element Interaction in HIV-1 TAR.

    PubMed

    Krawczyk, Konrad; Sim, Adelene Y L; Knapp, Bernhard; Deane, Charlotte M; Minary, Peter

    2016-09-26

    HIV-1 replication requires binding to occur between Trans-activation Response Element (TAR) RNA and the TAT protein. This TAR-TAT binding depends on the conformation of TAR, and therapeutic development has attempted to exploit this dynamic behavior. Here we simulate TAR dynamics in the context of mutations inhibiting TAR binding. We find that two tertiary elements, the apical loop and the bulge, can interact directly, and this interaction may be linked to the affinity of TAR for TAT. PMID:27500460

  16. Nanochemistry-based immunotherapy for HIV-1.

    PubMed

    Lori, F; Calarota, S A; Lisziewicz, J

    2007-01-01

    Highly active antiretroviral treatment (HAART), i.e. the combination of three or more drugs against human immunodeficiency virus type 1 (HIV-1), has greatly improved the clinical outcome of HIV-1-infected individuals. However, HAART is unable to reconstitute HIV-specific immunity and eradicate the virus. Several observations in primate models and in humans support the notion that cell-mediated immunity can control viral replication and slow disease progression. Thus, besides drugs, an immunotherapy that induces long-lasting HIV-specific T-cell responses could play a role in the treatment of HIV/AIDS. To induce such immune responses, DermaVir Patch has been developed. DermaVir consists of an HIV-1 antigen-encoding plasmid DNA that is chemically formulated in a nanoparticle. DermaVir is administered under a patch after a skin preparation that supports the delivery of the nanoparticle to Langerhans cells (LC). Epidermal LC trap and transport the nanomedicine to draining lymph nodes. While in transit, LC mature into dendritic cells (DC), which can efficiently present the DNA-encoded antigens to naïve T-cells for the induction of cellular immunity. Pre-clinical studies and Phase I clinical testing of DermaVir in HIV-1-infected individuals have demonstrated the safety and tolerability of DermaVir Patch. To further modulate cellular immunity, molecular adjuvants might be added into the nanoparticle. DermaVir Patch represents a new nanomedicine platform for immunotherapy of HIV/AIDS. In this review, the antiviral activity of DermaVir-induced cellular immunity is discussed. Furthermore, the action of some cytokines currently being tested as adjuvants are highlighted and the adjuvant effect of cytokine plasmid DNA included in the DermaVir nanoparticle is reviewed.

  17. Maturation of the viral core enhances the fusion of HIV-1 particles with primary human T cells and monocyte-derived macrophages

    SciTech Connect

    Jiang Jiyang; Aiken, Christopher . E-mail: chris.aiken@vanderbilt.edu

    2006-03-15

    HIV-1 infection requires fusion of viral and cellular membranes in a reaction catalyzed by the viral envelope proteins gp120 and gp41. We recently reported that efficient HIV-1 particle fusion with target cells is linked to maturation of the viral core by an activity of the gp41 cytoplasmic domain. Here, we show that maturation enhances the fusion of a variety of recombinant viruses bearing primary and laboratory-adapted Env proteins with primary human CD4{sup +} T cells. Overall, HIV-1 fusion was more dependent on maturation for viruses bearing X4-tropic envelope proteins than for R5-tropic viruses. Fusion of HIV-1 with monocyte-derived macrophages was also dependent on particle maturation. We conclude that the ability to couple fusion to particle maturation is a common feature of HIV-1 Env proteins and may play an important role during HIV-1 replication in vivo.

  18. Long-Term Non-Progression and Broad HIV-1-Specific Proliferative T-Cell Responses

    PubMed Central

    Imami, Nesrina; Westrop, Samantha J.; Grageda, Nathali; Herasimtschuk, Anna A.

    2013-01-01

    Complex mechanisms underlying the maintenance of fully functional, proliferative, HIV-1-specific T-cell responses involve processes from early T-cell development through to the final stages of T-cell differentiation and antigen recognition. Virus-specific proliferative CD4 and CD8 T-cell responses, important for the control of infection, are observed in some HIV-1+ patients during early stages of disease, and are maintained in long-term non-progressing subjects. In the vast majority of HIV-1+ patients, full immune functionality is lost when proliferative HIV-1-specific T-cell responses undergo a variable progressive decline throughout the course of chronic infection. This appears irreparable despite administration of potent combination antiretroviral therapy, which to date is non-curative, necessitating life-long administration and the development of effective, novel, therapeutic interventions. While a sterilizing cure, involving clearance of virus from the host, remains a primary aim, a “functional cure” may be a more feasible goal with considerable impact on worldwide HIV-1 infection. Such an approach would enable long-term co-existence of host and virus in the absence of toxic and costly drugs. Effective immune homeostasis coupled with a balanced response appropriately targeting conserved viral antigens, in a manner that avoids hyperactivation and exhaustion, may prove to be the strongest correlate of durable viral control. This review describes novel concepts underlying full immune functionality in the context of HIV-1 infection, which may be utilized in future strategies designed to improve upon existing therapy. The aim will be to induce long-term non-progressor or elite controller status in every infected host, through immune-mediated control of viremia and reduction of viral reservoirs, leading to lower HIV-1 transmission rates. PMID:23459797

  19. HIV-1 infection kinetics in tissue cultures.

    PubMed

    Spouge, J I; Shrager, R I; Dimitrov, D S

    1996-11-01

    Despite intensive experimental work on HIV-1, very little theoretical work has focused on HIV-1 spread in tissue culture. This article uses two systems of ordinary differential equations to model two modes of viral spread, cell-free virus and cell-to-cell contact. The two models produce remarkably similar qualitative results. Simulations using realistic parameter regimes showed that starting with a small fraction of cells infected, both cell-free viral spread and direct cell-to-cell transmission give an initial exponential phase of viral growth, followed by either a crash or a gradual decline, extinguishing the culture. Under some conditions, an oscillatory phase may precede the extinction. Some previous models of in vivo HIV-1 infection oscillate, but only in unrealistic parameter regimes. Experimental tissue infections sometimes display several sequential cycles of oscillation, however, so our models can at least mimic them qualitatively. Significantly, the models show that infective oscillations can be explained by infection dynamics; biological heterogeneity is not required. The models also display proportionality between infected cells and cell-free virus, which is reassuringly consistent with assumptions about the equivalence of several measures of viral load, except that the proportionality requires a relatively constant total cell concentration. Tissue culture parameter values can be determined from accurate, controlled experiments. Therefore, if verified, our models should make interpreting experimental data and extrapolating it to in vivo conditions sharper and more reliable.

  20. Progress in HIV-1 Vaccine Development

    PubMed Central

    Haynes, Barton F.; McElrath, M. Juliana

    2014-01-01

    Purpose of the Review In this review, examples of recent progress in HIV-1 vaccine research are discussed. Recent Findings New insights from the immune correlates analyses of the RV144 efficacy trial have accelerated vaccine development with leads to follow in non-human primate studies and improved vaccine designs. Several new vaccine vector approaches offer promise in exquisite control of acute infection and in improving the breadth of T cell responses. New targets of broadly neutralizing antibodies (BnAbs) have been elucidated, and improved understanding of how the human host controls BnAb development have emerged from BnAb knockin mice and from analyses of BnAb maturation and virus evolution in subjects followed from the time of HIV-1 transmission to BnAb induction. Summary Based on these observations, it is clear that development of a successful HIV-1 vaccine will require new vaccine approaches and iterative testing of immunogens in well-designed animal and human trials. PMID:23743722

  1. Nup153 and Nup98 bind the HIV-1 core and contribute to the early steps of HIV-1 replication

    SciTech Connect

    Di Nunzio, Francesca; Fricke, Thomas; Miccio, Annarita; Valle-Casuso, Jose Carlos; Perez, Patricio; Souque, Philippe; Rizzi, Ermanno; Severgnini, Marco; Mavilio, Fulvio; Charneau, Pierre; Diaz-Griffero, Felipe

    2013-05-25

    The early steps of HIV-1 replication involve the entry of HIV-1 into the nucleus, which is characterized by viral interactions with nuclear pore components. HIV-1 developed an evolutionary strategy to usurp the nuclear pore machinery and chromatin in order to integrate and efficiently express viral genes. In the current work, we studied the role of nucleoporins 153 and 98 (Nup153 and Nup98) in infection of human Jurkat lymphocytes by HIV-1. We showed that Nup153-depleted cells exhibited a defect in nuclear import, while depletion of Nup 98 caused a slight defect in HIV integration. To explore the biochemical viral determinants for the requirement of Nup153 and Nup98 during HIV-1 infection, we tested the ability of these nucleoporins to interact with HIV-1 cores. Our findings showed that both nucleoporins bind HIV-1 cores suggesting that this interaction is important for HIV-1 nuclear import and/or integration. Distribution analysis of integration sites in Nup153-depleted cells revealed a reduced tendency of HIV-1 to integrate in intragenic sites, which in part could account for the large infectivity defect observed in Nup153-depleted cells. Our work strongly supports a role for Nup153 in HIV-1 nuclear import and integration. - Highlights: ► We studied the role of Nup98 and Nup153 in HIV-1 infection. ► Nup98 binds the HIV-1 core and is involved in HIV-1 integration. ► Nup153 binds the HIV-1 core and is involved in HIV-1 nuclear import. ► Depletion of Nup153 decreased the integration of HIV-1 in transcriptionally active sites.

  2. Identification of a small molecule HIV-1 inhibitor that targets the capsid hexamer.

    PubMed

    Xu, Jimmy P; Branson, Jeffrey D; Lawrence, Rae; Cocklin, Simon

    2016-02-01

    The HIV-1 CA protein is an attractive therapeutic target for the development of new antivirals. An inter-protomer pocket within the hexamer configuration of the CA, which is a binding site for key host dependency factors, is an especially appealing region for small molecule targeting. Using a field-based pharmacophore derived from an inhibitor known to interact with this region, coupled to biochemical and biological assessment, we have identified a new compound that inhibits HIV-1 infection and that targets the assembled CA hexamer. PMID:26747394

  3. Suppression of HIV-1 Infectivity by Human Glioma Cells.

    PubMed

    Hoque, Sheikh Ariful; Tanaka, Atsushi; Islam, Salequl; Ahsan, Gias Uddin; Jinno-Oue, Atsushi; Hoshino, Hiroo

    2016-05-01

    HIV-1 infection to the central nervous system (CNS) is very common in AIDS patients. The predominant cell types infected in the brain are monocytes and macrophages, which are surrounded by several HIV-1-resistant cell types, such as astrocytes, oligodendrocytes, neurons, and microvascular cells. The effect of these HIV-1-resistant cells on HIV-1 infection is largely unknown. In this study, we examined the stability of HIV-1 cultured with several human glioblastoma cell lines, for example, NP-2, U87MG, T98G, and A172, to determine whether these HIV-1-resistant brain cells could enhance or suppress HIV-1 infection and thus modulate HIV-1 infection in the CNS. The HIV-1 titer was determined using the MAGIC-5A indicator cell line as well as naturally occurring CD4(+) T cells. We found that the stability of HIV-1 incubated with NP-2 or U87MG cells at 37°C was significantly shorter (half-life, 2.5-4 h) compared to that of HIV-1 incubated with T98G or A172 cells or in culture medium without cells (half-life, 8-18 h). The spent culture media (SCM) of NP-2 and U87MG cells had the ability to suppress both R5- and X4-HIV-1 infection by inhibiting HIV-1 attachment to target cells. This inhibitory effect was eliminated by the treatment of the SCM with chondroitinase ABC but not heparinase, suggesting that the inhibitory factor(s) secreted by NP-2 and U87MG cells was chiefly mediated by chondroitin sulfate (CS) or CS-like moiety. Thus, this study reveals that some but not all glioma cells secrete inhibitory molecules to HIV-1 infection that may contribute in lowering HIV-1 infection in the CNS in vivo. PMID:26650729

  4. Suppression of HIV-1 Infectivity by Human Glioma Cells.

    PubMed

    Hoque, Sheikh Ariful; Tanaka, Atsushi; Islam, Salequl; Ahsan, Gias Uddin; Jinno-Oue, Atsushi; Hoshino, Hiroo

    2016-05-01

    HIV-1 infection to the central nervous system (CNS) is very common in AIDS patients. The predominant cell types infected in the brain are monocytes and macrophages, which are surrounded by several HIV-1-resistant cell types, such as astrocytes, oligodendrocytes, neurons, and microvascular cells. The effect of these HIV-1-resistant cells on HIV-1 infection is largely unknown. In this study, we examined the stability of HIV-1 cultured with several human glioblastoma cell lines, for example, NP-2, U87MG, T98G, and A172, to determine whether these HIV-1-resistant brain cells could enhance or suppress HIV-1 infection and thus modulate HIV-1 infection in the CNS. The HIV-1 titer was determined using the MAGIC-5A indicator cell line as well as naturally occurring CD4(+) T cells. We found that the stability of HIV-1 incubated with NP-2 or U87MG cells at 37°C was significantly shorter (half-life, 2.5-4 h) compared to that of HIV-1 incubated with T98G or A172 cells or in culture medium without cells (half-life, 8-18 h). The spent culture media (SCM) of NP-2 and U87MG cells had the ability to suppress both R5- and X4-HIV-1 infection by inhibiting HIV-1 attachment to target cells. This inhibitory effect was eliminated by the treatment of the SCM with chondroitinase ABC but not heparinase, suggesting that the inhibitory factor(s) secreted by NP-2 and U87MG cells was chiefly mediated by chondroitin sulfate (CS) or CS-like moiety. Thus, this study reveals that some but not all glioma cells secrete inhibitory molecules to HIV-1 infection that may contribute in lowering HIV-1 infection in the CNS in vivo.

  5. Rapid selection of escape mutants by the first CD8 T cell responses in acute HIV-1 infection

    SciTech Connect

    Korber, Bette Tina Marie

    2008-01-01

    The recent failure of a vaccine that primes T cell responses to control primary HIV-1 infection has raised doubts about the role of CD8+ T cells in early HIV-1 infection. We studied four patients who were identified shortly after HIV-1 infection and before seroconversion. In each patient there was very rapid selection of multiple HIV-1 escape mutants in the transmitted virus by CD8 T cells, including examples of complete fixation of non-synonymous substitutions within 2 weeks. Sequencing by single genome amplification suggested that the high rate of virus replication in acute infection gave a selective advantage to virus molecules that contained simultaneous and gained sequential T cell escape mutations. These observations show that whilst early HIV-1 specific CD8 T cells can act against virus, rapid escape means that these T cell responses are unlikely to benefit the patient and may in part explain why current HIV-1 T cell vaccines may not be protective.

  6. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development

    DOE PAGES

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T.; Barouch, Dan H.

    2014-11-14

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth ofmore » IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.« less

  7. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development

    SciTech Connect

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T.; Barouch, Dan H.

    2014-11-14

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.

  8. HIV-1 prevalence in selected Tijuana sub-populations.

    PubMed Central

    Güereña-Burgueño, F; Benenson, A S; Sepúlveda-Amor, J

    1991-01-01

    To assess the prevalence of HIV-1 (human immunodeficiency virus) infection among high-risk populations in Tijuana, Mexico, HIV-1 antibody status was determined and information on risk behavior was obtained from 1,069 individuals in three high-risk groups. The prevalence of HIV-1 among 415 prostitutes was 0.5 percent; 410 prisoners, 1.2 percent; 233 homosexual/bisexual men, 11.6 percent; and 106 intravenous drug abusers, 1.9 percent. The potential for spread of HIV-1 exists in Tijuana despite the current relatively low seroprevalence of HIV-1. PMID:2014864

  9. HIV-1 phylogenetic analysis shows HIV-1 transits through the meninges to brain and peripheral tissues.

    PubMed

    Lamers, Susanna L; Gray, Rebecca R; Salemi, Marco; Huysentruyt, Leanne C; McGrath, Michael S

    2011-01-01

    Brain infection by the human immunodeficiency virus type 1 (HIV-1) has been investigated in many reports with a variety of conclusions concerning the time of entry and degree of viral compartmentalization. To address these diverse findings, we sequenced HIV-1 gp120 clones from a wide range of brain, peripheral and meningeal tissues from five patients who died from several HIV-1 associated disease pathologies. High-resolution phylogenetic analysis confirmed previous studies that showed a significant degree of compartmentalization in brain and peripheral tissue subpopulations. Some intermixing between the HIV-1 subpopulations was evident, especially in patients that died from pathologies other than HIV-associated dementia. Interestingly, the major tissue harboring virus from both the brain and peripheral tissues was the meninges. These results show that (1) HIV-1 is clearly capable of migrating out of the brain, (2) the meninges are the most likely primary transport tissues, and (3) infected brain macrophages comprise an important HIV reservoir during highly active antiretroviral therapy.

  10. Phenotypic Correlates of HIV-1 Macrophage Tropism

    PubMed Central

    Arrildt, Kathryn T.; LaBranche, Celia C.; Joseph, Sarah B.; Dukhovlinova, Elena N.; Graham, William D.; Ping, Li-Hua; Schnell, Gretja; Sturdevant, Christa B.; Kincer, Laura P.; Mallewa, Macpherson; Heyderman, Robert S.; Van Rie, Annelies; Cohen, Myron S.; Spudich, Serena; Price, Richard W.; Montefiori, David C.

    2015-01-01

    ABSTRACT HIV-1 is typically CCR5 using (R5) and T cell tropic (T-tropic), targeting memory CD4+ T cells throughout acute and chronic infections. However, viruses can expand into alternative cells types. Macrophage-tropic (M-tropic) HIV-1 variants have evolved to infect macrophages, which have only low levels of surface CD4. Most M-tropic variants have been isolated from the central nervous system during late-stage chronic infection. We used the HIV-1 env genes of well-defined, subject-matched M-tropic and T-tropic viruses to characterize the phenotypic features of the M-tropic Env protein. We found that, compared to T-tropic viruses, M-tropic viruses infect monocyte-derived macrophages (MDMs) on average 28-fold more efficiently, use low-density CD4 more efficiently, have increased sensitivity to soluble CD4 (sCD4), and show trends toward sensitivity to some CD4 binding site antibodies but no difference in sensitivity to antibodies targeting the CD4-bound conformation. M-tropic viruses also displayed a trend toward resistance to neutralization by monoclonal antibodies targeting the V1/V2 region of Env, suggesting subtle changes in Env protein conformation. The paired M- and T-tropic viruses did not differ in autologous serum neutralization, temperature sensitivity, entry kinetics, intrinsic infectivity, or Env protein incorporation. We also examined viruses with modestly increased CD4 usage. These variants have significant sensitivity to sCD4 and may represent evolutionary intermediates. CD4 usage is strongly correlated with infectivity of MDMs over a wide range of CD4 entry phenotypes. These data suggest that emergence of M-tropic HIV-1 includes multiple steps in which a phenotype of increased sensitivity to sCD4 and enhanced CD4 usage accompany subtle changes in Env conformation. IMPORTANCE HIV-1 typically replicates in CD4+ T cells. However, HIV-1 can evolve to infect macrophages, especially within the brain. Understanding how CCR5-using macrophage-tropic viruses

  11. Improved guanide compounds which bind the CXCR4 co-receptor and inhibit HIV-1 infection.

    PubMed

    Wilkinson, Royce A; Pincus, Seth H; Song, Kejing; Shepard, Joyce B; Weaver, Alan J; Labib, Mohamed E; Teintze, Martin

    2013-04-01

    The G-protein coupled receptor CXCR4 is a co-receptor for HIV-1 infection and is involved in signaling cell migration and proliferation. In a previous study of non-peptide, guanide-based CXCR4-binding compounds, spermine and spermidine phenylguanides inhibited HIV-1 entry at low micromolar concentrations. Subsequently, crystal structures of CXCR4 were used to dock a series of naphthylguanide derivatives of the polyamines spermidine and spermine. Synthesis and evaluation of the naphthylguanide compounds identified our best compound, spermine tris-1-naphthylguanide, which bound CXCR4 with an IC(50) of 40 nM and inhibited the infection of TZM-bl cells with X4, but not R5, strains of HIV-1 with an IC(50) of 50-100 nM.

  12. Viral Evolution and Cytotoxic T Cell Restricted Selection in Acute Infant HIV-1 Infection.

    PubMed

    Garcia-Knight, Miguel A; Slyker, Jennifer; Payne, Barbara Lohman; Pond, Sergei L Kosakovsky; de Silva, Thushan I; Chohan, Bhavna; Khasimwa, Brian; Mbori-Ngacha, Dorothy; John-Stewart, Grace; Rowland-Jones, Sarah L; Esbjörnsson, Joakim

    2016-01-01

    Antiretroviral therapy-naive HIV-1 infected infants experience poor viral containment and rapid disease progression compared to adults. Viral factors (e.g. transmitted cytotoxic T- lymphocyte (CTL) escape mutations) or infant factors (e.g. reduced CTL functional capacity) may explain this observation. We assessed CTL functionality by analysing selection in CTL-targeted HIV-1 epitopes following perinatal infection. HIV-1 gag, pol and nef sequences were generated from a historical repository of longitudinal specimens from 19 vertically infected infants. Evolutionary rate and selection were estimated for each gene and in CTL-restricted and non-restricted epitopes. Evolutionary rate was higher in nef and gag vs. pol, and lower in infants with non-severe immunosuppression vs. severe immunosuppression across gag and nef. Selection pressure was stronger in infants with non-severe immunosuppression vs. severe immunosuppression across gag. The analysis also showed that infants with non-severe immunosuppression had stronger selection in CTL-restricted vs. non-restricted epitopes in gag and nef. Evidence of stronger CTL selection was absent in infants with severe immunosuppression. These data indicate that infant CTLs can exert selection pressure on gag and nef epitopes in early infection and that stronger selection across CTL epitopes is associated with favourable clinical outcomes. These results have implications for the development of paediatric HIV-1 vaccines. PMID:27403940

  13. Viral Evolution and Cytotoxic T Cell Restricted Selection in Acute Infant HIV-1 Infection

    PubMed Central

    Garcia-Knight, Miguel A.; Slyker, Jennifer; Payne, Barbara Lohman; Pond, Sergei L. Kosakovsky; de Silva, Thushan I.; Chohan, Bhavna; Khasimwa, Brian; Mbori-Ngacha, Dorothy; John-Stewart, Grace; Rowland-Jones, Sarah L.; Esbjörnsson, Joakim

    2016-01-01

    Antiretroviral therapy-naive HIV-1 infected infants experience poor viral containment and rapid disease progression compared to adults. Viral factors (e.g. transmitted cytotoxic T- lymphocyte (CTL) escape mutations) or infant factors (e.g. reduced CTL functional capacity) may explain this observation. We assessed CTL functionality by analysing selection in CTL-targeted HIV-1 epitopes following perinatal infection. HIV-1 gag, pol and nef sequences were generated from a historical repository of longitudinal specimens from 19 vertically infected infants. Evolutionary rate and selection were estimated for each gene and in CTL-restricted and non-restricted epitopes. Evolutionary rate was higher in nef and gag vs. pol, and lower in infants with non-severe immunosuppression vs. severe immunosuppression across gag and nef. Selection pressure was stronger in infants with non-severe immunosuppression vs. severe immunosuppression across gag. The analysis also showed that infants with non-severe immunosuppression had stronger selection in CTL-restricted vs. non-restricted epitopes in gag and nef. Evidence of stronger CTL selection was absent in infants with severe immunosuppression. These data indicate that infant CTLs can exert selection pressure on gag and nef epitopes in early infection and that stronger selection across CTL epitopes is associated with favourable clinical outcomes. These results have implications for the development of paediatric HIV-1 vaccines. PMID:27403940

  14. HIV-1-Specific CD8 T Cells Exhibit Limited Cross-Reactivity during Acute Infection.

    PubMed

    Du, Victor Y; Bansal, Anju; Carlson, Jonathan; Salazar-Gonzalez, Jesus F; Salazar, Maria G; Ladell, Kristin; Gras, Stephanie; Josephs, Tracy M; Heath, Sonya L; Price, David A; Rossjohn, Jamie; Hunter, Eric; Goepfert, Paul A

    2016-04-15

    Prior work has demonstrated that HIV-1-specific CD8 T cells can cross-recognize variant epitopes. However, most of these studies were performed in the context of chronic infection, where the presence of viral quasispecies makes it difficult to ascertain the true nature of the original antigenic stimulus. To overcome this limitation, we evaluated the extent of CD8 T cell cross-reactivity in patients with acute HIV-1 clade B infection. In each case, we determined the transmitted founder virus sequence to identify the autologous epitopes restricted by individual HLA class I molecules. Our data show that cross-reactive CD8 T cells are infrequent during the acute phase of HIV-1 infection. Moreover, in the uncommon instances where cross-reactive responses were detected, the variant epitopes were poorly recognized in cytotoxicity assays. Molecular analysis revealed that similar antigenic structures could be cross-recognized by identical CD8 T cell clonotypes mobilized in vivo, yet even subtle differences in a single TCR-accessible peptide residue were sufficient to disrupt variant-specific reactivity. These findings demonstrate that CD8 T cells are highly specific for autologous epitopes during acute HIV-1 infection. Polyvalent vaccines may therefore be required to provide optimal immune cover against this genetically labile pathogen. PMID:26983786

  15. HIV-1-specific CD8 T cells exhibit limited cross-reactivity during acute infection

    PubMed Central

    Du, Victor Y.; Bansal, Anju; Carlson, Jonathan; Salazar-Gonzalez, Jesus F.; Salazar, Maria G.; Ladell, Kristin; Gras, Stephanie; Josephs, Tracy M.; Heath, Sonya; Price, David A.; Rossjohn, Jamie; Hunter, Eric; Goepfert, Paul A.

    2016-01-01

    Prior work has demonstrated that HIV-1-specific CD8 T cells can cross-recognize variant epitopes. However, the majority of these studies were performed in the context of chronic infection, where the presence of viral quasispecies makes it difficult to ascertain the true nature of the original antigenic stimulus. To overcome this limitation, we evaluated the extent of CD8 T-cell cross-reactivity in patients with acute HIV-1 clade B infection. In each case, we determined the transmitted founder virus sequence to identify the autologous epitopes restricted by individual HLA class I molecules. Our data show that cross-reactive CD8 T cells are infrequent during the acute phase of HIV-1 infection. Moreover, in the uncommon instances where cross-reactive responses were detected, the variant epitopes were poorly recognized in cytotoxicity assays. Molecular analysis revealed that similar antigenic structures could be cross-recognized by identical CD8 T-cell clonotypes mobilized in vivo, yet even subtle differences in a single TCR-accessible peptide residue were sufficient to disrupt variant-specific reactivity. These findings demonstrate that CD8 T cells are highly specific for autologous epitopes during acute HIV-1 infection. Polyvalent vaccines may therefore be required to provide optimal immune cover against this genetically labile pathogen. PMID:26983786

  16. Raman spectroscopy of HIV-1 antigen and antibody

    NASA Astrophysics Data System (ADS)

    Zinin, Pavel V.; Hu, Ningjie; Kamemoto, Lori E.; Yu, Qigui; Misra, Anupam K.; Sharma, Shiv K.

    2011-05-01

    Raman spectra of anti-HIV-1 antibody, HIV-1 antigen (p24), and HIV-1 antibody-antigen complex have been measured in near-infrared and UV regions: 785 nm; 830 nm; and 244 nm laser excitations. The spectrum of the HIV-1 antigen was excited with an infrared laser and contains numerous Raman peaks. The most prominent peaks are broad bands at 1343, 1449, 1609 and 1655 cm-1, which are characteristic of the Raman spectra of biological cells. The UV Raman spectrum of the HIV-1 antigen has a completely different structure. It has two strong peaks at 1613 cm-1 and 1173 cm-1. The peak at 1613 cm-1 is associated with vibrations of the aromatic amino acids tyrosine (Tyr) and tryptophan (Try). The second strongest peak at 1173 cm-1 is associated with the vibration of Tyr. The Raman peak pattern of the HIV-1 antigen-antibody complex is very similar to that of the HIV-1 antigen. The only difference is that the peak at 1007 cm-1 of the Raman spectrum of the HIV-1 antigen-antibody complex is slightly enhanced compared to that of the HIV-1 antigen. This indicates that the peaks of the HIV-1 antigen dominate the Raman spectrum of the HIV-1 antigen-antibody complex.

  17. Short Communication: Neutralizing Antibodies in HIV-1-Infected Brazilian Individuals

    PubMed Central

    Morgado, Mariza Gonçalvez; Côrtes, Fernanda Heloise; Guimarães, Monick Lindermeyer; Mendonça-Lima, Leila; Pilotto, Jose Henrique; Grinsztejn, Beatriz; Veloso, Valdiléa Gonçalves; Bongertz, Vera

    2013-01-01

    Abstract Tests for the detection of the humoral immune response to HIV-1 have to be standardized and established, demanding regional efforts. For this purpose the neutralizing antibody (NAb) assay for HIV-1 in TZM-bl cells was introduced in Brazil. Twenty plasma samples from HIV-1-infected individuals were assayed: 10 progressors and 10 long-term nonprogressors. These were tested against eight env-pseudotyped viruses (psVs) in the TZM-bl NAb assay and against HIV-1 strain HTLV/IIIB (HIV-1 IIIB) in primary lymphocytes. Forty-four percent of the samples showed neutralizing titers for psVs and 55% for HIV-1 IIIB. Plasma from progressors showed a broader neutralization and a higher potency. The introduction of these reference reagents encourages the participation of Brazil in future comparative assessments of anti-HIV-1 antibodies. PMID:23145941

  18. Significant impact of non-B HIV-1 variants genetic diversity in Gabon on plasma HIV-1 RNA quantitation.

    PubMed

    Mouinga-Ondémé, Augustin; Mabika-Mabika, Arsène; Alalade, Patrick; Mongo, Arnaud Delis; Sica, Jeanne; Liégeois, Florian; Rouet, François

    2014-01-01

    Evaluations of HIV-1 RNA viral load assays are lacking in Central Africa. The main objective of our study was to assess the reliability of HIV-1 RNA results obtained with three different assays for samples collected in Gabon. A total of 137 plasma specimens were assessed for HIV-1 RNA using the Abbott RealTime HIV-1® and Nuclisens HIV-1 EasyQ® version 2.0 assays. It included HIV-1 non-B samples (n = 113) representing six subtypes, 10 CRFs and 18 URFs from patients infected with HIV-1 and treated with antiretrovirals that were found HIV-1 RNA positive (≥300 copies/ml) with the Generic HIV viral load® assay; and samples (n = 24) from untreated individuals infected with HIV-1 but showing undetectable (<300 copies/ml) results with the Biocentric kit. For samples found positive with the Generic HIV viral load® test, correlation coefficients obtained between the three techniques were relatively low (R = 0.65 between Generic HIV viral load® and Abbott RealTime HIV-1®, 0.50 between Generic HIV viral load® and Nuclisens HIV-1 EasyQ®, and 0.66 between Abbott RealTime HIV-1® and Nuclisens HIV-1 EasyQ®). Discrepancies by at least one log10 were obtained for 19.6%, 33.7%, and 20% of samples, respectively, irrespective of genotype. Most of samples (22/24) from untreated study patients, found negative with the Biocentric kit, were also found negative with the two other techniques. In Central Africa, HIV-1 genetic diversity remains challenging for viral load testing. Further studies are required in the same area to confirm the presence of HIV-1 strains that are not amplified with at least two different viral load assays.

  19. HIV-1 VACCINES. HIV-1 neutralizing antibodies induced by native-like envelope trimers.

    PubMed

    Sanders, Rogier W; van Gils, Marit J; Derking, Ronald; Sok, Devin; Ketas, Thomas J; Burger, Judith A; Ozorowski, Gabriel; Cupo, Albert; Simonich, Cassandra; Goo, Leslie; Arendt, Heather; Kim, Helen J; Lee, Jeong Hyun; Pugach, Pavel; Williams, Melissa; Debnath, Gargi; Moldt, Brian; van Breemen, Mariëlle J; Isik, Gözde; Medina-Ramírez, Max; Back, Jaap Willem; Koff, Wayne C; Julien, Jean-Philippe; Rakasz, Eva G; Seaman, Michael S; Guttman, Miklos; Lee, Kelly K; Klasse, Per Johan; LaBranche, Celia; Schief, William R; Wilson, Ian A; Overbaugh, Julie; Burton, Dennis R; Ward, Andrew B; Montefiori, David C; Dean, Hansi; Moore, John P

    2015-07-10

    A challenge for HIV-1 immunogen design is the difficulty of inducing neutralizing antibodies (NAbs) against neutralization-resistant (tier 2) viruses that dominate human transmissions. We show that a soluble recombinant HIV-1 envelope glycoprotein trimer that adopts a native conformation, BG505 SOSIP.664, induced NAbs potently against the sequence-matched tier 2 virus in rabbits and similar but weaker responses in macaques. The trimer also consistently induced cross-reactive NAbs against more sensitive (tier 1) viruses. Tier 2 NAbs recognized conformational epitopes that differed between animals and in some cases overlapped with those recognized by broadly neutralizing antibodies (bNAbs), whereas tier 1 responses targeted linear V3 epitopes. A second trimer, B41 SOSIP.664, also induced a strong autologous tier 2 NAb response in rabbits. Thus, native-like trimers represent a promising starting point for the development of HIV-1 vaccines aimed at inducing bNAbs.

  20. Human cytosolic extracts stabilize the HIV-1 core.

    PubMed

    Fricke, Thomas; Brandariz-Nuñez, Alberto; Wang, Xiaozhao; Smith, Amos B; Diaz-Griffero, Felipe

    2013-10-01

    The stability of the HIV-1 core in the cytoplasm is crucial for productive HIV-1 infection. Mutations that stabilize or destabilize the core showed defects on HIV-1 reverse transcription and infection. We developed a novel and simple assay to measure the stability of in vitro-assembled HIV-1 CA-NC complexes. The assay allowed us to demonstrate that cytosolic extracts strongly stabilize the HIV-1 core. Interestingly, stabilization of in vitro-assembled HIV-1 CA-NC complexes is not due solely to macromolecular crowding, suggesting the presence of specific cellular factors that stabilize the HIV-1 core. By using our novel assay, we measured the abilities of different drugs, such as PF74, CAP-1, IXN-053, cyclosporine, Bi2 (also known as BI-2), and the peptide CAI, to modulate the stability of in vitro-assembled HIV-1 CA-NC complexes. Interestingly, we found that PF74 and Bi2 strongly stabilized HIV-1 CA-NC complexes. On the other hand, the peptide CAI destabilized HIV-1 CA-NC complexes. We also found that purified cyclophilin A destabilizes in vitro-assembled HIV-1 CA-NC complexes in the presence of cellular extracts in a cyclosporine-sensitive manner. In agreement with previous observations using the fate-of-the-capsid assay, we also demonstrated the ability of recombinant CPSF6 to stabilize HIV-1 CA-NC complexes. Overall, our findings suggested that cellular extracts specifically stabilize the HIV-1 core. We believe that our assay can be a powerful tool to assess HIV-1 core stability in vitro.

  1. Crystallization studies on HIV-1 reverse transcriptase

    NASA Astrophysics Data System (ADS)

    Lloyd, Lesley F.; Brick, Peter; Blow, David M.; Mei-Zhen, Lou

    1992-08-01

    HIV-1 reverse transcriptase has been crystallized in a variety of forms. Various ligands used for co-crystallization are described and the results presented. All of these crystals showed disorder when examined in the X-ray beam. The best diffraction currently achieved has been approximately 7A˚. The possible reasons for crystal disorder are discussed. An example of another protein, car☐ypeptidase G 2, which initially yielded non-diffracting crystals, is used to illustrate the value of applying random or incomplete factorial screens to sample wider parameter space for conditions to grow well-ordered crystals.

  2. Rigidity analysis of HIV-1 protease

    NASA Astrophysics Data System (ADS)

    Heal, J. W.; Wells, S. A.; Jimenez-Roldan, E.; Freedman, R. F.; Römer, R. A.

    2011-03-01

    We present a rigidity analysis on a large number of X-ray crystal structures of the enzyme HIV-1 protease using the 'pebble game' algorithm of the software FIRST. We find that although the rigidity profile remains similar across a comprehensive set of high resolution structures, the profile changes significantly in the presence of an inhibitor. Our study shows that the action of the inhibitors is to restrict the flexibility of the β-hairpin flaps which allow access to the active site. The results are discussed in the context of full molecular dynamics simulations as well as data from NMR experiments.

  3. Titration of human immunodeficiency virus type 1 (HIV-1) and quantitative analysis of virus expression in vitro using liquid RNA-RNA hybridization.

    PubMed

    Volsky, D J; Pellegrino, M G; Li, G; Logan, K A; Aswell, J E; Lawrence, N P; Decker, S R

    1990-06-01

    An assay is described for titration of human immunodeficiency virus type 1 (HIV-1) and for quantitative analysis of virus expression in vitro. The assay utilizes a liquid RNA-RNA hybridization method coupled with reversible target capture (RTC) on oligo(dT) derivatized magnetic particles. The assay provides a rapid, specific, and sensitive method for quantitation of HIV-1 RNA molecules present either in cells or in viral particles from cell-free culture media. Chronically infected monocytoid U1.1 cells were found to carry 52 pg HIV-1 RNA per 200,000 cells (160 HIV-1 RNA molecules per cell). In contrast, acutely infected CEM and H9 cells carried 3010 and 4370 pg HIV-1 RNA per 200,000 cells (9040 and 13,110 HIV-1 RNA molecules per cell, respectively). No hybridization was observed with uninfected cells or cells infected with HIV-2, HTLV-I, HTLV-II, or EBV. Use of liquid HIV-1 RNA hybridization in association with HIV-1 protein detection methods permits more complete characterization of HIV-1 expression in host cells than either method alone, and also provides a method for standardizing preparations of virus.

  4. Optically transmitted and inductively coupled electric reference to access in vivo concentrations for quantitative proton-decoupled ¹³C magnetic resonance spectroscopy.

    PubMed

    Chen, Xing; Pavan, Matteo; Heinzer-Schweizer, Susanne; Boesiger, Peter; Henning, Anke

    2012-01-01

    This report describes our efforts on quantification of tissue metabolite concentrations in mM by nuclear Overhauser enhanced and proton decoupled (13) C magnetic resonance spectroscopy and the Electric Reference To access In vivo Concentrations (ERETIC) method. Previous work showed that a calibrated synthetic magnetic resonance spectroscopy-like signal transmitted through an optical fiber and inductively coupled into a transmit/receive coil represents a reliable reference standard for in vivo (1) H magnetic resonance spectroscopy quantification on a clinical platform. In this work, we introduce a related implementation that enables simultaneous proton decoupling and ERETIC-based metabolite quantification and hence extends the applicability of the ERETIC method to nuclear Overhauser enhanced and proton decoupled in vivo (13) C magnetic resonance spectroscopy. In addition, ERETIC signal stability under the influence of simultaneous proton decoupling is investigated. The proposed quantification method was cross-validated against internal and external reference standards on human skeletal muscle. The ERETIC signal intensity stability was 100.65 ± 4.18% over 3 months including measurements with and without proton decoupling. Glycogen and unsaturated fatty acid concentrations measured with the ERETIC method were in excellent agreement with internal creatine and external phantom reference methods, showing a difference of 1.85 ± 1.21% for glycogen and 1.84 ± 1.00% for unsaturated fatty acid between ERETIC and creatine-based quantification, whereas the deviations between external reference and creatine-based quantification are 6.95 ± 9.52% and 3.19 ± 2.60%, respectively.

  5. High Degree of HIV-1 Group M (HIV-1M) Genetic Diversity within Circulating Recombinant Forms: Insight into the Early Events of HIV-1M Evolution

    PubMed Central

    2015-01-01

    ABSTRACT The existence of various highly divergent HIV-1 lineages and of recombination-derived sequence tracts of indeterminate origin within established circulating recombinant forms (CRFs) strongly suggests that HIV-1 group M (HIV-1M) diversity is not fully represented under the current classification system. Here we used a fully exploratory screen for recombination on a set of 480 near-full-length genomes representing the full known diversity of HIV-1M. We decomposed recombinant sequences into their constituent parts and then used maximum-likelihood phylogenetic analyses of this mostly recombination-free data set to identify rare divergent sequence lineages that fall outside the major named HIV-1M taxonomic groupings. We found that many of the sequence fragments occurring within CRFs (including CRF04_cpx, CRF06_cpx, CRF11_cpx, CRF18_cpx, CRF25_cpx, CRF27_cpx, and CRF49_cpx) are in fact likely derived from divergent unclassified parental lineages that may predate the current subtypes, even though they are presently identified as derived from currently defined HIV-1M subtypes. Our evidence suggests that some of these CRFs are descended predominantly from what were or are major previously unidentified HIV-1M lineages that were likely epidemiologically relevant during the early stages of the HIV-1M epidemic. The restriction of these divergent lineages to the Congo basin suggests that they were less infectious and/or simply not present at the time and place of the initial migratory wave that triggered the global epidemic. IMPORTANCE HIV-1 group M (HIV-1M) likely spread to the rest of the world from the Congo basin in the mid-1900s (N. R. Faria et al., Science 346:56–61, 2014, http://dx.doi.org/10.1126/science.1256739) and is today the principal cause of the AIDS pandemic. Here, we show that large sequence fragments from several HIV-1M circulating recombinant forms (CRFs) are derived from divergent parental lineages that cannot reasonably be classified within the

  6. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic.

    PubMed

    Junqueira, Dennis Maletich; de Medeiros, Rubia Marília; Gräf, Tiago; Almeida, Sabrina Esteves de Matos

    2016-01-01

    The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B) epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989-2013). Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48-3.30) to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups.

  7. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic

    PubMed Central

    Junqueira, Dennis Maletich; de Medeiros, Rubia Marília; Gräf, Tiago; Almeida, Sabrina Esteves de Matos

    2016-01-01

    The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B) epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989–2013). Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48–3.30) to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups. PMID:27258369

  8. The evolution of HIV-1 interactions with coreceptors and mannose C-type lectin receptors.

    PubMed

    Borggren, Marie; Jansson, Marianne

    2015-01-01

    The phenotype of human immunodeficiency virus type 1 (HIV-1) commonly evolves between and within infected individuals, at virus transmission, and during disease progression. This evolution includes altered interactions between the virus and its coreceptors, i.e., chemokine receptors, as well as mannose C-type lectin receptors (CLRs). Transmitted/founder viruses are predominantly restricted to CCR5, whereas the subsequent intrapatient evolution of HIV-1 coreceptor use during progressive disease can be subdivided into two distinct pathways. Accordingly, the CCR5-restricted virus population is either gradually replaced by virus variants able to use CXCR4 or evolves toward an altered, more flexible use of CCR5. Despite a strong dependency on these coreceptors for host cell entry, HIV-1 also interacts with other cell surface molecules during target cell attachment, including the CLRs. The virus interaction with the CLRs may result either in the efficient transfer of virus to CD4(+) T cells or in the degradation of the virus in endosomal compartments. The determinants of the diverse outcomes depend on which CLR is engaged and also on the glycan makeup of the envelope glycoproteins, which may evolve with the strength of the immune pressure during the disease course. With the current clinical introduction of CCR5 antagonists and the development of additional entry inhibitors, knowledge on the evolution and baseline characteristics of HIV-1 interactions with coreceptor and CLR interactions may play important roles for individualized and optimized treatment strategies. This review summarizes our current understanding of the evolution of HIV-1 interactions with these receptors. PMID:25595802

  9. Fucoidans as Potential Inhibitors of HIV-1

    PubMed Central

    Prokofjeva, Maria M.; Imbs, Tatyana I.; Shevchenko, Natalya M.; Spirin, Pavel V.; Horn, Stefan; Fehse, Boris; Zvyagintseva, Tatyana N.; Prassolov, Vladimir S.

    2013-01-01

    The antiviral activity of different structure fucoidans (α-l-fucans and galactofucans) was studied using two model viral systems based on a lentiviral vectors and a replication competent Moloney murine leukemia virus (Mo-MuLV). It was found that investigated fucoidans have no cytotoxic effects on Jurkat and SC-1cell at the concentration range of 0.001–100 µg/mL. Fucoidans with different efficiency suppressed transduction of Jurkat cell line by pseudo-HIV-1 particles carrying the envelope protein of HIV-1 and infection of SC-1 cells by Mo-MuLV. According to our data, all natural fucoidans can be considered as potential anti-HIV agents regardless of their carbohydrate backbone and degree of sulfating, since their activity is shown at low concentrations (0.001–0.05 µg/mL). High molecular weight fucoidans isolated from Saccharina cichorioides (1.3-α-l-fucan), and S. japonica (galactofucan) were the most effective inhibitors. PMID:23966033

  10. Fucoidans as potential inhibitors of HIV-1.

    PubMed

    Prokofjeva, Maria M; Imbs, Tatyana I; Shevchenko, Natalya M; Spirin, Pavel V; Horn, Stefan; Fehse, Boris; Zvyagintseva, Tatyana N; Prassolov, Vladimir S

    2013-08-19

    The antiviral activity of different structure fucoidans (α-l-fucans and galactofucans) was studied using two model viral systems based on a lentiviral vectors and a replication competent Moloney murine leukemia virus (Mo-MuLV). It was found that investigated fucoidans have no cytotoxic effects on Jurkat and SC-1cell at the concentration range of 0.001-100 µg/mL. Fucoidans with different efficiency suppressed transduction of Jurkat cell line by pseudo-HIV-1 particles carrying the envelope protein of HIV-1 and infection of SC-1 cells by Mo-MuLV. According to our data, all natural fucoidans can be considered as potential anti-HIV agents regardless of their carbohydrate backbone and degree of sulfating, since their activity is shown at low concentrations (0.001-0.05 µg/mL). High molecular weight fucoidans isolated from Saccharina cichorioides (1.3-α-l-fucan), and S. japonica (galactofucan) were the most effective inhibitors.

  11. Interactions of HIV-1 and HIV-2 envelope glycoproteins with sulphated polysaccharides and mannose-6-phosphate.

    PubMed

    Mbemba, E; Gluckman, J C; Gattegno, L

    1994-02-01

    Envelope glycoproteins of human immunodeficiency viruses (HIV-1 and HIV-2) can interact with high-mannose glycans and with the mannosyl or N-acetylglucosaminyl core of complex-type oligosaccharidic structures. HIV-1 glycoproteins also specifically bind sulphated polysaccharides such as dextran sulphate (DS) and heparin. Here, we show that the latter property is shared by HIV-2 recombinant gp140 (rgp140) precursor glycoprotein. Binding of rgp140 and of corresponding rgp160 of HIV-1 to heparin- and DS-substituted (sulphated dextran beads; SDB) affinity matrices was inhibited by the soluble specific ligand and also by fetuin, asialofetuin or the anionic simple carbohydrate derivative mannose-6-phosphate (M6P). Interaction of HIV-1 rgp120 subunit with the two affinity matrices was also inhibited by M6P, but only rgp120 binding to heparin-agarose, and not that to SDB, was affected by fetuin and asialofetuin. These results suggest that HIV-1 and HIV-2 envelope glycoproteins presumably display different sulphated polysaccharide and carbohydrate recognition sites. Some of these may be common or in close proximity: with respect to rgp160, for example, the sites may be common on the gp41 moiety and/or in a region of gp120 which would be more accessible when expressed on rgp160 than on processed gp120, while they may be distinct on the cleaved gp120 subunit. Finally, because M6P is a marker of lysosomal enzymes, we verified that HIV-1 and HIV-2 envelope glycoproteins could specifically bind in a M6P-inhibitable manner to a representative lysosomal enzyme, bovine liver beta-glucuronidase coupled to agarose, suggesting that they may possibly interfere with lysosomal enzyme sorting in HIV-infected cells.

  12. Evaluation of Hologic Aptima HIV-1 Quant Dx Assay on the Panther System on HIV Subtypes.

    PubMed

    Manak, Mark M; Hack, Holly R; Nair, Sangeetha V; Worlock, Andrew; Malia, Jennifer A; Peel, Sheila A; Jagodzinski, Linda L

    2016-10-01

    Quantitation of the HIV-1 viral load in plasma is the current standard of care for clinical monitoring of HIV-infected individuals undergoing antiretroviral therapy. This study evaluated the analytical and clinical performances of the Aptima HIV-1 Quant Dx assay (Hologic, San Diego, CA) for monitoring viral load by using 277 well-characterized subtype samples, including 171 cultured virus isolates and 106 plasma samples from 35 countries, representing all major HIV subtypes, recombinants, and circulating recombinant forms (CRFs) currently in circulation worldwide. Linearity of the Aptima assay was tested on each of 6 major HIV-1 subtypes (A, B, C, D, CRF01_AE, and CRF02_AG) and demonstrated an R(2) value of ≥0.996. The performance of the Aptima assay was also compared to those of the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 v.2 (CAP/CTM) and Abbott m2000 RealTime HIV-1 (RealTime) assays on all subtype samples. The Aptima assay values averaged 0.21 log higher than the CAP/CTM values and 0.30 log higher than the RealTime values, and the values were >0.4 log higher than CAP/CTM values for subtypes F and G and than RealTime values for subtypes C, F, and G and CRF02_AG. Two samples demonstrated results with >1-log differences from RealTime results. When the data were adjusted by the average difference, 94.9% and 87.0% of Aptima results fell within 0.5 log of the CAP/CTM and RealTime results, respectively. The linearity and accuracy of the Aptima assay in correctly quantitating all major HIV-1 subtypes, coupled with the completely automated format and high throughput of the Panther system, make this system well suited for reliable measurement of viral load in the clinical laboratory. PMID:27510829

  13. Evaluation of Hologic Aptima HIV-1 Quant Dx Assay on the Panther System on HIV Subtypes.

    PubMed

    Manak, Mark M; Hack, Holly R; Nair, Sangeetha V; Worlock, Andrew; Malia, Jennifer A; Peel, Sheila A; Jagodzinski, Linda L

    2016-10-01

    Quantitation of the HIV-1 viral load in plasma is the current standard of care for clinical monitoring of HIV-infected individuals undergoing antiretroviral therapy. This study evaluated the analytical and clinical performances of the Aptima HIV-1 Quant Dx assay (Hologic, San Diego, CA) for monitoring viral load by using 277 well-characterized subtype samples, including 171 cultured virus isolates and 106 plasma samples from 35 countries, representing all major HIV subtypes, recombinants, and circulating recombinant forms (CRFs) currently in circulation worldwide. Linearity of the Aptima assay was tested on each of 6 major HIV-1 subtypes (A, B, C, D, CRF01_AE, and CRF02_AG) and demonstrated an R(2) value of ≥0.996. The performance of the Aptima assay was also compared to those of the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 v.2 (CAP/CTM) and Abbott m2000 RealTime HIV-1 (RealTime) assays on all subtype samples. The Aptima assay values averaged 0.21 log higher than the CAP/CTM values and 0.30 log higher than the RealTime values, and the values were >0.4 log higher than CAP/CTM values for subtypes F and G and than RealTime values for subtypes C, F, and G and CRF02_AG. Two samples demonstrated results with >1-log differences from RealTime results. When the data were adjusted by the average difference, 94.9% and 87.0% of Aptima results fell within 0.5 log of the CAP/CTM and RealTime results, respectively. The linearity and accuracy of the Aptima assay in correctly quantitating all major HIV-1 subtypes, coupled with the completely automated format and high throughput of the Panther system, make this system well suited for reliable measurement of viral load in the clinical laboratory.

  14. Purinergic Receptors: Key Mediators of HIV-1 Infection and Inflammation

    PubMed Central

    Swartz, Talia H.; Dubyak, George R.; Chen, Benjamin K.

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) causes a chronic infection that afflicts more than 30 million individuals worldwide. While the infection can be suppressed with potent antiretroviral therapies, individuals infected with HIV-1 have elevated levels of inflammation as indicated by increased T cell activation, soluble biomarkers, and associated morbidity and mortality. A single mechanism linking HIV-1 pathogenesis to this inflammation has yet to be identified. Purinergic receptors are known to mediate inflammation and have been shown to be required for HIV-1 infection at the level of HIV-1 membrane fusion. Here, we review the literature on the role of purinergic receptors in HIV-1 infection and associated inflammation and describe a role for these receptors as potential therapeutic targets. PMID:26635799

  15. TGFβ Induces a SAMHD1-Independent Post-Entry Restriction to HIV-1 Infection of Human Epithelial Langerhans Cells.

    PubMed

    Czubala, Magdalena A; Finsterbusch, Katja; Ivory, Matthew O; Mitchell, J Paul; Ahmed, Zahra; Shimauchi, Takatoshi; Karoo, Richard O S; Coulman, Sion A; Gateley, Christopher; Birchall, James C; Blanchet, Fabien P; Piguet, Vincent

    2016-10-01

    Sterile alpha motif (SAM) and histidine-aspartic (HD) domains protein 1 (SAMHD1) was previously identified as a critical post-entry restriction factor to HIV-1 infection in myeloid dendritic cells. Here we show that SAMHD1 is also expressed in epidermis-isolated Langerhans cells (LC), but degradation of SAMHD1 does not rescue HIV-1 or vesicular stomatitis virus G-pseudotyped lentivectors infection in LC. Strikingly, using Langerhans cells model systems (mutz-3-derived LC, monocyte-derived LC [MDLC], and freshly isolated epidermal LC), we characterize previously unreported post-entry restriction activity to HIV-1 in these cells, which acts at HIV-1 reverse transcription, but remains independent of restriction factors SAMHD1 and myxovirus resistance 2 (MX2). We demonstrate that transforming growth factor-β signaling confers this potent HIV-1 restriction in MDLC during their differentiation and blocking of mothers against decapentaplegic homolog 2 (SMAD2) signaling in MDLC restores cells' infectivity. Interestingly, maturation of MDLC with a toll-like receptor 2 agonist or transforming growth factor-α significantly increases cells' susceptibility to HIV-1 infection, which may explain why HIV-1 acquisition is increased during coinfection with sexually transmitted infections. In conclusion, we report a SAMHD1-independent post-entry restriction in MDLC and LC isolated from epidermis, which inhibits HIV-1 replication. A better understanding of HIV-1 restriction and propagation from LC to CD4(+) T cells may help in the development of new microbicides or vaccines to curb HIV-1 infection at its earliest stages during mucosal transmission. PMID:27375111

  16. [Inhibitory effect of human saliva on HIV-1 infectivity].

    PubMed

    Etsuko, K; Wei, S

    2001-08-01

    Human saliva is known to decrease human immunodeficiency virus type 1 (HIV-1) infectivity in vitro. The purpose of this study was to confirm these findings and to explore the mechanism of action of saliva. Whole saliva from seronegative donors was incubated with HIV-1IIIB chronically infected MOLT 4 cells (MOLT 4/HIV-1IIIB cells) or cell-free HIV-1IIIB or KMT strains. We monitored viral infectivity by using MAGI/CCR5 cells. Whole saliva with Na levels less than 20 mEq/l rapidly damaged MOLT 4/HIV-1IIIB cells, thereby HIV infection to MAGI/CCR5 cells by MOLT 4/HIV-1IIIB cells was nearly abolished. On the contrary, in the cace of whole saliva with Na levels more than 23 mEq/l which damaged few cells, cell-to-cell transmission of HIV-1IIIB was prevented by more than 50%. The infectivity of cell-free HIV-1IIIB to MAGI/CCR5 cells was abolished after incubating and filtering the HIV with whole saliva. Depletion of secretory leukocyte protease inhibitor (SLPI) from whole saliva resulted in a 11-28% decrease in the anti HIV-1KMT activity of saliva. Preincubation of host cells with whole saliva led to an enhancement of the HIV infection rather than inhibition. Whole saliva had no effect on the expression level of the cellular receptors (CD4, CXCR4 and CCR5). These results suggest that the inhibitory effect of whole saliva on HIV-1 infectivity is directly linked to the virus itself rather than on the host cell. Moreover, the physical entrapment of cell-free HIV-1 by whole saliva seems to have major salivaly defence mechanisms against HIV-1 infection through the oral cavity. PMID:16578966

  17. Raltegravir, an HIV-1 integrase inhibitor for HIV infection.

    PubMed

    Cabrera, Cecilia

    2008-08-01

    Merck & Co has developed and launched raltegravir, an HIV-1 integrase inhibitor for the treatment of HIV-1 infection in treatment-experienced adult patients who have evidence of viral replication and HIV-1 strains resistant to multiple antiretroviral agents. This drug is the lead from a series of integrase strand transfer inhibitors and, by April 2008, it had been launched in Canada, the US, the UK, France, Germany and Spain, and had been filed for approval in Japan.

  18. Disseminated human immunodeficiency virus 1 (HIV-1) infection in SCID- hu mice after peripheral inoculation with HIV-1

    PubMed Central

    1994-01-01

    A small animal model that could be infected with human immunodeficiency virus 1 (HIV-1) after peripheral inoculation would greatly facilitate the study of the pathophysiology of acute HIV-1 infection. The utility of SCID mice implanted with human fetal thymus and liver (SCID-hu mice) for studying peripheral HIV-1 infection in vivo has been hampered by the requirement for direct intraimplant injection of HIV-1 and the continued restriction of the resultant HIV-1 infection to the human thymus and liver (hu-thy/liv) implant. This may have been due to the very low numbers of human T cells present in the SCID-hu mouse peripheral lymphoid compartment. Since the degree of the peripheral reconstitution of SCID-hu mice with human T cells may be a function of the hu-thy/liv implant size, we increased the quantity of hu-thy/liv tissue implanted under the renal capsule and implanted hu-thy/liv tissue under the capsules of both kidneys. This resulted in SCID-hu mice in which significant numbers of human T cells were detected in the peripheral blood, spleens, and lymph nodes. After intraimplant injection of HIV-1 into these modified SCID-hu mice, significant HIV-1 infection was detected by quantitative coculture not only in the hu- thy/liv implant, but also in the spleen and peripheral blood. This indicated that HIV-1 infection can spread from the thymus to the peripheral lymphoid compartment. More importantly, a similar degree of infection of the hu-thy/liv implant and peripheral lymphoid compartment occurred after peripheral intraperitoneal inoculation with HIV-1. Active viral replication was indicated by the detection of HIV-1 gag DNA, HIV-1 gag RNA, and spliced tat/rev RNA in the hu-thy/liv implants, peripheral blood mononuclear cells (PBMC), spleens, and lymph nodes of these HIV-1-infected SCID-hu mice. As a first step in using our modified SCID-hu mouse model to investigate the pathophysiological consequences of HIV-1 infection, the effect of HIV-1 infection on the

  19. Structured treatment interruptions to control HIV-1 infection.

    PubMed

    Lori, F; Maserati, R; Foli, A; Seminari, E; Timpone, J; Lisziewicz, J

    2000-01-22

    Structured treatment interruptions progressively lowered the rate of viral rebound in some HIV-1 infected patients. This approach should be explored as an alternative to continuous antiretroviral therapies.

  20. Broad activation of latent HIV-1 in vivo.

    PubMed

    Barton, Kirston; Hiener, Bonnie; Winckelmann, Anni; Rasmussen, Thomas Aagaard; Shao, Wei; Byth, Karen; Lanfear, Robert; Solomon, Ajantha; McMahon, James; Harrington, Sean; Buzon, Maria; Lichterfeld, Mathias; Denton, Paul W; Olesen, Rikke; Østergaard, Lars; Tolstrup, Martin; Lewin, Sharon R; Søgaard, Ole Schmeltz; Palmer, Sarah

    2016-01-01

    The 'shock and kill' approach to cure human immunodeficiency virus (HIV) includes transcriptional induction of latent HIV-1 proviruses using latency-reversing agents (LRAs) with targeted immunotherapy to purge infected cells. The administration of LRAs (panobinostat or vorinostat) to HIV-1-infected individuals on antiretroviral therapy induces a significant increase in cell-associated unspliced (CA-US) HIV-1 RNA from CD4(+) T cells. However, it is important to discern whether the increases in CA-US HIV-1 RNA are due to limited or broad activation of HIV-1 proviruses. Here we use single-genome sequencing to find that the RNA transcripts observed following LRA administration are genetically diverse, indicating activation of transcription from an extensive range of proviruses. Defective sequences are more frequently found in CA HIV-1 RNA than in HIV-1 DNA, which has implications for developing an accurate measure of HIV-1 reservoir size. Our findings provide insights into the effects of panobinostat and vorinostat as LRAs for latent HIV-1. PMID:27605062

  1. Impaired IL-2 expression in latent HIV-1 infection.

    PubMed

    Shin, YoungHyun; Yoon, Cheol-Hee; Lim, Hoyong; Park, Jihwan; Roh, Tae-Young; Kang, Chun; Choi, Byeong-Sun

    2015-08-01

    Regarding the T cell function in HIV-1 infection, activation of T cells is enhanced in acutely HIV-1-infected T cells upon stimuli. However, T cell immune responses underlying the activation of T cell receptor (TCR) signaling molecules and interleukin (IL)-2 production in latently HIV-1-infected cells are poorly understood. The expression and activation of TCR components and its downstream molecules in acutely and latently HIV-1-infected T cells were compared using quantitative reverse transcription polymerase chain reaction (RT-PCR) for mRNA expression and enzyme-linked immunosorbent assay (ELISA) for levels of IL-2 in phytohemagglutinin M (PHA-M). The levels of T cell surface molecules and TCR signaling molecules in latently HIV-1-infected cells were greatly decreased without changes in their mRNA levels. In addition, downstream TCR-signaling molecules in latently HIV-1-infected cells were not activated even in the presence of PHA-M. The phosphorylation of mitogen-activated protein kinases (MAPKs) in the presence of PHA-M was weakly induced in latently HIV-1-infected cells but was greater in acutely HIVNL4-3-infected cells. Finally, the production of IL-2 was significantly decreased in latently HIV-1-infected cells compared with uninfected parent cells. Thus, IL-2-related immunological functions in latently HIV-1-infected T cells were markedly impaired even in the presence of stimuli.

  2. Broad activation of latent HIV-1 in vivo

    PubMed Central

    Barton, Kirston; Hiener, Bonnie; Winckelmann, Anni; Rasmussen, Thomas Aagaard; Shao, Wei; Byth, Karen; Lanfear, Robert; Solomon, Ajantha; McMahon, James; Harrington, Sean; Buzon, Maria; Lichterfeld, Mathias; Denton, Paul W.; Olesen, Rikke; Østergaard, Lars; Tolstrup, Martin; Lewin, Sharon R.; Søgaard, Ole Schmeltz; Palmer, Sarah

    2016-01-01

    The ‘shock and kill' approach to cure human immunodeficiency virus (HIV) includes transcriptional induction of latent HIV-1 proviruses using latency-reversing agents (LRAs) with targeted immunotherapy to purge infected cells. The administration of LRAs (panobinostat or vorinostat) to HIV-1-infected individuals on antiretroviral therapy induces a significant increase in cell-associated unspliced (CA-US) HIV-1 RNA from CD4+ T cells. However, it is important to discern whether the increases in CA-US HIV-1 RNA are due to limited or broad activation of HIV-1 proviruses. Here we use single-genome sequencing to find that the RNA transcripts observed following LRA administration are genetically diverse, indicating activation of transcription from an extensive range of proviruses. Defective sequences are more frequently found in CA HIV-1 RNA than in HIV-1 DNA, which has implications for developing an accurate measure of HIV-1 reservoir size. Our findings provide insights into the effects of panobinostat and vorinostat as LRAs for latent HIV-1. PMID:27605062

  3. Detection of diverse HIV-1 genetic subtypes in the USA.

    PubMed

    Brodine, S K; Mascola, J R; Weiss, P J; Ito, S I; Porter, K R; Artenstein, A W; Garland, F C; McCutchan, F E; Burke, D S

    1995-11-01

    Of the nine genetic subtypes of HIV-1 that exist world wide, subtype B predominates in North America and Europe. Thus, most knowledge about HIV-1 and most vaccine development efforts are based on subtype B viruses. We document here the detection of HIV-1 subtypes A, D, and E in five US servicemen who acquired these non-subtype-B infections during overseas deployments. The dispersal of diverse HIV-1 subtypes into regions of the world with previously restricted genetic diversity may have important implications for the epidemiology of the epidemic and for the design and implementation of vaccine trials. PMID:7475661

  4. [Effective components against HIV-1 replicative enzymes isolated from plants].

    PubMed

    Peng, Zong-gen; Xu, Li-jia; Ye, Wen-cai; Xiao, Pei-gen; Chen, Hong-shan

    2010-02-01

    Plant active components characterized of many different structures and activities on multiple targets, have made them to be the important sources of inhibitors on HIV-1. For finding leading compounds with new structure against HIV-1, three key HIV-1 replicative enzymes (reverse transcriptase, protease and integrase) were used as screening models. The in vitro activities of 45 plant derived components isolated from Schisandraceae, Rutaceae and Ranunculaceae were reported. Within twelve triterpene components isolated, eight compounds were found to inhibit HIV-1 protease, in these eight active compounds, kadsuranic acid A (7) and nigranoic acid (8), inhibited both HIV-1 protease and integrase; Among fifteen lignans, meso-dihydroguaiaretic acid (15) and kadsurarin (16) were active on HIV-1 reverse transcriptase, and 4, 4-di(4-hydroxy-3-methoxyphenly)-2, 3-dimethylbutanol (13) active on HIV-1 integrase. All of the six alkaloids, seven flavones, and five others compounds were not active or only with low activities against HIV-1 replicative enzymes. Further studies of the triterpene components showing strong inhibitory activities on HIV-1 were warranted.

  5. Genome editing strategies: potential tools for eradicating HIV-1/AIDS

    PubMed Central

    Khalili, Kamel; Gordon, Jennifer; Cosentino, Laura; Hu, Wenhui

    2015-01-01

    Current therapy for controlling HIV-1 infection and preventing AIDS progression has profoundly decreased viral replication in cells susceptible to HIV-1 infection, but it does not eliminate the low level of viral replication in latently infected cells which contain integrated copies of HIV-1 proviral DNA. There is an urgent need for the development of HIV-1 genome eradication strategies that will lead to a permanent or “sterile” cure of HIV-1/AIDS. In the past few years, novel nuclease-initiated genome editing tools have been developing rapidly, including ZFNs, TALENs, and the CRISPR/Cas9 system. These surgical knives, which can excise any genome, provide a great opportunity to eradicate the HIV-1 genome by targeting highly conserved regions of the HIV-1 long terminal repeats or essential viral genes. Given the time consuming and costly engineering of target-specific ZFNs and TALENs, the RNA-guided endonuclease Cas9 technology has emerged as a simpler and more versatile technology to allow permanent removal of integrated HIV-1 proviral DNA in eukaryotic cells, and hopefully animal models or human patients. The major unmet challenges of this approach at present include inefficient nuclease gene delivery, potential off-target cleavage, and cell-specific genome targeting. Nanoparticle or lentivirus-mediated delivery of next generation Cas9 technologies including nickase or RNA-guided FokI nuclease (RFN) will further improve the potential for genome editing to become a promising approach for curing HIV-1/AIDS. PMID:25716921

  6. Broad activation of latent HIV-1 in vivo.

    PubMed

    Barton, Kirston; Hiener, Bonnie; Winckelmann, Anni; Rasmussen, Thomas Aagaard; Shao, Wei; Byth, Karen; Lanfear, Robert; Solomon, Ajantha; McMahon, James; Harrington, Sean; Buzon, Maria; Lichterfeld, Mathias; Denton, Paul W; Olesen, Rikke; Østergaard, Lars; Tolstrup, Martin; Lewin, Sharon R; Søgaard, Ole Schmeltz; Palmer, Sarah

    2016-09-08

    The 'shock and kill' approach to cure human immunodeficiency virus (HIV) includes transcriptional induction of latent HIV-1 proviruses using latency-reversing agents (LRAs) with targeted immunotherapy to purge infected cells. The administration of LRAs (panobinostat or vorinostat) to HIV-1-infected individuals on antiretroviral therapy induces a significant increase in cell-associated unspliced (CA-US) HIV-1 RNA from CD4(+) T cells. However, it is important to discern whether the increases in CA-US HIV-1 RNA are due to limited or broad activation of HIV-1 proviruses. Here we use single-genome sequencing to find that the RNA transcripts observed following LRA administration are genetically diverse, indicating activation of transcription from an extensive range of proviruses. Defective sequences are more frequently found in CA HIV-1 RNA than in HIV-1 DNA, which has implications for developing an accurate measure of HIV-1 reservoir size. Our findings provide insights into the effects of panobinostat and vorinostat as LRAs for latent HIV-1.

  7. Platelets and HIV-1 infection: old and new aspects.

    PubMed

    Torre, Donato; Pugliese, Agostino

    2008-09-01

    In this review we summarize the data on interaction of platelets with HIV-1 infection. Thrombocytopenia is a common finding among HIV-1 infected patients; several combined factors contribute to low peripheral platelet counts, which are present during all the stages of the disease. In addition, a relationship between platelet count, plasma viral load and disease progression has been reported, and this shows the potential influence platelets may have on the natural history of HIV-1 disease. Several lines of evidence have shown that platelets are an integral part of inflammation, and can be also potent effector cells of innate immune response as well as of adaptive immunity. Thus, we rewieved the role of inflammatory cytokines, and chemokines as activators of platelets during HIV-1 infection. Moreover, platelets show a direct interaction with HIV-1 itself, through different pathogenic mechanisms as binding, engulfment, internalisation of HIV-1, playing a role in host defence during HIV-1 infection, by limiting viral spread and probably by inactivating viral particles. Platelets may also play an intriguing role on endothelial dysfunction present in HIV-1 infection, and this topic begins to receive systematic study, inasmuch as interaction between platelets and endothelial cells is important in the pathogenesis of atherosclerosis in HIV-1 infected patients, especially in those patients treated with antiretroviral drugs. Finally, this review attempts to better define the state of this emerging issue, to focus areas of potential clinical relevance, and to suggest several directions for future research.

  8. Characteristics of Women Enrolled into a Randomized Clinical Trial of Dapivirine Vaginal Ring for HIV-1 Prevention

    PubMed Central

    Palanee-Phillips, Thesla; Schwartz, Katie; Brown, Elizabeth R.; Govender, Vaneshree; Mgodi, Nyaradzo; Kiweewa, Flavia Matovu; Nair, Gonasagrie; Mhlanga, Felix; Siva, Samantha; Bekker, Linda-Gail; Jeenarain, Nitesha; Gaffoor, Zakir; Martinson, Francis; Makanani, Bonus; Naidoo, Sarita; Pather, Arendevi; Phillip, Jessica; Husnik, Marla J.; van der Straten, Ariane; Soto-Torres, Lydia; Baeten, Jared

    2015-01-01

    Introduction Women in sub-Saharan Africa are a priority population for evaluation of new biomedical HIV-1 prevention strategies. Antiretroviral pre-exposure prophylaxis is a promising prevention approach; however, clinical trials among young women using daily or coitally-dependent products have found low adherence. Antiretroviral-containing vaginal microbicide rings, which release medication over a month or longer, may reduce these adherence challenges. Methods ASPIRE (A Study to Prevent Infection with a Ring for Extended Use) is a phase III, randomized, double-blind, placebo-controlled trial testing the safety and effectiveness of a vaginal ring containing the non-nucleoside reverse transcriptase inhibitor dapivirine for prevention of HIV-1 infection. We describe the baseline characteristics of African women enrolled in the ASPIRE trial. Results Between August 2012 and June 2014, 5516 women were screened and 2629 HIV-1 seronegative women between 18–45 years of age were enrolled from 15 research sites in Malawi, South Africa, Uganda, and Zimbabwe. The median age was 26 years (IQR 22–31) and the majority (59%) were unmarried. Nearly 100% of participants reported having a primary sex partner in the prior three months but 43% did not know the HIV-1 status of their primary partner; 17% reported additional concurrent partners. Nearly two-thirds (64%) reported having disclosed to primary partners about planned vaginal ring use in the trial. Sexually transmitted infections were prevalent: 12% had Chlamydia trachomatis, 7% Trichomonas vaginalis, 4% Neisseria gonorrhoeae, and 1% syphilis. Conclusions African HIV-1 seronegative women at risk of HIV -1 infection were successfully enrolled into a phase III trial of dapivirine vaginal ring for HIV-1 prevention. PMID:26061040

  9. Transcriptional Bursting from the HIV-1 Promoter is a Significant Source of Stochastic Noise in HIV-1 Gene Expression

    SciTech Connect

    Singh, A; Razooky, B; Cox, Chris D.; Simpson, Michael L; Weinberger, Leor S.

    2010-01-01

    Analysis of noise in gene expression has proven a powerful approach for analyzing gene regulatory architecture. To probe the regulatory mechanisms controlling expression of HIV-1, we analyze noise in gene-expression from HIV-1 s long terminal repeat (LTR) promoter at different HIV-1 integration sites across the human genome. Flow cytometry analysis of GFP expression from the HIV-1 LTR shows high variability (noise) at each integration site. Notably, the measured noise levels are inconsistent with constitutive gene expression models. Instead, quantification of expression noise indicates that HIV-1 gene expression occurs through randomly timed bursts of activity from the LTR and that each burst generates an average of 2 10 mRNA transcripts before the promoter returns to an inactive state. These data indicate that transcriptional bursting can generate high variability in HIV-1 early gene products, which may critically influence the viral fate-decision between active replication and proviral latency.

  10. Prevalence of HIV-1 Subtypes and Drug Resistance-Associated Mutations in HIV-1-Positive Treatment-Naive Pregnant Women in Pointe Noire, Republic of the Congo (Kento-Mwana Project).

    PubMed

    Bruzzone, Bianca; Saladini, Francesco; Sticchi, Laura; Mayinda Mboungou, Franc A; Barresi, Renata; Caligiuri, Patrizia; Calzi, Anna; Zazzi, Maurizio; Icardi, Giancarlo; Viscoli, Claudio; Bisio, Francesca

    2015-08-01

    The Kento-Mwana project was carried out in Pointe Noire, Republic of the Congo, to prevent mother-to-child HIV-1 transmission. To determine the prevalence of different subtypes and transmitted drug resistance-associated mutations, 95 plasma samples were collected at baseline from HIV-1-positive naive pregnant women enrolled in the project during the years 2005-2008. Full protease and partial reverse transcriptase sequencing was performed and 68/95 (71.6%) samples were successfully sequenced. Major mutations to nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors, and protease inhibitors were detected in 4/68 (5.9%), 3/68 (4.4%), and 2/68 (2.9%) samples, respectively. Phylogenetic analysis of HIV-1 isolates showed a high prevalence of unique recombinant forms (24/68, 35%), followed by CRF45_cpx (7/68, 10.3%) and subsubtype A3 and subtype G (6/68 each, 8.8%). Although the prevalence of transmitted drug resistance mutations appears to be currently limited, baseline HIV-1 genotyping is highly advisable in conjunction with antiretroviral therapy scale-up in resource-limited settings to optimize treatment and prevent perinatal transmission. PMID:25970260

  11. Behaviour change and competitive exclusion can explain the diverging HIV-1 and HIV-2 prevalence trends in Guinea-Bissau.

    PubMed

    Schmidt, W P; Van Der Loeff, M Schim; Aaby, P; Whittle, H; Bakker, R; Buckner, M; Dias, F; White, R G

    2008-04-01

    The aim of this study was to determine whether a temporary rise in sexual risk behaviour during war in Guinea-Bissau could explain the observed trends in HIV-1 and HIV-2 prevalence, and to explore the possible contribution of competitive elimination of HIV-2 by HIV-1. A simulation model of the heterosexual transmission of sexually transmitted infections was parameterized using demographic, behavioural and epidemiological data from rural Guinea-Bissau, and fitted to the observed HIV-1 and HIV-2 trends with and without a historic rise in risk behaviour. The observed trends could only be simulated by assuming a temporary rise in risk behaviour. Around 30% of the projected decline in HIV-2 prevalence from a peak of 8.7% to 4.3% in 2010 was due to competitive elimination by HIV-1. Importantly for public health, HIV-1 prevalence was predicted to continue increasing and to become the dominant HIV type by 2010. Data collection is required to validate this prediction.

  12. Innate Invariant NKT Cell Recognition of HIV-1–Infected Dendritic Cells Is an Early Detection Mechanism Targeted by Viral Immune Evasion

    PubMed Central

    Paquin-Proulx, Dominic; Gibbs, Anna; Bächle, Susanna M.; Checa, Antonio; Introini, Andrea; Leeansyah, Edwin; Wheelock, Craig E.; Nixon, Douglas F.; Broliden, Kristina; Tjernlund, Annelie; Moll, Markus

    2016-01-01

    Invariant NKT (iNKT) cells are innate-like T cells that respond rapidly with a broad range of effector functions upon recognition of glycolipid Ags presented by CD1d. HIV-1 carries Nef- and Vpu-dependent mechanisms to interfere with CD1d surface expression, indirectly suggesting a role for iNKT cells in control of HIV-1 infection. In this study, we investigated whether iNKT cells can participate in the innate cell–mediated immune response to HIV-1. Infection of dendritic cells (DCs) with Nef- and Vpu-deficient HIV-1 induced upregulation of CD1d in a TLR7-dependent manner. Infection of DCs caused modulation of enzymes in the sphingolipid pathway and enhanced expression of the endogenous glucosylceramide Ag. Importantly, iNKT cells responded specifically to rare DCs productively infected with Nef- and Vpu-defective HIV-1. Transmitted founder viral isolates differed in their CD1d downregulation capacity, suggesting that diverse strains may be differentially successful in inhibiting this pathway. Furthermore, both iNKT cells and DCs expressing CD1d and HIV receptors resided in the female genital mucosa, a site where HIV-1 transmission occurs. Taken together, these findings suggest that innate iNKT cell sensing of HIV-1 infection in DCs is an early immune detection mechanism, which is independent of priming and adaptive recognition of viral Ag, and is actively targeted by Nef- and Vpu-dependent viral immune evasion mechanisms. PMID:27481843

  13. Innate Invariant NKT Cell Recognition of HIV-1-Infected Dendritic Cells Is an Early Detection Mechanism Targeted by Viral Immune Evasion.

    PubMed

    Paquin-Proulx, Dominic; Gibbs, Anna; Bächle, Susanna M; Checa, Antonio; Introini, Andrea; Leeansyah, Edwin; Wheelock, Craig E; Nixon, Douglas F; Broliden, Kristina; Tjernlund, Annelie; Moll, Markus; Sandberg, Johan K

    2016-09-01

    Invariant NKT (iNKT) cells are innate-like T cells that respond rapidly with a broad range of effector functions upon recognition of glycolipid Ags presented by CD1d. HIV-1 carries Nef- and Vpu-dependent mechanisms to interfere with CD1d surface expression, indirectly suggesting a role for iNKT cells in control of HIV-1 infection. In this study, we investigated whether iNKT cells can participate in the innate cell-mediated immune response to HIV-1. Infection of dendritic cells (DCs) with Nef- and Vpu-deficient HIV-1 induced upregulation of CD1d in a TLR7-dependent manner. Infection of DCs caused modulation of enzymes in the sphingolipid pathway and enhanced expression of the endogenous glucosylceramide Ag. Importantly, iNKT cells responded specifically to rare DCs productively infected with Nef- and Vpu-defective HIV-1. Transmitted founder viral isolates differed in their CD1d downregulation capacity, suggesting that diverse strains may be differentially successful in inhibiting this pathway. Furthermore, both iNKT cells and DCs expressing CD1d and HIV receptors resided in the female genital mucosa, a site where HIV-1 transmission occurs. Taken together, these findings suggest that innate iNKT cell sensing of HIV-1 infection in DCs is an early immune detection mechanism, which is independent of priming and adaptive recognition of viral Ag, and is actively targeted by Nef- and Vpu-dependent viral immune evasion mechanisms.

  14. Design and Development of a Multiplex Real-Time PCR Assay for Detection of HIV-1 and HCV Using Molecular Beacons.

    PubMed

    Paryan, Mahdi; Mohammadi-Yeganeh, Samira; Mirab Samiee, Siamak; Rezvan, Houri

    2012-09-01

    At least 10 million individuals worldwide are co-infected with immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV). These two viruses are transmitted most primarily by exposure to infected blood or blood products. Various nucleic acid assays have been developed for diagnostics and therapeutic monitoring of infections. In the present study, a multiplex real-time PCR assay for simultaneous detection of HCV and HIV-1 using molecular beacons were designed and validated. A well-conserved region in the HIV-1 pol gene and 5'NCR of HCV genome were used for primers and molecular beacon design. The analysis of scalar concentrations of the samples indicated that this multiplex procedure detects at least 1,000 copies/ml of HIV-1 and 100 copies/ml of HCV with linear reference curve (R (2) > 0.94). The results demonstrate that a specificity of 100 % and sensitivity of 96 % can be achieved. The analytical sensitivity study with BLAST software demonstrated that the primers do not attach to any other sequences except for that of HIV-1 or HCV. The primers and molecular beacon probes only detected HIV-1 and all major variants of HCV. This assay may represent an alternative rapid and relatively inexpensive screening method for detection of HIV-1/HCV co-infection especially in blood screening.

  15. Enhanced Sensitivity for Detection of HIV-1 p24 Antigen by a Novel Nuclease-Linked Fluorescence Oligonucleotide Assay

    PubMed Central

    Fan, Peihu; Li, Xiaojun; Su, Weiheng; Kong, Wei; Kong, Xianggui; Wang, Zhenxin; Wang, Youchun; Jiang, Chunlai; Gao, Feng

    2015-01-01

    The relatively high detection limit of the Enzyme-linked immunosorbent assay (ELISA) prevents its application for detection of low concentrations of antigens. To increase the sensitivity for detection of HIV-1 p24 antigen, we developed a highly sensitive nuclease-linked fluorescence oligonucleotide assay (NLFOA). Two major improvements were incorporated in NLFOA to amplify antibody-antigen interaction signals and reduce the signal/noise ratio; a large number of nuclease molecules coupled to the gold nanoparticle/streptavidin complex and fluorescent signals generated from fluorescent-labeled oligonucleotides by the nuclease. The detection limit of p24 by NLFOA was 1 pg/mL, which was 10-fold more sensitive than the conventional ELISA (10 pg/mL). The specificity was 100% and the coefficient of variation (CV) was 7.8% at low p24 concentration (1.5 pg/mL) with various concentrations of spiked p24 in HIV-1 negative sera. Thus, NLFOA is highly sensitive, specific, reproducible and user-friendly. The more sensitive detection of low p24 concentrations in HIV-1-infected individuals by NLFOA could allow detection of HIV-1 infections that are missed by the conventional ELISA at the window period during acute infection to further reduce the risk for HIV-1 infection due to the undetected HIV-1 in the blood products. Moreover, NLFOA can be easily applied to more sensitive detection of other antigens. PMID:25915630

  16. Enhanced Sensitivity for Detection of HIV-1 p24 Antigen by a Novel Nuclease-Linked Fluorescence Oligonucleotide Assay.

    PubMed

    Fan, Peihu; Li, Xiaojun; Su, Weiheng; Kong, Wei; Kong, Xianggui; Wang, Zhenxin; Wang, Youchun; Jiang, Chunlai; Gao, Feng

    2015-01-01

    The relatively high detection limit of the Enzyme-linked immunosorbent assay (ELISA) prevents its application for detection of low concentrations of antigens. To increase the sensitivity for detection of HIV-1 p24 antigen, we developed a highly sensitive nuclease-linked fluorescence oligonucleotide assay (NLFOA). Two major improvements were incorporated in NLFOA to amplify antibody-antigen interaction signals and reduce the signal/noise ratio; a large number of nuclease molecules coupled to the gold nanoparticle/streptavidin complex and fluorescent signals generated from fluorescent-labeled oligonucleotides by the nuclease. The detection limit of p24 by NLFOA was 1 pg/mL, which was 10-fold more sensitive than the conventional ELISA (10 pg/mL). The specificity was 100% and the coefficient of variation (CV) was 7.8% at low p24 concentration (1.5 pg/mL) with various concentrations of spiked p24 in HIV-1 negative sera. Thus, NLFOA is highly sensitive, specific, reproducible and user-friendly. The more sensitive detection of low p24 concentrations in HIV-1-infected individuals by NLFOA could allow detection of HIV-1 infections that are missed by the conventional ELISA at the window period during acute infection to further reduce the risk for HIV-1 infection due to the undetected HIV-1 in the blood products. Moreover, NLFOA can be easily applied to more sensitive detection of other antigens. PMID:25915630

  17. Enhanced Sensitivity for Detection of HIV-1 p24 Antigen by a Novel Nuclease-Linked Fluorescence Oligonucleotide Assay.

    PubMed

    Fan, Peihu; Li, Xiaojun; Su, Weiheng; Kong, Wei; Kong, Xianggui; Wang, Zhenxin; Wang, Youchun; Jiang, Chunlai; Gao, Feng

    2015-01-01

    The relatively high detection limit of the Enzyme-linked immunosorbent assay (ELISA) prevents its application for detection of low concentrations of antigens. To increase the sensitivity for detection of HIV-1 p24 antigen, we developed a highly sensitive nuclease-linked fluorescence oligonucleotide assay (NLFOA). Two major improvements were incorporated in NLFOA to amplify antibody-antigen interaction signals and reduce the signal/noise ratio; a large number of nuclease molecules coupled to the gold nanoparticle/streptavidin complex and fluorescent signals generated from fluorescent-labeled oligonucleotides by the nuclease. The detection limit of p24 by NLFOA was 1 pg/mL, which was 10-fold more sensitive than the conventional ELISA (10 pg/mL). The specificity was 100% and the coefficient of variation (CV) was 7.8% at low p24 concentration (1.5 pg/mL) with various concentrations of spiked p24 in HIV-1 negative sera. Thus, NLFOA is highly sensitive, specific, reproducible and user-friendly. The more sensitive detection of low p24 concentrations in HIV-1-infected individuals by NLFOA could allow detection of HIV-1 infections that are missed by the conventional ELISA at the window period during acute infection to further reduce the risk for HIV-1 infection due to the undetected HIV-1 in the blood products. Moreover, NLFOA can be easily applied to more sensitive detection of other antigens.

  18. Evaluation of Immune Survival Factors in Pediatric HIV-1 Infection

    PubMed Central

    SHEARER, WILLIAM T.; EASLEY, KIRK A.; GOLDFARB, JOHANNA; JENSON, HAL B.; ROSENBLATT, HOWARD M.; KOVACS, ANDREA; MCINTOSH, KENNETH

    2015-01-01

    Peripheral blood CD4+ and CD8+ T cells, CD19+/20+ B cells, and serum immunoglobulins (Igs) have been implicated as survival factors for pediatric HIV-1 infection. To determine which of these immune factors might be important in predicting survival, we studied HIV-1 vertically infected (HIV-1+) children over a 5-year period. Peripheral blood lymphocytes and Igs were measured in 298 HIV-1+ children, who were classified as survivors or nonsurvivors, and in 463 HIV-1 vertically exposed and noninfected (HIV-1–) children. Measurements of other possible survival factors were included in this study: albumin, hemoglobin, lactic dehydrogenase (LDH), and HIV-1 RNA levels. Survivors had significantly higher CD4+ T-cell, CD8+ T-cell, and CD19+/CD20+ B-cell counts and serum IgG levels, but lower serum IgA and IgM levels than nonsurvivors. Serum albumin and blood hemoglobin levels were higher, but serum LDH and HIV-1 RNA levels were lower in the survivors compared to non-survivors. In univariable analysis, factors affecting survival were baseline CD4+ T-cell and CD8+ T-cell counts, IgG, albumin, hemoglobin, LDH, and HIV-1 RNA (all p < 0.001). In multivariable analysis, high baseline CD4+ T-cell count, IgG and albumin levels, and low baseline HIV-1 RNA load remained important factors for survival. Serum IgG level has been identified as an immune factor that independently predicts survival, in addition to the already established CD4+ T-cell count. The HIV-1 RNA and serum albumin levels also predicted survival. PMID:11144332

  19. Update: transmission of HIV-1 from mother to child.

    PubMed

    Fowler, M G

    1997-12-01

    Mother-to-child transmission near the time of birth is the primary route of HIV-1 infection among infants and young children. Throughout the world, 1000 babies a day become infected with HIV, and cumulative global estimates are that 3 million children have been infected since the HIV pandemic began. Although major advances have been made in reducing mother-to-child transmission of HIV-1 in the USA and Europe through the use of an intensive regimen of zidovudine, many research questions remain unresolved. These include (1) viral and host characteristics which hinder or facilitate perinatal HIV transmission (i.e. the role played by viral load, the placenta and obstetric risk factors); (2) the proportion of transmission occurring in utero, intrapartum or during the breast feeding period; and (3) the mode of action of the successful zidovudine regimen. Studies published within the past year have shed light on several of these research topics. In 1996-1997 a number of important studies were published which support a general correlation between maternal viral load and infant HIV infection. The most recent studies do not, however, support the theory that there is a threshold below which transmission cannot occur, and also indicate that zidovudine, given according to the US Public Health Service guidelines, can significantly reduce the risk of transmission across all levels of maternal viral load. Analyses of viral load data from the successful clinical trial with zidovudine (AIDS Clinical Trial Group 076) suggest that its primary action is not by reducing the viral load, and raise the possibility that administering antiretroviral prophylaxis to the infant at the time of highest exposure may be another reason for the reduction in transmission. Obstetric risk factors for mother-to-child HIV transmission have been evaluated in several large cohort studies. A duration of membrane rupture of more than 4 h, and procedures such as amniocentesis, preterm labor, and the presence

  20. LFA-1 Engagement Triggers T Cell Polarization at the HIV-1 Virological Synapse

    PubMed Central

    Starling, Shimona

    2016-01-01

    ABSTRACT HIV-1 efficiently disseminates by cell-cell spread at intercellular contacts called virological synapses (VS), where the virus preferentially assembles and buds. Cell-cell contact triggers active polarization of organelles and viral proteins within infected cells to the contact site to support efficient VS formation and HIV-1 spread; critically, however, which cell surface protein triggers contact-induced polarization at the VS remains unclear. Additionally, the mechanism by which the HIV-1 envelope glycoprotein (Env) is recruited to the VS remains ill defined. Here, we use a reductionist bead-coupled antibody assay as a model of the VS and show that cross-linking the integrin LFA-1 alone is sufficient to induce active T cell polarization and recruitment of the microtubule organizing center (MTOC) in HIV-1-infected cells. Mutant cell lines coupled with inhibitors demonstrated that LFA-1-induced polarization was dependent on the T cell kinase ZAP70. Notably, immunofluorescent staining of viral proteins revealed an accumulation of surface Env at sites of LFA-1 engagement, with intracellular Env localized to a Golgi compartment proximal to the polarized MTOC. Furthermore, blocking LFA-1-induced MTOC polarization through ZAP70 inhibition prevented intracellular Env polarization. Taken together, these data reveal that LFA-1 is a key determinant in inducing dynamic T cell remodeling to the VS and suggest a model in which LFA-1 engagement triggers active polarization of the MTOC and the associated Env-containing secretory apparatus to sites of cell-cell contact to support polarized viral assembly and egress for efficient cell-cell spread. IMPORTANCE HIV-1 causes AIDS by spreading within immune cells and depletion of CD4 T lymphocytes. Rapid spread between these cells occurs by highly efficient cell-cell transmission that takes place at virological synapses (VS). VS are characterized by striking T cell remodeling that is spatially associated with polarized virus

  1. Striking HIV-1 Entry by Targeting HIV-1 gp41. But, Where Should We Target?

    PubMed Central

    Teixeira, Cátia; Barbault, Florent; Couesnon, Thierry; Gomes, José R. B.; Gomes, Paula; Maurel, François

    2016-01-01

    HIV-1 gp41 facilitates the viral fusion through a conformational switch involving the association of three C-terminal helices along the conserved hydrophobic grooves of three N-terminal helices coiled-coil. The control of these structural rearrangements is thought to be central to HIV-1 entry and, therefore, different strategies of intervention are being developed. Herewith, we describe a procedure to simulate the folding of an HIV-1 gp41 simplified model. This procedure is based on the construction of plausible conformational pathways, which describe protein transition between non-fusogenic and fusogenic conformations. The calculation of the paths started with 100 molecular dynamics simulations of the non-fusogenic conformation, which were found to converge to different intermediate states. Those presenting defined criteria were selected for separate targeted molecular dynamics simulations, subjected to a force constant imposing a movement towards the gp41 fusogenic conformation. Despite significant diversity, a preferred sequence of events emerged when the simulations were analyzed in terms of the formation, breakage and evolution of the contacts. We pointed out 29 residues as the most relevant for the movement of gp41; also, 2696 possible interactions were reduced to only 48 major interactions, which reveals the efficiency of the method. The analysis of the evolution of the main interactions lead to the detection of four main behaviors for those contacts: stable, increasing, decreasing and repulsive interactions. Altogether, these results suggest a specific small cavity of the HIV-1 gp41 hydrophobic groove as the preferred target to small molecules. PMID:26785380

  2. Quantitative HIV-1 proviral DNA detection: a multicentre analysis.

    PubMed

    De Rossi, Anita; Zanchetta, Marisa; Vitone, Francesca; Antonelli, Guido; Bagnarelli, Patrizia; Buonaguro, Luigi; Capobianchi, Maria Rosaria; Clementi, Massimo; Abbate, Isabella; Canducci, Filippo; Monachetti, Alessia; Riva, Elisabetta; Rozera, Gabriella; Scagnolari, Carolina; Tagliamonte, Maria; Re, Maria Carla

    2010-10-01

    Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients. PMID:21213587

  3. Iron chelators ICL670 and 311 inhibit HIV-1 transcription

    SciTech Connect

    Debebe, Zufan; Ammosova, Tatyana; Jerebtsova, Marina; Kurantsin-Mills, Joseph; Niu, Xiaomei; Charles, Sharroya; Richardson, Des R.; Ray, Patricio E.; Gordeuk, Victor R.; Nekhai, Sergei

    2007-10-25

    HIV-1 replication is induced by an excess of iron and iron chelation by desferrioxamine (DFO) inhibits viral replication by reducing proliferation of infected cells. Treatment of cells with DFO and 2-hydroxy-1-naphthylaldehyde isonicotinoyl hydrazone (311) inhibit expression of proteins that regulate cell-cycle progression, including cycle-dependent kinase 2 (CDK2). Our recent studies showed that CDK2 participates in HIV-1 transcription and viral replication suggesting that inhibition of CDK2 by iron chelators might also affect HIV-1 transcription. Here we evaluated the effect of a clinically approved orally effective iron chelator, 4-[3,5-bis-(hydroxyphenyl)-1,2,4-triazol-1-yl]-benzoic acid (ICL670) and 311 on HIV-1 transcription. Both ICL670 and 311 inhibited Tat-induced HIV-1 transcription in CEM-T cells, 293T and HeLa cells. Neither ICL670 nor 311 induced cytotoxicity at concentrations that inhibited HIV-1 transcription. The chelators decreased cellular activity of CDK2 and reduced HIV-1 Tat phosphorylation by CDK2. Neither ICL670A or 311 decreased CDK9 protein level but significantly reduced association of CDK9 with cyclin T1 and reduced phosphorylation of Ser-2 residues of RNA polymerase II C-terminal domain. In conclusion, our findings add to the evidence that iron chelators can inhibit HIV-1 transcription by deregulating CDK2 and CDK9. Further consideration should be given to the development of iron chelators for future anti-retroviral therapeutics.

  4. [A new unique HIV-1 recombinant form detected in Belarus].

    PubMed

    Eremin, V F; Gasich, E L; Sosinovich, S V

    2012-01-01

    Republican Research-and-Practical Center for Epidemiology and Microbiology, Ministry of Health of Belarus, Minsk The paper presents data on the molecular genetic characteristics of a new HIV-1 recombinant form. The study has shown that the virus is referred to as HIV-1 subtype B in terms of the gag gene and HIV-1 subtype A in terms of the pol and env genes. At the same time the new isolate is closer, in terms of the gag gene, to the HIV-1 DQ207943 strain isolated in Georgia, in terms of the pol gene, to the HIV-1 AF413987.1 strain isolated in Ukraine and, in terms of the env gene to the HIV-1 AY500393 strain isolated in Russia. Thus, the described new HIV-1 recombinant form has the following structure: BgagApolAenv. The gag, pol, and env gene sequences from the new unique HIV-1 recombinant form have been registered in the international database EMBL/Genbank/DDBJ under accession numbers FR775442.1, FN995656.1, and FR775443.1.

  5. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    PubMed

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants. PMID:24802562

  6. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    PubMed

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants.

  7. Multifarious immunotherapeutic approaches to cure HIV-1 infection.

    PubMed

    Imami, Nesrina; Herasimtschuk, Anna A

    2015-01-01

    Immunotherapy in the context of treated HIV-1 infection aims to improve immune responses to achieve better control of the virus. To date, multifaceted immunotherapeutic approaches have been shown to reduce immune activation and increase CD4 T-lymphocyte counts, further to the effects of antiretroviral therapy alone, in addition to improving HIV-1-specific T-cell responses. While sterilizing cure of HIV-1 would involve elimination of all replication-competent virus, a functional cure in which the host has long-lasting control of viral replication may be more feasible. In this commentary, we discuss novel strategies aimed at targeting the latent viral reservoir with cure of HIV-1 infection being the ultimate goal, an achievement that would have considerable impact on worldwide HIV-1 infection.

  8. Which therapeutic strategy will achieve a cure for HIV-1?

    PubMed

    Cillo, Anthony R; Mellors, John W

    2016-06-01

    Strategies to achieve a cure for HIV-1 infection can be broadly classified into three categories: eradication cure (elimination of all viral reservoirs), functional cure (immune control without reservoir eradication), or a hybrid cure (reservoir reduction with improved immune control). The many HIV-1 cure strategies being investigated include modification of host cells to resist HIV-1, engineered T cells to eliminate HIV-infected cells, broadly HIV-1 neutralizing monoclonal antibodies, and therapeutic vaccination, but the 'kick and kill' strategy to expose latent HIV-1 with latency reversing agents (LRAs) and kill the exposed cells through immune effector functions is currently the most actively pursued. It is unknown, however, whether LRAs can deplete viral reservoirs in vivo or whether current LRAs are sufficiently safe for clinical use.

  9. Modeling HIV-1 Mucosal Transmission and Prevention in Humanized Mice.

    PubMed

    Veselinovic, Milena; Charlins, Paige; Akkina, Ramesh

    2016-01-01

    The new generation humanized mice (hu-mice) that permit continuous de novo generation of human hematopoietic cells have led to novel strategies in studying HIV-1 pathogenesis, prevention and therapies. HIV-1 infection of hu-mice results in chronic viremia and CD4+ T cell loss, thus mimicking key aspects of the disease progression. In addition, the new generation hu-mice are permissive for HIV-1 sexual transmission by vaginal and rectal routes thus allowing in vivo efficacy testing of new anti-HIV-1 drugs for prevention. Two leading models are currently being used, namely the hu-HSC mice and the BLT mice. Here we describe the methodology for generating both hu-HSC and BLT mice and their use in the study of HIV-1 transmission and prevention of infection by topical and oral administration of anti-retroviral drugs. Practical aspects of the methodologies are emphasized.

  10. HIV-1 and interferons: who's interfering with whom?

    PubMed

    Doyle, Tomas; Goujon, Caroline; Malim, Michael H

    2015-07-01

    The ability of interferons (IFNs) to inhibit HIV-1 replication in cell culture models has long been recognized, and the therapeutic administration of IFNα to HIV-1-infected patients who are not receiving antiretroviral therapy produces a clear but transient decrease in plasma viral load. Conversely, studies of chronic HIV-1 infection in humans and SIV-infected animal models of AIDS show positive correlations between elevated plasma levels of IFNs, increased expression of IFN-stimulated genes (ISGs), biomarkers of inflammation and disease progression. In this Review, we discuss the evidence that IFNs can control HIV-1 replication in vivo and debate the controversial role of IFNs in promoting the pathological sequelae of chronic HIV-1 infection.

  11. HIV-1 infection, microenvironment and endothelial cell dysfunction.

    PubMed

    Mazzuca, Pietro; Caruso, Arnaldo; Caccuri, Francesca

    2016-09-01

    HIV-1 promotes a generalized immune activation that involves the main targets of HIV-1 infection but also cells that are not sensitive to viral infection. ECs display major dysfunctions in HIV+ patients during long-standing viral infection that persist even in the current cART era, in which new-generation drugs have reduced dysmetabolic side effects and successfully impeded viral replication. In vivo studies have failed to demonstrate the presence of replicating virus in ECs suggesting that a direct role of the virus is unlikely, and implying that the mechanism accounting for vascular dysfunction may rely on the indirect action of molecules released in the microenvironment by HIV-1-infected cells. This article reviews the current understanding of how HIV-1 infection can contribute to vascular dysfunction. In particular, we discuss the emerging role played by different HIV-1 proteins in driving inflammation and EC dysregulation, and highlight the need to target them for therapeutic benefit. PMID:27602413

  12. Recombination elevates the effective evolutionary rate and facilitates the establishment of HIV-1 infection in infants after mother-to-child transmission

    DOE PAGES

    Sanborn, Keri B.; Somasundaran, Mohan; Luzuriaga, Katherine; Leitner, Thomas K.

    2015-11-16

    Some previous studies have demonstrated that single HIV-1 genotypes are commonly transmitted from mother to child, but such analyses primarily used single samples from mother and child. It is possible that in a single sample, obtained early after infection, only the most replication competent virus is detected even when other forms may have been transmitted. Such forms may have advantages later in infection, and may thus be detected in follow-up samples. Furthermore, because HIV-1 frequently recombines, phylogenetic analyses that ignore recombination may miss transmission of multiple forms if they recombine after transmission. Moreover, recombination may facilitate adaptation, thus providing anmore » advantage in establishing infection. The effect of recombination on viral evolution in HIV-1 infected children has not been well defined.« less

  13. Recombination elevates the effective evolutionary rate and facilitates the establishment of HIV-1 infection in infants after mother-to-child transmission

    SciTech Connect

    Sanborn, Keri B.; Somasundaran, Mohan; Luzuriaga, Katherine; Leitner, Thomas K.

    2015-11-16

    Some previous studies have demonstrated that single HIV-1 genotypes are commonly transmitted from mother to child, but such analyses primarily used single samples from mother and child. It is possible that in a single sample, obtained early after infection, only the most replication competent virus is detected even when other forms may have been transmitted. Such forms may have advantages later in infection, and may thus be detected in follow-up samples. Furthermore, because HIV-1 frequently recombines, phylogenetic analyses that ignore recombination may miss transmission of multiple forms if they recombine after transmission. Moreover, recombination may facilitate adaptation, thus providing an advantage in establishing infection. The effect of recombination on viral evolution in HIV-1 infected children has not been well defined.

  14. Nonhuman TRIM5 Variants Enhance Recognition of HIV-1-Infected Cells by CD8+ T Cells

    PubMed Central

    Jimenez-Moyano, Esther; Ruiz, Alba; Kløverpris, Henrik N.; Rodriguez-Plata, Maria T.; Peña, Ruth; Blondeau, Caroline; Selwood, David L.; Izquierdo-Useros, Nuria; Moris, Arnaud; Clotet, Bonaventura; Goulder, Philip; Towers, Greg J.

    2016-01-01

    ABSTRACT Tripartite motif-containing protein 5 (TRIM5) restricts human immunodeficiency virus type 1 (HIV-1) in a species-specific manner by uncoating viral particles while activating early innate responses. Although the contribution of TRIM5 proteins to cellular immunity has not yet been studied, their interactions with the incoming viral capsid and the cellular proteasome led us to hypothesize a role for them. Here, we investigate whether the expression of two nonhuman TRIM5 orthologs, rhesus TRIM5α (RhT5) and TRIM-cyclophilin A (TCyp), both of which are potent restrictors of HIV-1, could enhance immune recognition of infected cells by CD8+ T cells. We illustrate how TRIM5 restriction improves CD8+ T-cell-mediated HIV-1 inhibition. Moreover, when TRIM5 activity was blocked by the nonimmunosuppressive analog of cyclosporine (CsA), sarcosine-3(4-methylbenzoate)–CsA (SmBz-CsA), we found a significant reduction in CD107a/MIP-1β expression in HIV-1-specific CD8+ T cells. This finding underscores the direct link between TRIM5 restriction and activation of CD8+ T-cell responses. Interestingly, cells expressing RhT5 induced stronger CD8+ T-cell responses through the specific recognition of the HIV-1 capsid by the immune system. The underlying mechanism of this process may involve TRIM5-specific capsid recruitment to cellular proteasomes and increase peptide availability for loading and presentation of HLA class I antigens. In summary, we identified a novel function for nonhuman TRIM5 variants in cellular immunity. We hypothesize that TRIM5 can couple innate viral sensing and CD8+ T-cell activation to increase species barriers against retrovirus infection. IMPORTANCE New therapeutics to tackle HIV-1 infection should aim to combine rapid innate viral sensing and cellular immune recognition. Such strategies could prevent seeding of the viral reservoir and the immune damage that occurs during acute infection. The nonhuman TRIM5 variants, rhesus TRIM5α (RhT5) and TRIM

  15. Microbicides for the Treatment of Sexually Transmitted HIV Infections

    PubMed Central

    Singh, Onkar; Garg, Tarun; Rath, Goutam; Goyal, Amit K.

    2014-01-01

    Approximately 34 million people were living with human immunodeficiency virus (HIV-1) at the end of 2011. From the last two decades, researchers are actively involved in the development of an effective HIV-1 treatment, but the results intended are still doubtful about the eradication of HIV. The HIV-1 virus has gone from being an “inherently untreatable” infectious agent to the one liable to be affected by a range of approved therapies. Candidate microbicides have been developed to target specific steps in the process of viral transmission. Microbicides are self-administered agents that can be applied to vaginal or rectal mucosal surfaces with the aim of preventing, or reducing, the transmission of sexually transmitted infections (STIs) including HIV-1. The development of efficient, widely available, and low-cost microbicides to prevent sexually transmitted HIV infections should be given high priority. In this review, we studied the various forms of microbicides, their mechanism of action, and their abundant approaches to control the transmission of sexually transmitted infections (STIs). PMID:26556193

  16. Perinatal acquisition of drug-resistant HIV-1 infection: mechanisms and long-term outcome

    PubMed Central

    Delaugerre, Constance; Chaix, Marie-Laure; Blanche, Stephane; Warszawski, Josiane; Cornet, Dorine; Dollfus, Catherine; Schneider, Veronique; Burgard, Marianne; Faye, Albert; Mandelbrot, Laurent; Tubiana, Roland; Rouzioux, Christine

    2009-01-01

    Background Primary-HIV-1-infection in newborns that occurs under antiretroviral prophylaxis that is a high risk of drug-resistance acquisition. We examine the frequency and the mechanisms of resistance acquisition at the time of infection in newborns. Patients and Methods We studied HIV-1-infected infants born between 01 January 1997 and 31 December 2004 and enrolled in the ANRS-EPF cohort. HIV-1-RNA and HIV-1-DNA samples obtained perinatally from the newborn and mother were subjected to population-based and clonal analyses of drug resistance. If positive, serial samples were obtained from the child for resistance testing. Results Ninety-two HIV-1-infected infants were born during the study period. Samples were obtained from 32 mother-child pairs and from another 28 newborns. Drug resistance was detected in 12 newborns (20%): drug resistance to nucleoside reverse transcriptase inhibitors was seen in 10 cases, non-nucleoside reverse transcriptase inhibitors in two cases, and protease inhibitors in one case. For 9 children, the detection of the same resistance mutations in mothers' samples (6 among 10 available) and in newborn lymphocytes (6/8) suggests that the newborn was initially infected by a drug-resistant strain. Resistance variants were either transmitted from mother-to-child or selected during subsequent temporal exposure under suboptimal perinatal prophylaxis. Follow-up studies of the infants showed that the resistance pattern remained stable over time, regardless of antiretroviral therapy, suggesting the early cellular archiving of resistant viruses. The absence of resistance in the mother of the other three children (3/10) and neonatal lymphocytes (2/8) suggests that the newborns were infected by a wild-type strain without long-term persistence of resistance when suboptimal prophylaxis was stopped. Conclusion This study confirms the importance of early resistance genotyping of HIV-1-infected newborns. In most cases (75%), drug resistance was archived in

  17. HIV-1 Vpr reactivates latent HIV-1 provirus by inducing depletion of class I HDACs on chromatin

    PubMed Central

    Romani, Bizhan; Kamali Jamil, Razieh; Hamidi-Fard, Mojtaba; Rahimi, Pooneh; Momen, Seyed Bahman; Aghasadeghi, Mohammad Reza; Allahbakhshi, Elham

    2016-01-01

    HIV-1 Vpr is an accessory protein that induces proteasomal degradation of multiple proteins. We recently showed that Vpr targets class I HDACs on chromatin for proteasomal degradation. Here we show that Vpr induces degradation of HDAC1 and HDAC3 in HIV-1 latently infected J-Lat cells. Degradation of HDAC1 and HDAC3 was also observed on the HIV-1 LTR and as a result, markers of active transcription were recruited to the viral promoter and induced viral activation. Knockdown of HDAC1 and HDAC3 activated the latent HIV-1 provirus and complementation with HDAC3 inhibited Vpr-induced HIV-1 reactivation. Viral reactivation and degradation of HDAC1 and HDAC3 was conserved among Vpr proteins of HV-1 group M. Serum Vpr isolated from patients or the release of virion-incorporated Vpr from viral lysates also activated HIV-1 in latently infected cell lines and PBMCs from HIV-1 infected patients. Our results indicate that Vpr counteracts HIV-1 latency by inducing proteasomal degradation of HDAC1 and 3 leading to reactivation of the viral promoter. PMID:27550312

  18. APOBEC3H Haplotypes and HIV-1 Pro-Viral vif DNA Sequence Diversity in Early Untreated HIV-1 Infection

    PubMed Central

    Gourraud, PA; Karaouni, A; Woo, JM; Schmidt, T; Oksenberg, JR; Hecht, FM; Liegler, TJ; Barbour, JD

    2011-01-01

    We examined single nucleotide polymorphisms (SNP) in the APOBEC3 locus on chromosome 22, paired to population sequences of pro-viral HIV-1 vif of peripheral blood mononuclear cells (PBMC), from 96 recently HIV-1 infected treatment naïve adults. We found evidence for the existence of an APOBEC3H linkage disequilibrium (LD) block associated with variation in GA->AA, or APOBEC3F signature, sequence changes in pro-viral HIV-1 vif sequence (top significant 10 SNPs with a top-significant p=4.8×10−3). We identified a common 5 position risk haplotype distal to APOBEC3H (A3Hrh). These markers were in high LD (D′ = 1; r2=0.98) to a previously described A3H ‘RED’ haplotype containing a variant (E121) with enhanced susceptibility to HIV-1 Vif (Zhen et al 2009 [1]). This association is confirmed by a haplotype analysis: Homozygote carriers of the A3Hrh had lower GA->AA (A3F) sequence editing on pro-viral HIV-1 vif sequence (p = 0.01), and lower HIV-1 RNA levels over time during early, untreated HIV-1 infection, (p = 0.015 mixed effects model). This effect may be due to enhanced susceptibility of A3H forms to HIV-1 Vif mediated viral suppression of sequence editing activity, slowing viral diversification and escape from immune responses. PMID:21167246

  19. Molecular Epidemiology of HIV-1 Infection among Men who Have Sex with Men in Taiwan in 2012

    PubMed Central

    Huang, Szu-Wei; Wang, Sheng-Fan; Cowó, Ángel E.; Chen, Marcelo; Lin, Yu-Ting; Hung, Chun-Po; Chen, Yi-Hsien; Yang, Jyh-Yuan; Tang, Hung-Jen; Chen, Yi-Ming Arthur

    2015-01-01

    The number of men who have sex with men (MSM) infected with HIV-1 in Taiwan has increased rapidly in the past few years. The goal of this study was to conduct a molecular epidemiological study of HIV-1 infection among MSM in Taiwan to identify risk factors for intervention. Voluntary counseling program and anonymous testing were provided to patrons at 1 gay bar, 7 night clubs and 3 gay saunas in Taipei and New Taipei Cities in 2012. HIV-1 subtypes were determined using gag subtype-specific PCR and phylogenetic analysis by env sequences. Recent HIV-1 infection was determined using LAg-Avidity EIA. In-depth interviews and questionnaires were used to identify risk factors. The prevalence and incidence of HIV-1 among MSM in Taiwan were 4.38% (53/1,208) and 3.29 per 100 person-years, respectively. Of 49 cases genotyped, 48 (97.9%) were infected with subtype B and 1 with CRF01_AE (2%). Phylogenetic analysis of 46 HIV-1 strains showed that 25 (54.4%) subtype B strains formed 9 clusters with each other or with other local strains. The CRF01_AE case clustered with a reference strain from a Thai blood donor with bootstrap value of 99. Multivariate logistic regression analysis showed that risk factors associated with HIV-1 infection included use of oil-based solution as lubricant (vs. saliva or water-based lubricants, OR= 4.23; p <0.001); exclusively receptive role (vs. insertive role, OR= 9.69; p <0.001); versatile role (vs. insertive role, OR= 6.45; p= 0.003); oral sex (vs. insertive role, OR= 11.93; p= 0.044); times of sexual contact per week (2-3 vs. zero per week, OR= 3.41; p= 0.021); illegal drug use (OR= 4.12; p <0.001); and history of sexually transmitted diseases (OR= 3.65; p= 0.002). In conclusion, there was no new HIV-1 subtype or circulating recombinant form responsible for the increase of HIV-1 among MSM in Taiwan in 2012. Misuse of oil-based solution as lubricant is a new risk factor identified among MSM in Taiwan. The Taiwan’s Centers for Disease Control has

  20. Molecular Epidemiology of HIV-1 Infection among Men who Have Sex with Men in Taiwan in 2012.

    PubMed

    Huang, Szu-Wei; Wang, Sheng-Fan; Cowó, Ángel E; Chen, Marcelo; Lin, Yu-Ting; Hung, Chun-Po; Chen, Yi-Hsien; Yang, Jyh-Yuan; Tang, Hung-Jen; Chen, Yi-Ming Arthur

    2015-01-01

    The number of men who have sex with men (MSM) infected with HIV-1 in Taiwan has increased rapidly in the past few years. The goal of this study was to conduct a molecular epidemiological study of HIV-1 infection among MSM in Taiwan to identify risk factors for intervention. Voluntary counseling program and anonymous testing were provided to patrons at 1 gay bar, 7 night clubs and 3 gay saunas in Taipei and New Taipei Cities in 2012. HIV-1 subtypes were determined using gag subtype-specific PCR and phylogenetic analysis by env sequences. Recent HIV-1 infection was determined using LAg-Avidity EIA. In-depth interviews and questionnaires were used to identify risk factors. The prevalence and incidence of HIV-1 among MSM in Taiwan were 4.38% (53/1,208) and 3.29 per 100 person-years, respectively. Of 49 cases genotyped, 48 (97.9%) were infected with subtype B and 1 with CRF01_AE (2%). Phylogenetic analysis of 46 HIV-1 strains showed that 25 (54.4%) subtype B strains formed 9 clusters with each other or with other local strains. The CRF01_AE case clustered with a reference strain from a Thai blood donor with bootstrap value of 99. Multivariate logistic regression analysis showed that risk factors associated with HIV-1 infection included use of oil-based solution as lubricant (vs. saliva or water-based lubricants, OR= 4.23; p <0.001); exclusively receptive role (vs. insertive role, OR= 9.69; p <0.001); versatile role (vs. insertive role, OR= 6.45; p= 0.003); oral sex (vs. insertive role, OR= 11.93; p= 0.044); times of sexual contact per week (2-3 vs. zero per week, OR= 3.41; p= 0.021); illegal drug use (OR= 4.12; p <0.001); and history of sexually transmitted diseases (OR= 3.65; p= 0.002). In conclusion, there was no new HIV-1 subtype or circulating recombinant form responsible for the increase of HIV-1 among MSM in Taiwan in 2012. Misuse of oil-based solution as lubricant is a new risk factor identified among MSM in Taiwan. The Taiwan's Centers for Disease Control has

  1. Molecular Epidemiology of HIV-1 Infection among Men who Have Sex with Men in Taiwan in 2012.

    PubMed

    Huang, Szu-Wei; Wang, Sheng-Fan; Cowó, Ángel E; Chen, Marcelo; Lin, Yu-Ting; Hung, Chun-Po; Chen, Yi-Hsien; Yang, Jyh-Yuan; Tang, Hung-Jen; Chen, Yi-Ming Arthur

    2015-01-01

    The number of men who have sex with men (MSM) infected with HIV-1 in Taiwan has increased rapidly in the past few years. The goal of this study was to conduct a molecular epidemiological study of HIV-1 infection among MSM in Taiwan to identify risk factors for intervention. Voluntary counseling program and anonymous testing were provided to patrons at 1 gay bar, 7 night clubs and 3 gay saunas in Taipei and New Taipei Cities in 2012. HIV-1 subtypes were determined using gag subtype-specific PCR and phylogenetic analysis by env sequences. Recent HIV-1 infection was determined using LAg-Avidity EIA. In-depth interviews and questionnaires were used to identify risk factors. The prevalence and incidence of HIV-1 among MSM in Taiwan were 4.38% (53/1,208) and 3.29 per 100 person-years, respectively. Of 49 cases genotyped, 48 (97.9%) were infected with subtype B and 1 with CRF01_AE (2%). Phylogenetic analysis of 46 HIV-1 strains showed that 25 (54.4%) subtype B strains formed 9 clusters with each other or with other local strains. The CRF01_AE case clustered with a reference strain from a Thai blood donor with bootstrap value of 99. Multivariate logistic regression analysis showed that risk factors associated with HIV-1 infection included use of oil-based solution as lubricant (vs. saliva or water-based lubricants, OR= 4.23; p <0.001); exclusively receptive role (vs. insertive role, OR= 9.69; p <0.001); versatile role (vs. insertive role, OR= 6.45; p= 0.003); oral sex (vs. insertive role, OR= 11.93; p= 0.044); times of sexual contact per week (2-3 vs. zero per week, OR= 3.41; p= 0.021); illegal drug use (OR= 4.12; p <0.001); and history of sexually transmitted diseases (OR= 3.65; p= 0.002). In conclusion, there was no new HIV-1 subtype or circulating recombinant form responsible for the increase of HIV-1 among MSM in Taiwan in 2012. Misuse of oil-based solution as lubricant is a new risk factor identified among MSM in Taiwan. The Taiwan's Centers for Disease Control has

  2. Transmission of single and multiple viral variants in primary HIV-1 subtype C infection.

    PubMed

    Novitsky, Vladimir; Wang, Rui; Margolin, Lauren; Baca, Jeannie; Rossenkhan, Raabya; Moyo, Sikhulile; van Widenfelt, Erik; Essex, M

    2011-02-09

    To address whether sequences of viral gag and env quasispecies collected during the early post-acute period can be utilized to determine multiplicity of transmitted HIV's, recently developed approaches for analysis of viral evolution in acute HIV-1 infection [1,2] were applied. Specifically, phylogenetic reconstruction, inter- and intra-patient distribution of maximum and mean genetic distances, analysis of Poisson fitness, shape of highlighter plots, recombination analysis, and estimation of time to the most recent common ancestor (tMRCA) were utilized for resolving multiplicity of HIV-1 transmission in a set of viral quasispecies collected within 50 days post-seroconversion (p/s) in 25 HIV-infected individuals with estimated time of seroconversion. The decision on multiplicity of HIV infection was made based on the model's fit with, or failure to explain, the observed extent of viral sequence heterogeneity. The initial analysis was based on phylogeny, inter-patient distribution of maximum and mean distances, and Poisson fitness, and was able to resolve multiplicity of HIV transmission in 20 of 25 (80%) cases. Additional analysis involved distribution of individual viral distances, highlighter plots, recombination analysis, and estimation of tMRCA, and resolved 4 of the 5 remaining cases. Overall, transmission of a single viral variant was identified in 16 of 25 (64%) cases, and transmission of multiple variants was evident in 8 of 25 (32%) cases. In one case multiplicity of HIV-1 transmission could not be determined. In primary HIV-1 subtype C infection, samples collected within 50 days p/s and analyzed by a single-genome amplification/sequencing technique can provide reliable identification of transmission multiplicity in 24 of 25 (96%) cases. Observed transmission frequency of a single viral variant and multiple viral variants were within the ranges of 64% to 68%, and 32% to 36%, respectively.

  3. Cyclophilin B enhances HIV-1 infection.

    PubMed

    DeBoer, Jason; Madson, Christian J; Belshan, Michael

    2016-02-01

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. PMID:26774171

  4. A review of HIV-1 in Africa.

    PubMed

    Ronald, A R; Ndinya-Achola, J O; Plummer, F A; Simonsen, J N; Cameron, D W; Ngugi, E N; Pamba, H

    1988-01-01

    As the AIDS epidemic reaches a dramatic stage of development, the time for African countries to establish effective control programs has come. The history of AIDS in Africa is different from that other regions of the world. The disease developed among heterosexual communities. By 1987, over 8,000 cases of AIDS had been reported from 37 of the 47 nations of Africa. Over 2,000 of these cases were found in Uganda. However, under-reporting and under-representation of the number of actual cases is still a problem. In many cases, there has been a failure to recognize the disease. The demographic and geographic distribution of seroprevalence is discussed. Because of the inaccuracies in AIDS reporting in Africa, epidemic forecasting is difficult. If 5 million are currently infected, a potential 50 million Africans may be infected by 1993. A further discussion of the risk factors for HIV-1 holds that promiscuity is the major problem. Cures and inexpensive treatments for the infection are years away. Energy, resources, and national committees in Africa and the world must be coordinated to combat the ultimate crisis of this century.

  5. Anti-HIV-1 activity of flavonoid myricetin on HIV-1 infection in a dual-chamber in vitro model.

    PubMed

    Pasetto, Silvana; Pardi, Vanessa; Murata, Ramiro Mendonça

    2014-01-01

    HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01-100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic), H9 and PBMC cells plus HIV-1 MN (X4 tropic), and the dual tropic (X4R5) HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research.

  6. Anti-HIV-1 Activity of Flavonoid Myricetin on HIV-1 Infection in a Dual-Chamber In Vitro Model

    PubMed Central

    Pasetto, Silvana; Pardi, Vanessa; Murata, Ramiro Mendonça

    2014-01-01

    HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01–100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic), H9 and PBMC cells plus HIV-1 MN (X4 tropic), and the dual tropic (X4R5) HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research. PMID:25546350

  7. Particle infectivity of HIV-1 full-length genome infectious molecular clones in a subtype C heterosexual transmission pair following high fidelity amplification and unbiased cloning

    SciTech Connect

    Deymier, Martin J.; Claiborne, Daniel T.; Ende, Zachary; Ratner, Hannah K.; Kilembe, William; Hunter, Eric

    2014-11-15

    The high genetic diversity of HIV-1 impedes high throughput, large-scale sequencing and full-length genome cloning by common restriction enzyme based methods. Applying novel methods that employ a high-fidelity polymerase for amplification and an unbiased fusion-based cloning strategy, we have generated several HIV-1 full-length genome infectious molecular clones from an epidemiologically linked transmission pair. These clones represent the transmitted/founder virus and phylogenetically diverse non-transmitted variants from the chronically infected individual's diverse quasispecies near the time of transmission. We demonstrate that, using this approach, PCR-induced mutations in full-length clones derived from their cognate single genome amplicons are rare. Furthermore, all eight non-transmitted genomes tested produced functional virus with a range of infectivities, belying the previous assumption that a majority of circulating viruses in chronic HIV-1 infection are defective. Thus, these methods provide important tools to update protocols in molecular biology that can be universally applied to the study of human viral pathogens. - Highlights: • Our novel methodology demonstrates accurate amplification and cloning of full-length HIV-1 genomes. • A majority of plasma derived HIV variants from a chronically infected individual are infectious. • The transmitted/founder was more infectious than the majority of the variants from the chronically infected donor.

  8. Extensive Genetic Diversity of HIV-1 in Incident and Prevalent Infections among Malaysian Blood Donors: Multiple Introductions of HIV-1 Genotypes from Highly Prevalent Countries

    PubMed Central

    Chow, Wei Zhen; Bon, Abdul Hamid; Keating, Sheila; Anderios, Fread; Halim, Hazwan Abdul; Takebe, Yutaka; Kamarulzaman, Adeeba; Busch, Michael P.; Tee, Kok Keng

    2016-01-01

    Transfusion-transmissible infections including HIV-1 continue to pose major risks for unsafe blood transfusions due to both window phase infections and divergent viruses that may not be detected by donor screening assays. Given the recent emergence of several HIV-1 circulating recombinant forms (CRFs) in high-risk populations in the Southeast Asia region, we investigated the genetic diversity of HIV-1 among the blood donors in Kuala Lumpur, Malaysia. A total of 211 HIV-positive plasma samples detected among 730,188 donations to the National Blood Centre between 2013 and 2014 were provided (90.5% male, median age: 27.0 years old). Recent or long-term infection status at the time of donation was determined using a limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA). HIV-1 gag-pol genes were amplified and sequenced from residual plasma for 149 cases followed by genotype determination using phylogenetic and recombination analyses. Transmitted antiretroviral resistance mutations were not observed among the blood donors, among which 22.7% were classified as recent or incident infections. Major circulating HIV-1 genotypes determined by neighbour-joining phylogenetic inference included CRF01_AE at 40.9% (61/149), CRF33_01B at 21.5% (32/149), and subtype B at 10.1% (15/149). Newly-described CRFs including CRF54_01B circulated at 4.0%, CRF74_01B at 2.0%, and CRF53_01B and CRF48_01B at 0.7% each. Interestingly, unique HIV-1 genotypes including African subtype G (8.7%), CRF45_cpx (1.3%), CRF02_AG (0.7%) and CRF07_BC (0.7%) from China were detected for the first time in the country. A cluster of subtype G sequences formed a distinct founder sub-lineage within the African strains. In addition, 8.7% (13/149) of HIV-infected donors had unique recombinant forms (URFs) including CRF01_AE/B' (4.7%), B'/C (2.7%) and B'/G (1.3%) recombinants. Detailed analysis identified similar recombinant structures with shared parental strains among the B'/C and B'/G URFs, some of which

  9. Extensive Genetic Diversity of HIV-1 in Incident and Prevalent Infections among Malaysian Blood Donors: Multiple Introductions of HIV-1 Genotypes from Highly Prevalent Countries.

    PubMed

    Chow, Wei Zhen; Bon, Abdul Hamid; Keating, Sheila; Anderios, Fread; Halim, Hazwan Abdul; Takebe, Yutaka; Kamarulzaman, Adeeba; Busch, Michael P; Tee, Kok Keng

    2016-01-01

    Transfusion-transmissible infections including HIV-1 continue to pose major risks for unsafe blood transfusions due to both window phase infections and divergent viruses that may not be detected by donor screening assays. Given the recent emergence of several HIV-1 circulating recombinant forms (CRFs) in high-risk populations in the Southeast Asia region, we investigated the genetic diversity of HIV-1 among the blood donors in Kuala Lumpur, Malaysia. A total of 211 HIV-positive plasma samples detected among 730,188 donations to the National Blood Centre between 2013 and 2014 were provided (90.5% male, median age: 27.0 years old). Recent or long-term infection status at the time of donation was determined using a limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA). HIV-1 gag-pol genes were amplified and sequenced from residual plasma for 149 cases followed by genotype determination using phylogenetic and recombination analyses. Transmitted antiretroviral resistance mutations were not observed among the blood donors, among which 22.7% were classified as recent or incident infections. Major circulating HIV-1 genotypes determined by neighbour-joining phylogenetic inference included CRF01_AE at 40.9% (61/149), CRF33_01B at 21.5% (32/149), and subtype B at 10.1% (15/149). Newly-described CRFs including CRF54_01B circulated at 4.0%, CRF74_01B at 2.0%, and CRF53_01B and CRF48_01B at 0.7% each. Interestingly, unique HIV-1 genotypes including African subtype G (8.7%), CRF45_cpx (1.3%), CRF02_AG (0.7%) and CRF07_BC (0.7%) from China were detected for the first time in the country. A cluster of subtype G sequences formed a distinct founder sub-lineage within the African strains. In addition, 8.7% (13/149) of HIV-infected donors had unique recombinant forms (URFs) including CRF01_AE/B' (4.7%), B'/C (2.7%) and B'/G (1.3%) recombinants. Detailed analysis identified similar recombinant structures with shared parental strains among the B'/C and B'/G URFs, some of which

  10. The Complex Interaction between Methamphetamine Abuse and HIV-1 pathogenesis

    PubMed Central

    Passaro, Ryan Colby; Pandhare, Jui; Qian, Han-Zhu; Dash, Chandravanu

    2016-01-01

    The global HIV/AIDS pandemic has claimed the lives of an estimated 35 million people. A significant barrier for combating this global pandemic is substance use since it is associated with HIV transmission, delayed diagnosis/initiation of therapy, and poor adherence to therapy. Clinical studies also suggest a link between substance use and HIV-disease progression/AIDS-associated mortality. Methamphetamine (METH) use is one of the fastest-growing substance use problems in the world. METH use enhances high-risk sexual behaviors, therefore increases the likelihood of HIV-1 acquisition. METH use is also associated with higher viral loads, immune dysfunction, and antiretroviral resistance. Moreover, METH use has also been correlated with rapid progression to AIDS. However, direct effects of METH on HIV-1 disease progression remains poorly understood because use of METH and other illicit drugs is often associated with reduced/non adherence to ART. Nevertheless, in vitro studies demonstrate that METH increases HIV-1 replication in cell cultures and animal models. Thus, it has been proposed that METH’s potentiating effects on HIV-1 replication may in part contribute to the worsening of HIV-1 pathogenesis. However, our recent data demonstrate that METH inhibits HIV-1 replication in CD4+ T cells and challenges this paradigm. Thus, the goal of this review is to systematically examine the published literature to better understand the complex interaction between METH abuse and HIV-1 disease progression. PMID:25850893

  11. Identification of Siglec-1 null individuals infected with HIV-1.

    PubMed

    Martinez-Picado, Javier; McLaren, Paul J; Erkizia, Itziar; Martin, Maureen P; Benet, Susana; Rotger, Margalida; Dalmau, Judith; Ouchi, Dan; Wolinsky, Steven M; Penugonda, Sudhir; Günthard, Huldrych F; Fellay, Jacques; Carrington, Mary; Izquierdo-Useros, Nuria; Telenti, Amalio

    2016-01-01

    Siglec-1/CD169 is a myeloid-cell surface receptor critical for HIV-1 capture and infection of bystander target cells. To dissect the role of SIGLEC1 in natura, we scan a large population genetic database and identify a loss-of-function variant (Glu88Ter) that is found in ∼1% of healthy people. Exome analysis and direct genotyping of 4,233 HIV-1-infected individuals reveals two Glu88Ter homozygous and 97 heterozygous subjects, allowing the analysis of ex vivo and in vivo consequences of SIGLEC1 loss-of-function. Cells from these individuals are functionally null or haploinsufficient for Siglec-1 activity in HIV-1 capture and trans-infection ex vivo. However, Siglec-1 protein truncation does not have a measurable impact on HIV-1 acquisition or AIDS outcomes in vivo. This result contrasts with the known in vitro functional role of Siglec-1 in HIV-1 trans-infection. Thus, it provides evidence that the classical HIV-1 infectious routes may compensate for the lack of Siglec-1 in fuelling HIV-1 dissemination within infected individuals. PMID:27510803

  12. Identification of Siglec-1 null individuals infected with HIV-1

    PubMed Central

    Martinez-Picado, Javier; McLaren, Paul J.; Erkizia, Itziar; Martin, Maureen P.; Benet, Susana; Rotger, Margalida; Dalmau, Judith; Ouchi, Dan; Wolinsky, Steven M.; Penugonda, Sudhir; Günthard, Huldrych F.; Fellay, Jacques; Carrington, Mary; Izquierdo-Useros, Nuria; Telenti, Amalio

    2016-01-01

    Siglec-1/CD169 is a myeloid-cell surface receptor critical for HIV-1 capture and infection of bystander target cells. To dissect the role of SIGLEC1 in natura, we scan a large population genetic database and identify a loss-of-function variant (Glu88Ter) that is found in ∼1% of healthy people. Exome analysis and direct genotyping of 4,233 HIV-1-infected individuals reveals two Glu88Ter homozygous and 97 heterozygous subjects, allowing the analysis of ex vivo and in vivo consequences of SIGLEC1 loss-of-function. Cells from these individuals are functionally null or haploinsufficient for Siglec-1 activity in HIV-1 capture and trans-infection ex vivo. However, Siglec-1 protein truncation does not have a measurable impact on HIV-1 acquisition or AIDS outcomes in vivo. This result contrasts with the known in vitro functional role of Siglec-1 in HIV-1 trans-infection. Thus, it provides evidence that the classical HIV-1 infectious routes may compensate for the lack of Siglec-1 in fuelling HIV-1 dissemination within infected individuals. PMID:27510803

  13. The Genealogical Population Dynamics of HIV-1 in a Large Transmission Chain: Bridging within and among Host Evolutionary Rates

    PubMed Central

    Vrancken, Bram; Rambaut, Andrew; Suchard, Marc A.; Drummond, Alexei; Baele, Guy; Derdelinckx, Inge; Van Wijngaerden, Eric; Vandamme, Anne-Mieke; Van Laethem, Kristel; Lemey, Philippe

    2014-01-01

    Transmission lies at the interface of human immunodeficiency virus type 1 (HIV-1) evolution within and among hosts and separates distinct selective pressures that impose differences in both the mode of diversification and the tempo of evolution. In the absence of comprehensive direct comparative analyses of the evolutionary processes at different biological scales, our understanding of how fast within-host HIV-1 evolutionary rates translate to lower rates at the between host level remains incomplete. Here, we address this by analyzing pol and env data from a large HIV-1 subtype C transmission chain for which both the timing and the direction is known for most transmission events. To this purpose, we develop a new transmission model in a Bayesian genealogical inference framework and demonstrate how to constrain the viral evolutionary history to be compatible with the transmission history while simultaneously inferring the within-host evolutionary and population dynamics. We show that accommodating a transmission bottleneck affords the best fit our data, but the sparse within-host HIV-1 sampling prevents accurate quantification of the concomitant loss in genetic diversity. We draw inference under the transmission model to estimate HIV-1 evolutionary rates among epidemiologically-related patients and demonstrate that they lie in between fast intra-host rates and lower rates among epidemiologically unrelated individuals infected with HIV subtype C. Using a new molecular clock approach, we quantify and find support for a lower evolutionary rate along branches that accommodate a transmission event or branches that represent the entire backbone of transmitted lineages in our transmission history. Finally, we recover the rate differences at the different biological scales for both synonymous and non-synonymous substitution rates, which is only compatible with the ‘store and retrieve’ hypothesis positing that viruses stored early in latently infected cells

  14. The genealogical population dynamics of HIV-1 in a large transmission chain: bridging within and among host evolutionary rates.

    PubMed

    Vrancken, Bram; Rambaut, Andrew; Suchard, Marc A; Drummond, Alexei; Baele, Guy; Derdelinckx, Inge; Van Wijngaerden, Eric; Vandamme, Anne-Mieke; Van Laethem, Kristel; Lemey, Philippe

    2014-04-01

    Transmission lies at the interface of human immunodeficiency virus type 1 (HIV-1) evolution within and among hosts and separates distinct selective pressures that impose differences in both the mode of diversification and the tempo of evolution. In the absence of comprehensive direct comparative analyses of the evolutionary processes at different biological scales, our understanding of how fast within-host HIV-1 evolutionary rates translate to lower rates at the between host level remains incomplete. Here, we address this by analyzing pol and env data from a large HIV-1 subtype C transmission chain for which both the timing and the direction is known for most transmission events. To this purpose, we develop a new transmission model in a Bayesian genealogical inference framework and demonstrate how to constrain the viral evolutionary history to be compatible with the transmission history while simultaneously inferring the within-host evolutionary and population dynamics. We show that accommodating a transmission bottleneck affords the best fit our data, but the sparse within-host HIV-1 sampling prevents accurate quantification of the concomitant loss in genetic diversity. We draw inference under the transmission model to estimate HIV-1 evolutionary rates among epidemiologically-related patients and demonstrate that they lie in between fast intra-host rates and lower rates among epidemiologically unrelated individuals infected with HIV subtype C. Using a new molecular clock approach, we quantify and find support for a lower evolutionary rate along branches that accommodate a transmission event or branches that represent the entire backbone of transmitted lineages in our transmission history. Finally, we recover the rate differences at the different biological scales for both synonymous and non-synonymous substitution rates, which is only compatible with the 'store and retrieve' hypothesis positing that viruses stored early in latently infected cells preferentially

  15. The genealogical population dynamics of HIV-1 in a large transmission chain: bridging within and among host evolutionary rates.

    PubMed

    Vrancken, Bram; Rambaut, Andrew; Suchard, Marc A; Drummond, Alexei; Baele, Guy; Derdelinckx, Inge; Van Wijngaerden, Eric; Vandamme, Anne-Mieke; Van Laethem, Kristel; Lemey, Philippe

    2014-04-01

    Transmission lies at the interface of human immunodeficiency virus type 1 (HIV-1) evolution within and among hosts and separates distinct selective pressures that impose differences in both the mode of diversification and the tempo of evolution. In the absence of comprehensive direct comparative analyses of the evolutionary processes at different biological scales, our understanding of how fast within-host HIV-1 evolutionary rates translate to lower rates at the between host level remains incomplete. Here, we address this by analyzing pol and env data from a large HIV-1 subtype C transmission chain for which both the timing and the direction is known for most transmission events. To this purpose, we develop a new transmission model in a Bayesian genealogical inference framework and demonstrate how to constrain the viral evolutionary history to be compatible with the transmission history while simultaneously inferring the within-host evolutionary and population dynamics. We show that accommodating a transmission bottleneck affords the best fit our data, but the sparse within-host HIV-1 sampling prevents accurate quantification of the concomitant loss in genetic diversity. We draw inference under the transmission model to estimate HIV-1 evolutionary rates among epidemiologically-related patients and demonstrate that they lie in between fast intra-host rates and lower rates among epidemiologically unrelated individuals infected with HIV subtype C. Using a new molecular clock approach, we quantify and find support for a lower evolutionary rate along branches that accommodate a transmission event or branches that represent the entire backbone of transmitted lineages in our transmission history. Finally, we recover the rate differences at the different biological scales for both synonymous and non-synonymous substitution rates, which is only compatible with the 'store and retrieve' hypothesis positing that viruses stored early in latently infected cells preferentially

  16. Estimation of HIV-1 DNA Level Interfering with Reliability of HIV-1 RNA Quantification Performed on Dried Blood Spots Collected from Successfully Treated Patients.

    PubMed

    Zida, Sylvie; Tuaillon, Edouard; Barro, Makoura; Kwimatouo Lekpa Franchard, Arnaud; Kagoné, Thérèse; Nacro, Boubacar; Ouedraogo, Abdoul Salam; Bolloré, Karine; Sanosyan, Armen; Plantier, Jean-Christophe; Meda, Nicolas; Sangaré, Lassana; Rouzioux, Christine; Rouet, François; Kania, Dramane

    2016-06-01

    The impact of HIV-1 DNA coamplification during HIV-1 RNA quantification on dried blood spots (DBS) was explored. False-positive HIV RNA detection (22/62, 35%) was associated with high HIV-1 DNA levels. Specificity of HIV-1 RNA assays on DBS should be evaluated following manufacturer protocols on samples with HIV-1 DNA levels of ≥1,000 copies/10(6) peripheral blood mononuclear cells. PMID:27008874

  17. Early Combination Antiretroviral Therapy Limits Exposure to HIV-1 Replication and Cell-Associated HIV-1 DNA Levels in Infants

    PubMed Central

    McManus, Margaret; Mick, Eric; Hudson, Richard; Mofenson, Lynne M.; Sullivan, John L.; Somasundaran, Mohan; Luzuriaga, Katherine

    2016-01-01

    The primary aim of this study was to measure HIV-1 persistence following combination antiretroviral therapy (cART) in infants and children. Peripheral blood mononuclear cell (PBMC) HIV-1 DNA was quantified prior to and after 1 year of cART in 30 children, stratified by time of initiation (early, age <3 months, ET; late, age >3 months-2 years, LT). Pre-therapy PBMC HIV-1 DNA levels correlated with pre-therapy plasma HIV-1 levels (r = 0.59, p<0.001), remaining statistically significant (p = 0.002) after adjustment for prior perinatal antiretroviral exposure and age at cART initiation. PBMC HIV-1 DNA declined significantly after 1 year of cART (Overall: -0.91±0.08 log10 copies per million PBMC, p<0.001; ET: -1.04±0.11 log10 DNA copies per million PBMC, p<0.001; LT: -0.74 ±0.13 log10 DNA copies per million PBMC, p<0.001) but rates of decline did not differ significantly between ET and LT. HIV-1 replication exposure over the first 12 months of cART, estimated as area-under-the-curve (AUC) of circulating plasma HIV-1 RNA levels, was significantly associated with PBMC HIV-1 DNA at one year (r = 0.51, p = 0.004). In 21 children with sustained virologic suppression after 1 year of cART, PBMC HIV-1 DNA levels continued to decline between years 1 and 4 (slope -0.21 log10 DNA copies per million PBMC per year); decline slopes did not differ significantly between ET and LT. PBMC HIV-1 DNA levels at 1 year and 4 years of cART correlated with age at cART initiation (1 year: p = 0.04; 4 years: p = 0.03) and age at virologic control (1 and 4 years, p = 0.02). Altogether, these data indicate that reducing exposure to HIV-1 replication and younger age at cART initiation are associated with lower HIV-1 DNA levels at and after one year of age, supporting the concept that HIV-1 diagnosis and cART initiation in infants should occur as early as possible. PMID:27104621

  18. Assessment of Recent HIV-1 Infection by a Line Immunoassay for HIV-1/2 Confirmation

    PubMed Central

    Schüpbach, Jörg; Gebhardt, Martin D; Tomasik, Zuzana; Niederhauser, Christoph; Yerly, Sabine; Bürgisser, Philippe; Matter, Lukas; Gorgievski, Meri; Dubs, Rolf; Schultze, Detlev; Steffen, Ingrid; Andreutti, Corinne; Martinetti, Gladys; Güntert, Bruno; Staub, Roger; Daneel, Synove; Vernazza, Pietro

    2007-01-01

    Background Knowledge of the number of recent HIV infections is important for epidemiologic surveillance. Over the past decade approaches have been developed to estimate this number by testing HIV-seropositive specimens with assays that discriminate the lower concentration and avidity of HIV antibodies in early infection. We have investigated whether this “recency” information can also be gained from an HIV confirmatory assay. Methods and Findings The ability of a line immunoassay (INNO-LIA HIV I/II Score, Innogenetics) to distinguish recent from older HIV-1 infection was evaluated in comparison with the Calypte HIV-1 BED Incidence enzyme immunoassay (BED-EIA). Both tests were conducted prospectively in all HIV infections newly diagnosed in Switzerland from July 2005 to June 2006. Clinical and laboratory information indicative of recent or older infection was obtained from physicians at the time of HIV diagnosis and used as the reference standard. BED-EIA and various recency algorithms utilizing the antibody reaction to INNO-LIA's five HIV-1 antigen bands were evaluated by logistic regression analysis. A total of 765 HIV-1 infections, 748 (97.8%) with complete test results, were newly diagnosed during the study. A negative or indeterminate HIV antibody assay at diagnosis, symptoms of primary HIV infection, or a negative HIV test during the past 12 mo classified 195 infections (26.1%) as recent (≤ 12 mo). Symptoms of CDC stages B or C classified 161 infections as older (21.5%), and 392 patients with no symptoms remained unclassified. BED-EIA ruled 65% of the 195 recent infections as recent and 80% of the 161 older infections as older. Two INNO-LIA algorithms showed 50% and 40% sensitivity combined with 95% and 99% specificity, respectively. Estimation of recent infection in the entire study population, based on actual results of the three tests and adjusted for a test's sensitivity and specificity, yielded 37% for BED-EIA compared to 35% and 33% for the two

  19. Ex vivo gene therapy for HIV-1 treatment

    PubMed Central

    Scherer, Lisa J.; Rossi, John J.

    2011-01-01

    Until recently, progress in ex vivo gene therapy (GT) for human immunodeficiency virus-1 (HIV-1) treatment has been incremental. Long-term HIV-1 remission in a patient who received a heterologous stem cell transplant for acquired immunodeficiency syndrome-related lymphoma from a CCR5−/– donor, even after discontinuation of conventional therapy, has energized the field. We review the status of current approaches as well as future directions in the areas of therapeutic targets, combinatorial strategies, vector design, introduction of therapeutics into stem cells and enrichment/expansion of gene-modified cells. Finally, we discuss recent advances towards clinical application of HIV-1 GT. PMID:21505069

  20. Current Perspectives on HIV-1 Antiretroviral Drug Resistance

    PubMed Central

    Iyidogan, Pinar; Anderson, Karen S.

    2014-01-01

    Current advancements in antiretroviral therapy (ART) have turned HIV-1 infection into a chronic and manageable disease. However, treatment is only effective until HIV-1 develops resistance against the administered drugs. The most recent antiretroviral drugs have become superior at delaying the evolution of acquired drug resistance. In this review, the viral fitness and its correlation to HIV-1 mutation rates and drug resistance are discussed while emphasizing the concept of lethal mutagenesis as an alternative therapy. The development of resistance to the different classes of approved drugs and the importance of monitoring antiretroviral drug resistance are also summarized briefly. PMID:25341668

  1. HIV-1 Replication and the Cellular Eukaryotic Translation Apparatus

    PubMed Central

    Guerrero, Santiago; Batisse, Julien; Libre, Camille; Bernacchi, Serena; Marquet, Roland; Paillart, Jean-Christophe

    2015-01-01

    Eukaryotic translation is a complex process composed of three main steps: initiation, elongation, and termination. During infections by RNA- and DNA-viruses, the eukaryotic translation machinery is used to assure optimal viral protein synthesis. Human immunodeficiency virus type I (HIV-1) uses several non-canonical pathways to translate its own proteins, such as leaky scanning, frameshifting, shunt, and cap-independent mechanisms. Moreover, HIV-1 modulates the host translation machinery by targeting key translation factors and overcomes different cellular obstacles that affect protein translation. In this review, we describe how HIV-1 proteins target several components of the eukaryotic translation machinery, which consequently improves viral translation and replication. PMID:25606970

  2. Gelsolin activity controls efficient early HIV-1 infection

    PubMed Central

    2013-01-01

    Background HIV-1 entry into target lymphocytes requires the activity of actin adaptors that stabilize and reorganize cortical F-actin, like moesin and filamin-A. These alterations are necessary for the redistribution of CD4-CXCR4/CCR5 to one pole of the cell, a process that increases the probability of HIV-1 Envelope (Env)-CD4/co-receptor interactions and that generates the tension at the plasma membrane necessary to potentiate fusion pore formation, thereby favouring early HIV-1 infection. However, it remains unclear whether the dynamic processing of F-actin and the amount of cortical actin available during the initial virus-cell contact are required to such events. Results Here we show that gelsolin restructures cortical F-actin during HIV-1 Env-gp120-mediated signalling, without affecting cell-surface expression of receptors or viral co-receptor signalling. Remarkably, efficient HIV-1 Env-mediated membrane fusion and infection of permissive lymphocytes were impaired when gelsolin was either overexpressed or silenced, which led to a loss or gain of cortical actin, respectively. Indeed, HIV-1 Env-gp120-induced F-actin reorganization and viral receptor capping were impaired under these experimental conditions. Moreover, gelsolin knockdown promoted HIV-1 Env-gp120-mediated aberrant pseudopodia formation. These perturbed-actin events are responsible for the inhibition of early HIV-1 infection. Conclusions For the first time we provide evidence that through its severing of cortical actin, and by controlling the amount of actin available for reorganization during HIV-1 Env-mediated viral fusion, entry and infection, gelsolin can constitute a barrier that restricts HIV-1 infection of CD4+ lymphocytes in a pre-fusion step. These findings provide important insights into the complex molecular and actin-associated dynamics events that underlie early viral infection. Thus, we propose that gelsolin is a new factor that can limit HIV-1 infection acting at a pre-fusion step

  3. Towards an HIV-1 cure: measuring the latent reservoir

    PubMed Central

    Bruner, Katherine M.; Hosmane, Nina N.; Siliciano, Robert F.

    2015-01-01

    The latent reservoir of HIV-1 in resting memory CD4+ T cells serves as a major barrier to curing HIV-1 infection. While many PCR- and culture-based assays have been used to measure the size of the latent reservoir, correlation between results of different assays is poor and recent studies indicate that no available assay provides an accurate measurement of reservoir size. The discrepancies between assays are a hurdle to clinical trials that aim to measure the efficacy of HIV-1 eradication strategies. Here we describe the advantages and disadvantages of various approaches to measure the latent reservoir. PMID:25747663

  4. MicroRNAs and HIV-1: Complex Interactions*

    PubMed Central

    Klase, Zachary; Houzet, Laurent; Jeang, Kuan-Teh

    2012-01-01

    RNAi plays important roles in many biological processes, including cellular defense against viral infection. Components of the RNAi machinery are widely conserved in plants and animals. In mammals, microRNAs (miRNAs) represent an abundant class of cell encoded small noncoding RNAs that participate in RNAi-mediated gene silencing. Here, findings that HIV-1 replication in cells can be regulated by miRNAs and that HIV-1 infection of cells can alter cellular miRNA expression are reviewed. Lessons learned from and questions outstanding about the complex interactions between HIV-1 and cellular miRNAs are discussed. PMID:23043098

  5. Human herpes virus-6 increases HIV-1 expression in co-infected T cells via nuclear factors binding to the HIV-1 enhancer.

    PubMed Central

    Ensoli, B; Lusso, P; Schachter, F; Josephs, S F; Rappaport, J; Negro, F; Gallo, R C; Wong-Staal, F

    1989-01-01

    Human Herpes virus-6 (HHV-6) can co-infect with HIV-1 human CD4+ T-cells, leading to accelerated cell death, and factors in HHV-6-infected cells stimulate HIV-1 LTR directed gene expression. In this study, we have examined the mechanism of HIV-1 activation by HHV-6 and localized the cis-acting sequences of HIV-1 LTR responsive to trans-activation. Increased HIV-1 LTR directed gene expression is obtained in HIV-1 infected cells co-infected with HHV-6, or in HHV-6 infected cells co-transfected with the HIV-1 tat gene. Parallel increases of HIV-1-specific transcripts are seen by in situ hybridization in HHV-6/HIV-1 doubly infected cells as compared to single HIV-1 infection. Similarly, infection by HHV-6 increases the steady-state level of HIV-1 LTR mRNA that parallels CAT enzymatic activity, suggesting a transcriptional and/or post-transcriptional activation. Sequences necessary for HIV-1 LTR activation by HHV-6 are distinct from those required for that tat response and map to a region of the HIV-1 LTR from -103 to -48. The HIV-1 enhancer sequence (-105 to -80) is sufficient to confer HHV-6 inducibility to a heterologous promoter, and nuclear protein(s) activated or induced by HHV-6 infection specifically bind to the NF kappa B motifs of the HIV-1 enhancer region.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:2573513

  6. Abasic Phosphorothioate Oligomers Inhibit HIV-1 Reverse Transcription and Block Virus Transmission across Polarized Ectocervical Organ Cultures

    PubMed Central

    Fraietta, Joseph A.; Mueller, Yvonne M.; Lozenski, Karissa L.; Ratner, Deena; Boesteanu, Alina C.; Hancock, Aidan S.; Lackman-Smith, Carol; Zentner, Isaac J.; Chaiken, Irwin M.; Chung, Suhman; LeGrice, Stuart F. J.; Snyder, Beth A.; Mankowski, Marie K.; Jones, Natalie M.; Hope, Jennifer L.; Gupta, Phalguni; Anderson, Sharon H.; Wigdahl, Brian

    2014-01-01

    In the absence of universally available antiretroviral (ARV) drugs or a vaccine against HIV-1, microbicides may offer the most immediate hope for controlling the AIDS pandemic. The most advanced and clinically effective microbicides are based on ARV agents that interfere with the earliest stages of HIV-1 replication. Our objective was to identify and characterize novel ARV-like inhibitors, as well as demonstrate their efficacy at blocking HIV-1 transmission. Abasic phosphorothioate 2′ deoxyribose backbone (PDB) oligomers were evaluated in a variety of mechanistic assays and for their ability to inhibit HIV-1 infection and virus transmission through primary human cervical mucosa. Cellular and biochemical assays were used to elucidate the antiviral mechanisms of action of PDB oligomers against both lab-adapted and primary CCR5- and CXCR4-utilizing HIV-1 strains, including a multidrug-resistant isolate. A polarized cervical organ culture was used to test the ability of PDB compounds to block HIV-1 transmission to primary immune cell populations across ectocervical tissue. The antiviral activity and mechanisms of action of PDB-based compounds were dependent on oligomer size, with smaller molecules preventing reverse transcription and larger oligomers blocking viral entry. Importantly, irrespective of molecular size, PDBs potently inhibited virus infection and transmission within genital tissue samples. Furthermore, the PDB inhibitors exhibited excellent toxicity and stability profiles and were found to be safe for vaginal application in vivo. These results, coupled with the previously reported intrinsic anti-inflammatory properties of PDBs, support further investigations in the development of PDB-based topical microbicides for preventing the global spread of HIV-1. PMID:25224013

  7. Comparison of the Cepheid GeneXpert and Abbott M2000 HIV-1 real time molecular assays for monitoring HIV-1 viral load and detecting HIV-1 infection.

    PubMed

    Ceffa, Susanna; Luhanga, Richard; Andreotti, Mauro; Brambilla, Davide; Erba, Fulvio; Jere, Haswel; Mancinelli, Sandro; Giuliano, Marina; Palombi, Leonardo; Marazzi, Maria Cristina

    2016-03-01

    Assessing treatment efficacy and early infant diagnosis (EID) are critical issues in HIV disease management. Point-of-care assays may greatly increase the possibility to access laboratory monitoring also in rural areas. Recently two new laboratory tests have been developed by Cepheid (Sunnyvale, California) the Xpert HIV-1 Viral Load for viral load determination and the Xpert HIV-1 Qualitative for early infant diagnosis. We conducted a study in Blantyre, Malawi, comparing the 2 methods versus the Abbott real time quantitative and qualitative assays, for viral load and EID respectively. We tested 300 plasma samples for viral load determination and 200 samples for infant diagnosis. HIV-1 RNA values of the 274 samples quantified by both assays were highly correlated (Pearson r=0.95, R(2)=0.90). In 90.9% of the cases the two methods were concordant in defining the HIV-1 RNA levels as detectable or undetectable. For EID, the Xpert HIV-1 Qualitative assay yielded the same identical results as the Abbott assay. Both the quantitative and the qualitative Xpert assays are promising tools to monitor treatment efficacy in HIV patients receiving treatment and for early diagnosis in HIV-exposed infants. PMID:26709099

  8. Comparison of a conventional HIV 1/2 line immunoassay with a rapid confirmatory HIV 1/2 assay.

    PubMed

    Tinguely, Caroline; Schild-Spycher, Therese; Bahador, Zahra; Gowland, Peter; Stolz, Martin; Niederhauser, Christoph

    2014-09-01

    The performance of the rapid confirmatory HIV 1/2 assay Geenius was compared with the conventional HIV 1/2 line immunoblot (INNO-LIA HIV I/II Score). One hundred HIV 1/2 confirmed positive samples from donors and patients and 136 negative screening samples from blood donors were evaluated with both assays. A 20 member performance panel consisting of different HIV 1 and 2 subtypes was also analysed. Ninety-nine of the confirmed HIV positive samples were positive with both assays. One sample was positive with the INNO-LIA HIV I/II Score but indeterminate with the Geenius HIV 1/2. From 136 negative blood donor samples (negative with a combo HIV assay and a highly sensitive ID-NAT), 125 were concordant negative. Six and five samples were incorrectly indeterminate with the INNO-LIA HIV I/II Score and the Geenius HIV 1/2, respectively. One sample was weak positive with the INNO-LIA HIV I/II Score but negative with the Geenius HIV 1/2. The 20 member performance showed equivalent results with both assays. The rapid assay showed a comparable sensitivity and specificity for confirmation for positive and negative HIV donor and patient samples as well for a 20 member performance panel.

  9. The 73 kDa subunit of the CPSF complex binds to the HIV-1 LTR promoter and functions as a negative regulatory factor that is inhibited by the HIV-1 Tat protein.

    PubMed

    de la Vega, Laureano; Sánchez-Duffhues, Gonzalo; Fresno, Manuel; Schmitz, M Lienhard; Muñoz, Eduardo; Calzado, Marco A

    2007-09-14

    Gene expression in eukaryotes requires the post-transcriptional cleavage of mRNA precursors into mature mRNAs. The cleavage and polyadenylation specificity factor (CPSF) is critical for this process and its 73 kDa subunit (CPSF-73) mediates cleavage coupled to polyadenylation and histone pre-mRNA processing. Using CPSF-73 over-expression and siRNA-mediated knockdown experiments, this study identifies CPSF-73 as an important regulatory protein that represses the basal transcriptional activity of the HIV-1 LTR promoter. Similar results were found with over-expression of the CPSF-73 homologue RC-68, but not with CPSF 100 kDa subunit (CPSF-100) and RC-74. Chromatin immunoprecipitation assays revealed the physical interaction of CPSF-73 with the HIV-1 LTR promoter. Further experiments revealed indirect CPSF-73 binding to the region between -275 to -110 within the 5' upstream region. Functional assays revealed the importance for the 5' upstream region (-454 to -110) of the LTR for CPSF-73-mediated transcription repression. We also show that HIV-1 Tat protein interacts with CPSF-73 and counteracts its repressive activity on the HIV-1 LTR promoter. Our results clearly show a novel function for CPSF-73 and add another candidate protein for explaining the molecular mechanisms underlying HIV-1 latency.

  10. Recent developments in the search for a cure for HIV-1 infection: targeting the latent reservoir for HIV-1.

    PubMed

    Siliciano, Janet D; Siliciano, Robert F

    2014-07-01

    HIV-1 infection can now be readily controlled with combination antiretroviral therapy. However, the virus persists indefinitely in a stable latent reservoir in resting CD4(+) T cells. This reservoir generally prevents cure of the infection with combination antiretroviral therapy alone. However, several recent cases of potential HIV-1 cure have generated renewed optimism. Here we review these cases and consider new developments in our understanding of the latent reservoir. In addition, we consider clinical aspects of curative strategies to provide a more realistic picture of what a generally applicable cure for HIV-1 infection is likely to entail.

  11. Enrichment of intersubtype HIV-1 recombinants in a dual infection system using HIV-1 strain-specific siRNAs

    PubMed Central

    2011-01-01

    Background Intersubtype HIV-1 recombinants in the form of unique or stable circulating recombinants forms (CRFs) are responsible for over 20% of infections in the worldwide epidemic. Mechanisms controlling the generation, selection, and transmission of these intersubtype HIV-1 recombinants still require further investigation. All intersubtype HIV-1 recombinants are generated and evolve from initial dual infections, but are difficult to identify in the human population. In vitro studies provide the most practical system to study mechanisms, but the recombination rates are usually very low in dual infections with primary HIV-1 isolates. This study describes the use of HIV-1 isolate-specific siRNAs to enrich intersubtype HIV-1 recombinants and inhibit the parental HIV-1 isolates from a dual infection. Results Following a dual infection with subtype A and D primary HIV-1 isolates and two rounds of siRNA treatment, nearly 100% of replicative virus was resistant to a siRNA specific for an upstream target sequence in the subtype A envelope (env) gene as well as a siRNA specific for a downstream target sequence in the subtype D env gene. Only 20% (10/50) of the replicating virus had nucleotide substitutions in the siRNA-target sequence whereas the remaining 78% (39/50) harbored a recombination breakpoint that removed both siRNA target sequences, and rendered the intersubtype D/A recombinant virus resistant to the dual siRNA treatment. Since siRNAs target the newly transcribed HIV-1 mRNA, the siRNAs only enrich intersubtype env recombinants and do not influence the recombination process during reverse transcription. Using this system, a strong bias is selected for recombination breakpoints in the C2 region, whereas other HIV-1 env regions, most notably the hypervariable regions, were nearly devoid of intersubtype recombination breakpoints. Sequence conservation plays an important role in selecting for recombination breakpoints, but the lack of breakpoints in many conserved

  12. Rethinking the Heterosexual Infectivity of HIV-1: A Systematic Review and Meta-analysis

    PubMed Central

    Powers, Kimberly A.; Poole, Charles; Pettifor, Audrey E.; Cohen, Myron S.

    2009-01-01

    Background Studies of cumulative HIV incidence suggest that co-factors such as genital ulcer disease (GUD), HIV disease stage, and circumcision influence HIV transmission; however, the heterosexual infectivity of HIV-1 is commonly cited as a fixed value (∼0·001, or 1 transmission per thousand contacts). We sought to estimate transmission co-factor effects on the heterosexual infectivity of HIV-1 and to quantify the extent to which study methods have affected infectivity estimates. Methods We conducted a systematic search (through April 2008) of PubMed, Web of Science, and relevant bibliographies to identify articles estimating the heterosexual infectivity of HIV-1. We used meta-regression and stratified random-effects meta-analysis to assess differences in infectivity by co-factors and study methods. Findings Infectivity estimates were extremely heterogeneous, ranging from zero transmissions after more than 100 penile-vaginal contacts in some sero-discordant couples to one transmission for every 3·1 episodes of heterosexual anal intercourse. Estimates were only weakly associated with study methods. Infectivity differences (95% confidence intervals), expressed as number of transmissions per 1000 contacts, were 8 (0-16) comparing uncircumcised to circumcised male susceptibles, 6 (3-9) comparing susceptible individuals with and without GUD, 2 (1-3) comparing late-stage to mid-stage index cases, and 3 (0-5) comparing early-stage to mid-stage index cases. Interpretation A single value for the heterosexual infectivity of HIV-1 fails to reflect the variation associated with important co-factors. The commonly cited value of ∼0·001 was estimated among stable couples with low prevalences of high-risk co-factors, and represents a lower bound. Co-factor effects are important to include in epidemic models, policy considerations, and prevention messages. PMID:18684670

  13. HIV-1 envelope replication and α4β7 utilization among newly infected subjects and their corresponding heterosexual partners

    PubMed Central

    2013-01-01

    Background Previous studies suggest that active selection limits the number of HIV-1 variants acquired by a newly infected individual from the diverse variants circulating in the transmitting partner. We compared HIV-1 envelopes from 9 newly infected subjects and their linked transmitting partner to explore potential mechanisms for selection. Results Recipient virus envelopes had significant genotypic differences compared to those present in the transmitting partner. Recombinant viruses incorporating pools of recipient and transmitter envelopes showed no significant difference in their sensitivity to receptor and fusion inhibitors, suggesting they had relatively similar entry capacity in the presence of low CD4 and CCR5 levels. Aggregate results in primary cells from up to 4 different blood or skin donors showed that viruses with envelopes from the transmitting partner as compared to recipient envelopes replicated more efficiently in CD4+ T cells, monocyte derived dendritic cell (MDDC) – CD4+ T cell co-cultures, Langerhans cells (LCs) – CD4+ T cell co-cultures and CD4+ T cells expressing high levels of the gut homing receptor, α4β7, and demonstrated greater binding to α4β7 high / CD8+ T cells. These transmitter versus recipient envelope virus phenotypic differences, however, were not always consistent among the primary cells from all the different blood or skin donation volunteers. Conclusion Although genotypically unique variants are present in newly infected individuals compared to the diverse swarm circulating in the chronically infected transmitting partner, replication in potential early target cells and receptor utilization either do not completely dictate this genetic selection, or these potential transmission phenotypes are lost very soon after HIV-1 acquisition. PMID:24369910

  14. High recombination potential of subtype A HIV-1.

    PubMed

    Nikolaitchik, Olga; Keele, Brandon; Gorelick, Robert; Alvord, W Gregory; Mazurov, Dmitriy; Pathak, Vinay K; Hu, Wei-Shau

    2015-10-01

    Recombination can assort polymorphic alleles to increase diversity in the HIV-1 population. To better understand the recombination potential of subtype A HIV-1, we generated viruses containing sequences from two variants circulating in Russia and analyzed the polymerase gene (pol) of the recombinants after one round of HIV-1 replication using single-genome sequencing. We observed that recombination occurred throughout pol and could easily assort alleles containing mutations that conferred resistance to currently approved antivirals. We measured the recombination rate in various regions of pol including a G-rich region that has been previously proposed to be a recombination hot spot. Our study does not support a recombination hot spot in this G-rich region. Importantly, of the 58 proviral sequences containing crossover event(s) in pol, we found that each sequence was a unique genotype indicating that recombination is a powerful genetic mechanism in assorting the genomes of subtype A HIV-1 variants.

  15. Detection of HIV-1 p24 at Attomole Level by Ultrasensitive ELISA with Thio-NAD Cycling

    PubMed Central

    Nakatsuma, Akira; Kaneda, Mugiho; Kodama, Hiromi; Morikawa, Mika; Watabe, Satoshi; Nakaishi, Kazunari; Yamashita, Masakane; Yoshimura, Teruki; Miura, Toshiaki; Ninomiya, Masaki; Ito, Etsuro

    2015-01-01

    To reduce the window period between HIV-1 infection and the ability to diagnose it, a fourth-generation immunoassay including the detection of HIV-1 p24 antigen has been developed. However, because the commercially available systems for this assay use special, high-cost instruments to measure, for example, chemiluminescence, it is performed only by diagnostics companies and hub hospitals. To overcome this limitation, we applied an ultrasensitive ELISA coupled with a thio-NAD cycling, which is based on a usual enzyme immunoassay without special instruments, to detect HIV-1 p24. The p24 detection limit by our ultrasensitive ELISA was 0.0065 IU/assay (i.e., ca. 10-18 moles/assay). Because HIV-1 p24 antigen is thought to be present in the virion in much greater numbers than viral RNA copies, the value of 10-18 moles of the p24/assay corresponds to ca. 103 copies of the HIV-1 RNA/assay. That is, our ultrasensitive ELISA is chasing the detection limit (102 copies/assay) obtained by PCR-based nucleic acid testing (NAT) with a margin of only one different order. Further, the detection limit by our ultrasensitive ELISA is less than that mandated for a CE-marked HIV antigen/antibody assay. An additional recovery test using blood supported the reliability of our ultrasensitive ELISA. PMID:26098695

  16. Evaluation of the Aptima(®) HIV-1 Quant Dx assay for HIV-1 RNA viral load detection and quantitation in plasma of HIV-1-infected individuals: A comparison with Abbott RealTime HIV-1 assay.

    PubMed

    Amendola, Alessandra; Pisciotta, Maria; Aleo, Loredana; Ferraioli, Valeria; Angeletti, Claudio; Capobianchi, Maria Rosaria

    2016-09-01

    The Hologic Aptima(®) HIV-1 Quant Dx assay (Aptima HIV) is a real-time transcription-mediated amplification method CE-approved for use in diagnosis and monitoring of HIV-1 infection. The analytical performance of this new assay was compared to the FDA-approved Abbott RealTime HIV-1 (RealTime). The evaluation was performed using 220 clinical plasma samples, the WHO 3rd HIV-1 International Standard, and the QCMD HIV-1 RNA EQA. Concordance on qualitative results, correlation between quantitative results, accuracy, and reproducibility of viral load data were analyzed. The ability to measure HIV-1 subtypes was assessed on the second WHO International Reference Preparation Panel for HIV-1 Subtypes. With clinical samples, inter-assay agreement for qualitative results was high (91.8%) with Cohen's kappa statistic equal to 0.836. For samples with quantitative results in both assays (n = 93), Lin's concordance correlation coefficient was 0.980 (P < 0.0001) and mean differences of measurement, conducted according to Bland-Altman method, was low (0.115 log10  copies/ml). The Aptima HIV quantified the WHO 3rd HIV-1 International Standard diluted from 2000 to 31 cp/ml (5,700-88 IU/ml) at expected values with excellent linearity (R(2)  > 0.970) and showed higher sensitivity compared to RealTime being able to detect HIV-1 RNA in 10 out of 10 replicates containing down to 7 cp/ml (20 IU/ml). Reproducibility was very high, even at low HIV-1 RNA values. The Aptima HIV was able to detect and accurately quantify all the main HIV-1 subtypes in both reference panels and clinical samples. Besides excellent performance, Aptima HIV shows full automation, ease of use, and improved workflow compared to RealTime. J. Med. Virol. 88:1535-1544, 2016. © 2016 Wiley Periodicals, Inc.

  17. Evaluation of the Aptima(®) HIV-1 Quant Dx assay for HIV-1 RNA viral load detection and quantitation in plasma of HIV-1-infected individuals: A comparison with Abbott RealTime HIV-1 assay.

    PubMed

    Amendola, Alessandra; Pisciotta, Maria; Aleo, Loredana; Ferraioli, Valeria; Angeletti, Claudio; Capobianchi, Maria Rosaria

    2016-09-01

    The Hologic Aptima(®) HIV-1 Quant Dx assay (Aptima HIV) is a real-time transcription-mediated amplification method CE-approved for use in diagnosis and monitoring of HIV-1 infection. The analytical performance of this new assay was compared to the FDA-approved Abbott RealTime HIV-1 (RealTime). The evaluation was performed using 220 clinical plasma samples, the WHO 3rd HIV-1 International Standard, and the QCMD HIV-1 RNA EQA. Concordance on qualitative results, correlation between quantitative results, accuracy, and reproducibility of viral load data were analyzed. The ability to measure HIV-1 subtypes was assessed on the second WHO International Reference Preparation Panel for HIV-1 Subtypes. With clinical samples, inter-assay agreement for qualitative results was high (91.8%) with Cohen's kappa statistic equal to 0.836. For samples with quantitative results in both assays (n = 93), Lin's concordance correlation coefficient was 0.980 (P < 0.0001) and mean differences of measurement, conducted according to Bland-Altman method, was low (0.115 log10  copies/ml). The Aptima HIV quantified the WHO 3rd HIV-1 International Standard diluted from 2000 to 31 cp/ml (5,700-88 IU/ml) at expected values with excellent linearity (R(2)  > 0.970) and showed higher sensitivity compared to RealTime being able to detect HIV-1 RNA in 10 out of 10 replicates containing down to 7 cp/ml (20 IU/ml). Reproducibility was very high, even at low HIV-1 RNA values. The Aptima HIV was able to detect and accurately quantify all the main HIV-1 subtypes in both reference panels and clinical samples. Besides excellent performance, Aptima HIV shows full automation, ease of use, and improved workflow compared to RealTime. J. Med. Virol. 88:1535-1544, 2016. © 2016 Wiley Periodicals, Inc. PMID:26864171

  18. HLA-C Downmodulation by HIV-1 Vpu.

    PubMed

    Barker, Edward; Evans, David T

    2016-05-11

    It is widely held that HIV-1 Nef downmodulates HLA-A and -B to protect infected cells from CD8(+) T cells but leaves HLA-C on the cell surface to inhibit NK cells. In this issue of Cell Host & Microbe, Apps et al. (2016) revise this model by showing that the Vpu protein of primary HIV-1 isolates downmodulate HLA-C.

  19. High HIV-1 Genetic Diversity in Patients from Northern Brazil.

    PubMed

    da Costa, Carolina Marinho; Costa de Oliveira, Cintia Mara; Chehuan de Melo, Yonne Francis; Delatorre, Edson; Bello, Gonzalo; Couto-Fernandez, Jose Carlos

    2016-09-01

    The HIV-1 epidemic in Brazil is driven by subtypes B, F1, and C and recombinants forms among those subtypes. The distribution of HIV-1 subtypes, however, may vary across different Brazilian regions and the molecular epidemiologic profile in Northern Brazil remains poorly explored. HIV-1 pol sequences were obtained from 305 patients failing antiretroviral therapy followed at outpatient clinics from five Northern Brazilian states. The most prevalent HIV-1 clade observed in the Northern Brazilian region was subtype B (81%), followed by BF1 recombinants (10%), subtype F1 (4%), subtype C (3%), BC recombinants (2%), and BU recombinants (1%). Although HIV-1 subtype B was the predominant HIV-1 clade in Northern Brazil, its prevalence greatly varies among different states, ranging from 63% in Rondônia to 92% in Acre. Among the 37 HIV-1 recombinant sequences detected in the Northern Brazilian region, nine (24%) displayed a unique recombinant form structure, five (14%) a CRF28/29_BF-like structure, and four (11%) a CRF31_BC-like structure. Two other BF1 recombinant patterns were identified in 16 (43%) and three (8%) samples that may correspond to two potentially new CRFs_BF characteristic of the Northern region. This study reveals that despite the low spatial connectivity with other Brazilian regions, the genetic complexity of the HIV-1 epidemic in Northern Brazil is very high and that the molecular epidemiologic pattern may vary across different northern states, reflecting a complex epidemic with multiple independent viral introductions into this Brazilian region. PMID:27091699

  20. High HIV-1 Genetic Diversity in Patients from Northern Brazil.

    PubMed

    da Costa, Carolina Marinho; Costa de Oliveira, Cintia Mara; Chehuan de Melo, Yonne Francis; Delatorre, Edson; Bello, Gonzalo; Couto-Fernandez, Jose Carlos

    2016-09-01

    The HIV-1 epidemic in Brazil is driven by subtypes B, F1, and C and recombinants forms among those subtypes. The distribution of HIV-1 subtypes, however, may vary across different Brazilian regions and the molecular epidemiologic profile in Northern Brazil remains poorly explored. HIV-1 pol sequences were obtained from 305 patients failing antiretroviral therapy followed at outpatient clinics from five Northern Brazilian states. The most prevalent HIV-1 clade observed in the Northern Brazilian region was subtype B (81%), followed by BF1 recombinants (10%), subtype F1 (4%), subtype C (3%), BC recombinants (2%), and BU recombinants (1%). Although HIV-1 subtype B was the predominant HIV-1 clade in Northern Brazil, its prevalence greatly varies among different states, ranging from 63% in Rondônia to 92% in Acre. Among the 37 HIV-1 recombinant sequences detected in the Northern Brazilian region, nine (24%) displayed a unique recombinant form structure, five (14%) a CRF28/29_BF-like structure, and four (11%) a CRF31_BC-like structure. Two other BF1 recombinant patterns were identified in 16 (43%) and three (8%) samples that may correspond to two potentially new CRFs_BF characteristic of the Northern region. This study reveals that despite the low spatial connectivity with other Brazilian regions, the genetic complexity of the HIV-1 epidemic in Northern Brazil is very high and that the molecular epidemiologic pattern may vary across different northern states, reflecting a complex epidemic with multiple independent viral introductions into this Brazilian region.

  1. Engineering T Cells to Functionally Cure HIV-1 Infection.

    PubMed

    Leibman, Rachel S; Riley, James L

    2015-07-01

    Despite the ability of antiretroviral therapy to minimize human immunodeficiency virus type 1 (HIV-1) replication and increase the duration and quality of patients' lives, the health consequences and financial burden associated with the lifelong treatment regimen render a permanent cure highly attractive. Although T cells play an important role in controlling virus replication, they are themselves targets of HIV-mediated destruction. Direct genetic manipulation of T cells for adoptive cellular therapies could facilitate a functional cure by generating HIV-1-resistant cells, redirecting HIV-1-specific immune responses, or a combination of the two strategies. In contrast to a vaccine approach, which relies on the production and priming of HIV-1-specific lymphocytes within a patient's own body, adoptive T-cell therapy provides an opportunity to customize the therapeutic T cells prior to administration. However, at present, it is unclear how to best engineer T cells so that sustained control over HIV-1 replication can be achieved in the absence of antiretrovirals. This review focuses on T-cell gene-engineering and gene-editing strategies that have been performed in efforts to inhibit HIV-1 replication and highlights the requirements for a successful gene therapy-mediated functional cure.

  2. Potent inhibition of HIV-1 replication by a Tat mutant.

    PubMed

    Meredith, Luke W; Sivakumaran, Haran; Major, Lee; Suhrbier, Andreas; Harrich, David

    2009-11-10

    Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.

  3. Quantitative Phosphoproteomics Reveals Extensive Cellular Reprogramming During HIV-1 Entry

    PubMed Central

    Wojcechowskyj, Jason A.; Didigu, Chuka A.; Lee, Jessica Y.; Parrish, Nicholas F.; Sinha, Rohini; Hahn, Beatrice H.; Bushman, Frederic D.; Jensen, Shane T.; Seeholzer, Steven H.; Doms, Robert W.

    2014-01-01

    SUMMARY Receptor engagement by HIV-1 during host cell entry activates signaling pathways that can reprogram the cell for optimal viral replication. To obtain a global view of the signaling events induced during HIV-1 entry, we conducted a quantitative phosphoproteomics screen of primary human CD4+ T cell after infection with an HIV-1 strain that engages the receptors CD4 and CXCR4. We quantified 1,757 phosphorylation sites with high stringency. The abundance of 239 phosphorylation sites from 175 genes, including several proteins in pathways known to be impacted by HIV-receptor binding, changed significantly within a minute after HIV-1 exposure. Several previously uncharacterized HIV-1 host factors were also identified and confirmed through RNAi depletion studies. Surprisingly, 5 serine/arginine-rich (SR)-proteins involved in mRNA splicing, including the splicing factor SRm300 (SRRM2) were differentially phosophorylated. Mechanistic studies with SRRM2 suggest that HIV-1 modulates host cell alternative splicing machinery during entry in order to facilitate virus replication and release. PMID:23684312

  4. Identification of potent maturation inhibitors against HIV-1 clade C

    PubMed Central

    Timilsina, Uddhav; Ghimire, Dibya; Timalsina, Bivek; Nitz, Theodore J.; Wild, Carl T.; Freed, Eric O.; Gaur, Ritu

    2016-01-01

    Antiretroviral therapy has led to a profound improvement in the clinical care of HIV-infected patients. However, drug tolerability and the evolution of drug resistance have limited treatment options for many patients. Maturation inhibitors are a new class of antiretroviral agents for treatment of HIV-1. They act by interfering with the maturation of the virus by blocking the last step in Gag processing: the cleavage of the capsid-spacer peptide 1 (CA-SP1) intermediate to mature CA by the viral protease (PR). The first-in-class maturation inhibitor bevirimat (BVM) failed against a subset of HIV-1 isolates in clinical trials due to polymorphisms present in the CA-SP1 region of the Gag protein. Sequence analysis indicated that these polymorphisms are more common in non-clade B strains of HIV-1 such as HIV-1 clade C. Indeed, BVM was found to be ineffective against HIV-1 clade C molecular clones tested in this study. A number of BVM analogs were synthesized by chemical modifications at the C-28 position to improve its activity. The new BVM analogs displayed potent activity against HIV-1 clade B and C and also reduced infectivity of the virus. This study identifies novel and broadly active BVM analogs that may ultimately demonstrate efficacy in the clinic. PMID:27264714

  5. Engineering T Cells to Functionally Cure HIV-1 Infection

    PubMed Central

    Leibman, Rachel S; Riley, James L

    2015-01-01

    Despite the ability of antiretroviral therapy to minimize human immunodeficiency virus type 1 (HIV-1) replication and increase the duration and quality of patients' lives, the health consequences and financial burden associated with the lifelong treatment regimen render a permanent cure highly attractive. Although T cells play an important role in controlling virus replication, they are themselves targets of HIV-mediated destruction. Direct genetic manipulation of T cells for adoptive cellular therapies could facilitate a functional cure by generating HIV-1–resistant cells, redirecting HIV-1–specific immune responses, or a combination of the two strategies. In contrast to a vaccine approach, which relies on the production and priming of HIV-1–specific lymphocytes within a patient's own body, adoptive T-cell therapy provides an opportunity to customize the therapeutic T cells prior to administration. However, at present, it is unclear how to best engineer T cells so that sustained control over HIV-1 replication can be achieved in the absence of antiretrovirals. This review focuses on T-cell gene-engineering and gene-editing strategies that have been performed in efforts to inhibit HIV-1 replication and highlights the requirements for a successful gene therapy–mediated functional cure. PMID:25896251

  6. Histone acetyltransferases regulate HIV-1 enhancer activity in vitro

    PubMed Central

    Sheridan, Philip L.; Mayall, Timothy P.; Verdin, Eric; Jones, Katherine A.

    1997-01-01

    Specific inhibitors of histone deacetylase, such as trichostatin A (TSA) and trapoxin (TPX), are potent inducers of HIV-1 transcription in latently infected T-cell lines. Activation of the integrated HIV-1 promoter is accompanied by the loss or rearrangement of a positioned nucleosome (nuc-1) near the viral RNA start site. Here we show that TSA strongly induces HIV-1 transcription on chromatin in vitro, concomitant with an enhancer factor-assisted increase in the level of acetylated histone H4. TSA treatment, however, did not detectably alter enhancer factor binding or the positioning of nuc-1 on the majority of the chromatin templates indicating that protein acetylation and chromatin remodeling may be limiting steps that occur only on transcriptionally competent templates, or that remodeling of nuc-1 requires additional factors. To assess the number of active chromatin templates in vitro, transcription was limited to a single round with low levels of the detergent Sarkosyl. Remarkably, HIV-1 transcription on chromatin was found to arise from a small number of active templates that can each support nearly 100 rounds of transcription, and TSA increased the number of active templates in each round. In contrast, transcription on naked DNA was limited to only a few rounds and was not responsive to TSA. We conclude that HIV-1 enhancer complexes greatly facilitate transcription reinitiation on chromatin in vitro, and act at a limiting step to promote the acetylation of histones or other transcription factors required for HIV-1 enhancer activity. PMID:9407026

  7. Negative Feedback Regulation of HIV-1 by Gene Editing Strategy.

    PubMed

    Kaminski, Rafal; Chen, Yilan; Salkind, Julian; Bella, Ramona; Young, Won-Bin; Ferrante, Pasquale; Karn, Jonathan; Malcolm, Thomas; Hu, Wenhui; Khalili, Kamel

    2016-01-01

    The CRISPR/Cas9 gene editing method is comprised of the guide RNA (gRNA) to target a specific DNA sequence for cleavage and the Cas9 endonuclease for introducing breaks in the double-stranded DNA identified by the gRNA. Co-expression of both a multiplex of HIV-1-specific gRNAs and Cas9 in cells results in the modification and/or excision of the segment of viral DNA, leading to replication-defective virus. In this study, we have personalized the activity of CRISPR/Cas9 by placing the gene encoding Cas9 under the control of a minimal promoter of HIV-1 that is activated by the HIV-1 Tat protein. We demonstrate that functional activation of CRISPR/Cas9 by Tat during the course of viral infection excises the designated segment of the integrated viral DNA and consequently suppresses viral expression. This strategy was also used in a latently infected CD4+ T-cell model after treatment with a variety of HIV-1 stimulating agents including PMA and TSA. Controlled expression of Cas9 by Tat offers a new strategy for safe implementation of the Cas9 technology for ablation of HIV-1 at a very early stage of HIV-1 replication during the course of the acute phase of infection and the reactivation of silent proviral DNA in latently infected cells. PMID:27528385

  8. Negative Feedback Regulation of HIV-1 by Gene Editing Strategy

    PubMed Central

    Kaminski, Rafal; Chen, Yilan; Salkind, Julian; Bella, Ramona; Young, Won-bin; Ferrante, Pasquale; Karn, Jonathan; Malcolm, Thomas; Hu, Wenhui; Khalili, Kamel

    2016-01-01

    The CRISPR/Cas9 gene editing method is comprised of the guide RNA (gRNA) to target a specific DNA sequence for cleavage and the Cas9 endonuclease for introducing breaks in the double-stranded DNA identified by the gRNA. Co-expression of both a multiplex of HIV-1-specific gRNAs and Cas9 in cells results in the modification and/or excision of the segment of viral DNA, leading to replication-defective virus. In this study, we have personalized the activity of CRISPR/Cas9 by placing the gene encoding Cas9 under the control of a minimal promoter of HIV-1 that is activated by the HIV-1 Tat protein. We demonstrate that functional activation of CRISPR/Cas9 by Tat during the course of viral infection excises the designated segment of the integrated viral DNA and consequently suppresses viral expression. This strategy was also used in a latently infected CD4+ T-cell model after treatment with a variety of HIV-1 stimulating agents including PMA and TSA. Controlled expression of Cas9 by Tat offers a new strategy for safe implementation of the Cas9 technology for ablation of HIV-1 at a very early stage of HIV-1 replication during the course of the acute phase of infection and the reactivation of silent proviral DNA in latently infected cells. PMID:27528385

  9. Myelopathy in a previously asymptomatic HIV-1-infected patient.

    PubMed

    Eyer-Silva, W A; Auto, I; Pinto, J F; Morais-de-Sá, C A

    2001-01-01

    A wide variety of disorders of diverse pathogenic mechanisms can trigger spinal cord dysfunction in HIV-1-infected patients. The most common such condition is HIV-1-associated myelopathy (HM) which characteristically complicates advanced HIV-1 disease in patients with low CD4 cell counts and previous AIDS-defining diagnoses. We describe an unusual presentation of HM in a previously asymptomatic patient with a relatively preserved CD4 cell count (458 cells/mm3) who was even unaware of his serological status. The patient presented with a clinically severe, slowly progressive myelopathy and could not walk unassisted. Significant neurological improvement could be obtained as rapidly as within 4 weeks after the institution of an antiretroviral combination of only two nucleoside analog HIV-1 reverse transcriptase inhibitors (zidovudine and didanosine). An HIV-1 protease inhibitor was also prescribed at that point but could only be added to intensify the regimen 3 months later, when significant neurological improvement had already been recorded. We also review the disorders reported to derange spinal cord function in previously asymptomatic HIV-1-infected patients.

  10. Heterosexual Transmission of Subtype C HIV-1 Selects Consensus-Like Variants without Increased Replicative Capacity or Interferon-α Resistance

    PubMed Central

    Fenton-May, Angharad E.; Dilernia, Dario A.; Kilembe, William; Allen, Susan A.; Borrow, Persephone; Hunter, Eric

    2015-01-01

    Heterosexual transmission of HIV-1 is characterized by a genetic bottleneck that selects a single viral variant, the transmitted/founder (TF), during most transmission events. To assess viral characteristics influencing HIV-1 transmission, we sequenced 167 near full-length viral genomes and generated 40 infectious molecular clones (IMC) including TF variants and multiple non-transmitted (NT) HIV-1 subtype C variants from six linked heterosexual transmission pairs near the time of transmission. Consensus-like genomes sensitive to donor antibodies were selected for during transmission in these six transmission pairs. However, TF variants did not demonstrate increased viral fitness in terms of particle infectivity or viral replicative capacity in activated peripheral blood mononuclear cells (PBMC) and monocyte-derived dendritic cells (MDDC). In addition, resistance of the TF variant to the antiviral effects of interferon-α (IFN-α) was not significantly different from that of non-transmitted variants from the same transmission pair. Thus neither in vitro viral replicative capacity nor IFN-α resistance discriminated the transmission potential of viruses in the quasispecies of these chronically infected individuals. However, our findings support the hypothesis that within-host evolution of HIV-1 in response to adaptive immune responses reduces viral transmission potential. PMID:26378795

  11. Inhibiting early-stage events in HIV-1 replication by small-molecule targeting of the HIV-1 capsid.

    PubMed

    Kortagere, Sandhya; Madani, Navid; Mankowski, Marie K; Schön, Arne; Zentner, Isaac; Swaminathan, Gokul; Princiotto, Amy; Anthony, Kevin; Oza, Apara; Sierra, Luz-Jeannette; Passic, Shendra R; Wang, Xiaozhao; Jones, David M; Stavale, Eric; Krebs, Fred C; Martín-García, Julio; Freire, Ernesto; Ptak, Roger G; Sodroski, Joseph; Cocklin, Simon; Smith, Amos B

    2012-08-01

    The HIV-1 capsid (CA) protein plays essential roles in both early and late stages of virl replication and has emerged as a novel drug target. We report hybrid structure-based virtual screening to identify small molecules with the potential to interact with the N-terminal domain (NTD) of HIV-1 CA and disrupt early, preintegration steps of the HIV-1 replication cycle. The small molecule 4,4'-[dibenzo[b,d]furan-2,8-diylbis(5-phenyl-1H-imidazole-4,2-diyl)]dibenzoic acid (CK026), which had anti-HIV-1 activity in single- and multiple-round infections but failed to inhibit viral replication in peripheral blood mononuclear cells (PBMCs), was identified. Three analogues of CK026 with reduced size and better drug-like properties were synthesized and assessed. Compound I-XW-053 (4-(4,5-diphenyl-1H-imidazol-2-yl)benzoic acid) retained all of the antiviral activity of the parental compound and inhibited the replication of a diverse panel of primary HIV-1 isolates in PBMCs, while displaying no appreciable cytotoxicity. This antiviral activity was specific to HIV-1, as I-XW-053 displayed no effect on the replication of SIV or against a panel of nonretroviruses. Direct interaction of I-XW-053 was quantified with wild-type and mutant CA protein using surface plasmon resonance and isothermal titration calorimetry. Mutation of Ile37 and Arg173, which are required for interaction with compound I-XW-053, crippled the virus at an early, preintegration step. Using quantitative PCR, we demonstrated that treatment with I-XW-053 inhibited HIV-1 reverse transcription in multiple cell types, indirectly pointing to dysfunction in the uncoating process. In summary, we have identified a CA-specific compound that targets and inhibits a novel region in the NTD-NTD interface, affects uncoating, and possesses broad-spectrum anti-HIV-1 activity.

  12. HIV-1 VACCINES. Diversion of HIV-1 vaccine-induced immunity by gp41-microbiota cross-reactive antibodies.

    PubMed

    Williams, Wilton B; Liao, Hua-Xin; Moody, M Anthony; Kepler, Thomas B; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly E; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, M Juliana; Mascola, John R; Koup, Richard A; Corey, Lawrence; Nabel, Gary J; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S; Baden, Lindsey R; Tomaras, Georgia D; Haynes, Barton F

    2015-08-14

    An HIV-1 DNA prime vaccine, with a recombinant adenovirus type 5 (rAd5) boost, failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than to gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells responded to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies were non-neutralizing and frequently polyreactive with host and environmental antigens, including intestinal microbiota (IM). Next-generation sequencing of an immunoglobulin heavy chain variable region repertoire before vaccination revealed an Env-IM cross-reactive Ab that was clonally related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy.

  13. Cell-specific RNA aptamer against human CCR5 specifically targets HIV-1 susceptible cells and inhibits HIV-1 infectivity.

    PubMed

    Zhou, Jiehua; Satheesan, Sangeetha; Li, Haitang; Weinberg, Marc S; Morris, Kevin V; Burnett, John C; Rossi, John J

    2015-03-19

    The C-C chemokine receptor type 5 (CCR5) is a receptor expressed by T cells and macrophages that serves as a coreceptor for macrophage-tropic HIV-1. Loss of CCR5 is associated with resistance to HIV-1. Here, we combine the live-cell-based SELEX with high-throughput sequencing technology to generate CCR5 RNA aptamers capable of specifically targeting HIV-1 susceptible cells (as small interfering RNA [siRNA] delivery agent) and inhibiting HIV-1 infectivity (as antiviral agent) via block of the CCR5 required for HIV-1 to enter cells. One of the best candidates, G-3, efficiently bound and was internalized into human CCR5-expressing cells. The G-3 specifically neutralized R5 virus infection in primary peripheral blood mononuclear cells, and in vivo generated human CD4(+) T cells with a nanomolar inhibitory concentration 50%. G-3 was also capable of transferring functional siRNAs to CCR5-expressing cells. Collectively, the cell-specific, internalizing, CCR5-targeted aptamers and aptamer-siRNA conjugates offer promise for overcoming some of the current challenges of drug resistance in HIV-1 by providing cell-type- or tissue-specific delivery of various therapeutic moieties.

  14. Cell-specific RNA aptamer against human CCR5 specifically targets HIV-1 susceptible and inhibits HIV-1 infectivity

    PubMed Central

    Zhou, Jiehua; Satheesan, Sangeetha; Li, Haitang; Weinberg, Marc S.; Morris, Kevin V.; Burnett, John; Rossi, John

    2015-01-01

    SUMMARY The C-C chemokine receptor type 5 (CCR5) is a receptor expressed by T-cells and macrophages that serves as a co-receptor for macrophage-tropic HIV-1. Loss of CCR5 is associated with resistance to HIV-1. Here we combine the live cell-based SELEX with high throughput sequencing technology to generate CCR5 RNA aptamers capable of specifically targeting HIV-1 susceptible cells (as siRNA delivery agent) and inhibiting HIV-1 infectivity (as antiviral agent) via block of the CCR5 required for HIV-1 to enter cells. One of the best candidates, G-3, efficiently bound and was internalized into human CCR5 expressing cells. The G-3 specifically neutralized R5 virus infection in primary peripheral blood mononuclear cells, and in vivo generated human CD4+ T cells with a nanomolar IC50. G-3 was also capable of transferring functional siRNAs to CCR5 expressing cells. Collectively, the cell-specific, internalizing, CCR5-targeted aptamers and aptamer-siRNA conjugates offer promise for overcoming some of the current challenges of drug resistance in HIV-1 by providing cell-type- or tissue-specific delivery of various therapeutic moieties. PMID:25754473

  15. Profile of the HIV epidemic in Cape Verde: molecular epidemiology and drug resistance mutations among HIV-1 and HIV-2 infected patients from distinct islands of the archipelago.

    PubMed

    de Pina-Araujo, Isabel Inês M; Guimarães, Monick L; Bello, Gonzalo; Vicente, Ana Carolina P; Morgado, Mariza G

    2014-01-01

    HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010-2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1-75) and 47 (IQR = 12-84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be implemented.

  16. Profile of the HIV Epidemic in Cape Verde: Molecular Epidemiology and Drug Resistance Mutations among HIV-1 and HIV-2 Infected Patients from Distinct Islands of the Archipelago

    PubMed Central

    de Pina-Araujo, Isabel Inês M.; Guimarães, Monick L.; Bello, Gonzalo; Vicente, Ana Carolina P.; Morgado, Mariza G.

    2014-01-01

    HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010–2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1–75) and 47 (IQR = 12–84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be

  17. Profile of the HIV epidemic in Cape Verde: molecular epidemiology and drug resistance mutations among HIV-1 and HIV-2 infected patients from distinct islands of the archipelago.

    PubMed

    de Pina-Araujo, Isabel Inês M; Guimarães, Monick L; Bello, Gonzalo; Vicente, Ana Carolina P; Morgado, Mariza G

    2014-01-01

    HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010-2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1-75) and 47 (IQR = 12-84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be implemented

  18. The tyrosine kinase inhibitor genistein blocks HIV-1 infection in primary human macrophages.

    PubMed

    Stantchev, Tzanko S; Markovic, Ingrid; Telford, William G; Clouse, Kathleen A; Broder, Christopher C

    2007-02-01

    Binding of HIV-1 envelope glycoprotein (Env) to its cellular receptors elicits a variety of signaling events, including the activation of select tyrosine kinases. To evaluate the potential role of such signaling, we examined the effects of the tyrosine kinase inhibitor, genistein, on HIV-1 entry and infection of human macrophages using a variety of assays. Without altering cell viability, cell surface expression of CD4 and CCR5 or their abilities to interact with Env, genistein inhibited infection of macrophages by reporter gene-encoding, beta-lactamase containing, or wild type virions, as well as Env-mediated cell-fusion. The observation that genistein blocked virus infection if applied before, during or immediately after the infection period, but not 24h later; coupled with a more pronounced inhibition of infection in the reporter gene assays as compared to both beta-lactamase and p24 particle entry assays, imply that genistein exerts its inhibitory effects on both entry and early post-entry steps. These findings suggest that other exploitable targets, or steps, of the HIV-1 infection process may exist and could serve as additional opportunities for the development of new therapeutics.

  19. HIV-1 evades innate immune recognition through specific cofactor recruitment

    NASA Astrophysics Data System (ADS)

    Rasaiyaah, Jane; Tan, Choon Ping; Fletcher, Adam J.; Price, Amanda J.; Blondeau, Caroline; Hilditch, Laura; Jacques, David A.; Selwood, David L.; James, Leo C.; Noursadeghi, Mahdad; Towers, Greg J.

    2013-11-01

    Human immunodeficiency virus (HIV)-1 is able to replicate in primary human macrophages without stimulating innate immunity despite reverse transcription of genomic RNA into double-stranded DNA, an activity that might be expected to trigger innate pattern recognition receptors. We reasoned that if correctly orchestrated HIV-1 uncoating and nuclear entry is important for evasion of innate sensors then manipulation of specific interactions between HIV-1 capsid and host factors that putatively regulate these processes should trigger pattern recognition receptors and stimulate type 1 interferon (IFN) secretion. Here we show that HIV-1 capsid mutants N74D and P90A, which are impaired for interaction with cofactors cleavage and polyadenylation specificity factor subunit 6 (CPSF6) and cyclophilins (Nup358 and CypA), respectively, cannot replicate in primary human monocyte-derived macrophages because they trigger innate sensors leading to nuclear translocation of NF-κB and IRF3, the production of soluble type 1 IFN and induction of an antiviral state. Depletion of CPSF6 with short hairpin RNA expression allows wild-type virus to trigger innate sensors and IFN production. In each case, suppressed replication is rescued by IFN-receptor blockade, demonstrating a role for IFN in restriction. IFN production is dependent on viral reverse transcription but not integration, indicating that a viral reverse transcription product comprises the HIV-1 pathogen-associated molecular pattern. Finally, we show that we can pharmacologically induce wild-type HIV-1 infection to stimulate IFN secretion and an antiviral state using a non-immunosuppressive cyclosporine analogue. We conclude that HIV-1 has evolved to use CPSF6 and cyclophilins to cloak its replication, allowing evasion of innate immune sensors and induction of a cell-autonomous innate immune response in primary human macrophages.

  20. HIV-1, methamphetamine and astrocytes at neuroinflammatory Crossroads

    PubMed Central

    Borgmann, Kathleen; Ghorpade, Anuja

    2015-01-01

    As a popular psychostimulant, methamphetamine (METH) use leads to long-lasting, strong euphoric effects. While METH abuse is common in the general population, between 10 and 15% of human immunodeficiency virus-1 (HIV-1) patients report having abused METH. METH exacerbates the severity and onset of HIV-1-associated neurocognitive disorders (HAND) through direct and indirect mechanisms. Repetitive METH use impedes adherence to antiretroviral drug regimens, increasing the likelihood of HIV-1 disease progression toward AIDS. METH exposure also directly affects both innate and adaptive immunity, altering lymphocyte numbers and activity, cytokine signaling, phagocytic function and infiltration through the blood brain barrier. Further, METH triggers the dopamine reward pathway and leads to impaired neuronal activity and direct toxicity. Concurrently, METH and HIV-1 alter the neuroimmune balance and induce neuroinflammation, which modulates a wide range of brain functions including neuronal signaling and activity, glial activation, viral infection, oxidative stress, and excitotoxicity. Pathologically, reactive gliosis is a hallmark of both HIV-1- and METH-associated neuroinflammation. Significant commonality exists in the neurotoxic mechanisms for both METH and HAND; however, the pathways dysregulated in astroglia during METH exposure are less clear. Thus, this review highlights alterations in astrocyte intracellular signaling pathways, gene expression and function during METH and HIV-1 comorbidity, with special emphasis on HAND-associated neuroinflammation. Importantly, this review carefully evaluates interventions targeting astrocytes in HAND and METH as potential novel therapeutic approaches. This comprehensive overview indicates, without a doubt, that during HIV-1 infection and METH abuse, a complex dialog between all neural cells is orchestrated through astrocyte regulated neuroinflammation. PMID:26579077

  1. Bioinformatic Analysis of HIV-1 Entry and Pathogenesis

    PubMed Central

    Aiamkitsumrit, Benjamas; Dampier, Will; Antell, Gregory; Rivera, Nina; Martin-Garcia, Julio; Pirrone, Vanessa; Nonnemacher, Michael R.; Wigdahl, Brian

    2015-01-01

    The evolution of human immunodeficiency virus type 1 (HIV-1) with respect to co-receptor utilization has been shown to be relevant to HIV-1 pathogenesis and disease. The CCR5-utilizing (R5) virus has been shown to be important in the very early stages of transmission and highly prevalent during asymptomatic infection and chronic disease. In addition, the R5 virus has been proposed to be involved in neuroinvasion and central nervous system (CNS) disease. In contrast, the CXCR4-utilizing (X4) virus is more prevalent during the course of disease progression and concurrent with the loss of CD4+ T cells. The dual-tropic virus is able to utilize both co-receptors (CXCR4 and CCR5) and has been thought to represent an intermediate transitional virus that possesses properties of both X4 and R5 viruses that can be encountered at many stages of disease. The use of computational tools and bioinformatic approaches in the prediction of HIV-1 co-receptor usage has been growing in importance with respect to understanding HIV-1 pathogenesis and disease, developing diagnostic tools, and improving the efficacy of therapeutic strategies focused on blocking viral entry. Current strategies have enhanced the sensitivity, specificity, and reproducibility relative to the prediction of co-receptor use; however, these technologies need to be improved with respect to their efficient and accurate use across the HIV-1 subtypes. The most effective approach may center on the combined use of different algorithms involving sequences within and outside of the env-V3 loop. This review focuses on the HIV-1 entry process and on co-receptor utilization, including bioinformatic tools utilized in the prediction of co-receptor usage. It also provides novel preliminary analyses for enabling identification of linkages between amino acids in V3 with other components of the HIV-1 genome and demonstrates that these linkages are different between X4 and R5 viruses. PMID:24862329

  2. Phylodynamics of the HIV-1 epidemic in Cuba.

    PubMed

    Delatorre, Edson; Bello, Gonzalo

    2013-01-01

    Previous studies have shown that the HIV-1 epidemic in Cuba displayed a complex molecular epidemiologic profile with circulation of several subtypes and circulating recombinant forms (CRF); but the evolutionary and population history of those viral variants remains unknown. HIV-1 pol sequences of the most prevalent Cuban lineages (subtypes B, C and G, CRF18_cpx, CRF19_cpx, and CRFs20/23/24_BG) isolated between 1999 and 2011 were analyzed. Maximum-likelihood analyses revealed multiple introductions of subtype B (n≥66), subtype C (n≥10), subtype G (n≥8) and CRF18_cpx (n≥2) viruses in Cuba. The bulk of HIV-1 infections in this country, however, was caused by dissemination of a few founder strains probably introduced from North America/Europe (clades B(CU-I) and B(CU-II)), east Africa (clade C(CU-I)) and central Africa (clades G(CU), CRF18(CU) and CRF19(CU)), or locally generated (clades CRFs20/23/24_BG). Bayesian-coalescent analyses show that the major HIV-1 founder strains were introduced into Cuba during 1985-1995; whereas the CRFs_BG strains emerged in the second half of the 1990s. Most HIV-1 Cuban clades appear to have experienced an initial period of fast exponential spread during the 1990s and early 2000s, followed by a more recent decline in growth rate. The median initial growth rate of HIV-1 Cuban clades ranged from 0.4 year⁻¹ to 1.6 year⁻¹. Thus, the HIV-1 epidemic in Cuba has been a result of the successful introduction of a few viral strains that began to circulate at a rather late time of the AIDS pandemic, but then were rapidly disseminated through local transmission networks.

  3. Cultivated Vaginal Microbiomes Alter HIV-1 Infection and Antiretroviral Efficacy in Colonized Epithelial Multilayer Cultures

    PubMed Central

    Pyles, Richard B.; Vincent, Kathleen L.; Baum, Marc M.; Elsom, Barry; Miller, Aaron L.; Maxwell, Carrie; Eaves-Pyles, Tonyia D.; Li, Guangyu; Popov, Vsevolod L.; Nusbaum, Rebecca J.; Ferguson, Monique R.

    2014-01-01

    There is a pressing need for modeling of the symbiotic and at times dysbiotic relationship established between bacterial microbiomes and human mucosal surfaces. In particular clinical studies have indicated that the complex vaginal microbiome (VMB) contributes to the protection against sexually-transmitted pathogens including the life-threatening human immunodeficiency virus (HIV-1). The human microbiome project has substantially increased our understanding of the complex bacterial communities in the vagina however, as is the case for most microbiomes, very few of the community member species have been successfully cultivated in the laboratory limiting the types of studies that can be completed. A genetically controlled ex vivo model system is critically needed to study the complex interactions and associated molecular dialog. We present the first vaginal mucosal culture model that supports colonization by both healthy and dysbiotic VMB from vaginal swabs collected from routine gynecological patients. The immortalized vaginal epithelial cells used in the model and VMB cryopreservation methods provide the opportunity to reproducibly create replicates for lab-based evaluations of this important mucosal/bacterial community interface. The culture system also contains HIV-1 susceptible cells allowing us to study the impact of representative microbiomes on replication. Our results show that our culture system supports stable and reproducible colonization by VMB representing distinct community state types and that the selected representatives have significantly different effects on the replication of HIV-1. Further, we show the utility of the system to predict unwanted alterations in efficacy or bacterial community profiles following topical application of a front line antiretroviral. PMID:24676219

  4. Assessing transmissibility of HIV-1 drug resistance mutations from treated and from drug-naive individuals

    PubMed Central

    Winand, Raf; Theys, Kristof; Eusébio, Mónica; Aerts, Jan; Camacho, Ricardo J.; Gomes, Perpetua; Suchard, Marc A.; Vandamme, Anne-Mieke; Abecasis, Ana B.

    2015-01-01

    Objectives: Surveillance drug resistance mutations (SDRMs) in drug-naive patients are typically used to survey HIV-1-transmitted drug resistance (TDR). We test here how SDRMs in patients failing treatment, the original source of TDR, contribute to assessing TDR, transmissibility and transmission source of SDRMs. Design: This is a retrospective observational study analyzing a Portuguese cohort of HIV-1-infected patients. Methods: The prevalence of SDRMs to protease inhibitors, nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) in drug-naive and treatment-failing patients was measured for 3554 HIV-1 subtype B patients. Transmission ratio (prevalence in drug-naive/prevalence in treatment-failing patients), average viral load and robust linear regression with outlier detection (prevalence in drug-naive versus in treatment-failing patients) were analyzed and used to interpret transmissibility. Results: Prevalence of SDRMs in drug-naive and treatment-failing patients were linearly correlated, but some SDRMs were classified as outliers – above (PRO: D30N, N88D/S, L90 M, RT: G190A/S/E) or below (RT: M184I/V) expectations. The normalized regression slope was 0.073 for protease inhibitors, 0.084 for NRTIs and 0.116 for NNRTIs. Differences between SDRMs transmission ratios were not associated with differences in viral loads. Conclusion: The significant linear correlation between prevalence of SDRMs in drug-naive and in treatment-failing patients indicates that the prevalence in treatment-failing patients can be useful to predict levels of TDR. The slope is a cohort-dependent estimate of rate of TDR per drug class and outlier detection reveals comparative persistence of SDRMs. Outlier SDRMs with higher transmissibility are more persistent and more likely to have been acquired from drug-naive patients. Those with lower transmissibility have faster reversion dynamics after transmission and are associated with

  5. HIV-1, human interaction database: current status and new features.

    PubMed

    Ako-Adjei, Danso; Fu, William; Wallin, Craig; Katz, Kenneth S; Song, Guangfeng; Darji, Dakshesh; Brister, J Rodney; Ptak, Roger G; Pruitt, Kim D

    2015-01-01

    The 'Human Immunodeficiency Virus Type 1 (HIV-1), Human Interaction Database', available through the National Library of Medicine at http://www.ncbi.nlm.nih.gov/genome/viruses/retroviruses/hiv-1/interactions, serves the scientific community exploring the discovery of novel HIV vaccine candidates and therapeutic targets. Each HIV-1 human protein interaction can be retrieved without restriction by web-based downloads and ftp protocols and includes: Reference Sequence (RefSeq) protein accession numbers, National Center for Biotechnology Information Gene identification numbers, brief descriptions of the interactions, searchable keywords for interactions and PubMed identification numbers (PMIDs) of journal articles describing the interactions. In addition to specific HIV-1 protein-human protein interactions, included are interaction effects upon HIV-1 replication resulting when individual human gene expression is blocked using siRNA. A total of 3142 human genes are described participating in 12,786 protein-protein interactions, along with 1316 replication interactions described for each of 1250 human genes identified using small interfering RNA (siRNA). Together the data identifies 4006 human genes involved in 14,102 interactions. With the inclusion of siRNA interactions we introduce a redesigned web interface to enhance viewing, filtering and downloading of the combined data set.

  6. HIV-1 functional cure: will the dream come true?

    PubMed

    Liu, Chao; Ma, Xiancai; Liu, Bingfeng; Chen, Cancan; Zhang, Hui

    2015-11-20

    The reservoir of human immunodeficiency virus type 1 (HIV-1), a long-lived pool of latently infected cells harboring replication-competent viruses, is the major obstacle to curing acquired immune deficiency syndrome (AIDS). Although the combination antiretroviral therapy (cART) can successfully suppress HIV-1 viremia and significantly delay the progression of the disease, it cannot eliminate the viral reservoir and the patient must continue to take anti-viral medicines for life. Currently, the appearance of the 'Berlin patient', the 'Boston patients', and the 'Mississippi baby' have inspired many therapeutic strategies for HIV-1 aimed at curing efforts. However, the specific eradication of viral latency and the recovery and optimization of the HIV-1-specific immune surveillance are major challenges to achieving such a cure. Here, we summarize recent studies addressing the mechanisms underlying the viral latency and define two categories of viral reservoir: 'shallow' and 'deep'. We also present the current strategies and recent advances in the development of a functional cure for HIV-1, focusing on full/partial replacement of the immune system, 'shock and kill', and 'permanent silencing' approaches.

  7. The HIV-1 transgenic rat model of neuroHIV

    PubMed Central

    Vigorito, Michael; Connaghan, Kaitlyn P.; Chang, Sulie L.

    2016-01-01

    Despite the ability of current combination anti-retroviral therapy (cART) to limit the progression of HIV-1 to AIDS, HIV-positive individuals continue to experience neuroHIV in the form of HIV-associated neurological disorders (HAND), which can range from subtle to substantial neurocognitive impairment. NeuroHIV may also influence substance use, abuse, and dependence in HIV-positive individuals. Because of the nature of the virus, variables such as mental health co-morbidities make it difficult to study the interaction between HIV and substance abuse in human populations. Several rodent models have been developed in an attempt to study the transmission and pathogenesis of the HIV-1 virus. The HIV-1 transgenic (HIV-1Tg) rat is a reliable model of neuroHIV because it mimics the condition of HIV-infected patients on cART. Research using this model supports the hypothesis that the presence of HIV-1 viral proteins in the central nervous system increases the sensitivity and susceptibility of HIV-positive individuals to substance abuse. PMID:25733103

  8. Neutralizing antibodies decrease the envelope fluidity of HIV-1

    SciTech Connect

    Harada, Shinji Monde, Kazuaki; Tanaka, Yuetsu; Kimura, Tetsuya; Maeda, Yosuke; Yusa, Keisuke

    2008-01-05

    For successful penetration of HIV-1, the formation of a fusion pore may be required in order to accumulate critical numbers of fusion-activated gp41 with the help of fluidization of the plasma membrane and viral envelope. An increase in temperature to 40 {sup o}C after viral adsorption at 25 {sup o}C enhanced the infectivity by 1.4-fold. The enhanced infectivity was inhibited by an anti-CXCR4 peptide, T140, and anti-V3 monoclonal antibodies (0.5{beta} and 694/98-D) by post-attachment neutralization, but not by non-neutralizing antibodies (670-30D and 246-D) specific for the C5 of gp120 and cluster I of gp41, respectively. Anti-HLA-II and an anti-HTLV-I gp46 antibody, LAT27, neutralized the molecule-carrying HIV-1{sub C-2(MT-2)}. The anti-V3 antibodies suppressed the fluidity of the HIV-1{sub C-2} envelope, whereas the non-neutralizing antibodies did not. The anti-HLA-II antibody decreased the envelope fluidity of HIV-1{sub C-2(MT-2)}, but not that of HIV-1{sub C-2}. Therefore, fluidity suppression by these antibodies represents an important neutralization mechanism, in addition to inhibition of viral attachment.

  9. Characterization of HIV-1 Resistance to Tenofovir Alafenamide In Vitro.

    PubMed

    Margot, Nicolas A; Johnson, Audun; Miller, Michael D; Callebaut, Christian

    2015-10-01

    Tenofovir alafenamide (TAF) is an investigational prodrug of the HIV-1 nucleotide reverse transcriptase (RT) inhibitor (NtRTI) tenofovir (TFV), with improved potency and drug delivery properties over the current prodrug, tenofovir disoproxil fumarate (TDF). TAF is currently in phase 3 clinical studies for the treatment of HIV-1 infection, in combination with other antiretroviral agents. Phase 1 and 2 studies have shown that TAF was associated with increased peripheral blood mononuclear cell (PBMC) drug loading and increased suppression of HIV-1 replication compared to treatment with TDF. In this study, selection of in vitro resistance to both TAF and the parent compound, TFV, led to the emergence of HIV-1 with the K65R amino acid substitution in RT with 6.5-fold-reduced susceptibility to TAF. Although TAF is more potent than TFV in vitro, the antiviral susceptibilities to TAF and TFV of a large panel of nucleoside/nucleotide RT inhibitor (NRTI)-resistant mutants were highly correlated (R(2) = 0.97), indicating that the two compounds have virtually the same resistance profile when assessed as fold change from the wild type. TAF showed full antiviral activity in PBMCs against primary HIV-1 isolates with protease inhibitor, nonnucleoside RT inhibitor (NNRTI), or integrase strand transfer inhibitor resistance but reduced activity against isolates with extensive NRTI resistance amino acid substitutions. However, the increased cell loading of TFV with TAF versus TDF observed in vivo suggests that TAF may retain activity against TDF-resistant mutant viruses. PMID:26149983

  10. APOBEC4 Enhances the Replication of HIV-1

    PubMed Central

    Hofmann, Henning; Hanschmann, Kay-Martin; Mühlebach, Michael D.; Schumann, Gerald G.; König, Renate; Cichutek, Klaus; Häussinger, Dieter; Münk, Carsten

    2016-01-01

    APOBEC4 (A4) is a member of the AID/APOBEC family of cytidine deaminases. In this study we found a high mRNA expression of A4 in human testis. In contrast, there were only low levels of A4 mRNA detectable in 293T, HeLa, Jurkat or A3.01 cells. Ectopic expression of A4 in HeLa cells resulted in mostly cytoplasmic localization of the protein. To test whether A4 has antiviral activity similar to that of proteins of the APOBEC3 (A3) subfamily, A4 was co-expressed in 293T cells with wild type HIV-1 and HIV-1 luciferase reporter viruses. We found that A4 did not inhibit the replication of HIV-1 but instead enhanced the production of HIV-1 in a dose-dependent manner and seemed to act on the viral LTR. A4 did not show detectable cytidine deamination activity in vitro and weakly interacted with single-stranded DNA. The presence of A4 in virus producer cells enhanced HIV-1 replication by transiently transfected A4 or stably expressed A4 in HIV-susceptible cells. APOBEC4 was capable of similarly enhancing transcription from a broad spectrum of promoters, regardless of whether they were viral or mammalian. We hypothesize that A4 may have a natural role in modulating host promoters or endogenous LTR promoters. PMID:27249646

  11. Diversity of in-vivo assembled HIV-1 capsids

    NASA Astrophysics Data System (ADS)

    Lee, Se Il; Nguyen, Toan

    2008-03-01

    Understanding the capsid assembly process of Human Immunodeficiency Virus (HIV), the causative agent of Acute Immuno Deficiency Syndrom (AIDS), is very important because of recent intense interest in capsid-oriented viral therapy. The unique conical shapes of mature HIV-1 capsid have drawn significant interests in the biological community and started to attract attention from the physics community. Previous studies showed that in a free assembly process, the HIV-1 conical shape is not thermodynamically stable. However, if the volume of the capsid is constrained during assembly and the capsid protein shell has high spontaneous curvature, the conical shape is stable. In this work, we focus on in-vivo HIV-1 capsid assembly. For this case, the viral envelope membrane present during assembly imposes constraint on the length of the capsid. We use an elastic continuum shell theory to approximate the energies of various HIV-1 capsid shapes (spherical, cylindrical and conical). We show that for certain range of viral membrane diameter, the conical and cylindrical shapes are both thermodynamically stable. This result is supported by experimental observation that in-vivo assembled HIV-1 capsids are very heterogeneous in shapes and sizes. Numerical calculation is also performed to improve theoretical approximation.

  12. Inhibitors of HIV-1 replication that inhibit HIV integrase.

    PubMed Central

    Robinson, W E; Reinecke, M G; Abdel-Malek, S; Jia, Q; Chow, S A

    1996-01-01

    HIV-1 replication depends on the viral enzyme integrase that mediates integration of a DNA copy of the virus into the host cell genome. This enzyme represents a novel target to which antiviral agents might be directed. Three compounds, 3,5-dicaffeoylquinic acid, 1-methoxyoxalyl-3,5-dicaffeoylquinic acid, and L-chicoric acid, inhibit HIV-1 integrase in biochemical assays at concentrations ranging from 0.06-0.66 microgram/ml; furthermore, these compounds inhibit HIV-1 replication in tissue culture at 1-4 microgram/ml. The toxic concentrations of these compounds are fully 100-fold greater than their antiviral concentrations. These compounds represent a potentially important new class of antiviral agents that may contribute to our understanding of the molecular mechanisms of viral integration. Thus, the dicaffeoylquinic acids are promising leads to new anti-HIV therapeutics and offer a significant advance in the search for new HIV enzyme targets as they are both specific for HIV-1 integrase and active against HIV-1 in tissue culture. Images Fig. 3 PMID:8692814

  13. HIV-1 subtype B: Traces of a pandemic.

    PubMed

    Junqueira, Dennis Maletich; Almeida, Sabrina Esteves de Matos

    2016-08-01

    Human migration is a major process that shaped the origin and dissemination of HIV. Within HIV-1, subtype B (HIV-1B) is the most disseminated variant and it is assumed to be the causative agent in approximately 11% of all cases of HIV worldwide. Phylogenetic studies have revealed that HIV-1B emerged in Kinshasa (Africa) and was introduced into the Caribbean region via Haiti in or around 1966 by human migration. After localized dispersion, the virus was brought to the United States of America via homosexual/bisexual contact around 1969. Inside USA, the incidence of HIV-1B infection increased exponentially and it became established in the population, affecting not only homosexual individuals but also heterosexual individuals and injecting drug users. Soon after, the virus was disseminated and became established in other regions, including Europe, Asia, Latin America, and Australia. Recent studies suggest that, in addition to this pandemic clade, several lineages have emerged from Haiti and reached other Caribbean and Latin American countries via short-distance dissemination. Different subtype B genetic variants have also been detected in these epidemics. Four genetic variants have been described to date: subtype B', which mainly circulates in Thailand and other Asian countries; a specific variant mainly found in Trinidad and Tobago; the GPGS variant, which is primarily detected in Korea; and the GWGR variant, which is mainly detected in Brazil. This paper reviews the evolution of HIV-1B and its impact on the human population.

  14. HIV-1 functional cure: will the dream come true?

    PubMed

    Liu, Chao; Ma, Xiancai; Liu, Bingfeng; Chen, Cancan; Zhang, Hui

    2015-01-01

    The reservoir of human immunodeficiency virus type 1 (HIV-1), a long-lived pool of latently infected cells harboring replication-competent viruses, is the major obstacle to curing acquired immune deficiency syndrome (AIDS). Although the combination antiretroviral therapy (cART) can successfully suppress HIV-1 viremia and significantly delay the progression of the disease, it cannot eliminate the viral reservoir and the patient must continue to take anti-viral medicines for life. Currently, the appearance of the 'Berlin patient', the 'Boston patients', and the 'Mississippi baby' have inspired many therapeutic strategies for HIV-1 aimed at curing efforts. However, the specific eradication of viral latency and the recovery and optimization of the HIV-1-specific immune surveillance are major challenges to achieving such a cure. Here, we summarize recent studies addressing the mechanisms underlying the viral latency and define two categories of viral reservoir: 'shallow' and 'deep'. We also present the current strategies and recent advances in the development of a functional cure for HIV-1, focusing on full/partial replacement of the immune system, 'shock and kill', and 'permanent silencing' approaches. PMID:26588898

  15. HIV-1 subtype B: Traces of a pandemic.

    PubMed

    Junqueira, Dennis Maletich; Almeida, Sabrina Esteves de Matos

    2016-08-01

    Human migration is a major process that shaped the origin and dissemination of HIV. Within HIV-1, subtype B (HIV-1B) is the most disseminated variant and it is assumed to be the causative agent in approximately 11% of all cases of HIV worldwide. Phylogenetic studies have revealed that HIV-1B emerged in Kinshasa (Africa) and was introduced into the Caribbean region via Haiti in or around 1966 by human migration. After localized dispersion, the virus was brought to the United States of America via homosexual/bisexual contact around 1969. Inside USA, the incidence of HIV-1B infection increased exponentially and it became established in the population, affecting not only homosexual individuals but also heterosexual individuals and injecting drug users. Soon after, the virus was disseminated and became established in other regions, including Europe, Asia, Latin America, and Australia. Recent studies suggest that, in addition to this pandemic clade, several lineages have emerged from Haiti and reached other Caribbean and Latin American countries via short-distance dissemination. Different subtype B genetic variants have also been detected in these epidemics. Four genetic variants have been described to date: subtype B', which mainly circulates in Thailand and other Asian countries; a specific variant mainly found in Trinidad and Tobago; the GPGS variant, which is primarily detected in Korea; and the GWGR variant, which is mainly detected in Brazil. This paper reviews the evolution of HIV-1B and its impact on the human population. PMID:27228177

  16. HIV-1, human interaction database: current status and new features

    PubMed Central

    Ako-Adjei, Danso; Fu, William; Wallin, Craig; Katz, Kenneth S.; Song, Guangfeng; Darji, Dakshesh; Brister, J. Rodney; Ptak, Roger G.; Pruitt, Kim D.

    2015-01-01

    The ‘Human Immunodeficiency Virus Type 1 (HIV-1), Human Interaction Database’, available through the National Library of Medicine at http://www.ncbi.nlm.nih.gov/genome/viruses/retroviruses/hiv-1/interactions, serves the scientific community exploring the discovery of novel HIV vaccine candidates and therapeutic targets. Each HIV-1 human protein interaction can be retrieved without restriction by web-based downloads and ftp protocols and includes: Reference Sequence (RefSeq) protein accession numbers, National Center for Biotechnology Information Gene identification numbers, brief descriptions of the interactions, searchable keywords for interactions and PubMed identification numbers (PMIDs) of journal articles describing the interactions. In addition to specific HIV-1 protein–human protein interactions, included are interaction effects upon HIV-1 replication resulting when individual human gene expression is blocked using siRNA. A total of 3142 human genes are described participating in 12 786 protein–protein interactions, along with 1316 replication interactions described for each of 1250 human genes identified using small interfering RNA (siRNA). Together the data identifies 4006 human genes involved in 14 102 interactions. With the inclusion of siRNA interactions we introduce a redesigned web interface to enhance viewing, filtering and downloading of the combined data set. PMID:25378338

  17. Ketone bodies protection against HIV-1 Tat-induced neurotoxicity

    PubMed Central

    Hui, Liang; Chen, Xuesong; Bhatt, Dhaval; Geiger, Nicholas H.; Rosenberger, Thad A.; Haughey, Norman J.; Masino, Susan A.; Geiger, Jonathan D.

    2012-01-01

    HIV-1 associated neurocognitive disorder (HAND) is a syndrome that ranges clinically from subtle neuropsychological impairments to profoundly disabling HIV-associated dementia. Not only is the pathogenesis of HAND unclear, but also effective treatments are unavailable. The HIV-1 transactivator of transcription protein (HIV-1 Tat) is strongly implicated in the pathogenesis of HAND, in part, because of its well-characterized ability to directly excite neurons and cause neurotoxicity. Consistent with previous findings from others, we demonstrate here that HIV-1 Tat induced neurotoxicity, increased intracellular calcium, and disrupted a variety of mitochondria functions, such as reducing mitochondrial membrane potential, increasing levels of reactive oxygen species, and decreasing bioenergetic efficiency. Of therapeutic importance, we show that treatment of cultured neurons with ketone bodies normalized HIV-1 Tat induced changes in levels of intracellular calcium, mitochondrial function, and neuronal cell death. Ketone bodies are normally produced in the body and serve as alternative energy substrates in tissues including brain and can cross the blood-brain barrier. Ketogenic strategies have been used clinically for treatment of neurological disorders and our current results suggest that similar strategies may also provide clinical benefits in the treatment of HAND. PMID:22524563

  18. Antimalarial activity of HIV-1 protease inhibitor in chromone series.

    PubMed

    Lerdsirisuk, Pradith; Maicheen, Chirattikan; Ungwitayatorn, Jiraporn

    2014-12-01

    Increasing parasite resistance to nearly all available antimalarial drugs becomes a serious problem to human health and necessitates the need to continue the search for new effective drugs. Recent studies have shown that clinically utilized HIV-1 protease (HIV-1 PR) inhibitors can inhibit the in vitro and in vivo growth of Plasmodium falciparum. In this study, a series of chromone derivatives possessing HIV-1 PR inhibitory activity has been tested for antimalarial activity against P. falciparum (K1 multi-drug resistant strain). Chromone 15, the potent HIV-1 PR inhibitor (IC50=0.65μM), was found to be the most potent antimalarial compound with IC50=0.95μM while primaquine and tafenoquine showed IC50=2.41 and 1.95μM, respectively. Molecular docking study of chromone compounds against plasmepsin II, an aspartic protease enzyme important in hemoglobin degradation, revealed that chromone 15 exhibited the higher binding affinity (binding energy=-13.24kcal/mol) than the known PM II inhibitors. Thus, HIV-1 PR inhibitor in chromone series has the potential to be a new class of antimalarial agent. PMID:25462990

  19. [Advances in the Immunogenic Design of HIV-1 Vaccine].

    PubMed

    Zhang, Xiaohong; Wang, Tao; Yu, Xiaofang

    2016-01-01

    A safe and effective vaccine against the human immunodeficiency virus type 1 (HIV-1) is expected to have a considerable impact on elimination of acquired immune deficiency syndrome. Despite decades of effort, an effective vaccine against HIV-1 remains elusive. In recent years, the Thai HIV Vaccine Efficacy Trial (known as RV144) showed a reduction in HIV-1 acquisition by 31%, but this agent could not delay disease progression in vaccinated individuals. Clinical analyses of experimental data and experiments in vitro have revealed two main types of immunogen design: induction of broad-spectrum neutralizing antibody (bNAb) and cytotoxic T lymphocyte (CTL) responses. bNAb can prevent or reduce acquisition of infection, and its main immunogens are virus-like particles, natural envelope trimers and stable bNAb epitopes. An effective CTL response can slow-down viral infection, and its main immunogens are "mosaic" vaccines, "conserved immunogens", and the "fitness landscape" of HIV-1 proteins. This review summarizes the strategies as well as progress in the design and testing of HIV-1 immunogens to elicit bNAb and CTL responses. PMID:27295889

  20. The triple threat of HIV-1 protease inhibitors.

    PubMed

    Potempa, Marc; Lee, Sook-Kyung; Wolfenden, Richard; Swanstrom, Ronald

    2015-01-01

    Newly released human immunodeficiency virus type 1 (HIV-1) particles obligatorily undergo a maturation process to become infectious. The HIV-1 protease (PR) initiates this step, catalyzing the cleavage of the Gag and Gag-Pro-Pol structural polyproteins. Proper organization of the mature virus core requires that cleavage of these polyprotein substrates proceeds in a highly regulated, specific series of events. The vital role the HIV-1 PR plays in the viral life cycle has made it an extremely attractive target for inhibition and has accordingly fostered the development of a number of highly potent substrate-analog inhibitors. Though the PR inhibitors (PIs) inhibit only the HIV-1 PR, their effects manifest at multiple different stages in the life cycle due to the critical importance of the PR in preparing the virus for these subsequent events. Effectively, PIs masquerade as entry inhibitors, reverse transcription inhibitors, and potentially even inhibitors of post-reverse transcription steps. In this chapter, we review the triple threat of PIs: the intermolecular cooperativity in the form of a cooperative dose-response for inhibition in which the apparent potency increases with increasing inhibition; the pleiotropic effects of HIV-1 PR inhibition on entry, reverse transcription, and post-reverse transcription steps; and their potency as transition state analogs that have the potential for further improvement that could lead to an inability of the virus to evolve resistance in the context of single drug therapy. PMID:25778681

  1. Antiretroviral Therapy and Central Nervous System HIV-1 Infection

    PubMed Central

    Price, Richard W.; Spudich, Serena

    2008-01-01

    Central nervous system (CNS) HIV-1 infection begins during primary viremia and continues throughout the course of untreated systemic infection. While frequently accompanied by local inflammatory reactions detectable in cerebrospinal fluid (CSF), CNS HIV-1 infection is not usually clinically apparent. In a minority of patients, CNS HIV-1 infection evolves late in the course of systemic infection into encephalitis, which compromises brain function and presents clinically as AIDS dementia complex (ADC). Combination highly active antiretroviral therapy (HAART) has had a major impact on all aspects of HIV-1 CNS infection and disease. In those with asymptomatic infection, HAART usually effectively suppresses CSF HIV-1 and markedly reduces the incidence of symptomatic ADC. In those presenting with ADC, HAART characteristically prevents neurological progression and leads to variable, and at times substantial, recovery. Treatment has similarly reduced CNS opportunistic infections. With better control of these severe disorders, attention has turned to the possible consequences of chronic silent infection, and the issue of whether indolent, low-grade brain injury might require earlier treatment intervention. PMID:18447615

  2. Combinatorial Latency Reactivation for HIV-1 Subtypes and Variants▿ †

    PubMed Central

    Burnett, John C.; Lim, Kwang-il; Calafi, Arash; Rossi, John J.; Schaffer, David V.; Arkin, Adam P.

    2010-01-01

    The eradication of HIV-1 will likely require novel clinical approaches to purge the reservoir of latently infected cells from a patient. We hypothesize that this therapy should target a wide range of latent integration sites, act effectively against viral variants that have acquired mutations in their promoter regions, and function across multiple HIV-1 subtypes. By using primary CD4+ and Jurkat cell-based in vitro HIV-1 latency models, we observe that single-agent latency reactivation therapy is ineffective against most HIV-1 subtypes. However, we demonstrate that the combination of two clinically promising drugs—namely, prostratin and suberoylanilide hydroxamic acid (SAHA)—overcomes the limitations of single-agent approaches and can act synergistically for many HIV-1 subtypes, including A, B, C, D, and F. Finally, by identifying the proviral integration position of latent Jurkat cell clones, we demonstrate that this drug combination does not significantly enhance the expression of endogenous genes nearest to the proviral integration site, indicating that its effects may be selective. PMID:20357084

  3. Preexisting compensatory amino acids compromise fitness costs of a HIV-1 T cell escape mutation

    SciTech Connect

    Liu, Donglai; Zuo, Tao; Hora, Bhavna; Song, Hongshuo; Kong, Wei; Yu, Xianghui; Goonetilleke, Nilu; Bhattacharya, Tanmoy; Perelson, Alan S.; Haynes, Barton F.; McMichael, Andrew J.; Gao, Feng

    2014-01-01

    Background: Fitness costs and slower disease progression are associated with a cytolytic T lymphocyte (CTL) escape mutation T242N in Gag in HIV-1-infected individuals carrying HLA-B*57/5801 alleles. However, the impact of different context in diverse HIV-1 strains on the fitness costs due to the T242N mutation has not been well characterized. To better understand the extent of fitness costs of the T242N mutation and the repair of fitness loss through compensatory amino acids, we investigated its fitness impact in different transmitted/founder (T/F) viruses. Results: The T242N mutation resulted in various levels of fitness loss in four different T/F viruses. However, the fitness costs were significantly compromised by preexisting compensatory amino acids in (Isoleucine at position 247) or outside (glutamine at position 219) the CTL epitope. Moreover, the transmitted T242N escape mutant in subject CH131 was as fit as the revertant N242T mutant and the elimination of the compensatory amino acid I247 in the T/F viral genome resulted in significant fitness cost, suggesting the fitness loss caused by the T242N mutation had been fully repaired in the donor at transmission. Analysis of the global circulating HIV-1 sequences in the Los Alamos HIV Sequence Database showed a high prevalence of compensatory amino acids for the T242N mutation and other T cell escape mutations. Conclusions: Our results show that the preexisting compensatory amino acids in the majority of circulating HIV-1 strains could significantly compromise the fitness loss due to CTL escape mutations and thus increase challenges for T cell based vaccines.

  4. Preexisting compensatory amino acids compromise fitness costs of a HIV-1 T cell escape mutation

    DOE PAGES

    Liu, Donglai; Zuo, Tao; Hora, Bhavna; Song, Hongshuo; Kong, Wei; Yu, Xianghui; Goonetilleke, Nilu; Bhattacharya, Tanmoy; Perelson, Alan S.; Haynes, Barton F.; et al

    2014-01-01

    Background: Fitness costs and slower disease progression are associated with a cytolytic T lymphocyte (CTL) escape mutation T242N in Gag in HIV-1-infected individuals carrying HLA-B*57/5801 alleles. However, the impact of different context in diverse HIV-1 strains on the fitness costs due to the T242N mutation has not been well characterized. To better understand the extent of fitness costs of the T242N mutation and the repair of fitness loss through compensatory amino acids, we investigated its fitness impact in different transmitted/founder (T/F) viruses. Results: The T242N mutation resulted in various levels of fitness loss in four different T/F viruses. However, themore » fitness costs were significantly compromised by preexisting compensatory amino acids in (Isoleucine at position 247) or outside (glutamine at position 219) the CTL epitope. Moreover, the transmitted T242N escape mutant in subject CH131 was as fit as the revertant N242T mutant and the elimination of the compensatory amino acid I247 in the T/F viral genome resulted in significant fitness cost, suggesting the fitness loss caused by the T242N mutation had been fully repaired in the donor at transmission. Analysis of the global circulating HIV-1 sequences in the Los Alamos HIV Sequence Database showed a high prevalence of compensatory amino acids for the T242N mutation and other T cell escape mutations. Conclusions: Our results show that the preexisting compensatory amino acids in the majority of circulating HIV-1 strains could significantly compromise the fitness loss due to CTL escape mutations and thus increase challenges for T cell based vaccines.« less

  5. Development of a Multiplex Real-Time PCR Assay for the Detection of Treponema pallidum, HCV, HIV-1, and HBV.

    PubMed

    Zhou, Li; Gong, Rui; Lu, Xuan; Zhang, Yi; Tang, Jingfeng

    2015-01-01

    Treponema pallidum, hepatitis C virus (HCV), human immunodeficiency virus (HIV)-1, and hepatitis B virus (HBV) are major causes of sexually transmitted diseases passed through blood contact. The development of a sensitive and efficient method for detection is critical for early diagnosis and for large-scale screening of blood specimens in China. This study aims to establish an assay to detect these pathogens in clinical serum specimens. We established a TaqMan-locked nucleic acid (LNA) real-time polymerase chain reaction (PCR) assay for rapid, sensitive, specific, quantitative, and simultaneous detection and identification. The copy numbers of standards of these 4 pathogens were quantified. Standard curves were generated by determining the mean cycle threshold values versus 10-fold serial dilutions of standards over a range of 10(6) to 10(1) copies/μL, with the lowest detection limit of the assay being 10(1) copies/μL. The assay was applied to 328 clinical specimens and compared with enzyme-linked immunosorbent assay (ELISA) and commercial nucleic acid testing (NAT) methods. The assay identified 39 T. pallidum-, 96 HCV-, 13 HIV-1-, 123 HBV-, 5 HBV/HCV-, 1 T. pallidum/HBV-, 1 HIV-1/HCV-, and 1 HIV-1/T. pallidum-positive specimens. The high sensitivity of the assay confers strong potential for its use as a highly reliable, cost-effective, and useful molecular diagnostic tool for large-scale screening of clinical specimens. This assay will assist in the study of the pathogenesis and epidemiology of sexually transmitted blood diseases. PMID:25866106

  6. A small molecule HIV-1 inhibitor that targets the HIV-1 envelope and inhibits CD4 receptor binding

    PubMed Central

    Lin, Pin-Fang; Blair, Wade; Wang, Tao; Spicer, Timothy; Guo, Qi; Zhou, Nannan; Gong, Yi-Fei; Wang, H.-G. Heidi; Rose, Ronald; Yamanaka, Gregory; Robinson, Brett; Li, Chang-Ben; Fridell, Robert; Deminie, Carol; Demers, Gwendeline; Yang, Zheng; Zadjura, Lisa; Meanwell, Nicholas; Colonno, Richard

    2003-01-01

    BMS-378806 is a recently discovered small molecule HIV-1 inhibitor that blocks viral entrance to cells. The compound exhibits potent inhibitory activity against a panel of R5-(virus using the CCR5 coreceptor), X4-(virus using the CXCR4 coreceptor), and R5/X4 HIV-1 laboratory and clinical isolates of the B subtype (median EC50 of 0.04 μM) in culture assays. BMS-378806 is selective for HIV-1 and inactive against HIV-2, SIV and a panel of other viruses, and exhibits no significant cytotoxicity in the 14 cell types tested (concentration for 50% reduction of cell growth, >225 μM). Mechanism of action studies demonstrated that BMS-378806 binds to gp120 and inhibits the interactions of the HIV-1 envelope protein to cellular CD4 receptors. Further confirmation that BMS-378806 targets the envelope in infected cells was obtained through the isolation of resistant variants and the mapping of resistance substitutions to the HIV-1 envelope. In particular, two substitutions, M426L and M475I, are situated in the CD4 binding pocket of gp120. Recombinant HIV-1 carrying these two substitutions demonstrated significantly reduced susceptibility to compound inhibition. BMS-378806 displays many favorable pharmacological traits, such as low protein binding, minimal human serum effect on anti-HIV-1 potency, good oral bioavailability in animal species, and a clean safety profile in initial animal toxicology studies. Together, the data show that BMS-378806 is a representative of a new class of HIV inhibitors that has the potential to become a valued addition to our current armamentarium of antiretroviral drugs. PMID:12930892

  7. Early Infection HIV-1 Envelope V1-V2 Genotypes Do Not Enhance Binding or Replication in Cells Expressing High Levels of α4β7 Integrin

    PubMed Central

    Etemad, Behzad; Gonzalez, Oscar A.; McDonough, Sean; Pena-Cruz, Victor; Sagar, Manish

    2013-01-01

    It has been postulated that HIV-1 envelope properties, such as shorter and less glycosylated V1-V2 loops commonly observed among non-subtype B early – transmitted viruses, promote utilization of the gut homing integrin α4β7. This property potentially confers an advantage to some HIV-1 variants early after acquisition. We found that replication competent recombinant viruses incorporating HIV-1 subtype A compact and less glycosylated early versus chronic phase V1-V2 loops demonstrated no significant difference in binding to α4β7 high CD8+ T cells or replication in α4β7 high CD4+ T cells. Integrin α4β7 usage does not select for shorter less glycosylated envelopes during transmission. PMID:23797693

  8. Early infection HIV-1 envelope V1-V2 genotypes do not enhance binding or replication in cells expressing high levels of α4β7 integrin.

    PubMed

    Etemad, Behzad; Gonzalez, Oscar A; McDonough, Sean; Pena-Cruz, Victor; Sagar, Manish

    2013-11-01

    It has been postulated that HIV-1 envelope properties, such as shorter and less-glycosylated V1-V2 loops commonly observed among non-subtype B early-transmitted viruses, promote utilization of the gut homing integrin α4β7. This property potentially confers an advantage to some HIV-1 variants early after acquisition. We found that replication-competent recombinant viruses incorporating HIV-1 subtype A compact and less-glycosylated early versus chronic phase V1-V2 loops demonstrated no significant difference in binding to α4β7 high CD8⁺ T cells or replication in α4β7 high CD4⁺ T cells. Integrin α4β7 usage does not select for shorter less-glycosylated envelopes during transmission. PMID:23797693

  9. Single-Agent Tenofovir versus Combination Emtricitabine/Tenofovir for Pre-Exposure Prophylaxis against HIV-1 Acquisition: A Randomized Trial

    PubMed Central

    Baeten, Jared M.; Donnell, Deborah; Mugo, Nelly R.; Ndase, Patrick; Thomas, Katherine K.; Campbell, James D.; Wangisi, Jonathan; Tappero, Jordan W.; Bukusi, Elizabeth A.; Cohen, Craig R.; Katabira, Elly; Ronald, Allan; Tumwesigye, Elioda; Were, Edwin; Fife, Kenneth H.; Kiarie, James; Farquhar, Carey; John-Stewart, Grace; Kidoguchi, Lara; Coombs, Robert W.; Hendrix, Craig; Marzinke, Mark A.; Frenkel, Lisa; Haberer, Jessica E.; Bangsberg, David; Celum, Connie

    2014-01-01

    SUMMARY Background Antiretroviral pre-exposure prophylaxis (PrEP), using daily oral tenofovir disoproxil fumarate (TDF) or TDF in combination with emtricitabine (FTC/TDF), has been demonstrated to be efficacious for HIV-1 prevention. While the use of multiple antiretroviral agents is essential for effective HIV-1 treatment, multiple agents may not be required for effective prophylaxis. The relative efficacy of single-agent TDF versus combination FTC/TDF PrEP has not been directly assessed. Methods We conducted a randomized, double-blind, placebo-controlled three-arm trial of daily oral TDF and FTC/TDF PrEP among HIV-1 uninfected members of heterosexual HIV-1 serodiscordant couples from Kenya and Uganda. After an interim review, the trial’s placebo arm was discontinued due to demonstration of PrEP efficacy, and the results of each active PrEP agent compared to placebo were reported (TDF 67%, FTC/TDF 75%). Thereafter, the active arms were continued, and participants initially randomized to placebo were offered re-randomization to TDF or FTC/TDF PrEP. Findings 4410 couples received TDF or FTC/TDF PrEP and were followed for HIV-1 acquisition. Of 52 incident HIV-1 infections, 31 were among those assigned TDF (incidence 0.71 per 100 person-years) and 21 were among those assigned FTC/TDF (incidence 0.48 per 100 person-years); for comparison, HIV-1 incidence in the placebo arm prior to its discontinuation was 2.00 per 100 person-years. HIV-1 prevention efficacy for FTC/TDF compared to TDF alone was not statistically significantly different: HR 0.67, 95% 0.39–1.17, p=0.16. Detection of tenofovir in plasma samples, compared to no detection and as measured in seroconverters and a subset of non-seroconverters, was associated with an 85% relative risk reduction in HIV-1 acquisition for the TDF arm and 93% for the FTC/TDF arm (both p<0.0001). Interpretation These results do not rule out the potential for a modest difference in HIV-1 protection for TDF compared to FTC

  10. The Role of Interleukin-23 in the Early Development of Emphysema in HIV1+ Smokers

    PubMed Central

    Barjaktarevic, Igor Z.; Crystal, Ronald G.

    2016-01-01

    Rationale. Matrix metalloproteinase-9 (MMP-9) expression is upregulated in alveolar macrophages (AM) of HIV1+ smokers who develop emphysema. Knowing that lung epithelial lining fluid (ELF) of HIV1+ smokers contains increased levels of inflammatory cytokines compared to HIV1− smokers, we hypothesized that upregulation of lung cytokines in HIV1+ smokers may be functionally related to increased MMP-9 expression. Methods. Cytokine arrays evaluated cytokine protein levels in ELF obtained from 5 groups of individuals: HIV1− healthy nonsmokers, HIV1− healthy smokers, HIV1− smokers with low diffusing capacity (DLCO), HIV1+ nonsmokers, and HIV1+ smokers with low DLCO. Results. Increased levels of the Th17 related cytokine IL-23 were found in HIV1− smokers with low DLCO and HIV1+ smokers and nonsmokers. Relative IL-23 gene expression was increased in AM of HIV1+ individuals, with greater expression in AM of HIV1+ smokers with low DLCO. Infection with HIV1 in vitro induced IL-23 expression in normal AM. IL-23 stimulation of AM/lymphocyte cocultures in vitro induced upregulation of MMP-9. Lung T lymphocytes express receptor IL-23R and interact with AM in order to upregulate MMP-9. Conclusion. This mechanism may contribute to the increased tissue destruction in the lungs of HIV1+ smokers and suggests that Th17 related inflammation may play a role. PMID:27446965

  11. The Role of Interleukin-23 in the Early Development of Emphysema in HIV1(+) Smokers.

    PubMed

    Barjaktarevic, Igor Z; Crystal, Ronald G; Kaner, Robert J

    2016-01-01

    Rationale. Matrix metalloproteinase-9 (MMP-9) expression is upregulated in alveolar macrophages (AM) of HIV1(+) smokers who develop emphysema. Knowing that lung epithelial lining fluid (ELF) of HIV1(+) smokers contains increased levels of inflammatory cytokines compared to HIV1(-) smokers, we hypothesized that upregulation of lung cytokines in HIV1(+) smokers may be functionally related to increased MMP-9 expression. Methods. Cytokine arrays evaluated cytokine protein levels in ELF obtained from 5 groups of individuals: HIV1(-) healthy nonsmokers, HIV1(-) healthy smokers, HIV1(-) smokers with low diffusing capacity (DLCO), HIV1(+) nonsmokers, and HIV1(+) smokers with low DLCO. Results. Increased levels of the Th17 related cytokine IL-23 were found in HIV1(-) smokers with low DLCO and HIV1(+) smokers and nonsmokers. Relative IL-23 gene expression was increased in AM of HIV1(+) individuals, with greater expression in AM of HIV1(+) smokers with low DLCO. Infection with HIV1 in vitro induced IL-23 expression in normal AM. IL-23 stimulation of AM/lymphocyte cocultures in vitro induced upregulation of MMP-9. Lung T lymphocytes express receptor IL-23R and interact with AM in order to upregulate MMP-9. Conclusion. This mechanism may contribute to the increased tissue destruction in the lungs of HIV1(+) smokers and suggests that Th17 related inflammation may play a role. PMID:27446965

  12. Genotype dependent QSAR for HIV-1 protease inhibition.

    PubMed

    Boutton, Carlo W; De Bondt, Hendrik L; De Jonge, Marc R

    2005-03-24

    The development of drug-resistant viruses limits the therapeutic success of anti-HIV therapies. Some of these genetic HIV-variants display complex mutational patterns in their pol gene that codes for protease and reverse transcriptase, the most investigated molecular targets for antiretroviral therapy. In this paper, we present a computational structure-based approach to predict the resistance of a HIV-1 protease strain to amprenavir by calculating the interaction energy of the drug with HIV-1 protease. By considering the interaction energy per residue, we can identify what residue mutations contribute to drug-resistance. This approach is presented here as a structure-based tool for the prediction of resistance of HIV-1 protease toward amprenavir, with a view to use the drug-protein interaction-energy pattern in a lead-optimization procedure for the discovery of new anti-HIV drugs. PMID:15771454

  13. Structural basis for membrane anchoring of HIV-1 envelope spike.

    PubMed

    Dev, Jyoti; Park, Donghyun; Fu, Qingshan; Chen, Jia; Ha, Heather Jiwon; Ghantous, Fadi; Herrmann, Tobias; Chang, Weiting; Liu, Zhijun; Frey, Gary; Seaman, Michael S; Chen, Bing; Chou, James J

    2016-07-01

    HIV-1 envelope spike (Env) is a type I membrane protein that mediates viral entry. We used nuclear magnetic resonance to determine an atomic structure of the transmembrane (TM) domain of HIV-1 Env reconstituted in bicelles that mimic a lipid bilayer. The TM forms a well-ordered trimer that protects a conserved membrane-embedded arginine. An amino-terminal coiled-coil and a carboxyl-terminal hydrophilic core stabilize the trimer. Individual mutations of conserved residues did not disrupt the TM trimer and minimally affected membrane fusion and infectivity. Major changes in the hydrophilic core, however, altered the antibody sensitivity of Env. These results show how a TM domain anchors, stabilizes, and modulates a viral envelope spike and suggest that its influence on Env conformation is an important consideration for HIV-1 immunogen design. PMID:27338706

  14. Immunological biomarkers predict HIV-1 viral rebound after treatment interruption

    PubMed Central

    Hurst, Jacob; Hoffmann, Matthias; Pace, Matthew; Williams, James P.; Thornhill, John; Hamlyn, Elizabeth; Meyerowitz, Jodi; Willberg, Chris; Koelsch, Kersten K.; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Cooper, David A.; Schechter, Mauro; Tambussi, Giuseppe; Fidler, Sarah; Babiker, Abdel; Weber, Jonathan; Kelleher, Anthony D.; Phillips, Rodney E.; Frater, John

    2015-01-01

    Treatment of HIV-1 infection with antiretroviral therapy (ART) in the weeks following transmission may induce a state of ‘post-treatment control' (PTC) in some patients, in whom viraemia remains undetectable when ART is stopped. Explaining PTC could help our understanding of the processes that maintain viral persistence. Here we show that immunological biomarkers can predict time to viral rebound after stopping ART by analysing data from a randomized study of primary HIV-1 infection incorporating a treatment interruption (TI) after 48 weeks of ART (the SPARTAC trial). T-cell exhaustion markers PD-1, Tim-3 and Lag-3 measured prior to ART strongly predict time to the return of viraemia. These data indicate that T-cell exhaustion markers may identify those latently infected cells with a higher proclivity to viral transcription. Our results may open new avenues for understanding the mechanisms underlying PTC, and eventually HIV-1 eradication. PMID:26449164

  15. Immunological biomarkers predict HIV-1 viral rebound after treatment interruption.

    PubMed

    Hurst, Jacob; Hoffmann, Matthias; Pace, Matthew; Williams, James P; Thornhill, John; Hamlyn, Elizabeth; Meyerowitz, Jodi; Willberg, Chris; Koelsch, Kersten K; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Cooper, David A; Schechter, Mauro; Tambussi, Giuseppe; Fidler, Sarah; Babiker, Abdel; Weber, Jonathan; Kelleher, Anthony D; Phillips, Rodney E; Frater, John

    2015-01-01

    Treatment of HIV-1 infection with antiretroviral therapy (ART) in the weeks following transmission may induce a state of 'post-treatment control' (PTC) in some patients, in whom viraemia remains undetectable when ART is stopped. Explaining PTC could help our understanding of the processes that maintain viral persistence. Here we show that immunological biomarkers can predict time to viral rebound after stopping ART by analysing data from a randomized study of primary HIV-1 infection incorporating a treatment interruption (TI) after 48 weeks of ART (the SPARTAC trial). T-cell exhaustion markers PD-1, Tim-3 and Lag-3 measured prior to ART strongly predict time to the return of viraemia. These data indicate that T-cell exhaustion markers may identify those latently infected cells with a higher proclivity to viral transcription. Our results may open new avenues for understanding the mechanisms underlying PTC, and eventually HIV-1 eradication.

  16. Lipids and Membrane Microdomains in HIV-1 Replication

    PubMed Central

    Waheed, Abdul A.; Freed, Eric O.

    2009-01-01

    Several critical steps in the replication cycle of human immunodeficiency virus type 1 (HIV-1) – entry, assembly and budding – are complex processes that take place at the plasma membrane of the host cell. A growing body of data indicates that these early and late steps in HIV-1 replication take place in specialized plasma membrane microdomains, and that many of the viral and cellular components required for entry, assembly, and budding are concentrated in these microdomains. In particular, a number of studies have shown that cholesterol- and sphingolipid-enriched microdomains known as lipid rafts play important roles in multiple steps in the virus replication cycle. In this review, we provide an overview of what is currently known about the involvement of lipids and membrane microdomains in HIV-1 replication. PMID:19383519

  17. HIV-1 and the immune response to TB

    PubMed Central

    Walker, Naomi F; Meintjes, Graeme; Wilkinson, Robert J

    2013-01-01

    TB causes 1.4 million deaths annually. HIV-1 infection is the strongest risk factor for TB. The characteristic immunological effect of HIV is on CD4 cell count. However, the risk of TB is elevated in HIV-1 infected individuals even in the first few years after HIV acquisition and also after CD4 cell counts are restored with antiretroviral therapy. In this review, we examine features of the immune response to TB and how this is affected by HIV-1 infection and vice versa. We discuss how the immunology of HIV–TB coinfection impacts on the clinical presentation and diagnosis of TB, and how antiretroviral therapy affects the immune response to TB, including the development of TB immune reconstitution inflammatory syndrome. We highlight important areas of uncertainty and future research needs. PMID:23653664

  18. Anti-HIV-1 protease- and HIV-1 integrase activities of Thai medicinal plants known as Hua-Khao-Yen.

    PubMed

    Tewtrakul, Supinya; Itharat, Arunporn; Rattanasuwan, Pranee

    2006-04-21

    Ethanolic- and water extracts from five species of Thai medicinal plants known as Hua-Khao-Yen were tested for their inhibitory effects against HIV-1 protease (HIV-PR) and HIV-1 integrase (HIV-1 IN). The result revealed that the ethanolic (EtOH) extract of Smilax corbularia exhibited anti-HIV-1 IN activity with an IC50 value of 1.9 microg/ml, followed by the water extract of Dioscorea birmanica (IC50 = 4.5 microg/ml), the EtOH extract of Dioscorea birmanica (IC50 = 4.7 microg/ml), the water extract of Smilax corbularia (IC50 = 5.4 microg/ml), the EtOH extract of Smilax glabra (IC50 = 6.7 microg/ml) and the water extract of Smilax glabra (IC50 = 8.5 microg/ml). The extracts of Pygmaeopremna herbacea and Dioscorea membranacea were apparently inactive (IC50 > 100 microg/ml). Interestingly, only the EtOH extract of Dioscorea membranacea showed appreciable activity (IC50 = 48 microg/ml) against HIV-1 PR, while the other extracts possessed mild activity. This result strongly supported the basis for the use of Smilax corbularia and Dioscorea membranacea for AIDS treatment by Thai traditional doctors. PMID:16406414

  19. Selective elimination of HIV-1-infected cells by Env-directed, HIV-1-based virus-like particles

    SciTech Connect

    Peretti, Silvia; Schiavoni, Ilaria; Pugliese, Katherina; Federico, Maurizio . E-mail: federico@iss.it

    2006-02-05

    We recently showed that both replicating and resting cells cultivated with ganciclovir (GCV) were killed when challenged with vesicular stomatitis virus G glycoprotein pseudotyped HIV-1-based virus-like particles (VLPs) carrying the Nef7 (i.e., an HIV-1 Nef mutant incorporating in virions at high levels)/herpes simplex virus-1 thymidine kinase (HSV-TK) fusion product. On this basis, a novel anti-HIV therapeutic approach based on Nef7/TK VLPs expressing X4 or R5 HIV cell receptor complexes has been attempted. We here report that (CD4-CXCR4) and (CD4-CCR5) Nef7-based VLPs efficiently enter cells infected by X4- or R5-tropic HIV-1 strains, respectively. Importantly, the delivery of the VLP-associated Nef7/TK led to cell death upon GCV treatment. Of interest, VLPs were effective also against non-replicating, HIV-1-infected primary human monocyte-derived macrophages. HIV-targeted VLPs represent a promising candidate for the treatment of persistently HIV-1-infected cells that are part of virus reservoirs resistant to HAART therapies.

  20. No SEVI-mediated enhancement of rectal HIV-1 transmission of HIV-1 in two humanized mouse cohorts.

    PubMed

    Van Dis, Erik S; Moore, Tyler C; Lavender, Kerry J; Messer, Ronald J; Keppler, Oliver T; Verheyen, Jens; Dittmer, Ulf; Hasenkrug, Kim J

    2016-01-15

    Amyloid fibrils from semen-derived peptide (SEVI) enhance HIV-1 infectivity in vitro but the ability of SEVI to mediate enhancement of HIV infection in vivo has not been tested. In this study we used immunodeficient mice reconstituted with human immune systems to test for in vivo enhancement of HIV-1 transmission. This mouse model supports mucosal transmission of HIV-1 via the intrarectal route leading to productive infection. In separate experiments with humanized mouse cohorts reconstituted with two different donor immune systems, high dose HIV-1JR-CSF that had been incubated with SEVI amyloid fibrils at physiologically relevant concentrations did not show an increased incidence of infection compared to controls. In addition, SEVI failed to enhance rectal transmission with a reduced concentration of HIV-1. Although we confirmed potent SEVI-mediated enhancement of HIV infectivity in vitro, this model showed no evidence that it plays a role in the much more complex situation of in vivo transmission. PMID:26609939

  1. 2´,3´-Dialdehyde of ATP, ADP, and adenosine inhibit HIV-1 reverse transcriptase and HIV-1 replication.

    PubMed

    Schachter, Julieta; Valadao, Ana Luiza Chaves; Aguiar, Renato Santana; Barreto-de-Souza, Victor; Rossi, Atila Duque; Arantes, Pablo Ricardo; Verli, Hugo; Quintana, Paula Gabriela; Heise, Norton; Tanuri, Amilcar; Bou-Habib, Dumith Chequer; Persechini, Pedro Muanis

    2014-01-01

    The 2´3´-dialdehyde of ATP or oxidized ATP (oATP) is a compound known for specifically making covalent bonds with the nucleotide-binding site of several ATP-binding enzymes and receptors. We investigated the effects of oATP and other oxidized purines on HIV-1 infection and we found that this compound inhibits HIV-1 and SIV infection by blocking early steps of virus replication. oATP, oxidized ADP (oADP), and oxidized Adenosine (oADO) impact the natural activity of endogenous reverse transcriptase enzyme (RT) in cell free virus particles and are able to inhibit viral replication in different cell types when added to the cell cultures either before or after infection. We used UFLC-UV to show that both oADO and oATP can be detected in the cell after being added in the extracellular medium. oATP also suppresses RT activity and replication of the HIV-1 resistant variants M184V and T215Y. We conclude that oATP, oADP and oADO display anti HIV-1 activity that is at in least in part due to inhibitory activity on HIV-1 RT.

  2. A New Approach to Produce HIV-1 Envelope Trimers

    PubMed Central

    AlSalmi, Wadad; Mahalingam, Marthandan; Ananthaswamy, Neeti; Hamlin, Christopher; Flores, Dalia; Gao, Guofen; Rao, Venigalla B.

    2015-01-01

    The trimeric envelope spike of HIV-1 mediates virus entry into human cells. The exposed part of the trimer, gp140, consists of two noncovalently associated subunits, gp120 and gp41 ectodomain. A recombinant vaccine that mimics the native trimer might elicit entry-blocking antibodies and prevent virus infection. However, preparation of authentic HIV-1 trimers has been challenging. Recently, an affinity column containing the broadly neutralizing antibody 2G12 has been used to capture recombinant gp140 and prepare trimers from clade A BG505 that naturally produces stable trimers. However, this antibody-based approach may not be as effective for the diverse HIV-1 strains with different epitope signatures. Here, we report a new and simple approach to produce HIV-1 envelope trimers. The C terminus of gp140 was attached to Strep-tag II with a long linker separating the tag from the massive trimer base and glycan shield. This allowed capture of nearly homogeneous gp140 directly from the culture medium. Cleaved, uncleaved, and fully or partially glycosylated trimers from different clade viruses were produced. Extensive biochemical characterizations showed that cleavage of gp140 was not essential for trimerization, but it triggered a conformational change that channels trimers into correct glycosylation pathways, generating compact three-blade propeller-shaped trimers. Uncleaved trimers entered aberrant pathways, resulting in hyperglycosylation, nonspecific cross-linking, and conformational heterogeneity. Even the cleaved trimers showed microheterogeneity in gp41 glycosylation. These studies established a broadly applicable HIV-1 trimer production system as well as generating new insights into their assembly and maturation that collectively bear on the HIV-1 vaccine design. PMID:26088135

  3. Mechanisms for macrophage-mediated HIV-1 induction.

    PubMed

    Devadas, Krishnakumar; Hardegen, Neil J; Wahl, Larry M; Hewlett, Indira K; Clouse, Kathleen A; Yamada, Kenneth M; Dhawan, Subhash

    2004-12-01

    Viral latency is a long-term pathogenic condition in patients infected with HIV-1. Low but sustained virus replication in chronically infected cells can be activated by stimulation with proinflammatory cytokines such as TNF-alpha, IL-1 beta, or other host factors. However, the precise mechanism by which cellular activation induces latently infected cells to produce virions has remained unclear. In the present report, we present evidence that activation of HIV-1 replication in latently infected U1 or ACH2 cells by human macrophages is mediated by a rapid nuclear localization of NF-kappaB p50/p65 dimer with concomitant increased expression of proinflammatory cytokines. Multiplexed RT-PCR amplification of mRNA isolated from cocultures of macrophages and U1 and ACH2 cells showed significant induction of IL-1beta, IL-6, IL-8, TNF-alpha, and TGF-beta expression within 3 h of coincubation. Fixation of macrophages, U-1, or ACH2 cells with paraformaldehyde before coculture completely abrogated the induction of NF-kappaB subunits and HIV-1 replication, suggesting that cooperative interaction between the two cell types is an essential process for cellular activation. Pretreatment of macrophage-U1 or macrophage-ACH2 cocultures with neutralizing anti-TNF-alpha Ab down-regulated the replication of HIV-1. In addition, pretreatment of macrophage-U1 or macrophage-ACH2 cocultures with the NF-kappaB inhibitor (E)3-[(4-methylphenyl)sulfonyl]-2-propenenitrile (BAY 11-7082) prevented the induction of cytokine expression, indicating a pivotal role of NF-kappaB-mediated signaling in the reactivation of HIV-1 in latently infected cells by macrophages. These results provide a mechanism by which macrophages induce HIV-1 replication in latently infected cells.

  4. Measuring glutathione redox potential of HIV-1-infected macrophages.

    PubMed

    Bhaskar, Ashima; Munshi, MohamedHusen; Khan, Sohrab Zafar; Fatima, Sadaf; Arya, Rahul; Jameel, Shahid; Singh, Amit

    2015-01-01

    Redox signaling plays a crucial role in the pathogenesis of human immunodeficiency virus type-1 (HIV-1). The majority of HIV redox research relies on measuring redox stress using invasive technologies, which are unreliable and do not provide information about the contributions of subcellular compartments. A major technological leap emerges from the development of genetically encoded redox-sensitive green fluorescent proteins (roGFPs), which provide sensitive and compartment-specific insights into redox homeostasis. Here, we exploited a roGFP-based specific bioprobe of glutathione redox potential (E(GSH); Grx1-roGFP2) and measured subcellular changes in E(GSH) during various phases of HIV-1 infection using U1 monocytic cells (latently infected U937 cells with HIV-1). We show that although U937 and U1 cells demonstrate significantly reduced cytosolic and mitochondrial E(GSH) (approximately -310 mV), active viral replication induces substantial oxidative stress (E(GSH) more than -240 mV). Furthermore, exposure to a physiologically relevant oxidant, hydrogen peroxide (H2O2), induces significant deviations in subcellular E(GSH) between U937 and U1, which distinctly modulates susceptibility to apoptosis. Using Grx1-roGFP2, we demonstrate that a marginal increase of about ∼25 mV in E(GSH) is sufficient to switch HIV-1 from latency to reactivation, raising the possibility of purging HIV-1 by redox modulators without triggering detrimental changes in cellular physiology. Importantly, we show that bioactive lipids synthesized by clinical drug-resistant isolates of Mycobacterium tuberculosis reactivate HIV-1 through modulation of intracellular E(GSH). Finally, the expression analysis of U1 and patient peripheral blood mononuclear cells demonstrated a major recalibration of cellular redox homeostatic pathways during persistence and active replication of HIV.

  5. Evolutionary history of HIV-1 subtype B and CRF01_AE transmission clusters among men who have sex with men (MSM) in Kuala Lumpur, Malaysia.

    PubMed

    Ng, Kim Tien; Ong, Lai Yee; Lim, Sin How; Takebe, Yutaka; Kamarulzaman, Adeeba; Tee, Kok Keng

    2013-01-01

    HIV-1 epidemics among men who have sex with men (MSM) continue to expand in developed and developing countries. Although HIV infection in MSM is amongst the highest of the key affected populations in many countries in Southeast Asia, comprehensive molecular epidemiological study of HIV-1 among MSM remains inadequate in the region including in Malaysia. Here, we reported the phylodynamic profiles of HIV-1 genotypes circulating among MSM population in Kuala Lumpur, Malaysia. A total of n = 459 newly-diagnosed treatment-naïve consenting subjects were recruited between March 2006 and August 2012, of whom 87 (18.9%) were self-reported MSM. Transmitted drug resistance mutations were absent in these isolates. Cumulatively, phylogenetic reconstructions of the pro-rt gene (HXB2∶2253-3275) showed that HIV-1 subtype B and CRF01_AE were predominant and contributed to approximately 80% of the total HIV-1 infection among MSM. In addition to numerous unique transmission lineages within these genotypes, twelve monophyletic transmission clusters of different sizes (2-7 MSM sequences, supported by posterior probability value of 1) were identified in Malaysia. Bayesian coalescent analysis estimated that the divergence times for these clusters were mainly dated between 1995 and 2005 with four major transmission clusters radiating at least 12 years ago suggesting that active spread of multiple sub-epidemic clusters occurred during this period. The changes in effective population size of subtype B showed an exponential growth within 5 years between 1988 and 1993, while CRF01_AE lineage exhibited similar expansion between 1993 and 2003. Our study provides the first insight of the phylodynamic profile of HIV-1 subtype B and CRF01_AE circulating among MSM population in Kuala Lumpur, Malaysia, unravelling the importance of understanding transmission behaviours as well as evolutionary history of HIV-1 in assessing the risk of outbreak or epidemic expansion.

  6. HIV-1 neutralization profile and plant-based recombinant expression of actinohivin, an Env glycan-specific lectin devoid of T-cell mitogenic activity.

    PubMed

    Matoba, Nobuyuki; Husk, Adam S; Barnett, Brian W; Pickel, Michelle M; Arntzen, Charles J; Montefiori, David C; Takahashi, Atsushi; Tanno, Kazunobu; Omura, Satoshi; Cao, Huyen; Mooney, Jason P; Hanson, Carl V; Tanaka, Haruo

    2010-01-01

    The development of a topical microbicide blocking the sexual transmission of HIV-1 is urgently needed to control the global HIV/AIDS pandemic. The actinomycete-derived lectin actinohivin (AH) is highly specific to a cluster of high-mannose-type glycans uniquely found on the viral envelope (Env). Here, we evaluated AH's candidacy toward a microbicide in terms of in vitro anti-HIV-1 activity, potential side effects, and recombinant producibility. Two validated assay systems based on human peripheral blood mononuclear cell (hPBMC) infection with primary isolates and TZM-bl cell infection with Env-pseudotyped viruses were employed to characterize AH's anti-HIV-1 activity. In hPMBCs, AH exhibited nanomolar neutralizing activity against primary viruses with diverse cellular tropisms, but did not cause mitogenicity or cytotoxicity that are often associated with other anti-HIV lectins. In the TZM-bl-based assay, AH showed broad anti-HIV-1 activity against clinically-relevant, mucosally transmitting strains of clades B and C. By contrast, clade A viruses showed strong resistance to AH. Correlation analysis suggested that HIV-1's AH susceptibility is significantly linked to the N-glycans at the Env C2 and V4 regions. For recombinant (r)AH expression, we evaluated a tobacco mosaic virus-based system in Nicotiana benthamiana plants as a means to facilitate molecular engineering and cost-effective mass production. Biochemical analysis and an Env-mediated syncytium formation assay demonstrated high-level expression of functional rAH within six days. Taken together, our study revealed AH's cross-clade anti-HIV-1 activity, apparent lack of side effects common to lectins, and robust producibility using plant biotechnology. These findings justify further efforts to develop rAH toward a candidate HIV-1 microbicide. PMID:20559567

  7. Mice Transgenic for CD4-Specific Human CD4, CCR5 and Cyclin T1 Expression: A New Model for Investigating HIV-1 Transmission and Treatment Efficacy

    PubMed Central

    Zheng, Jian Hua; Zhang, Cong; Chen, Ken; Dutta, Monica; Deneroff, Kathryn; Ochsenbauer, Christina; Kappes, John C.; Littman, Dan R.; Goldstein, Harris

    2013-01-01

    R-expressing HIV-IMC expressing transmitted/founder and clade A/E and C Envs will provide researchers with a highly accessible pre-clinical in vivo HIV-1-infection model to study HIV-1 acquisition, treatment, and prevention. PMID:23691059

  8. Constructing the Average Natural History of HIV-1 Infection

    NASA Astrophysics Data System (ADS)

    Diambra, L.; Capurro, A.; Malta, C. P.

    2007-05-01

    Many aspects of the natural course of the HIV-1 infection remains unclear, despite important efforts towards understanding its long-term dynamics. Using a scaling approach that places progression markers (viral load, CD4+, CD8+) of many individuals on a single average natural course of disease progression, we introduce the concept of inter-individual scaling and time scaling. Our quantitative assessment of the natural course of HIV-1 infection indicates that the dynamics of the evolution for the individual that developed AIDS (opportunistic infections) is different from that of the individual that did not develop AIDS. This means that the rate of progression is not relevant for the infection evolution.

  9. Can we cure HIV-1-associated nephropathy in transgenic mice?

    PubMed

    Ray, Patricio E

    2012-05-01

    HIV-1-associated nephropathy (HIVAN) is a rapidly progressive form of focal segmental glomerulosclerosis. HIV transgenic mice can develop a HIVAN-like renal disease. Zhong et al. show that the oral administration of a cyclic nucleotide phosphodiesterase 4 inhibitor and a retinoic acid receptor-α agonist can prevent the development of HIVAN in transgenic mice, acting through a cAMP-dependent mechanism that is independent of HIV-1 genes. These findings suggest that endogenous host factors play a critical role in HIVAN.

  10. Can we cure HIV-1 associated nephropathy in transgenic mice?

    PubMed Central

    Ray, Patricio E.

    2012-01-01

    HIV-1 associated nephropathy is a rapidly progressive form of focal segmental glomerulosclerosis typically seen in patients of African ancestry. HIV-transgenic mice can develop an HIVAN-like renal disease. Zhong et al. show that the oral administration of a cyclic nucleotide phosphodiesterase 4 inhibitor and a retinoic acid receptor-alpha agonist can prevent the development of HIVAN in transgenic mice, acting through a cAMP dependent mechanism that is independent of HIV-1 genes. These findings suggest that endogenous host factors play a critical role in HIVAN. PMID:22499139

  11. Dual Neonate Vaccine Platform against HIV-1 and M. tuberculosis

    PubMed Central

    Hopkins, Richard; Bridgeman, Anne; Joseph, Joan; Gilbert, Sarah C.; McShane, Helen; Hanke, Tomáš

    2011-01-01

    Acquired immunodeficiency syndrome and tuberculosis (TB) are two of the world's most devastating diseases. The first vaccine the majority of infants born in Africa receive is Mycobacterium bovis bacillus Calmette-Guérin (BCG) as a prevention against TB. BCG protects against disseminated disease in the first 10 years of life, but provides a variable protection against pulmonary TB and enhancing boost delivered by recombinant modified vaccinia virus Ankara (rMVA) expressing antigen 85A (Ag85A) of M. tuberculosis is currently in phase IIb evaluation in African neonates. If the newborn's mother is positive for human immunodeficiency virus type 1 (HIV-1), the baby is at high risk of acquiring HIV-1 through breastfeeding. We suggested that a vaccination consisting of recombinant BCG expressing HIV-1 immunogen administered at birth followed by a boost with rMVA sharing the same immunogen could serve as a strategy for prevention of mother-to-child transmission of HIV-1 and rMVA expressing an African HIV-1-derived immunogen HIVA is currently in phase I trials in African neonates. Here, we aim to develop a dual neonate vaccine platform against HIV-1 and TB consisting of BCG.HIVA administered at birth followed by a boost with MVA.HIVA.85A. Thus, mMVA.HIVA.85A and sMVA.HIVA.85A vaccines were constructed, in which the transgene transcription is driven by either modified H5 or short synthetic promoters, respectively, and tested for immunogenicity alone and in combination with BCG.HIVA222. mMVA.HIVA.85A was produced markerless and thus suitable for clinical manufacture. While sMVA.HIVA.85A expressed higher levels of the immunogens, it was less immunogenic than mMVA.HIVA.85A in BALB/c mice. A BCG.HIVA222–mMVA.HIVA.85A prime-boost regimen induced robust T cell responses to both HIV-1 and M. tuberculosis. Therefore, proof-of-principle for a dual anti-HIV-1/M. tuberculosis infant vaccine platform is established. Induction of immune responses against these pathogens soon after

  12. The Latent Reservoir for HIV-1: How Immunologic Memory and Clonal Expansion Contribute to HIV-1 Persistence.

    PubMed

    Murray, Alexandra J; Kwon, Kyungyoon J; Farber, Donna L; Siliciano, Robert F

    2016-07-15

    Combination antiretroviral therapy (ART) for HIV-1 infection reduces plasma virus levels to below the limit of detection of clinical assays. However, even with prolonged suppression of viral replication with ART, viremia rebounds rapidly after treatment interruption. Thus, ART is not curative. The principal barrier to cure is a remarkably stable reservoir of latent HIV-1 in resting memory CD4(+) T cells. In this review, we consider explanations for the remarkable stability of the latent reservoir. Stability does not appear to reflect replenishment from new infection events but rather normal physiologic processes that provide for immunologic memory. Of particular importance are proliferative processes that drive clonal expansion of infected cells. Recent evidence suggests that in some infected cells, proliferation is a consequence of proviral integration into host genes associated with cell growth. Efforts to cure HIV-1 infection by targeting the latent reservoir may need to consider the potential of latently infected cells to proliferate.

  13. The Latent Reservoir for HIV-1: How Immunologic Memory and Clonal Expansion Contribute to HIV-1 Persistence.

    PubMed

    Murray, Alexandra J; Kwon, Kyungyoon J; Farber, Donna L; Siliciano, Robert F

    2016-07-15

    Combination antiretroviral therapy (ART) for HIV-1 infection reduces plasma virus levels to below the limit of detection of clinical assays. However, even with prolonged suppression of viral replication with ART, viremia rebounds rapidly after treatment interruption. Thus, ART is not curative. The principal barrier to cure is a remarkably stable reservoir of latent HIV-1 in resting memory CD4(+) T cells. In this review, we consider explanations for the remarkable stability of the latent reservoir. Stability does not appear to reflect replenishment from new infection events but rather normal physiologic processes that provide for immunologic memory. Of particular importance are proliferative processes that drive clonal expansion of infected cells. Recent evidence suggests that in some infected cells, proliferation is a consequence of proviral integration into host genes associated with cell growth. Efforts to cure HIV-1 infection by targeting the latent reservoir may need to consider the potential of latently infected cells to proliferate. PMID:27382129

  14. Topical Tenofovir Disoproxil Fumarate Nanoparticles Prevent HIV-1 Vaginal Transmission in a Humanized Mouse Model.

    PubMed

    Destache, Christopher J; Mandal, Subhra; Yuan, Zhe; Kang, Guobin; Date, Abhijit A; Lu, Wuxun; Shibata, Annemarie; Pham, Rachel; Bruck, Patrick; Rezich, Michael; Zhou, You; Vivekanandan, Renuga; Fletcher, Courtney V; Li, Qingsheng

    2016-06-01

    Preexposure prophylaxis (PrEP) with 1% tenofovir (TFV) vaginal gel has failed in clinical trials. To improve TFV efficacy in vaginal gel, we formulated tenofovir disoproxil fumarate nanoparticles in a thermosensitive (TMS) gel (TDF-NP-TMS gel). TDF-NPs were fabricated using poly(lactic-co-glycolic acid) (PLGA) polymer and an ion-pairing agent by oil-in-water emulsification. The efficacy of TDF-NP-TMS gel was tested in humanized bone marrow-liver-thymus (hu-BLT) mice. Hu-BLT mice in the treatment group (Rx; n = 15) were administered TDF-NP-TMS gel intravaginally, having TDF at 0.1%, 0.5%, and 1% (wt/vol) concentrations, whereas the control (Ctr; n = 8) group received a blank TMS gel. All Rx mice (0.1% [n = 4], 0.5% [n = 6], and 1% [n = 5]) were vaginally challenged with two transmitted/founder (T/F) HIV-1 strains (2.5 × 10(5) 50% tissue culture infectious doses). Rx mice were challenged at 4 h (0.1%), 24 h (0.5%), and 7 days (1%) posttreatment (p.t.) and Ctr mice were challenged at 4 h p.t. Blood was drawn weekly for 4 weeks postinoculation (p.i.) for plasma viral load (pVL) using reverse transcription-quantitative PCR. Ctr mice had positive pVL within 2 weeks p.i. Rx mice challenged at 4 h and 24 h showed 100% protection and no detectable pVL throughout the 4 weeks of follow-up (P = 0.009; Mantel-Cox test). Mice challenged at 7 days were HIV-1 positive at 14 days p.i. Further, HIV-1 viral RNA (vRNA) in vaginal and spleen tissues of Rx group mice with negative pVL were examined using an in situ hybridization (ISH) technique. The detection of vRNA was negative in all Rx mice studied. The present studies elucidate TDF-NP-TMS gel as a long-acting, coitus-independent HIV-1 vaginal protection modality. PMID:27044548

  15. HIV-1 Diversity, Transmission Dynamics and Primary Drug Resistance in Angola

    PubMed Central

    Bártolo, Inês; Zakovic, Suzana; Martin, Francisco; Palladino, Claudia; Carvalho, Patrícia; Camacho, Ricardo; Thamm, Sven; Clemente, Sofia; Taveira, Nuno

    2014-01-01

    Objectives To assess HIV-1 diversity, transmission dynamics and prevalence of transmitted drug resistance (TDR) in Angola, five years after ART scale-up. Methods Population sequencing of the pol gene was performed on 139 plasma samples collected in 2009 from drug-naive HIV-1 infected individuals living in Luanda. HIV-1 subtypes were determined using phylogenetic analysis. Drug resistance mutations were identified using the Calibrated Population Resistance Tool (CPR). Transmission networks were determined using phylogenetic analysis of all Angolan sequences present in the databases. Evolutionary trends were determined by comparison with a similar survey performed in 2001. Results 47.1% of the viruses were pure subtypes (all except B), 47.1% were recombinants and 5.8% were untypable. The prevalence of subtype A decreased significantly from 2001 to 2009 (40.0% to 10.8%, P = 0.0019) while the prevalence of unique recombinant forms (URFs) increased>2-fold (40.0% to 83.1%, P<0.0001). The most frequent URFs comprised untypable sequences with subtypes H (U/H, n = 7, 10.8%), A (U/A, n = 6, 9.2%) and G (G/U, n = 4, 6.2%). Newly identified U/H recombinants formed a highly supported monophyletic cluster suggesting a local and common origin. TDR mutation K103N was found in one (0.7%) patient (1.6% in 2001). Out of the 364 sequences sampled for transmission network analysis, 130 (35.7%) were part of a transmission network. Forty eight transmission clusters were identified; the majority (56.3%) comprised sequences sampled in 2008–2010 in Luanda which is consistent with a locally fuelled epidemic. Very low genetic distance was found in 27 transmission pairs sampled in the same year, suggesting recent transmission events. Conclusions Transmission of drug resistant strains was still negligible in Luanda in 2009, five years after the scale-up of ART. The dominance of small and recent transmission clusters and the emergence of new URFs are consistent with a rising

  16. Maternal human leukocyte antigen-G (HLA-G) genetic variants associate with in utero mother-to-child transmission of HIV-1 in Black South Africans.

    PubMed

    Hong, Heather A; Paximadis, Maria; Gray, Glenda E; Kuhn, Louise; Tiemessen, Caroline T

    2015-03-01

    A 14-bp insertion/deletion (indel) within the 3' untranslated region (3'UTR) that affects HLA-G expression has been associated with HIV-1 mother-to-child transmission (MTCT). However, other 3'UTR single nucleotide polymorphisms (SNPs) that influence HLA-G mRNA stability have been described but not analysed in the context of MTCT, and little is known about the role of HLA-G alleles. We examined HLA-G alleles and 3'UTR SNPs, including the 14-bp indel, in 216 mother-infant pairs from Johannesburg, South Africa. Mother-infant pairs were classified as HIV-1 non-transmitting (NT, n=144) or HIV-1 transmitting (TR, n=72) with either intrapartum (IP, n=29) or in utero (IU, n=19) infected infants. We found HLA-G allele, G(∗)01:01:02 (in strong linkage disequilibrium with the 14-bp insertion) and +3187G SNP were significantly over-represented in IU-TR mothers compared to NT mothers (P=0.036, OR=2.26; P=0.011, OR=2.96, respectively). These findings suggest that maternal HLA-G alleles and/or SNPs that might alter expression of HLA-G potentially influence IU HIV-1 MTCT.

  17. Phylogenetic analysis consistent with a clinical history of sexual transmission of HIV-1 from a single donor reveals transmission of highly distinct variants

    PubMed Central

    2011-01-01

    Background To combat the pandemic of human immunodeficiency virus 1 (HIV-1), a successful vaccine will need to cope with the variability of transmissible viruses. Human hosts infected with HIV-1 potentially harbour many viral variants but very little is known about viruses that are likely to be transmitted, or even if there are viral characteristics that predict enhanced transmission in vivo. We show for the first time that genetic divergence consistent with a single transmission event in vivo can represent several years of pre-transmission evolution. Results We describe a highly unusual case consistent with a single donor transmitting highly related but distinct HIV-1 variants to two individuals on the same evening. We confirm that the clustering of viral genetic sequences, present within each recipient, is consistent with the history of a single donor across the viral env, gag and pol genes by maximum likelihood and Bayesian Markov Chain Monte Carlo based phylogenetic analyses. Based on an uncorrelated, lognormal relaxed clock of env gene evolution calibrated with other datasets, the time since the most recent common ancestor is estimated as 2.86 years prior to transmission (95% confidence interval 1.28 to 4.54 years). Conclusion Our results show that an effective design for a preventative vaccine will need to anticipate extensive HIV-1 diversity within an individual donor as well as diversity at the population level. PMID:21736738

  18. Maternal human leukocyte antigen-G (HLA-G) genetic variants associate with in utero mother-to-child transmission of HIV-1 in Black South Africans

    PubMed Central

    Hong, Heather A.; Paximadis, Maria; Gray, Glenda E.; Kuhn, Louise; Tiemessen, Caroline T.

    2014-01-01

    A 14-bp insertion/deletion (indel) within the 3' untranslated region (3’UTR) that affects HLA-G expression has been associated with HIV-1 mother-to-child transmission (MTCT). However, other 3’UTR single nucleotide polymorphisms (SNPs) that influence HLA-G mRNA stability have been described but not analyzed in the context of MTCT, and little is known about the role of HLA-G alleles. We examined HLA-G alleles and 3’UTR SNPs, including the 14-bp indel, in 216 mother-infant pairs from Johannesburg, South Africa. Mother-infant pairs were classified as HIV-1 non-transmitting (NT, n=144) or HIV-1 transmitting (TR, n=72) with either intrapartum (IP, n=29) or in utero (IU, n=19) infected infants. We found HLA-G allele, G*01:01:02 (in strong linkage disequilibrium with the 14-bp insertion) and +3187G SNP were significantly over-represented in IU-TR mothers compared to NT mothers (P=0.036, OR=2.26; P=0.011, OR=2.96, respectively). These findings suggest that maternal HLA-G alleles and/or SNPs that might alter expression of HLA-G potentially influence IU HIV-1 MTCT. PMID:25541520

  19. Inhibitory Effect of Individual or Combinations of Broadly Neutralizing Antibodies and Antiviral Reagents against Cell-Free and Cell-to-Cell HIV-1 Transmission

    PubMed Central

    Kolodkin-Gal, Dror; Eslamizar, Leila; Owuor, Joshua O.; Mazzola, Emanuele; Gonzalez, Ana M.; Korioth-Schmitz, Birgit; Gelman, Rebecca S.; Montefiori, David C.; Haynes, Barton F.; Schmitz, Joern E.

    2015-01-01

    ABSTRACT To date, most therapeutic and vaccine candidates for human immunodeficiency virus type 1 (HIV-1) are evaluated preclinically for efficacy against cell-free viral challenges. However, cell-associated HIV-1 is suggested to be a major contributor to sexual transmission by mucosal routes. To determine if neutralizing antibodies or inhibitors block cell-free and cell-associated virus transmission of diverse HIV-1 strains with different efficiencies, we tested 12 different antibodies and five inhibitors against four green fluorescent protein (GFP)-labeled HIV-1 envelope (Env) variants from transmitted/founder (T/F) or chronic infection isolates. We evaluated antibody/inhibitor-mediated virus neutralization using either TZM-bl target cells, in which infectivity was determined by virus-driven luciferase expression, or A3R5 lymphoblastoid target cells, in which infectivity was evaluated by GFP expression. In both the TZM-bl and A3R5 assays, cell-free virus or infected CD4+ lymphocytes were used as targets for neutralization. We further hypothesized that the combined use of specific neutralizing antibodies targeting HIV-1 Env would more effectively prevent cell-associated virus transmission than the use of individual antibodies. The tested antibody combinations included two gp120-directed antibodies, VRC01 and PG9, or VRC01 with the gp41-directed antibody 10E8. Our results demonstrated that cell-associated virus was less sensitive to neutralizing antibodies and inhibitors, particularly using the A3R5 neutralization assay, and the potencies of these neutralizing agents differed among Env variants. A combination of different neutralizing antibodies that target specific sites on gp120 led to a significant reduction in cell-associated virus transmission. These assays will help identify ideal combinations of broadly neutralizing antibodies to use for passive preventive antibody administration and further characterize targets for the most effective neutralizing antibodies

  20. New insights into HIV-1-primary skin disorders.

    PubMed

    Cedeno-Laurent, Filiberto; Gómez-Flores, Minerva; Mendez, Nora; Ancer-Rodríguez, Jesús; Bryant, Joseph L; Gaspari, Anthony A; Trujillo, Jose R

    2011-01-24

    Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis.Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4+ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation.The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations.

  1. New insights into HIV-1-primary skin disorders

    PubMed Central

    2011-01-01

    Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis. Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4+ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation. The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations. PMID:21261982

  2. Curcumin inhibits HIV-1 by promoting Tat protein degradation

    PubMed Central

    Ali, Amjad; Banerjea, Akhil C.

    2016-01-01

    HIV-1 Tat is an intrinsically unfolded protein playing a pivotal role in viral replication by associating with TAR region of viral LTR. Unfolded proteins are degraded by 20S proteasome in an ubiquitin independent manner. Curcumin is known to activate 20S proteasome and promotes the degradation of intrinsically unfolded p53 tumor suppressor protein. Since HIV-1 Tat protein is largerly unfolded, we hypothesized that Tat may also be targeted through this pathway. Curcumin treated Tat transfected HEK-293T cells showed a dose and time dependent degradation of Tat protein. Contrary to this HIV-1 Gag which is a properly folded protein, remained unaffected with curcumin. Semi-quantitative RT-PCR analysis showed that curcumin treatment did not affect Tat gene transcription. Curcumin increased the rate of Tat protein degradation as shown by cycloheximide (CHX) chase assay. Degradation of the Tat protein is accomplished through proteasomal pathway as proteasomal inhibitor MG132 blocked Tat degradation. Curcumin also decreased Tat mediated LTR promoter transactivation and inhibited virus production from HIV-1 infected cells. Taken together our study reveals a novel observation that curcumin causes potent degradation of Tat which may be one of the major mechanisms behind its anti HIV activity. PMID:27283735

  3. Curcumin inhibits HIV-1 by promoting Tat protein degradation.

    PubMed

    Ali, Amjad; Banerjea, Akhil C

    2016-01-01

    HIV-1 Tat is an intrinsically unfolded protein playing a pivotal role in viral replication by associating with TAR region of viral LTR. Unfolded proteins are degraded by 20S proteasome in an ubiquitin independent manner. Curcumin is known to activate 20S proteasome and promotes the degradation of intrinsically unfolded p53 tumor suppressor protein. Since HIV-1 Tat protein is largerly unfolded, we hypothesized that Tat may also be targeted through this pathway. Curcumin treated Tat transfected HEK-293T cells showed a dose and time dependent degradation of Tat protein. Contrary to this HIV-1 Gag which is a properly folded protein, remained unaffected with curcumin. Semi-quantitative RT-PCR analysis showed that curcumin treatment did not affect Tat gene transcription. Curcumin increased the rate of Tat protein degradation as shown by cycloheximide (CHX) chase assay. Degradation of the Tat protein is accomplished through proteasomal pathway as proteasomal inhibitor MG132 blocked Tat degradation. Curcumin also decreased Tat mediated LTR promoter transactivation and inhibited virus production from HIV-1 infected cells. Taken together our study reveals a novel observation that curcumin causes potent degradation of Tat which may be one of the major mechanisms behind its anti HIV activity. PMID:27283735

  4. Structural Insight into HIV-1 Restriction by MxB

    PubMed Central

    Alvarez, Frances Joan D.; Summers, Brady J.; Dewdney, Tamaria G.; Aiken, Christopher; Zhang, Peijun; Engelman, Alan; Xiong, Yong

    2014-01-01

    Summary The myxovirus resistance (Mx) proteins are interferon-induced dynamin GTPases that can inhibit a variety of viruses. Recently, MxB, but not MxA, was shown to restrict HIV-1 by an unknown mechanism that likely occurs in close proximity to the host cell nucleus and involves the viral capsid. Here, we present the crystal structure of MxB and reveal determinants involved in HIV-1 restriction. MxB adopts an extended anti-parallel dimer and dimerization, but not higher-ordered oligomerization, is critical for restriction. Although MxB is structurally similar to MxA, the orientation of individual domains differs between MxA and MxB and their antiviral functions rely on separate determinants, indicating distinct mechanisms for virus inhibition. Additionally, MxB directly binds the HIV-1 capsid and this interaction depends on dimerization and the N-terminus of MxB as well as the assembled capsid lattice. These insights establish a framework for understanding the mechanism by which MxB restricts HIV-1. PMID:25312384

  5. Effects of human SAMHD1 polymorphisms on HIV-1 susceptibility

    SciTech Connect

    White, Tommy E.; Brandariz-Nuñez, Alberto; Valle-Casuso, Jose Carlos; Knowlton, Caitlin; Kim, Baek; Sawyer, Sara L.; Diaz-Griffero, Felipe

    2014-07-15

    SAMHD1 is a human restriction factor that prevents efficient infection of macrophages, dendritic cells and resting CD4+ T cells by HIV-1. Here we explored the antiviral activity and biochemical properties of human SAMHD1 polymorphisms. Our studies focused on human SAMHD1 polymorphisms that were previously identified as evolving under positive selection for rapid amino acid replacement during primate speciation. The different human SAMHD1 polymorphisms were tested for their ability to block HIV-1, HIV-2 and equine infectious anemia virus (EIAV). All studied SAMHD1 variants block HIV-1, HIV-2 and EIAV infection when compared to wild type. We found that these variants did not lose their ability to oligomerize or to bind RNA. Furthermore, all tested variants were susceptible to degradation by Vpx, and localized to the nuclear compartment. We tested the ability of human SAMHD1 polymorphisms to decrease the dNTP cellular levels. In agreement, none of the different SAMHD1 variants lost their ability to reduce cellular levels of dNTPs. Finally, we found that none of the tested human SAMHD1 polymorphisms affected the ability of the protein to block LINE-1 retrotransposition. - Highlights: • Human SAMHD1 single-nucleotide polymorphisms block HIV-1 and HIV-2 infection. • SAMHD1 polymorphisms do not affect its ability to block LINE-1 retrotransposition. • SAMHD1 polymorphisms decrease the cellular levels of dNTPs.

  6. Is the central nervous system a reservoir of HIV-1?

    PubMed Central

    Gray, Lachlan R.; Roche, Michael; Flynn, Jacqueline K.; Wesselingh, Steve L.; Gorry, Paul R.; Churchill, Melissa J.

    2014-01-01

    Purpose of the review To summarize the evidence in the literature that supports the CNS as a viral reservoir for HIV-1 and to prioritise future research efforts. Recent findings HIV-1 DNA has been detected in brain tissue of patients with undetectable viral load or neurocognitive disorders, and is associated with long-lived cells such as astrocytes and microglia. In neurocognitively normal patients, HIV-1 can be found at high frequency in these cells (4% of astrocytes and 20% of macrophages). CNS cells have unique molecular mechanisms to suppress viral replication and induce latency, which include increased expression of dominant negative transcription factors and suppressive epigenetic factors. There is also evidence of continued inflammation in patients lacking a CNS viral load, suggesting the production and activity of viral neurotoxins (for example Tat). Summary Together, these findings provide evidence that the CNS can potentially act as a viral reservoir of HIV-1. However, the majority of these studies were performed in historical cohorts (absence of cART or presence of viral load) which do not reflect modern day patients (cART-treated and undetectable viral load). Future studies will need to examine patient samples with these characteristics to conclusively determine if the CNS represents a relevant and important viral reservoir. PMID:25203642

  7. Harnessing the protective potential of HIV-1 neutralizing antibodies

    PubMed Central

    Smith, S Abigail; Derdeyn, Cynthia A

    2016-01-01

    Recent biological, structural, and technical advances are converging within the HIV-1 vaccine field to harness the power of antibodies for prevention and therapy. Numerous monoclonal antibodies with broad neutralizing activity against diverse HIV-1 isolates have now been identified, revealing at least five sites of vulnerability on the envelope (Env) glycoproteins. While there are practical and technological barriers blocking a clear path from broadly neutralizing antibodies (bNAb) to a protective vaccine, this is not a dead end. Scientists are revisiting old approaches with new technology, cutting new trails through unexplored territory, and paving new roads in the hopes of preventing HIV-1 infection. Other promising avenues to capitalize on the power of bNAbs are also being pursued, such as passive antibody immunotherapy and gene therapy approaches. Moreover, non-neutralizing antibodies have inhibitory activities that could have protective potential, alone or in combination with bNAbs. With a new generation of bNAbs, and a clinical trial that associated antibodies with reduced acquisition, the field is closer than ever to developing strategies to use antibodies against HIV-1. PMID:26918160

  8. HIV-1 Vpr—a still “enigmatic multitasker”

    PubMed Central

    Guenzel, Carolin A.; Hérate, Cécile; Benichou, Serge

    2014-01-01

    Like other HIV-1 auxiliary proteins, Vpr is conserved within all the human (HIV-1, HIV-2) and simian (SIV) immunodeficiency viruses. However, Vpr and homologous HIV-2, and SIV Vpx are the only viral auxiliary proteins specifically incorporated into virus particles through direct interaction with the Gag precursor, indicating that this presence in the core of the mature virions is mainly required for optimal establishment of the early steps of the virus life cycle in the newly infected cell. In spite of its small size, a plethora of effects and functions have been attributed to Vpr, including induction of cell cycle arrest and apoptosis, modulation of the fidelity of reverse transcription, nuclear import of viral DNA in macrophages and other non-dividing cells, and transcriptional modulation of viral and host cell genes. Even if some more recent studies identified a few cellular targets that HIV-1 Vpr may utilize in order to perform its different tasks, the real role and functions of Vpr during the course of natural infection are still enigmatic. In this review, we will summarize the main reported functions of HIV-1 Vpr and their significance in the context of the viral life cycle. PMID:24744753

  9. Differentially-Expressed Pseudogenes in HIV-1 Infection.

    PubMed

    Gupta, Aditi; Brown, C Titus; Zheng, Yong-Hui; Adami, Christoph

    2015-10-01

    Not all pseudogenes are transcriptionally silent as previously thought. Pseudogene transcripts, although not translated, contribute to the non-coding RNA pool of the cell that regulates the expression of other genes. Pseudogene transcripts can also directly compete with the parent gene transcripts for mRNA stability and other cell factors, modulating their expression levels. Tissue-specific and cancer-specific differential expression of these "functional" pseudogenes has been reported. To ascertain potential pseudogene:gene interactions in HIV-1 infection, we analyzed transcriptomes from infected and uninfected T-cells and found that 21 pseudogenes are differentially expressed in HIV-1 infection. This is interesting because parent genes of one-third of these differentially-expressed pseudogenes are implicated in HIV-1 life cycle, and parent genes of half of these pseudogenes are involved in different viral infections. Our bioinformatics analysis identifies candidate pseudogene:gene interactions that may be of significance in HIV-1 infection. Experimental validation of these interactions would establish that retroviruses exploit this newly-discovered layer of host gene expression regulation for their own benefit.

  10. Chemical crosslinking of the subunits of HIV-1 reverse transcriptase.

    PubMed Central

    Debyser, Z.; De Clercq, E.

    1996-01-01

    The reverse transcriptase (RT) of the human immunodeficiency virus type 1 (HIV-1) is composed of two subunits of 66 and 51 kDa in a 1 to 1 ratio. Because dimerization is a prerequisite for enzymatic activity, interference with the dimerization process could constitute an alternative antiviral strategy for RT inhibition. Here we describe an in vitro assay for the study of the dimerization state of HIV-1 reverse transcriptase based on chemical crosslinking of the subunits with dimethylsuberimidate. Crosslinking results in the formation of covalent bonds between the subunits, so that the crosslinked species can be resolved by denaturing gel electrophoresis. Crosslinked RT species with molecular weight greater than that of the dimeric form accumulate during a 1-15-min time course. Initial evidence suggests that those high molecular weight species represent trimers and tetramers and may be the result of intramolecular crosslinking of the subunits of a higher-order RT oligomer. A peptide that corresponds to part of the tryptophan repeat motif in the connection domain of HIV-1 RT inhibits crosslink formation as well as enzymatic activity. The crosslinking assay thus allows the investigation of the effect of inhibitors on the dimerization of HIV-1 RT. PMID:8745406

  11. HIV-1 Drug Resistance Mutations: Potential Applications for Point-of-Care Genotypic Resistance Testing

    PubMed Central

    Rhee, Soo-Yon; Jordan, Michael R.; Raizes, Elliot; Chua, Arlene; Parkin, Neil; Kantor, Rami; Van Zyl, Gert U.; Mukui, Irene; Hosseinipour, Mina C.; Frenkel, Lisa M.; Ndembi, Nicaise; Hamers, Raph L.; Rinke de Wit, Tobias F.; Wallis, Carole L.; Gupta, Ravindra K.; Fokam, Joseph; Zeh, Clement; Schapiro, Jonathan M.; Carmona, Sergio; Katzenstein, David; Tang, Michele; Aghokeng, Avelin F.; De Oliveira, Tulio; Wensing, Annemarie M. J.; Gallant, Joel E.; Wainberg, Mark A.; Richman, Douglas D.; Fitzgibbon, Joseph E.; Schito, Marco; Bertagnolio, Silvia; Yang, Chunfu; Shafer, Robert W.

    2015-01-01

    The increasing prevalence of acquired and transmitted HIV-1 drug resistance is an obstacle to successful antiretroviral therapy (ART) in the low- and middle-income countries (LMICs) hardest hit by the HIV-1 pandemic. Genotypic drug resistance testing could facilitate the choice of initial ART in areas with rising transmitted drug resistance (TDR) and enable care-providers to determine which individuals with virological failure (VF) on a first- or second-line ART regimen require a change in treatment. An inexpensive near point-of-care (POC) genotypic resistance test would be useful in settings where the resources, capacity, and infrastructure to perform standard genotypic drug resistance testing are limited. Such a test would be particularly useful in conjunction with the POC HIV-1 viral load tests that are currently being introduced in LMICs. A POC genotypic resistance test is likely to involve the use of allele-specific point mutation assays for detecting drug-resistance mutations (DRMs). This study proposes that two major nucleoside reverse transcriptase inhibitor (NRTI)-associated DRMs (M184V and K65R) and four major NNRTI-associated DRMs (K103N, Y181C, G190A, and V106M) would be the most useful for POC genotypic resistance testing in LMIC settings. One or more of these six DRMs was present in 61.2% of analyzed virus sequences from ART-naïve individuals with intermediate or high-level TDR and 98.8% of analyzed virus sequences from individuals on a first-line NRTI/NNRTI-containing regimen with intermediate or high-level acquired drug resistance. The detection of one or more of these DRMs in an ART-naïve individual or in a individual with VF on a first-line NRTI/NNRTI-containing regimen may be considered an indication for a protease inhibitor (PI)-containing regimen or closer virological monitoring based on cost-effectiveness or country policy. PMID:26717411

  12. HIV-1 Drug Resistance Mutations: Potential Applications for Point-of-Care Genotypic Resistance Testing.

    PubMed

    Rhee, Soo-Yon; Jordan, Michael R; Raizes, Elliot; Chua, Arlene; Parkin, Neil; Kantor, Rami; Van Zyl, Gert U; Mukui, Irene; Hosseinipour, Mina C; Frenkel, Lisa M; Ndembi, Nicaise; Hamers, Raph L; Rinke de Wit, Tobias F; Wallis, Carole L; Gupta, Ravindra K; Fokam, Joseph; Zeh, Clement; Schapiro, Jonathan M; Carmona, Sergio; Katzenstein, David; Tang, Michele; Aghokeng, Avelin F; De Oliveira, Tulio; Wensing, Annemarie M J; Gallant, Joel E; Wainberg, Mark A; Richman, Douglas D; Fitzgibbon, Joseph E; Schito, Marco; Bertagnolio, Silvia; Yang, Chunfu; Shafer, Robert W

    2015-01-01

    The increasing prevalence of acquired and transmitted HIV-1 drug resistance is an obstacle to successful antiretroviral therapy (ART) in the low- and middle-income countries (LMICs) hardest hit by the HIV-1 pandemic. Genotypic drug resistance testing could facilitate the choice of initial ART in areas with rising transmitted drug resistance (TDR) and enable care-providers to determine which individuals with virological failure (VF) on a first- or second-line ART regimen require a change in treatment. An inexpensive near point-of-care (POC) genotypic resistance test would be useful in settings where the resources, capacity, and infrastructure to perform standard genotypic drug resistance testing are limited. Such a test would be particularly useful in conjunction with the POC HIV-1 viral load tests that are currently being introduced in LMICs. A POC genotypic resistance test is likely to involve the use of allele-specific point mutation assays for detecting drug-resistance mutations (DRMs). This study proposes that two major nucleoside reverse transcriptase inhibitor (NRTI)-associated DRMs (M184V and K65R) and four major NNRTI-associated DRMs (K103N, Y181C, G190A, and V106M) would be the most useful for POC genotypic resistance testing in LMIC settings. One or more of these six DRMs was present in 61.2% of analyzed virus sequences from ART-naïve individuals with intermediate or high-level TDR and 98.8% of analyzed virus sequences from individuals on a first-line NRTI/NNRTI-containing regimen with intermediate or high-level acquired drug resistance. The detection of one or more of these DRMs in an ART-naïve individual or in a individual with VF on a first-line NRTI/NNRTI-containing regimen may be considered an indication for a protease inhibitor (PI)-containing regimen or closer virological monitoring based on cost-effectiveness or country policy. PMID:26717411

  13. High levels of CC-chemokine expression and downregulated levels of CCR5 during HIV-1/HTLV-1 and HIV-1/HTLV-2 coinfections.

    PubMed

    Oo, Z; Barrios, C S; Castillo, L; Beilke, M A

    2015-05-01

    The human T-cell lymphotropic virus type 1 (HTLV-1) and HTLV-2 are common copathogens among Human Immunodeficiency Virus (HIV)-infected individuals. HTLV-2 may confer a survival benefit among patients with HIV-1/HTLV-2 coinfections, along with lower plasma HIV-1 levels and delayed rates of CD4(+) T-cell decline. These effects have been attributed to the ability of the HTLV-2 viral transactivating Tax2 protein to induce the production of high levels of antiviral CC-chemokines and to downregulate expression of the CCR5 receptor, resulting in impaired entry of HIV-1 into CD4(+) T-cells. This study investigated the innate immunity of coinfected HIV/HTLV individuals by testing the ability of patient PBMCs to produce CC-chemokines in association CCR5 receptor modulation. The cellular proliferative responses of HIV/HTLV coinfected versus HIV monoinfected individuals were also evaluated. Higher levels of MIP-1α, MIP-1β, and RANTES (P < 0.05) were found in HIV-1/HTLV-2 coinfected group compared to HIV-1 monoinfected population. Upregulated levels of RANTES were shown in HIV-1/HTLV-1 after 1 and 3 days of culture (P < 0.05). Lymphocytes from HIV-1/HTLV-2 coinfected individuals showed significant CCR5 downregulation after 1 and 3 days of culture compared to lymphocytes from HIV-1 and uninfected groups (P < 0.05). Lower percentages of CCR5-positive cells were found in HIV-1/HTLV-1 coinfected after 3 days of incubation (P < 0.05). Levels of proliferation were significantly higher in the HIV-1/HTLV-1 group compared to HIV-1 alone (P < 0.05). HTLV-2 and HTLV-1 infections may induce the involvement of innate immunity against HIV-1 via stimulation of CC-chemokines and receptors, potentially modifying CCR5/HIV-1 binding and HIV-1 progression in coinfected individuals.

  14. Wide distribution of two subtypes of HIV-1 in Thailand.

    PubMed

    Ou, C Y; Takebe, Y; Luo, C C; Kalish, M; Auwanit, W; Bandea, C; de la Torre, N; Moore, J L; Schochetman, G; Yamazaki, S

    1992-08-01

    Scientists wanted to identify the genetic characteristics of 2 HIV-1 subtypes in Thailand. Staff from regional laboratories of the Ministry of Public Health took blood samples from people in various high risk groups and from all regions of the country. Staff at the National Institutes of Health in Bangkok then did lymphocyte separation, DNA extraction, and virus culture. They took the extracted DNA specimens and sent them to the US Centers for Disease Control where scientists did serologic testing, polymerase chain reaction, and sequence determination. They used Kimura's method to study sequence variations. They sequenced 300 nucleotides, including the C2-V3 domains of HIV-1 envelope gene and/or hybridization. Every risk group had HIV-1 subtype A, but subtype B was mostly found in drug users. Subtype A had spread mainly among heterosexuals. The mean intraperson variation for subtypes A and B stood at 2% and 2.7%, respectively, while the interperson variation within subtype A and B stood at 3.8% and 3.7%, respectively. The mean interperson variation between subtypes A and B from different persons was 18.1%. Phylogenetic tree analysis showed that subtype B identified with about 85% of the sequence as that of the North American isolates, making it more closely related to them than to African isolates (about 75% sequence identity). On the other hand, subtype A had a GPGQ motif at the V3 crown which was common among African HIV-1 isolates. Antibodies which usually recognize HIV-1 MN strains (which have the GPGR motif) may not react wholly with the V3 loop from the Thailand subtype A viruses, thus the GPGQ motif at the V3 crown may pose a problem. Now for the first time, scientists can follow the natural history of 2 HIV-1 subtypes and determine their relative pathogenicity and transmission efficiency between adults or from mother to infant. The relative homogeneity of the HIV-1 strains in Thailand presents a theoretical advantage in designing vaccines for potential

  15. Sub-Epidemics Explain Localized High Prevalence of Reduced Susceptibility to Rilpivirine in Treatment-Naive HIV-1-Infected Patients: Subtype and Geographic Compartmentalization of Baseline Resistance Mutations

    PubMed Central

    Van Laethem, Kristel; Gomes, Perpetua; Baele, Guy; Pineda-Peña, Andrea-Clemencia; Vandamme, Anne-Mieke; Camacho, Ricardo J.; Abecasis, Ana B.

    2016-01-01

    Abstract Objective: The latest nonnucleoside reverse transcriptase inhibitor (NNRTI) rilpivirine (RPV) is indicated for human immunodeficiency virus type-1 (HIV-1) patients initiating antiretroviral treatment, but the extent of genotypic RPV resistance in treatment-naive patients outside clinical trials is poorly defined. Study Design: This retrospective observational study of clinical data from Belgium and Portugal evaluates genotypic information from HIV-1 drug-naive patients obtained for the purpose of drug resistance testing. Rilpivirine resistance-associated mutations (RPV-RAMs) were defined based on clinical trials, phenotypic studies, and expert-based resistance algorithms. Viral susceptibility to RPV alone and to the single-tablet regimen was estimated using expert-based resistance algorithms. Results: In 4,631 HIV-1 treatment-naive patients infected with diverse HIV-1 subtypes, major RPV-RAMs were detected in 4.6%, while complete viral susceptibility to RPV was estimated in 95% of patients. Subtype C- and F1-infected patients displayed the highest levels of reduced viral susceptibility at baseline, respectively 13.2% and 9.3%, mainly due to subtype- and geographic-dependent occurrence of RPV-RAMs E138A and A98G as natural polymorphisms. Strikingly, a founder effect in Portugal resulted in a 138A prevalence of 13.2% in local subtype C-infected treatment-naive patients. The presence of transmitted drug resistance did not impact our estimates. Conclusion: RPV is the first HIV-1 inhibitor for which, in the absence of transmitted drug resistance, intermediate or high-level genotypic resistance can be detected in treatment-naive patients. The extent of RPV susceptibility in treatment-naive patients differs depending on the HIV-1 subtype and dynamics of local compartmentalized epidemics. The highest prevalence of reduced susceptibility was found to be 15.7% in Portuguese subtype C-infected treatment-naive patients. In this context, even in the absence of

  16. Inhibition of HIV-1 Tat-mediated LTR transactivation and HIV-1 infection by anti-Tat single chain intrabodies.

    PubMed Central

    Mhashilkar, A M; Bagley, J; Chen, S Y; Szilvay, A M; Helland, D G; Marasco, W A

    1995-01-01

    Genes encoding the rearranged immunoglobulin heavy and light chain variable regions of anti-HIV-1 Tat, exon 1 or exon 2 specific monoclonal antibodies have been used to construct single chain intracellular antibodies 'intrabodies' for expression in the cytoplasm of mammalian cells. These anti-Tat single chain intrabodies (anti-Tat sFvs) are additionally modified with a C-terminal human C kappa domain to increase cytoplasmic stability and/or the C-terminal SV40 nuclear localization signal to direct the nascent intrabody to the nuclear compartment, respectively. The anti-Tat sFvs with specific binding activity against the N-terminal activation domain of Tat, block Tat-mediated transactivation of HIV-1 LTR as well as intracellular trafficking of Tat in mammalian cells. As a result, the transformed lymphocytes expressing anti-Tat sFvs are resistant to HIV-1 infection. Thus, these studies demonstrate that stably expressed single chain intrabodies and their modified forms can effectively target molecules in the cytoplasm and nuclear compartments of eukaryotic cells. Furthermore, these studies suggest that anti-Tat sFvs used either alone or in combination with other genetically based strategies may be useful for the gene therapy of HIV-1 infection and AIDS. Images PMID:7537216

  17. Performance of rapid tests for discrimination between HIV-1 and/or HIV-2 infections.

    PubMed

    Gautheret-Dejean, Agnès; Bocobza, Jonathan; Brunet, Sylvie; Damond, Florence; Plantier, Jean-Christophe; Barin, Francis

    2015-12-01

    Major differences exist between HIV-1 and HIV-2 in terms of epidemiology, pathogenicity, sensitivity to antiretrovirals. Determining the type of HIV infecting a patient is essential for management. The aim of this study was to evaluate the ability of simple/rapid tests to differentiate between HIV-1 and/or HIV-2 infections. We analyzed 116 samples from patients infected with HIV-1 (n = 61), HIV-2 (n = 47), or HIV-1+HIV-2 (n = 8) at the chronic stage of infection. Each sample was tested with SD Bioline HIV-1/2 3.0, ImmunoFlow HIV1-HIV2, ImmunoFlow HIV1-HIV2 (WB), Genie III HIV-1/HIV-2, ImmunoComb HIV1&2 BiSpot. HIV-1, or HIV-2 single infection was identified with a sensitivity ranging from 90% to 100%. The ability to detect dual infection was less sensitive (12.5-100%). SD Bioline HIV-1/2 3.0, ImmunoFlow HIV1-HIV2, and Genie III were unable to detect HIV-1 group O infection in one, one and two cases, respectively. The specificity of detection of HIV-1, HIV-2, or HIV-1+HIV-2 antibodies differed greatly (36-100%). ImmunoComb BiSpot had the highest sensitivity values (99-100% for HIV-1, 98% for HIV-2, and 75-87.5% for dual infection) and specificity values (94-100% for HIV-1, 100% for HIV-2, and 97-100% for dual infection). In conclusion, this study showed that no single rapid test had a perfect sensitivity/specificity ratio, particularly in the case of the double infections.

  18. German-austrian recommendations for HIV1-therapy in pregnancy and in HIV1-exposed newborn - update 2008

    PubMed Central

    2009-01-01

    German-Austrian recommendations for HIV1-therapy in pregnancy - Update 2008 Bernd Buchholz (University Medical Centre Mannheim, Pediatric Clinic), Matthias Beichert (Mannheim, Gynecology and Obstetrics Practice), Ulrich Marcus (Robert Koch Institute, Berlin), Thomas Grubert, Andrea Gingelmaier (Gynecology Clinic of the Ludwig Maximilians University of Munich), Dr. med. Annette Haberl (HIV-Department, J. W. Goethe-University Hospital, Frankfurt), Dr. med. Brigitte Schmied (Otto-Wagner Spital, Wien). In Germany during the last years about 200-250 HIV1-infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV1-infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV1 was reduced to 1-2%. This low transmission rate has been achieved by the combination of anti-retroviral therapy of pregnant women, caesarean section scheduled before onset of labour, anti-retroviral post exposition prophylaxis in the newborn and refraining from breast-feeding by the HIV1-infected mother. To keep pace with new results in research, approval of new anti-retroviral drugs and changes in the general treatment recommendations for HIV1-infected adults, in 1998, 2001, 2003 and 2005 an interdisciplinary consensus meeting was held. Gynaecologists, infectious disease specialists, paediatricians, pharmacologists, virologists and members of the German AIDS Hilfe (NGO) were participating in this conference to update the prevention strategies. A fifth update became necessary in 2008. The updating process was started in January 2008 and was terminated in September 2008. The guidelines provide new recommendations on the indication and the starting point for HIV-therapy in pregnancies without complications, drugs and drug combinations to be used preferably in these

  19. Enhancing Interferon Regulatory Factor 7 Mediated Antiviral Responses and Decreasing Nuclear Factor Kappa B Expression Limit HIV-1 Replication in Cervical Tissues

    PubMed Central

    Rollenhage, Christiane; Macura, Sherrill L.; Lathrop, Melissa J.; Mackenzie, Todd A.; Doncel, Gustavo F.; Asin, Susana N.

    2015-01-01

    harnessed to develop preventative combination strategies to improve the efficacy of topical or systemic antiviral prophylactic agents and protect women from HIV-1 and other sexually transmitted infections. PMID:26121689

  20. A novel RealTime HIV-1 Qualitative assay for the detection of HIV-1 nucleic acids in dried blood spots and plasma.

    PubMed

    Huang, Shihai; Erickson, Brian; Mak, Wai Bing; Salituro, John; Abravaya, Klara

    2011-12-01

    Abbott RealTime HIV-1 Qualitative is an in vitro real-time PCR assay for detecting HIV-1 nucleic acids in human plasma and dried blood spots (DBS). The assay was designed to be used in diagnosis of HIV-1 infections in pediatric and adult patients, with an emphasis on the applicability in resource-limited settings. Use of DBS facilitates specimen collection from remote areas and transportation to testing laboratories. Small sample input requirement facilitates testing of specimens with limited collection volume. The Abbott RealTime HIV-1 Qualitative assay is capable of detecting HIV-1 group M subtypes A-H, group O and group N samples. HIV-1 virus concentrations detected with 95% probability were 80 copies/mL of plasma using the plasma protocol, and 2469 copies/mL of whole blood using the DBS protocol. The assay detected HIV-1 infection in 13 seroconversion panels an average 10.5 days earlier than an HIV-1 antibody test and 4.9 days earlier than a p24 antigen test. For specimens collected from 6 weeks to 18 months old infants born to HIV-1 positive mothers, assay results using both the DBS and plasma protocols agreed well with the Roche Amplicor HIV-1 DNA Test version 1.5 (95.5% agreement for DBS and 97.8% agreement for plasma).

  1. Human Immunodeficiency Virus Type 1 (HIV-1) Vpr Functions as an Immediate-Early Protein during HIV-1 Infection

    PubMed Central

    Hrimech, Mohammed; Yao, Xiao-Jian; Bachand, François; Rougeau, Nicole; Cohen, Éric A.

    1999-01-01

    Human immunodeficiency virus type 1 (HIV-1) Vpr is a virion-associated protein which facilitates HIV-1 infection of nondividing cells by contributing to the nuclear transport of the preintegration complex (PIC). Vpr was also shown to induce a cell cycle G2 arrest in infected proliferating cells that optimizes HIV-1 long terminal repeat (LTR)-directed gene expression and viral production. However, it is unclear whether this activity is mediated primarily early by virion-associated Vpr or alternatively late during infection when Vpr is de novo expressed. We report here that in the absence of de novo expression, virion-associated Vpr induces a transient G2 arrest that can subsequently lead to cell killing by apoptosis. Interestingly, the induction of both cell cycle G2 arrest and apoptosis by virion-associated Vpr requires viral entry but not viral replication, since reverse transcriptase and protease inhibitor treatments do not prevent these Vpr effects. These results raise the possibility that in vivo both infectious and noninfectious viruses contribute to the dysfunction and killing of CD4+ cells. In addition, our results reveal that virion-associated Vpr stimulates viral replication in proliferating cells after establishing a cell cycle G2 arrest by increasing LTR-directed gene expression. Importantly, this Vpr-mediated LTR activation appears to be a requirement for subsequent optimal Tat transactivation. Taken together, these results strongly suggest that in addition to participating in the HIV PIC nuclear transport in nondividing cells, virion-associated Vpr activates HIV-1 LTR-directed gene expression by manipulating the host cell cycle. From this, we conclude that Vpr functions as an immediate-early protein during HIV-1 infection. PMID:10196306

  2. HIV-1 vaccine development: constrained peptide immunogens show improved binding to the anti-HIV-1 gp41 MAb.

    PubMed

    McGaughey, G B; Citron, M; Danzeisen, R C; Freidinger, R M; Garsky, V M; Hurni, W M; Joyce, J G; Liang, X; Miller, M; Shiver, J; Bogusky, M J

    2003-03-25

    The human immunodeficiency virus type I (HIV-1) transmembrane glycoprotein gp41 mediates viral entry through fusion of the target cellular and viral membranes. A segment of gp41 containing the sequence Glu-Leu-Asp-Lys-Trp-Ala has previously been identified as the epitope of the HIV-1 neutralizing human monoclonal antibody 2F5 (MAb 2F5). The 2F5 epitope is highly conserved among HIV-1 envelope glycoproteins. Antibodies directed at the 2F5 epitope have neutralizing effects on a broad range of laboratory-adapted HIV-1 variants and primary isolates. Recently, a crystal structure of the epitope bound to the Fab fragment of MAb 2F5 has shown that the 2F5 peptide adopts a beta-turn conformation [Pai, E. F., Klein, M. H., Chong, P., and Pedyczak, A. (2000) World Intellectual Property Organization Patent WO-00/61618]. We have designed cyclic peptides to adopt beta-turn conformations by the incorporation of a side-chain to side-chain lactam bridge between the i and i + 4 residues containing the Asp-Lys-Trp segment. Synthesis of extended, nonconstrained peptides encompassing the 2F5 epitope revealed that the 13 amino acid sequence, Glu-Leu-Leu-Glu-Leu-Asp-Lys-Trp-Ala-Ser-Leu-Trp-Asn, maximized MAb 2F5 binding. Constrained analogues of this sequence were explored to optimize 2F5 binding affinity. The solution conformations of the constrained peptides have been characterized by NMR spectroscopy and molecular modeling techniques. The results presented here demonstrate that both inclusion of the lactam constraint and extension of the 2F5 segment are necessary to elicit optimal antibody binding activity. The ability of these peptide immunogens to stimulate a high titer, peptide-specific immune response incapable of viral neutralization is discussed in regard to developing an HIV-1 vaccine designed to elicit a 2F5-like immune response. PMID:12641452

  3. HIV-1 Induced Nuclear Factor I-B (NF-IB) Expression Negatively Regulates HIV-1 Replication through Interaction with the Long Terminal Repeat Region

    PubMed Central

    Vemula, Sai Vikram; Veerasamy, Ravichandran; Ragupathy, Viswanath; Biswas, Santanu; Devadas, Krishnakumar; Hewlett, Indira

    2015-01-01

    Background: Retroviruses rely on host factors for cell entry, replication, transcription, and other major steps during their life cycle. Human Immunodeficiency Virus-1 (HIV-1) is well known for utilizing a plethora of strategies to evade the host immune response, including the establishment of latent infection within a subpopulation of susceptible cells. HIV-1 also manipulates cellular factors in latently infected cells and persists for long periods of time, despite the presence of successful highly active antiretroviral therapy (HAART). Results: In this study we demonstrate that Nuclear Factor-IB (NF-IB) is induced during HIV-1 infection and its expression negatively impacts viral replication. During HIV-1 infection in peripheral blood mononuclear cells (PBMCs), and the T cell line, Jurkat or during induction of virus replication in latently infected cells, ACH2 and J1.1, we observed a time-dependent alteration in NF-IB expression pattern that correlated with HIV-1 viral expression. Using the Chip assay, we observed an association of NF-IB with the long terminal repeat region of HIV-1 (LTR) (-386 to -453 nt), and this association negatively correlated with HIV-1 transcription. Furthermore, knock-down of NF-IB levels in J1.1 cells resulted in an increase of HIV-1 levels. Knock-down of NF-IB levels in J-Lat-Tat-GFP (A1), (a Jurkat cell GFP reporter model for latent HIV-1 infection) resulted in an increase in GFP levels, indicating a potential negative regulatory role of NF-IB in HIV-1 replication. Conclusion: Overall, our results suggest that NF-IB may play a role in intrinsic antiretroviral defenses against HIV-1. These observations may offer new insights into the correlation of the latently infected host cell types and HIV-1, and help to define new therapeutic approaches for triggering the switch from latency to active replication thereby eliminating HIV-1 latent infection. PMID:25664610

  4. Low dose rectal inoculation of rhesus macaques by SIV SME660 or SIV MAC251 recapitulates human mucosal infection by HIV-1

    SciTech Connect

    Koraber, Bette; Perelson, Alan; Hraber, Peter; Giorgi, E; Bhattacharya, T

    2009-01-01

    Recently, we developed a novel approach to the identification of transmitted or early founder HIV -1 genomes in acutely infected humans based on single genome amplification and sequencing. Here we tested this approach in 18 acutely infected Indian rhesus macaques to determine the molecular features of SIV transmission. Animals were inoculated intrarectally (IR) or intravenously (IV) with stocks of SIVmac251 or SIVsmE660 that exhibited sequence diversity typical of early-chronic HIV -1 infection. 987 full-length SIV env sequences (median of 48 per animal) were determined from plasma virion RNA one to five weeks after infection. IR inoculation was followed by productive infection by one or few viruses (median 1; range 1-5) that diversified randomly with near star-like phylogeny and a Poisson distribution of mutations. Consensus viral sequences from ramp-up and peak viremia were identical to viruses found in the inocula or differed from them by only one or few nuc1eotides, providing direct evidence that early plasma viral sequences coalesce to transmitted/founder virus( es). IV infection was approximately 10,000-fold more efficient than IR infection, and viruses transmitted by either route represented the full genetic spectra of the inocula. These findings identify key similarities in mucosal transmission and early diversification between SIV and HIV -1.

  5. Mosaic clade M human immunodeficiency virus type 1 (HIV-1) envelope immunogens

    DOEpatents

    Korber, Bette T.; Fischer, William; Liao, Hua-Xin; Haynes, Barton F.; Letvin, Norman; Hahn; Beatrice H.

    2011-05-31

    The present invention relates to mosaic clade M HIV-1 Env polypeptides and to compositions comprising same. The polypeptides of the invention are suitable for use in inducing an immune response to HIV-1 in a human.

  6. Abrogation of contaminating RNA activity in HIV-1 Gag VLPs

    PubMed Central

    2011-01-01

    Background HIV-1 Gag virus like particles (VLPs) used as candidate vaccines are regarded as inert particles as they contain no replicative nucleic acid, although they do encapsidate cellular RNAs. During HIV-1 Gag VLP production in baculovirus-based expression systems, VLPs incorporate the baculovirus Gp64 envelope glycoprotein, which facilitates their entry into mammalian cells. This suggests that HIV-1 Gag VLPs produced using this system facilitate uptake and subsequent expression of encapsidated RNA in mammalian cells - an unfavourable characteristic for a vaccine. Methods HIV-1 Gag VLPs encapsidating reporter chloramphenicol acetyl transferase (CAT) RNA, were made in insect cells using the baculovirus expression system. The presence of Gp64 on the VLPs was verified by western blotting and RT-PCR used to detect and quantitate encapsidated CAT RNA. VLP samples were heated to inactivate CAT RNA. Unheated and heated VLPs incubated with selected mammalian cell lines and cell lysates tested for the presence of CAT protein by ELISA. Mice were inoculated with heated and unheated VLPs using a DNA prime VLP boost regimen. Results HIV-1 Gag VLPs produced had significantly high levels of Gp64 (~1650 Gp64 molecules/VLP) on their surfaces. The amount of encapsidated CAT RNA/μg Gag VLPs ranged between 0.1 to 7 ng. CAT protein was detected in 3 of the 4 mammalian cell lines incubated with VLPs. Incubation with heated VLPs resulted in BHK-21 and HeLa cell lysates showing reduced CAT protein levels compared with unheated VLPs and HEK-293 cells. Mice inoculated with a DNA prime VLP boost regimen developed Gag CD8 and CD4 T cell responses to GagCAT VLPs which also boosted a primary DNA response. Heating VLPs did not abrogate these immune responses but enhanced the Gag CD4 T cell responses by two-fold. Conclusions Baculovirus-produced HIV-1 Gag VLPs encapsidating CAT RNA were taken up by selected mammalian cell lines. The presence of CAT protein indicates that encapsidated RNA was

  7. Neutralization of diverse HIV-1 strains by monoclonal antibodies raised against a gp41 synthetic peptide.

    PubMed

    Dalgleish, A G; Chanh, T C; Kennedy, R C; Kanda, P; Clapham, P R; Weiss, R A

    1988-07-01

    Three IgM monoclonal antibodies raised against synthetic peptide analogs of a hydrophilic region of the gp41 transmembrane env protein of HIV-1 neutralize different HIV-1 isolates but not HIV-2 isolates, as determined by HIV titration and by syncytial inhibition assays. VSV (HIV-1) pseudotypes, however, were not neutralized, indicating that gp41 was not accessible to these antibodies on the pseudotype particles. The antibodies affect early steps in adsorption and penetration of HIV-1.

  8. Different Pathogenesis of CCR5-Using Primary HIV-1 Isolates from Non-Switch and Switch Virus Patients in Human Lymphoid Tissue Ex Vivo

    NASA Technical Reports Server (NTRS)

    Iarlsson, Ingrid; Grivel, Jean-Charles; Chen. Silvia; Karlsson, Anders; Albert, Jan; Fenyol, Eva Maria; Margolis, Leonid B.

    2005-01-01

    CCR5-utilizing HIV-1 variants (R5) typically transmit infection and dominate its early stages, whereas emergence of CXCR4-using (X4 or R5X4) HIV-1 is often associated with disease progression. However, such a switch in co-receptor usage can only be detected in approximately onehalf of HIV-infected patients (switch virus patients), and progression to immunodeficiency may also occur in patients without detectable switch in co-receptor usage (non-switch virus patients). Here, we used a system of ex vivo-infected tonsillar tissue to compare the pathogenesis of sequential primary R5 HIV-1 isolates from the switch and non-switch patients. Inoculation of ex vivo tissue with these R5 isolates resulted in viral replication and CCR5(+)CD4(+) T cell depletion. The levels of such depletion by HIV-1 isolated from non-switch virus patients were significantly higher than those by R5 HIV-1 isolates from switch virus patients. T cell depletion seemed to be controlled by viral factors and did not significantly vary between tissues from different donors. In contrast, viral replication did not correlate with the switch status of the patients; in tissues fiom different donors it varied 30-fold and seemed to be controlled by a combination of viral and tissue factors. Nevertheless, replication-level hierarchy among sequential isolates remained constant in tissues from various donors. Viral load in vivo was higher in switch virus patients compared to non-switch virus patients. The high cytopathogenicity of CCR5(+)CD4(+) T cells by R5 HIV-1 isolates from non-switch virus patients may explain the steady decline of CD4(+) T cells in the absence of CXCR4 using virus; elimination of target cells by these isolates may limit their own replication in vivo.

  9. Impact and Process Evaluation of Integrated Community and Clinic-Based HIV-1 Control: A Cluster-Randomised Trial in Eastern Zimbabwe

    PubMed Central

    Gregson, Simon; Adamson, Saina; Papaya, Spiwe; Mundondo, Jephias; Nyamukapa, Constance A; Mason, Peter R; Garnett, Geoffrey P; Chandiwana, Stephen K; Foster, Geoff; Anderson, Roy M

    2007-01-01

    Background HIV-1 control in sub-Saharan Africa requires cost-effective and sustainable programmes that promote behaviour change and reduce cofactor sexually transmitted infections (STIs) at the population and individual levels. Methods and Findings We measured the feasibility of community-based peer education, free condom distribution, income-generating projects, and clinic-based STI treatment and counselling services and evaluated their impact on the incidence of HIV-1 measured over a 3-y period in a cluster-randomised controlled trial in eastern Zimbabwe. Analysis of primary outcomes was on an intention-to-treat basis. The income-generating projects proved impossible to implement in the prevailing economic climate. Despite greater programme activity and knowledge in the intervention communities, the incidence rate ratio of HIV-1 was 1.27 (95% confidence interval [CI] 0.92–1.75) compared to the control communities. No evidence was found for reduced incidence of self-reported STI symptoms or high-risk sexual behaviour in the intervention communities. Males who attended programme meetings had lower HIV-1 incidence (incidence rate ratio 0.48, 95% CI 0.24–0.98), and fewer men who attended programme meetings reported unprotected sex with casual partners (odds ratio 0.45, 95% CI 0.28–0.75). More male STI patients in the intervention communities reported cessation of symptoms (odds ratio 2.49, 95% CI 1.21–5.12). Conclusions Integrated peer education, condom distribution, and syndromic STI management did not reduce population-level HIV-1 incidence in a declining epidemic, despite reducing HIV-1 incidence in the immediate male target group. Our results highlight the need to assess the community-level impact of interventions that are effective amongst targeted population sub-groups. PMID:17388666

  10. Compartmentalized replication of R5 T cell-tropic HIV-1 in the central nervous system early in the course of infection.

    PubMed

    Sturdevant, Christa Buckheit; Joseph, Sarah B; Schnell, Gretja; Price, Richard W; Swanstrom, Ronald; Spudich, Serena

    2015-03-01

    Compartmentalized HIV-1 replication within the central nervous system (CNS) likely provides a foundation for neurocognitive impairment and a potentially important tissue reservoir. The timing of emergence and character of this local CNS replication has not been defined in a population of subjects. We examined the frequency of elevated cerebrospinal fluid (CSF) HIV-1 RNA concentration, the nature of CSF viral populations compared to the blood, and the presence of a cellular inflammatory response (with the potential to bring infected cells into the CNS) using paired CSF and blood samples obtained over the first two years of infection from 72 ART-naïve subjects. Using single genome amplification (SGA) and phylodynamics analysis of full-length env sequences, we compared CSF and blood viral populations in 33 of the 72 subjects. Independent HIV-1 replication in the CNS (compartmentalization) was detected in 20% of sample pairs analyzed by SGA, or 7% of all sample pairs, and was exclusively observed after four months of infection. In subjects with longitudinal sampling, 30% showed evidence of CNS viral replication or pleocytosis/inflammation in at least one time point, and in approximately 16% of subjects we observed evolving CSF/CNS compartmentalized viral replication and/or a marked CSF inflammatory response at multiple time points suggesting an ongoing or recurrent impact of the infection in the CNS. Two subjects had one of two transmitted lineages (or their recombinant) largely sequestered within the CNS shortly after transmission, indicating an additional mechanism for establishing early CNS replication. Transmitted variants were R5 T cell-tropic. Overall, examination of the relationships between CSF viral populations, blood and CSF HIV-1 RNA concentrations, and inflammatory responses suggested four distinct states of viral population dynamics, with associated mechanisms of local viral replication and the early influx of virus into the CNS. This study considerably

  11. siRNA-based topical microbicides targeting sexually transmitted infections.

    PubMed

    Katakowski, Joseph A; Palliser, Deborah

    2010-04-01

    Sexually transmitted infections (STIs) are a major cause of morbidity and mortality worldwide. Although a vaccine is available for HPV, no effective vaccines exist for the HIV-1 and HSV-2 viral pathogens, and there are no cures for these infections. Furthermore, recent setbacks in clinical trials, such as the failure of the STEP trial to prevent HIV-1 infection, have emphasized the need to develop alternative approaches to interrupt the transmission of these pathogens. One alternative strategy is represented by the use of topically applied microbicides, and such agents are being developed against various viruses. RNAi-based microbicides have recently been demonstrated to prevent HSV-2 transmission, and may be useful for targeting multiple STIs. In this review, microbicides that are under development for the prevention of STIs are described, with a focus on topically applied microbicidal siRNAs.

  12. Quantitation of HIV-1 RNA in breast milk by real time PCR.

    PubMed

    Becquart, Pierre; Foulongne, Vincent; Willumsen, Juana; Rouzioux, Christine; Segondy, Michel; Van de Perre, Philippe

    2006-04-01

    HIV-1 RNA in breast milk is a strong predictor of HIV-1 transmission through breastfeeding. In the present report, breast milk samples from HIV-1 uninfected donors were spiked with dilution of quantified culture supernatant from HIV-1(NDK) infected PBMC. Two RNA extraction techniques based on silica extraction, Nuclisens (BioMerieux) and Triazol (Qiagen), two techniques based on guanidine thiocynanate/chloroforme extraction, TRIzol (Life Technologie) and Amplicor HIV-1 Monitor (Roche Diagnostic Systems), and one technique based on electrostatic adsorption on iron oxide micro beads (Promega) were compared. HIV-1 RNA was quantitated by real time PCR (LTR gene) and Amplicor HIV-1 Monitor. Combining magnetic micro beads extraction and real time PCR quantitation allowed to correctly quantify breast milk HIV-1 RNA, with a difference between the expected and measured HIV-1 RNA levels always lower than 0.3 log copies/ml. The same combination was confirmed on 25 breast milk samples from HIV-1 infected women collected in Kwazulu-Natal, South Africa, by comparing measurements with those obtained by the Amplicor HIV-1 Monitor (r(2)=0.88). Nucleic acid extraction by magnetic micro beads followed by real time PCR is a reliable, sensitive, rapid and simple procedure to quantify HIV-1 RNA in breast milk and allows for PCR inhibitors found frequently in these samples.

  13. Study of HIV-1 Evolution by Coding Thory and Entropic Chaos Degree

    NASA Astrophysics Data System (ADS)

    Sato, Keiko

    2011-01-01

    We studied the evolution of HIV-1 (Human Immuno-deficiency Virus Type 1) by means of coding theory and information dynamics. More precisely, (1) we applied various artificial codes to look for the similarity between these codes and the code of HIV-1; (2) the entropic chaos degree was used to describe the evolution of HIV-1.

  14. Activation of HIV-1 with Nanoparticle-Packaged Small-Molecule Protein Phosphatase-1-Targeting Compound

    PubMed Central

    Smith, Kahli A.; Lin, Xionghao; Bolshakov, Oleg; Griffin, James; Niu, Xiaomei; Kovalskyy, Dmytro; Ivanov, Andrey; Jerebtsova, Marina; Taylor, Robert E.; Akala, Emmanuel; Nekhai, Sergei

    2015-01-01

    Complete eradication of HIV-1 infection is impeded by the existence of latent HIV-1 reservoirs in which the integrated HIV-1 provirus is transcriptionally inactive. Activation of HIV-1 transcription requires the viral Tat protein and host cell factors, including protein phosphatase-1 (PP1). We previously developed a library of small compounds that targeted PP1 and identified a compound, SMAPP1, which induced HIV-1 transcription. However, this compound has a limited bioavailability in vivo and may not be able to reach HIV-1-infected cells and induce HIV-1 transcription in patients. We packaged SMAPP1 in polymeric polyethylene glycol polymethyl methacrylate nanoparticles and analyzed its release and the effect on HIV-1 transcription in a cell culture. SMAPP1 was efficiently packaged in the nanoparticles and released during a 120-hr period. Treatment of the HIV-1-infected cells with the SMAPP1-loaded nanoparticles induced HIV-1 transcription. Thus, nanoparticles loaded with HIV-1-targeting compounds might be useful for future anti-HIV-1 therapeutics. PMID:26839837

  15. Activation of HIV-1 with Nanoparticle-Packaged Small-Molecule Protein Phosphatase-1-Targeting Compound.

    PubMed

    Smith, Kahli A; Lin, Xionghao; Bolshakov, Oleg; Griffin, James; Niu, Xiaomei; Kovalskyy, Dmytro; Ivanov, Andrey; Jerebtsova, Marina; Taylor, Robert E; Akala, Emmanuel; Nekhai, Sergei

    2015-01-01

    Complete eradication of HIV-1 infection is impeded by the existence of latent HIV-1 reservoirs in which the integrated HIV-1 provirus is transcriptionally inactive. Activation of HIV-1 transcription requires the viral Tat protein and host cell factors, including protein phosphatase-1 (PP1). We previously developed a library of small compounds that targeted PP1 and identified a compound, SMAPP1, which induced HIV-1 transcription. However, this compound has a limited bioavailability in vivo and may not be able to reach HIV-1-infected cells and induce HIV-1 transcription in patients. We packaged SMAPP1 in polymeric polyethylene glycol polymethyl methacrylate nanoparticles and analyzed its release and the effect on HIV-1 transcription in a cell culture. SMAPP1 was efficiently packaged in the nanoparticles and released during a 120-hr period. Treatment of the HIV-1-infected cells with the SMAPP1-loaded nanoparticles induced HIV-1 transcription. Thus, nanoparticles loaded with HIV-1-targeting compounds might be useful for future anti-HIV-1 therapeutics. PMID:26839837

  16. Latency reversal and viral clearance to cure HIV-1.

    PubMed

    Margolis, David M; Garcia, J Victor; Hazuda, Daria J; Haynes, Barton F

    2016-07-22

    Research toward a cure for human immunodeficiency virus type 1 (HIV-1) infection has joined prevention and treatment efforts in the global public health agenda. A major approach to HIV eradication envisions antiretroviral suppression, paired with targeted therapies to enforce the expression of viral antigen from quiescent HIV-1 genomes, and immunotherapies to clear latent infection. These strategies are targeted to lead to viral eradication--a cure for AIDS. Paired testing of latency reversal and clearance strategies has begun, but additional obstacles to HIV eradication may emerge. Nevertheless, there is reason for optimism that advances in long-acting antiretroviral therapy and HIV prevention strategies will contribute to efforts in HIV cure research and that the implementation of these efforts will synergize to markedly blunt the effect of the HIV pandemic on society.

  17. Latency reversal and viral clearance to cure HIV-1.

    PubMed

    Margolis, David M; Garcia, J Victor; Hazuda, Daria J; Haynes, Barton F

    2016-07-22

    Research toward a cure for human immunodeficiency virus type 1 (HIV-1) infection has joined prevention and treatment efforts in the global public health agenda. A major approach to HIV eradication envisions antiretroviral suppression, paired with targeted therapies to enforce the expression of viral antigen from quiescent HIV-1 genomes, and immunotherapies to clear latent infection. These strategies are targeted to lead to viral eradication--a cure for AIDS. Paired testing of latency reversal and clearance strategies has begun, but additional obstacles to HIV eradication may emerge. Nevertheless, there is reason for optimism that advances in long-acting antiretroviral therapy and HIV prevention strategies will contribute to efforts in HIV cure research and that the implementation of these efforts will synergize to markedly blunt the effect of the HIV pandemic on society. PMID:27463679

  18. The HIV-1 Epidemic: Low- to Middle-Income Countries

    PubMed Central

    Shao, Yiming; Williamson, Carolyn

    2012-01-01

    Low- to middle-income countries bear the overwhelming burden of the human immunodeficiency virus type 1 (HIV-1) epidemic in terms of the numbers of their citizens living with HIV/AIDS (acquired immunodeficiency syndrome), the high degrees of viral diversity often involving multiple HIV-1 clades circulating within their populations, and the social and economic factors that compromise current control measures. Distinct epidemics have emerged in different geographical areas. These epidemics differ in their severity, the population groups they affect, their associated risk behaviors, and the viral strains that drive them. In addition to inflicting great human cost, the high burden of HIV infection has a major impact on the social and economic development of many low- to middle-income countries. Furthermore, the high degrees of viral diversity associated with multiclade HIV epidemics impacts viral diagnosis and pathogenicity and treatment and poses daunting challenges for effective vaccine development. PMID:22393534

  19. An HIV-1 transmission case possibly associated with manicure care.

    PubMed

    Matsuda, Elaine Monteiro; Coelho, Luana Portes Ozório; Pimentel, Victor Figueiredo; Onias, Humberto Barjud; Brigido, Luís Fernando de Macedo

    2014-11-01

    A recently diagnosed 22-year-old female with no history of transmission risk factors prompted a thorough investigation of possible alternative risk factors. As the patient had evidence of advanced disease and laboratory data compatible with long-standing infection, past events were reviewed. About 10 years ago the patient shared manicure utensils with an older cousin, later known to be HIV infected; this prompted the phylogenetic analysis of the HIV sequences of both patients. Phylogenetic analyses of partial HIV-1 polymerase and envelope sequences from both patients revealed highly related sequences, with an estimated common ancestor date (about 11 years ago) that coincided with the putative sharing of manicure instruments, during a time in which the cousin was not virally suppressed. Taken together, the information about the infection of this patient suggests the use of shared manicure instruments as an alternative route of fomite HIV-1 transmission.

  20. Persistent HIV-1 replication maintains the tissue reservoir during therapy.

    PubMed

    Lorenzo-Redondo, Ramon; Fryer, Helen R; Bedford, Trevor; Kim, Eun-Young; Archer, John; Kosakovsky Pond, Sergei L; Chung, Yoon-Seok; Penugonda, Sudhir; Chipman, Jeffrey G; Fletcher, Courtney V; Schacker, Timothy W; Malim, Michael H; Rambaut, Andrew; Haase, Ashley T; McLean, Angela R; Wolinsky, Steven M

    2016-02-01

    Lymphoid tissue is a key reservoir established by HIV-1 during acute infection. It is a site associated with viral production, storage of viral particles in immune complexes, and viral persistence. Although combinations of antiretroviral drugs usually suppress viral replication and reduce viral RNA to undetectable levels in blood, it is unclear whether treatment fully suppresses viral replication in lymphoid tissue reservoirs. Here we show that virus evolution and trafficking between tissue compartments continues in patients with undetectable levels of virus in their bloodstream. We present a spatial and dynamic model of persistent viral replication and spread that indicates why the development of drug resistance is not a foregone conclusion under conditions in which drug concentrations are insufficient to completely block virus replication. These data provide new insights into the evolutionary and infection dynamics of the virus population within the host, revealing that HIV-1 can continue to replicate and replenish the viral reservoir despite potent antiretroviral therapy. PMID:26814962

  1. Persistent HIV-1 replication maintains the tissue reservoir during therapy

    PubMed Central

    Bedford, Trevor; Kim, Eun-Young; Archer, John; Pond, Sergei L. Kosakovsky; Chung, Yoon-Seok; Penugonda, Sudhir; Chipman, Jeffrey; Fletcher, Courtney V.; Schacker, Timothy W.; Malim, Michael H.; Rambaut, Andrew; Haase, Ashley T.; McLean, Angela R.; Wolinsky, Steven M.

    2015-01-01

    Lymphoid tissue is a key reservoir established by HIV-1 during acute infection. It is a site of viral production, storage of viral particles in immune complexes, and viral persistence. Whilst combinations of antiretroviral drugs usually suppress viral replication and reduce viral RNA to undetectable levels in blood, it is unclear whether treatment fully suppresses viral replication in lymphoid tissue reservoirs. Here we show that virus evolution and trafficking between tissue compartments continues in patients with undetectable levels of virus in their bloodstream. A spatial dynamic model of persistent viral replication and spread explains why the development of drug resistance is not a foregone conclusion under conditions where drug concentrations are insufficient to completely block virus replication. These data provide fresh insights into the evolutionary and infection dynamics of the virus population within the host, revealing that HIV-1 can continue to replicate and refill the viral reservoir despite potent antiretroviral therapy. PMID:26814962

  2. New drugs for HIV-1: challenges and novel candidates.

    PubMed

    Ward, Christopher James Kevin

    2010-10-01

    The XVIII International Conference of the International AIDS Society held in Vienna on the 18-23 July 2010 brought together scientists, clinicians, policymakers, people living with HIV/AIDS and journalists from across the globe. Keynote speakers relevant to the theme of this report included Sharon Lewin (Alfred Hospital, Melbourne, Australia) and Tae-Wook Chun (National Institute of Allergy and Infectious Diseases, MA, USA), among others. A total of 19,100 delegates from across 193 countries attended the conference, which comprised 248 sessions, accompanied by 6238 abstracts and posters. The remit was broad, covering scientific, social and political aspects of the HIV/AIDS epidemic. This article focuses on the issue of eliminating latent reservoirs of HIV-1 infection, highlighting selected potential novel therapeutic interventions in overcoming challenges in HIV-1 suppression.

  3. Immunologic abnormalities related to antigenaemia during HIV-1 infection.

    PubMed Central

    De Paoli, P; Battistin, S; Crovatto, M; Modolo, M L; Carbone, A; Tirelli, U; Santini, G

    1988-01-01

    The expression of phenotypic markers on T and B lymphocytes in long-term human immunodeficiency virus type 1 (HIV-1) seropositive, antigen negative patients, in seropositive, antigen positive individuals without AIDS and in seronegative intravenous drug abusers was examined by two colour flow cytometry. Seropositive, antigen positive patients showed decreased CD4+ lymphocyte numbers, causing lower CD4/CD8 ratios when compared to seropositive, antigen negative subjects. While CD4 CDw29+ (4B4) lymphocytes are selectively reduced in seropositive, antigen negative individuals, both CD4 CDw29+ and CD4 CD45R+ (2H4) lymphocytes are decreased when antigenaemia is present. An increased percentage of CD3 HLA DR+ activated T lymphocytes and of CD20+ (B1) Leu 8 negative activated B cells was seen in HIV-1 seropositive antigen positive patients. These results demonstrate that, in long-term seropositive individuals, antigenaemia is associated with peculiar phenotypic changes of lymphocyte subsets. PMID:2976619

  4. Quantitative Image Analysis of HIV-1 Infection in Lymphoid Tissue

    NASA Astrophysics Data System (ADS)

    Haase, Ashley T.; Henry, Keith; Zupancic, Mary; Sedgewick, Gerald; Faust, Russell A.; Melroe, Holly; Cavert, Winston; Gebhard, Kristin; Staskus, Katherine; Zhang, Zhi-Qiang; Dailey, Peter J.; Balfour, Henry H., Jr.; Erice, Alejo; Perelson, Alan S.

    1996-11-01

    Tracking human immunodeficiency virus-type 1 (HIV-1) infection at the cellular level in tissue reservoirs provides opportunities to better understand the pathogenesis of infection and to rationally design and monitor therapy A quantitative technique was developed to determine viral burden in two important cellular compartments in lymphoid tissues. Image analysis and in situ hybridization were combined to show that in the presymptomatic stages of infection there is a large, relatively stable pool of virions on the surfaces of follicular dendritic cells and a smaller pool of productively infected cells Despite evidence of constraints on HIV-1 replication in the infected cell population in lymphoid tissues, estimates of the numbers of these cells and the virus they could produce are consistent with the quantities of virus that have been detected in the bloodstream. The cellular sources of virus production and storage in lymphoid tissues can now be studied with this approach over the course of infection and treatment.

  5. Characterization of a folding intermediate from HIV-1 ribonuclease H.

    PubMed Central

    Kern, G.; Handel, T.; Marqusee, S.

    1998-01-01

    The RNase H domain from HIV-1 (HIV RNase H) encodes an essential retroviral activity. Refolding of the isolated HIV RNase H domain shows a kinetic intermediate detectable by stopped-flow far UV circular dichroism and pulse-labeling H/D exchange. In this intermediate, strands 1, 4, and 5 as well as helices A and D appear to be structured. Compared to its homolog from Escherichia coli, the rate limiting step in refolding of HIV RNase H appears closer to the native state. We have modeled this kinetic intermediate using a C-terminal deletion fragment lacking helix E. Like the kinetic intermediate, this variant folds rapidly and shows a decrease in stability. We propose that inhibition of the docking of helix E to this folding intermediate may present a novel strategy for anti HIV-1 therapy. PMID:9792104

  6. Sulfonation Pathway Inhibitors Block Reactivation of Latent HIV-1

    PubMed Central

    Murry, Jeffrey P.; Godoy, Joseph; Mukim, Amey; Swann, Justine; Bruce, James W.; Ahlquist, Paul; Bosque, Alberto; Planelles, Vicente; Spina, Celsa A.; Young, John A. T.

    2015-01-01

    Long-lived pools of latently infected cells are a significant barrier to the development of a cure for HIV-1 infection. A better understanding of the mechanisms of reactivation from latency is needed to facilitate the development of novel therapies that address this problem. Here we show that chemical inhibitors of the sulfonation pathway prevent virus reactivation, both in latently infected J-Lat and U1 cell lines and in a primary human CD4+ T cell model of latency. In each of these models, sulfonation inhibitors decreased transcription initiation from the HIV-1 promoter. These inhibitors block transcription initiation at a step that lies downstream of nucleosome remodeling and affects RNA polymerase II recruitment to the viral promoter. These results suggest that the sulfonation pathway acts by a novel mechanism to regulate efficient virus transcription initiation during reactivation from latency, and further that augmentation of this pathway could be therapeutically useful. PMID:25310595

  7. Novel mouse models for understanding HIV-1 pathogenesis.

    PubMed

    Joseph, Aviva; Sango, Kaori; Goldstein, Harris

    2009-01-01

    Small animal models in which in vivo HIV-1 infection, pathogenesis, and immune responses can be studied would permit both basic research on the biology of the disease, as well as a system to rapidly screen developmental therapeutics and/or vaccines. To date, the most widely-used models have been the severe combined immunodeficient (SCID)-hu (also known as the thy/liv SCID-hu) and the huPBL-SCID mouse models. Recently three new models have emerged, i.e., the intrasplenic huPBL/SPL-SCID model, the NOD/SCID/IL2Rgamma(null) mouse model, and the Rag2(-/-)gamma(c) (-/-) mouse model. Details on the construction, maintenance and HIV-1 infection of these models are discussed.

  8. Progress and Perspectives on HIV-1 microbicide development.

    PubMed

    Alexandre, Kabamba B; Mufhandu, Hazel T; London, Grace M; Chakauya, E; Khati, M

    2016-10-01

    The majority of HIV-1 infections occur via sexual intercourse. Women are the most affected by the epidemic, particularly in developing countries, due to their socio-economic dependence on men and the fact that they are often victims of gender based sexual violence. Despite significant efforts that resulted in the reduction of infection rates in some countries, there is still need for effective prevention methods against the virus. One of these methods for preventing sexual transmission in women is the use of microbicides. In this review we provide a summary of the progress made toward the discovery of affordable and effective HIV-1 microbicides and suggest future directions. We show that there is a wide range of compounds that have been proposed as potential microbicides. Although most of them have so far failed to show protection in humans, there are many promising ones currently in pre-clinical studies and in clinical trials. PMID:27429040

  9. HIV-1, Reactive Oxygen Species and Vascular Complications

    PubMed Central

    Porter, Kristi M.; Sutliff, Roy L.

    2012-01-01

    Over 1 million people in the United States and 33 million individuals worldwide suffer from HIV/AIDS. Since its discovery, HIV/AIDS has been associated with an increased susceptibility to opportunistic infection due to immune dysfunction. Highly active antiretroviral therapies (HAART) restore immune function and, as a result, people infected with HIV-1 are living longer. This improved survival of HIV-1 patients has revealed a previously unrecognized risk of developing vascular complications, such as atherosclerosis and pulmonary hypertension. The mechanisms underlying these HIV-associated vascular disorders are poorly understood. However, HIV-induced elevations in reactive oxygen species, including superoxide and hydrogen peroxide, may contribute to vascular disease development and progression by altering cell function and redox-sensitive signaling pathways. In this review, we summarize the clinical and experimental evidence demonstrating HIV- and HIV antiretroviral therapy-induced alterations in reactive oxygen species (ROS) and how these effects likely contribute to vascular dysfunction and disease. PMID:22564529

  10. HIV-1 and hijacking of the host immune system: the current scenario.

    PubMed

    Imran, Muhammad; Manzoor, Sobia; Saalim, Muhammad; Resham, Saleha; Ashraf, Javed; Javed, Aneela; Waqar, Ahmed Bilal

    2016-10-01

    Human immunodeficiency virus (HIV) infection is a major health burden across the world which leads to the development of acquired immune deficiency syndrome (AIDS). This review article discusses the prevalence of HIV, its major routes of transmission, natural immunity, and evasion from the host immune system. HIV is mostly prevalent in Sub-Saharan Africa and low income countries. It is mostly transmitted by sharing syringe needles, blood transfusion, and sexual routes. The host immune system is categorized into three main types; the innate, the adaptive, and the intrinsic immune system. Regarding the innate immune system against HIV, the key players are mucosal membrane, dendritic cells (DCs), complement system, interferon, and host Micro RNAs. The major components of the adaptive immune system exploited by HIV are T cells mainly CD4+ T cells and B cells. The intrinsic immune system confronted by HIV involves (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G) APOBEC3G, tripartite motif 5-α (TRIM5a), terherin, and (SAM-domain HD-domain containing protein) SAMHD1. HIV-1 efficiently interacts with the host immune system, exploits the host machinery, successfully replicates and transmits from one cell to another. Further research is required to explore evasion strategies of HIV to develop novel therapeutic approaches against HIV.

  11. Exercise and Human Immunodeficiency Virus (HIV-1) Infection

    NASA Technical Reports Server (NTRS)

    Lawless, DeSales; Jackson, Catherine G. R.; Greenleaf, John E.

    1995-01-01

    The human immune system is highly efficient and remarkably protective when functioning properly. Similar to other physiological systems, it functions best when the body is maintained with a balanced diet, sufficient rest and a moderately stress-free lifestyle. It can be disrupted by inappropriate drug use and extreme emotion or exertion. The functioning of normal or compromised immune systems can be enhanced by properly prescribed moderate exercise conditioning regimens in healthy people, and in some human immunodeficiency virus (HIV-1)-infected patients but not in others who unable to complete an interval training program. Regular exercise conditioning in healthy people reduces cardiovascular risk factors, increases stamina, facilitates bodyweight control, and reduces stress by engendering positive feelings of well-being. Certain types of cancer may also be suppressed by appropriate exercise conditioning. Various exercise regimens are being evaluated as adjunct treatments for medicated patients with the HIV-1 syndrome. Limited anecdotal evidence from patients suggests that moderate exercise conditioning is per se responsible for their survival well beyond expectancy. HIV-1-infected patients respond positively, both physiologically and psychologically, to moderate exercise conditioning. However, the effectiveness of any exercise treatment programme depends on its mode, frequency, intensity and duration when prescribed o complement the pathological condition of the patient. The effectiveness of exercise conditioning regimens in patients with HIV-1 infection is reviewed in this article. In addition, we discuss mechanisms and pathways, involving the interplay of psychological and physiological factors, through which the suppressed immune system can be enhanced. The immune modulators discussed are endogenous opioids, cytokines, neurotransmitters and other hormones. Exercise conditioning treatment appears to be more effective when combined with other stress management

  12. Identification of cellular factors binding to acetylated HIV-1 integrase.

    PubMed

    Allouch, Awatef; Cereseto, Anna

    2011-11-01

    The viral protein integrase (IN) catalyzes the integration of the HIV-1 cDNA into the host cellular genome. We have recently demonstrated that IN is acetylated by a cellular histone acetyltransferase, p300, which modifies three lysines located in the C-terminus of the viral factor (Cereseto et al. in EMBO J 24:3070-3081, 2005). This modification enhances IN catalytic activity, as demonstrated by in vitro assays. Consistently, mutations introduced in the targeted lysines greatly decrease the efficiency of HIV-1 integration. Acetylation was proven to regulate protein functions by modulating protein-protein interactions. HIV-1 to efficiently complete its replication steps, including the integration reaction, requires interacting with numerous cellular factors. Therefore, we sought to investigate whether acetylation might modulate the interaction between IN and the cellular factors. To this aim we performed a yeast two-hybrid screening that differs from the screenings so far performed (Rain et al. in Methods 47:291-297, 2009; Studamire and Goff in Retrovirology 5:48, 2008) for using as bait IN constitutively acetylated. From this analysis we have identified thirteen cellular factors involved in transcription, chromatin remodeling, nuclear transport, RNA binding, protein synthesis regulation and microtubule organization. To validate these interactions, binding assays were performed showing that acetylation increases the affinity of IN with specific factors. Nevertheless, few two-hybrid hits bind with the same affinity the acetylated and the unmodified IN. These results further underlie the relevance of IN post-translational modification by acetylation in HIV-1 replication cycle.

  13. Spatial phylodynamics of HIV-1 epidemic emergence in east Africa

    PubMed Central

    Gray, Rebecca R.; Tatem, Andrew J.; Lamers, Susanna; Hou, Wei; Laeyendecker, Oliver; Serwadda, David; Sewankambo, Nelson; Gray, Ronald H.; Wawer, Maria; Quinn, Thomas C.; Goodenow, Maureen M.; Salemi, Marco

    2009-01-01

    Design We sought to investigate the evolutionary and historical reasons for the different epidemiological patterns of HIV-1 in the early epidemic. In order to characterize the demographic history of HIV-1 subtypes A and D in east Africa, we examined molecular epidemiology, geographical and historical data. Methodology We employed high-resolution phylodynamics to investigate the introduction of HIV-1A and D into east Africa, the geographic trends of viral spread, and the demographic growth of each subtype. We also used geographic information system data to investigate human migration trends, population growth, and human mobility. Results HIV-1A and D were introduced into east Africa after 1950 and spread exponentially during the 1970s, concurrent with eastward expansion. Spatiotemporal data failed to explain the establishment and spread of HIV based on urban population growth and migration. The low prevalence of the virus in the Democratic Republic of Congo before and after the emergence of the pandemic was, however, consistent with regional accessibility data, highlighting the difficulty in travel between major population centers in central Africa. In contrast, the strong interconnectivity between population centers across the east African region since colonial times has likely fostered the rapid growth of the epidemic in this locale. Conclusion This study illustrates how phylodynamic analysis of pathogens informed by geospatial data can provide a more holistic and evidence-based interpretation of past epidemics. We advocate that this ‘landscape phylodynamics’ approach has the potential to provide a framework both to understand epidemics' spread and to design optimal intervention strategies. PMID:19644346

  14. Drug-Induced Reactivation of Apoptosis Abrogates HIV-1 Infection

    PubMed Central

    Hanauske-Abel, Hartmut M.; Saxena, Deepti; Palumbo, Paul E.; Hanauske, Axel-Rainer; Luchessi, Augusto D.; Cambiaghi, Tavane D.; Hoque, Mainul; Spino, Michael; Gandolfi, Darlene D'Alliessi; Heller, Debra S.; Singh, Sukhwinder; Park, Myung Hee; Cracchiolo, Bernadette M.; Tricta, Fernando; Connelly, John; Popowicz, Anthony M.; Cone, Richard A.; Holland, Bart; Pe’ery, Tsafi; Mathews, Michael B.

    2013-01-01

    HIV-1 blocks apoptosis, programmed cell death, an innate defense of cells against viral invasion. However, apoptosis can be selectively reactivated in HIV-infected cells by chemical agents that interfere with HIV-1 gene expression. We studied two globally used medicines, the topical antifungal ciclopirox and the iron chelator deferiprone, for their effect on apoptosis in HIV-infected H9 cells and in peripheral blood mononuclear cells infected with clinical HIV-1 isolates. Both medicines activated apoptosis preferentially in HIV-infected cells, suggesting that the drugs mediate escape from the viral suppression of defensive apoptosis. In infected H9 cells, ciclopirox and deferiprone enhanced mitochondrial membrane depolarization, initiating the intrinsic pathway of apoptosis to execution, as evidenced by caspase-3 activation, poly(ADP-ribose) polymerase proteolysis, DNA degradation, and apoptotic cell morphology. In isolate-infected peripheral blood mononuclear cells, ciclopirox collapsed HIV-1 production to the limit of viral protein and RNA detection. Despite prolonged monotherapy, ciclopirox did not elicit breakthrough. No viral re-emergence was observed even 12 weeks after drug cessation, suggesting elimination of the proviral reservoir. Tests in mice predictive for cytotoxicity to human epithelia did not detect tissue damage or activation of apoptosis at a ciclopirox concentration that exceeded by orders of magnitude the concentration causing death of infected cells. We infer that ciclopirox and deferiprone act via therapeutic reclamation of apoptotic proficiency (TRAP) in HIV-infected cells and trigger their preferential elimination. Perturbations in viral protein expression suggest that the antiretroviral activity of both drugs stems from their ability to inhibit hydroxylation of cellular proteins essential for apoptosis and for viral infection, exemplified by eIF5A. Our findings identify ciclopirox and deferiprone as prototypes of selectively cytocidal

  15. Mother-to-Child HIV-1 Transmission Events Are Differentially Impacted by Breast Milk and Its Components from HIV-1-Infected Women.

    PubMed

    Shen, Ruizhong; Achenbach, Jenna; Shen, Yue; Palaia, Jana; Rahkola, Jeremy T; Nick, Heidi J; Smythies, Lesley E; McConnell, Michelle; Fowler, Mary G; Smith, Phillip D; Janoff, Edward N

    2015-01-01

    Breast milk is a vehicle of infection and source of protection in post-natal mother-to-child HIV-1 transmission (MTCT). Understanding the mechanism by which breast milk limits vertical transmission will provide critical insight into the design of preventive and therapeutic approaches to interrupt HIV-1 mucosal transmission. However, characterization of the inhibitory activity of breast milk in human intestinal mucosa, the portal of entry in postnatal MTCT, has been constrained by the limited availability of primary mucosal target cells and tissues to recapitulate mucosal transmission ex vivo. Here, we characterized the impact of skimmed breast milk, breast milk antibodies (Igs) and non-Ig components from HIV-1-infected Ugandan women on the major events of HIV-1 mucosal transmission using primary human intestinal cells and tissues. HIV-1-specific IgG antibodies and non-Ig components in breast milk inhibited the uptake of Ugandan HIV-1 isolates by primary human intestinal epithelial cells, viral replication in and transport of HIV-1- bearing dendritic cells through the human intestinal mucosa. Breast milk HIV-1-specific IgG and IgA, as well as innate factors, blocked the uptake and transport of HIV-1 through intestinal mucosa. Thus, breast milk components have distinct and complementary effects in reducing HIV-1 uptake, transport through and replication in the intestinal mucosa and, therefore, likely contribute to preventing postnatal HIV-1 transmission. Our data suggests that a successful preventive or therapeutic approach would require multiple immune factors acting at multiple steps in the HIV-1 mucosal transmission process. PMID:26680219

  16. Rapid Antiretroviral Therapy Initiation for Women in an HIV-1 Prevention Clinical Trial Experiencing Primary HIV-1 Infection during Pregnancy or Breastfeeding.

    PubMed

    Morrison, Susan; John-Stewart, Grace; Egessa, John J; Mubezi, Sezi; Kusemererwa, Sylvia; Bii, Dennis K; Bulya, Nulu; Mugume, Francis; Campbell, James D; Wangisi, Jonathan; Bukusi, Elizabeth A; Celum, Connie; Baeten, Jared M

    2015-01-01

    During an HIV-1 prevention clinical trial in East Africa, we observed 16 cases of primary HIV-1 infection in women coincident with pregnancy or breastfeeding. Nine of eleven pregnant women initiated rapid combination antiretroviral therapy (ART), despite having CD4 counts exceeding national criteria for ART initiation; breastfeeding women initiated ART or replacement feeding. Rapid ART initiation during primary HIV-1 infection during pregnancy and breastfeeding is feasible in this setting.

  17. Genetic diversity and primary resistance among HIV-1-positive patients from Maringá, Paraná, Brazil.

    PubMed

    Gaspareto, Karine Vieira; Mello, Flávia Myrian Martins de Almeida; Dias, José Ricardo Colleti; Meneguetti, Vera Alice Fernandes; Storti, Marta Evelyn Giansante; Ferreira, João Leandro de Paula; Lança, André Minhoto; Rodrigues, Rosângela; Brígido, Luis Fernando de Macedo; Teixeira, Jorge Juarez Vieira; Bertolini, Dennis Armando

    2012-08-01

    The objective of this study is to identify subtypes of Human Immunodeficiency Virus type 1 (HIV-1) and to analyze the presence of mutations associated to antiretroviral resistance in the protease (PR) and reverse transcriptase (RT) regions from 48 HIV-1 positive treatment naïve patients from an outpatient clinic in Maringá, Paraná, Brazil. Sequencing was conducted using PR, partial RT and group-specific antigen gene (gag) nested PCR products from retrotranscribed RNA. Transmitted resistance was determined according to the Surveillance Drug Resistance Mutation List (SDRM) algorithm. Phylogenetic and SimPlot analysis of concatenated genetic segments classified sequences as subtype B 19/48 (39.6%), subtype C 12/48 (25%), subtype F 4/48 (8.3%), with 13/48 (27.1%) recombinant forms. Most recombinant forms were B mosaics (B/F 12.5%, B/C 10.4%), with one C/F (2.1%) and one complex B/C/F mosaic (2.1%). Low levels of transmitted resistance were found in this study, 2/48 (2.1% to NRTIs and 2.1% for PI). This preliminary data may subsidize the monitoring of the HIV evolution in the region.

  18. Protein grafting of an HIV-1-inhibiting epitope

    NASA Astrophysics Data System (ADS)

    Sia, Samuel K.; Kim, Peter S.

    2003-08-01

    Protein grafting, the transfer of a binding epitope of one ligand onto the surface of another protein, is a potentially powerful technique for presenting peptides in preformed and active three-dimensional conformations. Its utility, however, has been limited by low biological activity of the designed ligands and low tolerance of the protein scaffolds to surface substitutions. Here, we graft the complete binding epitope (19 nonconsecutive amino acids with a solvent-accessible surface area of >2,000 Å2) of an HIV-1 C-peptide, which is derived from the C-terminal region of HIV-1 gp41 and potently inhibits HIV-1 entry into cells, onto the surface of a GCN4 leucine zipper. The designed peptide, named C34coil, displays a potent antiviral activity approaching that of the native ligand. Moreover, whereas the linear C-peptide is unstructured and sensitive to degradation by proteases, C34coil is well structured, conformationally stable, and exhibits increased resistance to proteolytic degradation compared with the linear peptide. In addition to being a structured antiviral inhibitor, C34coil may also serve as the basis for the development of an alternative class of immunogens. This study demonstrates that "one-shot" protein grafting, without subsequent rounds of optimization, can be used to create ligands with structural conformations and improved biomedical properties.

  19. Combinatorial RNAi against HIV-1 using extended short hairpin RNAs.

    PubMed

    Liu, Ying Poi; von Eije, Karin Jasmijn; Schopman, Nick C T; Westerink, Jan-Tinus; ter Brake, Olivier; Haasnoot, Joost; Berkhout, Ben

    2009-10-01

    RNA interference (RNAi) is a widely used gene suppression tool that holds great promise as a novel antiviral approach. However, for error-prone viruses including human immunodeficiency virus type 1(HIV-1), a combinatorial approach against multiple conserved sequences is required to prevent the emergence of RNAi-resistant escape viruses. Previously, we constructed extended short hairpin RNAs (e-shRNAs) that encode two potent small interfering RNAs (siRNAs) (e2-shRNAs). We showed that a minimal hairpin stem length of 43 base pairs (bp) is needed to obtain two functional siRNAs. In this study, we elaborated on the e2-shRNA design to make e-shRNAs encoding three or four antiviral siRNAs. We demonstrate that siRNA production and the antivira