A Salmonella typhi conjugated vaccine was prepared by covalently linking the antigenic O-polysaccharide, selectively activated by periodate oxidation, to tetanus toxoid via reductive amination. The immunogenicity of the conjugate (O-TT) was examined by injecting Balb/c mice with 5 micrograms of the conjugate and Alhydrogel as adjuvant, boosting 14 and 28 days after the primary immunization, and quantification of the development of anti-polysaccharide and anti-tetanus toxoid antibodies by enzyme-linked immunosorbent assay. Mean anti-O-chain titres after the first and second boost were 129 and 502, respectively, while anti-tetanus toxoid titres were 159 and 1000, respectively. Anti-O-polysaccharide antibodies exhibited complement-mediated bactericidal activity against S. typhi. Immunized mice were fully protected against challenge with 10 LD50 of S. typhi Ty2 (p < 0.001) and partially protected against challenge with 100 LD50 of S. typhi Ty2 (p < 0.04). PMID:7526567
Saxena, M; Di Fabio, J L
Invasive meningococcal disease is a serious infection that occurs worldwide. It is caused by Neisseria meningitidis, of which six serogroups (A, B, C, W-135, X, and Y) are responsible for most infections. The case fatality rate of meningococcal disease remains high and can lead to significant sequelae. Vaccination remains the best strategy to prevent meningococcal disease. Polysaccharide vaccines were initially introduced in the late 1960s but their limitations (poor immunogenicity in infants and toddlers and hyporesponsiveness after repeated doses) have led to the development and use of meningococcal conjugate vaccines, which overcome these limitations. Two quadrivalent conjugated meningococcal vaccines – MenACWY-DT (Menactra®) and MenACWY-CRM197 (Menveo®) – using diphtheria toxoid or a mutant protein, respectively, as carrier proteins have already been licensed in the US. Recently, a quadrivalent meningococcal vaccine conjugated to tetanus toxoid (MenACWY-TT; Nimenrix®) was approved for use in Europe in 2012. The immunogenicity of MenACWY-TT, its reactogenicity and safety profile, as well as its coadministration with other vaccines are discussed in this review. Clinical trials showed that MenACWY-TT was immunogenic in children above the age of 12 months, adolescents, and adults, and has an acceptable reactogenicity and safety profile. Its coadministration with several other vaccines that are commonly used in children, adolescents, and adults did not affect the immunogenicity of MenACWY-TT or the coadministered vaccine, nor did it affect its reactogenicity and safety. Other studies are now ongoing in order to determine the immunogenicity, reactogenicity, and safety of MenACWY-TT in infants from the age of 6 weeks.
Hedari, Carine P; Khinkarly, Rima W; Dbaibo, Ghassan S
Immunogenicity and reactogenicity of diphtheria, tetanus and pertussis toxoids combined with inactivated polio vaccine, when administered concomitantly with or as a diluent for a Hib conjugate vaccine
In an open trial, 400 infants were randomized to vaccination with a combined diphtheria–tetanus–pertussis-inactivated polio vaccine (DTaP-IPV) either mixed with a Haemophilus influenzae type b (Hib) tetanus toxoid conjugate immediately before injection (DTaP-IPV\\/Hib (mix)) or given concurrently with the Hib conjugate at separate injection sites (DTaP-IPV+Hib (sep)). The pertussis component consisted of pertussis toxoid alone. The vaccines were given intramuscularly
Nina Knutsson; Birger Trollfors; John Taranger; Elisabet Bergfors; Valter Sundh; Teresa Lagergård; Erik Östergaard; Helen Cicirello; Helena Käyhty
In this study it was demonstrated that the immunogenicity of Vi polysaccharide–diphtheria toxoid conjugates was related to the physical and chemical structure of the conjugate. Conjugates were prepared in two steps, firstly binding adipic acid dihydrazide (ADH) spacer molecules to diphtheria toxoid (DT) carrier protein then secondly binding varying amounts of this derivatized DT to a fixed amount of Vi
So Jung An; Yeon Kyung Yoon; Sudeep Kothari; Neha Kothari; Jeong Ah Kim; Eugene Lee; Deok Ryun Kim; Tai Hyun Park; Greg W. Smith; Rodney Carbis
We evaluated the safety and immunogenicity of a single dose of a new serogroup C O-deacetylated meningococcal polysaccharide–tetanus toxoid conjugate vaccine in 30 healthy adult volunteers. The vaccine was well tolerated with no serious adverse events and minimal local reactions and systemic symptoms. All subjects developed a fourfold or greater increase in serum bactericidal antibody (SBA) to serogroup C meningococcus.
Peter Richmond; David Goldblatt; Peter C Fusco; Joan D. S Fusco; Iver Heron; Sarah Clark; Ray Borrow; Francis Michon
Changes in the immunoglobulin G1 (IgG1)/IgG2 ratio following vaccination can indicate the activation of cellular control mechanisms typical of a T-cell-dependent response. We examined IgG subclass ratios in 17 healthy adults (26 to 55 years of age) before and 4 to 6 weeks following immunization with a quadrivalent meningococcal-polysaccharide diphtheria toxoid conjugate vaccine against serogroups A, C, Y, and W135. Serologic responses were determined by serum bactericidal antibody assay and serogroup-specific IgG, IgG1, and IgG2 enzyme-linked immunosorbent assay. Prevaccination serogroup A-specific IgG1/IgG2 ratios were <1 for all subjects and differed by subject for C, Y, and W-135. Postvaccination, significant increases in IgG, IgG1, and IgG2, were observed for all serogroups. Serogroup-specific IgG1/IgG2 ratios increased for group A (14/17 subjects, 88%), decreased in more than half of subjects for groups C (9/17, 53%) and W135 (12/17, 71%) and decreased for serogroup Y (16/17, 94%). IgG1/IgG2 ratios differed between individual vaccinees and were similar to the responses of adults who received pneumococcal conjugate vaccines or a monovalent C conjugate vaccine. Further studies on IgG subclasses following meningococcal polysaccharide and conjugate vaccination are needed.
Findlow, Helen; Southern, Jo; Mabey, Lesley; Balmer, Paul; Heyderman, Robert S.; Auckland, Cressida; Morris, Rhonwen; Miller, Elizabeth; Borrow, Ray
Group B streptococci (GBS) are the most common cause of bacterial sepsis and meningitis in neonates in the United States. Although the capsular polysaccharide of GBS is an important virulence factor, it is variably immunogenic in humans. In this report, we have increased the immunogenicity of GBS type II polysaccharide by coupling it to tetanus toxoid (TT). Like other GBS capsular polysaccharides, the type II polysaccharide has side chains terminating in sialic acid. Controlled periodate oxidation of native II polysaccharide resulted in the conversion of 7% of sialic acid residues to an analog of sialic acid, 5-acetamido-3,5-dideoxy-D-galactosyloctulosonic acid. TT was conjugated to free aldehyde groups created on the oxidized sialic acid residues by reductive amination. Serum from rabbits vaccinated with type II-TT conjugate (II-TT) vaccine contained antibodies specific to type II polysaccharide as well as to TT, whereas rabbits vaccinated with uncoupled native type II polysaccharide failed to produce a type-specific antibody response. Antibodies elicited by II-TT vaccine were serotype specific and mediated phagocytosis and killing in vitro of type II GBS by human peripheral blood leukocytes. Serum from rabbits vaccinated with II-TT vaccine provided 100% protection in a mouse model of GBS type II infection. Antibodies induced by II-TT vaccine were specific for the native but not desialylated type II polysaccharide, suggesting that an important antigenic epitope of II-TT vaccine was dependent on the presence of sialic acid. Therefore, the coupling strategy which selectively modified a portion of the sialic acid residues of types II polysaccharide before coupling the polysaccharide to TT preserved the epitope essential to protective immunity and enhanced the immunogenicity of the polysaccharide.
Paoletti, L C; Wessels, M R; Michon, F; DiFabio, J; Jennings, H J; Kasper, D L
The authors developed a simple rapid method for quantitation of free capsular polysaccharide ofHaemophilus influenzaetype b (polyribosyl ribitol phosphate, PRP) in PRP-tetanus toxoid conjugate vaccine based on acid precipitation of tetanus toxoid (TT). Acid hydrolysis of PRP during the assay was not detected. The conditions used in the assay did not precipitate unconjugated PRP or adipic acid dihydrazide derivatized PRP.
Yu-Yi Guo; Roger Anderson; James McIver; Rajesh K. Gupta; George R. Siber
In this study it was demonstrated that the immunogenicity of Vi polysaccharide-diphtheria toxoid conjugates was related to the physical and chemical structure of the conjugate. Conjugates were prepared in two steps, firstly binding adipic acid dihydrazide (ADH) spacer molecules to diphtheria toxoid (DT) carrier protein then secondly binding varying amounts of this derivatized DT to a fixed amount of Vi capsular polysaccharide purified from Salmonella enterica Serovar Typhi. As the amount of DT bound to the Vi increased the size of the conjugate increased but also the degree of cross-linking increased. The immunogenicity of the conjugates was tested in mice and measured by ELISA for anti Vi and anti DT IgG responses, and the results revealed a trend that as the amount of DT bound to the Vi increased the anti Vi responses increased. This study establishes a correlation between physico-chemical characteristics of the conjugate and the magnitude of the anti Vi and anti DT responses. PMID:21843575
An, So Jung; Yoon, Yeon Kyung; Kothari, Sudeep; Kothari, Neha; Kim, Jeong Ah; Lee, Eugene; Kim, Deok Ryun; Park, Tai Hyun; Smith, Greg W; Carbis, Rodney
We evaluated the functional activities of antibodies, serum bactericidal activity (SBA), and immunoglobulin G (IgG) antibody avidity indices, using sodium thiocyanate (NaSCN) elution, elicited after vaccination with fractional doses of the Haemophilus influenzae type b conjugate (polyribosylribitol phosphate [PRP] conjugated to tetanus toxoid [PRP-T]) vaccine. A cohort of 600 infants from the Dominican Republic were randomized to receive one of three regimens of the PRP-T vaccine at ages 2, 4, and 6 months: full doses (10 ?g of PRP antigen), one-half doses (5.0 ?g), and one-third doses (3.3 ?g) (J. Fernandez et al., Am. J. Trop. Med. Hyg. 62:485–490, 2000). Sixty serum samples, collected at age 7 months, with ?2.0 ?g of anti-PRP IgG per ml were randomly selected for avidity determinations. Geometric mean IgG concentrations were 13, 14, and 17 ?g/ml for infants who received the full-dose (n = 19), one-half-dose (n = 19), and one-third-dose (n = 22) regimens, respectively. SBA geometric mean titers (1/dilution) were 85.0, 82.0, and 76.1 in sera from infants receiving the full-, one-half-, and one-third-dose regimens, respectively. Avidity indices (mean ± standard error weighted average of NaSCN molar concentration × serum dilution factor) were 71.9 ± 9.4, 123.6 ± 26.8, and 150.9 ± 24.9 for the full-, one-half-, and one-third-dose regimens, respectively. Upon comparison, the only significant difference (P = 0.024) found was a greater avidity index for sera from infants receiving the one-third-dose regimen than for sera from infants receiving the the full-dose regimen. We conclude that fractional doses elicit similar functional antibody activities in infants with ?2 ?g of anti-PRP IgG per ml, corresponding to 89, 90, and 97% of infants receiving three doses of either the full concentration or one-half or one-third of the labeled concentration, respectively. This approach offers an alternative strategy for the prevention of H. influenzae type b disease in countries with limited resources.
Romero-Steiner, Sandra; Fernandez, Josefina; Biltoft, Christel; Wohl, Melissa E.; Sanchez, Jacqueline; Feris, Jesus; Balter, Sharon; Levine, Orin S.; Carlone, George M.
The present extension study, conducted in children originally vaccinated at 12–14 mo or 3–5 y of age, assessed antibody persistence and immune memory induced by an investigational tetravalent meningococcal serogroups A, C, W-135 and Y tetanus toxoid conjugate vaccine (MenACWY-TT). In the original study, participants were randomized to receive one dose of MenACWY-TT or licensed age-appropriate meningococcal control vaccines. Fifteen months post-vaccination, all participants underwent serum sampling to evaluate antibody persistence and participants previously vaccinated as toddlers received a polysaccharide challenge to assess immune memory development. Exploratory comparisons showed that (1) All children and ? 92.3% of the toddlers maintained serum bactericidal (rSBA) titers ? 1:8 at 15 mo post MenACWY-TT vaccination; statistically significantly higher rSBA geometric mean titers (GMTs) were observed compared with control vaccines. (2) At one month after polysaccharide challenge, all toddlers primed with MenACWY-TT or with the monovalent serogroup C conjugate vaccine had rSBA titers ? 1:8 and ? 1:128 for serogroup C and similar rSBA-GMTs; rSBA-GMTs for serogroups A, W-135 and Y were statistically significantly higher in toddlers primed with MenACWY-TT compared with the control vaccine. Thus, a single dose of MenACWY-TT induced persisting antibodies in toddlers and children and immune memory in toddlers. This study has been registered at www.clinicaltrials.gov NCT00126984.
Knuf, Markus; Baine, Yaela; Bianco, Veronique; Boutriau, Dominique; Miller, Jacqueline M.
It has been previously shown that one of the three meningococcal C conjugate (MCC) vaccines introduced in the United Kingdom proved highly immunogenic after the first dose of a three-dose schedule, with evidence of immune memory after dose 3. Thus, in infants a one- or two-dose schedule of this MCC vaccine, conjugated to tetanus toxoid (TT), may suffice. Healthy infants (n = 586) were randomized to receive either one (group 1), two (group 2), or three (group 3) doses of MCC-TT vaccine with a 10-?g polysaccharide booster given at 13 to 14 months of age. Serum bactericidal antibody (SBA) levels were measured by utilizing rabbit complement (rSBA), meningococcal C-specific immunoglobulin G (IgG), and avidity indices (AIs). For groups 1, 2, and 3, the percentages of infants with an rSBA level of ?8 against strain C11 were 98.4, 100, and 99.4%, respectively. Infants in group 1 with prevaccination rSBA titers of ?8 had post-primary MCC rSBA geometric mean titers (GMTs) significantly lower than those infants with prevaccination rSBA titers of <8. One dose of MCC-TT vaccine given to infants at 2 months of age yielded significantly lower SBA GMTs and geometric mean AIs (GMAIs) than two or three doses but elicited a significantly greater response after boosting, as reflected by rSBA levels and GMAI. This study provides the first evidence that the number of doses of MCC-TT used in infant immunization schedules could be decreased.
Borrow, Ray; Goldblatt, David; Finn, Adam; Southern, Joanna; Ashton, Lindsey; Andrews, Nick; Lal, Gouri; Riley, Christine; Rahim, Rukhsana; Cartwright, Keith; Allan, Geraldine; Miller, Elizabeth
Cross-linked dextran beads were used as a carrier for development of a ‘single-contact’ vaccine delivery system. Diphtheria toxoid (DT) was covalently coupled to dextran beads (DEX-DT conjugate). The conjugate was immunoreactive with antibodies raised against native DT. Immunization of rats with DEX-DT conjugate generated on average 24 times higher antibody titres against diphtheria toxoid than immunization with the conventional DT
M. Diwan; A. Misra; R. K. Khar; G. P. Talwar
...false Gonadotropin releasing factor analog-diphtheria toxoid conjugate...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL...1083 Gonadotropin releasing factor analog-diphtheria toxoid conjugate...mg) gonadotropin releasing factor analog-diphtheria toxoid...
Extensive use of meningococcal AC polysaccharide (MACP) vaccines has raised concerns about induction of immunologic hyporesponsiveness to C polysaccharide. We investigated the immunogenicity and safety of a meningococcal C-tetanus conjugate (MCC-TT) vaccine in naïve adults and prior MACP vaccinees. Laboratory staff (n = 113) were recruited; 73 were naïve to meningococcal vaccination, and 40 had previously received ?1 dose of MACP vaccine. Blood was taken prior to MCC-TT vaccination and 1 week, 1 month, and 6 months later. At each time point, proportions of subjects with serum bactericidal antibody (SBA) titers of ?8 or ?128 were similar (P > 0.46); >94% of subjects achieved titers of ?128 at 1 month. However, the geometric mean titer (GMT) of SBA at 1 month was higher in the naïve (1,757; 95% confidence interval [95% CI], 1,102 to 2,803) than in the previously vaccinated (662; 95% CI, 363 to 1,207) group (P = 0.02), and similarly at 6 months (P < 0.001). Conversely, geometric mean concentrations (GMCs) of serogroup C-specific immunoglobulin G (IgG) were significantly higher in the previously vaccinated group pre-MCC-TT and at 1 week; the groups were similar at 1 month, and there was some evidence that the GMC for the previously vaccinated group was higher at 6 months. Qualitative differences in antibodies between groups were demonstrated by using the SBA/IgG ratio, though avidity measures were similar for the two groups throughout the study. MCC-TT was well tolerated, with similar safety profiles in the two groups. Pain in the arm and headache were the most frequently reported events following vaccination. The study shows that MCC-TT is safe and immunogenic in naïve and previously MACP-vaccinated adults, though the magnitude and persistence of postvaccination SBA responses in the latter group were lower.
Southern, Jo; Deane, Sarah; Ashton, Lindsey; Borrow, Ray; Goldblatt, David; Andrews, Nick; Balmer, Paul; Morris, Rhonwen; Kroll, J. Simon; Miller, Elizabeth
An open-label randomized clinical trial of prophylactic paracetamol coadministered with 7-valent pneumococcal conjugate vaccine and hexavalent diphtheria toxoid, tetanus toxoid, 3-component acellular pertussis, hepatitis B, inactivated poliovirus, and Haemophilus influenzae type b vaccine
Background In two clinical trials, low-grade fever was observed more frequently after coadministration than after separate administration of two recommended routine pediatric vaccines. Since fever is an important issue with vaccine tolerability, we performed this open-label study on the efficacy and safety of prophylactic use of paracetamol (acetaminophen, Benuron®) in children administered routine 7-valent pneumococcal conjugate vaccine (PCV-7) coadministered with hexavalent vaccine (diphtheria-tetanus-acellular pertussis-hepatitis B, poliovirus, Haemophilus influenzae type b vaccine [DTPa-HBV-IPV/Hib]) in Germany. Methods Healthy infants (N?=?301) who received a 3-dose infant series of PCV-7 and DTPa-HBV-IPV/Hib plus a toddler dose were randomly assigned 1:1 to prophylactic paracetamol (125 mg or 250 mg suppositories, based on body weight) at vaccination, and at 6–8 hour intervals thereafter, or a control group that received no paracetamol. Rectal temperature and local and other systemic reactions were measured for 4 days post vaccination; adverse events were collected throughout the study. Results In the intent-to-treat population, paracetamol reduced the incidence of fever ?38°C, but this reduction was only significant for the infant series, with computed efficacy of 43.0% (95% confidence interval [CI]: 17.4, 61.2), and not significant after the toddler dose (efficacy 15.9%; 95% CI: ?19.9, 41.3); results were similar in the per protocol (PP) population. Fever >39°C was rare during the infant series, such that there were too few cases for assessment. After the toddler dose, paracetamol effectively reduced fever >39°C, reaching statistical significance in the PP population only (efficacy 79%; 95% CI: 3.9, 97.7). Paracetamol also reduced reactogenicity, but there were few significant differences between groups after any dose. No vaccine-related serious adverse events were reported. Conclusions Paracetamol effectively prevented fever and other reactions, mainly during the infant series. However, as events were generally mild and of no concern in either group our data support current recommendations to administer paracetamol to treat symptoms only and not for routine prophylaxis. Trial registration NCT00294294
A randomized study to assess the immunogenicity, antibody persistence and safety of a tetravalent meningococcal serogroups A, C, W-135 and Y tetanus toxoid conjugate vaccine in children aged 2-10 years
Incidence of meningococcal diseases is high in children, and effective vaccines are needed for this age group. In this phase II, open, controlled study, 309 children aged 2–10 y from Finland were randomized (3:1) into two parallel groups to receive one dose of meningococcal ACWY-tetanus toxoid conjugate vaccine (ACWY-TT group; n = 231) or a licensed meningococcal ACWY polysaccharide vaccine (Men-PS group; n = 78). Serum bactericidal activity using rabbit complement (rSBA) was evaluated up to three years post-vaccination. Exploratory comparisons suggested that rSBA vaccine response rates and geometric mean titers (GMTs) for each serogroup at one month post-vaccination and rSBA GMTs for serogroups A, W-135 and Y up to three years post-vaccination were higher in the ACWY-TT compared with Men-PS group, but did not detect any difference between groups in terms of rSBA-MenC GMTs at three years post-vaccination; this is explained by the higher proportion of children from the Men-PS group who were excluded because they were re-vaccinated with a monovalent meningococcal serogroup C vaccine due to loss of protective antibody levels against this serogroup. Although there was a higher incidence of local reactogenicity in the ACWY-TT group, general and unsolicited symptoms reporting rates were comparable in both groups. This study showed that MenACWY-TT was immunogenic with a clinically acceptable safety profile in children aged 2–10 y. MenACWY-TT induced higher functional antibody titers for all serogroups, which persisted longer for serogroups A, W-135 and Y, than the MenACWY polysaccharide vaccine. This study has been registered at www.clinicaltrials.gov NCT00427908.
Vesikari, Timo; Forsten, Aino; Boutriau, Dominique; Bianco, Veronique; Van der Wielen, Marie; Miller, Jacqueline M.
Randomized trial to assess the immunogenicity, safety and antibody persistence up to three years after a single dose of a tetravalent meningococcal serogroups A, C, W-135 and Y tetanus toxoid conjugate vaccine in toddlers
Effective vaccines offering broad protection to toddlers, who are at high risk for invasive meningococcal disease, are needed. Here, the immunogenicity, safety and antibody persistence of the tetravalent meningococcal ACWY tetanus toxoid conjugate vaccine (MenACWY-TT) were evaluated in toddlers. Healthy participants aged 12 to 23 mo (n = 304) were randomized (3:1) to receive one dose of MenACWY-TT or a monovalent meningococcal serogroup C conjugate vaccine (MenC-CRM197). Serum bactericidal activity was evaluated with assays using rabbit (rSBA) and human (hSBA) complement up to three years post-vaccination. MenACWY-TT was demonstrated to be non-inferior to MenC-CRM197 in terms of immunogenicity to serogroup C, and the pre-specified immunogenicity criteria for serogroups A, W-135 and Y were met. Exploratory analyses suggested that rSBA geometric mean titers (GMTs), hSBA GMTs and proportions of toddlers with rSBA titers ? 1:128 and hSBA titers ? 1:4 and ? 1:8 were higher for all serogroups at one month post-vaccination with MenACWY-TT compared with MenC-CRM197. At three years post-vaccination, at least 90.8% and 73.6% of MenACWY-TT recipients retained rSBA titers ? 1:8 for all serogroups and hSBA titers ? 1:4 for serogroups C, W-135 and Y, respectively, but the percentages of toddlers with hSBA titers ? 1:4 for serogroup A decreased to 21.8%. In both groups, grade 3 adverse events were infrequently reported and no serious adverse events were considered causally related to vaccination. These results suggest that one single dose of MenACWY-TT induces a robust and persistent immune response and has an acceptable safety profile in toddlers. This study has been registered at www.clinicaltrials.gov NCT00427908.
Vesikari, Timo; Forsten, Aino; Boutriau, Dominique; Bianco, Veronique; Van der Wielen, Marie; Miller, Jacqueline M.
Evaluation of De-O-Acetylated Meningococcal C Polysaccharide-Tetanus Toxoid Conjugate Vaccine in Infancy: Reactogenicity, Immunogenicity, Immunologic Priming, and Bactericidal Activity against O-Acetylated and De-O-Acetylated Serogroup C Strains
The polysaccharide capsule of serogroup C Neisseria meningitidis (MenC) has been integral to vaccine development. Licensed MenC vaccines contain the O-acetylated (OAc+) form of polysaccharide. Some MenC strains have de-O-acetylated (OAc?) polysaccharide, which may affect antibody specificity and functional activity when used in a vaccine. We evaluated an OAc-MenC conjugate-tetanus toxoid conjugate (MCC-TT) vaccine given concomitantly with whole-cell diphtheria-tetanus-pertussis, Haemophilus influenzae type b, and oral polio immunization in 83 infants at 2, 3, and 4 months of age. Serum bactericidal activities (SBA) against OAc+ and OAc? MenC strains and OAc+ and OAc? polysaccharide-specific immunoglobulin G (IgG) levels were evaluated. MCC-TT vaccine was well tolerated. All infants produced SBA titers of ?8 after a single dose at 2 months of age. The SBA geometric mean titer for OAc+ strain C11 increased from 2.7 (95% confidence interval [CI] 2.2 to 3.2) to 320 (95% CI, 237 to 432), 773 (95% CI, 609 to 982), and 1,063 (95% CI, 856 to 1319) after one, two, and three doses of MCC-TT, respectively. OAc? IgG levels were twice as high as OAc+ IgG levels after the primary series of MCC-TT vaccine, and the SBA was significantly higher against the OAc? MenC strain. Antibody responses to booster vaccination with either OAc+ MenC polysaccharide vaccine (MACP) or a fourth dose of MCC-TT at 14 months of age provided evidence of immunologic memory. The acetylation status of the booster vaccine influenced the specificity of the response, with significantly higher OAc? IgG levels and SBA after MCC-TT vaccine compared to MACP vaccine but similar OAc+ antibody levels. MCC-TT vaccine is highly immunogenic and primes for immunologic memory against OAc+ and OAc? MenC strains in infancy.
Richmond, Peter; Borrow, Ray; Findlow, Jamie; Martin, Sarah; Thornton, Carol; Cartwright, Keith; Miller, Elizabeth
Preparation, immunogenicity, and protective efficacy, in a murine model, of a conjugate vaccine composed of the polysaccharide moiety of the lipopolysaccharide of Vibrio cholerae O139 bound to tetanus toxoid.
The epidemic and pandemic potential of Vibrio cholerae O139 is such that a vaccine against this newly emerged serogroup of V. cholerae is required. A conjugate made of the polysaccharide moiety (O-specific polysaccharide plus core) of the lipopolysaccharide (LPS) of V. cholerae O139 (pmLPS) was prepared by derivatization of the pmLPS with adipic acid dihydrazide and coupling to tetanus toxoid (TT) by carbodiimide-mediated condensation. The immunologic properties of the conjugate were tested using BALB/c mice injected subcutaneously three times at 2 weeks interval and then a fourth time 4 weeks later. Mice were bled 7 days after each injection and then once each month for the following 6 months. LPS and TT antibody levels were determined by enzyme-linked immunosorbent assay using immunoplates coated with either O139 LPS or TT. Both pmLPS and pmLPS-TT conjugate elicited low levels of immunoglobulin M (IgM), peaking 5 weeks after the first immunization. The conjugate elicited high levels of IgG antibodies, peaking 3 months after the first immunization and declining slowly during the following 5 months. TT alone, or as a component of conjugate, induced mostly IgG antibodies. Antibodies elicited by the conjugate recognized both capsular polysaccharide and LPS from V. cholerae O139 and were vibriocidal. They were also protective in the neonatal mouse model of cholera infection. The conjugation of the O139 pmLPS, therefore, enhanced its immunogenicity and conferred T-dependent properties to this polysaccharide. PMID:11292781
Boutonnier, A; Villeneuve, S; Nato, F; Dassy, B; Fournier, J M
Lipooligosaccharides (LOS) isolated from Bordetella pertussis strains 186 and 606 were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-resolution magic angle spinning nuclear magnetic resonsnace (NMR). These analyses distinguished between the LOS of strains 186 and 606, suggesting that the structure of LOS in B. pertussis is heterogeneous. The pentasaccharide was selectively cleaved from LOS of B. pertussis strain 186, purified, and covalently linked to a monomer fraction of tetanus toxoid. Injection of rabbits with the neoglycoconjugate emulsified in complete Freund's adjuvant yielded immunoglobulin G antibodies that were reactive with the LOS. These antibodies reacted strongly with B. pertussis LOS possessing the complete dodecasaccharide, as determined by an enzyme-linked immunosorbent assay, immunoblotting, and flow cytometry with intact, live bacterial cells. The binding epitope within the pentasaccharide was investigated by saturation transfer difference (STD) NMR spectroscopy. Protons H-1 and H-4 of the terminal ?-d-GlcpNAc and proton H-6 and protons of an N-methyl group at H-4 of 3-substituted ?-l-FucpNAc4NMe exhibited the largest saturation transfers. STD NMR experiments confirmed that the immunodominant epitope recognized by the antineoglycoconjugate antibodies is located predominantly in the distal trisaccharide of B. pertussis 186 LOS. The antipentasaccharide antibodies induced by the conjugate inhibited the secretion of tumor necrosis factor alpha, interleukin-6, and NO by LOS-stimulated J774A.1 cells.
Niedziela, Tomasz; Letowska, Iwona; Lukasiewicz, Jolanta; Kaszowska, Marta; Czarnecka, Anna; Kenne, Lennart; Lugowski, Czeslaw
Three cases of angiolymphoid hyperplasia with eosinophilia are reported at the site of tetanus toxoid vaccination. All presented as nodules on the upper arm, a known adverse effect of the vaccine following superficial inoculation. Histologically the nodules showed numerous small and medium sized vessels, some lined by hyperplastic endothelial cells with perivascular lymphocytic cuffing and an inflammatory infiltrate of plasma cells, eosinophils and scattered mast cells. Lymphoid follicles replete with germinal centres were identified in the dermis and subcutaneous tissue. Immunostaining revealed a polytypic lymphoplasmacytic infiltrate and a curious IgE reticulated pattern within the germinal centres, a feature described in both Kimura's disease and angiolymphoid hyperplasia. The present study suggests that atopic reaction to tetanus toxoid may be an aetiological factor in some cases of angiolymphoid hyperplasia. PMID:2376400
Akosa, A B; Ali, M H; Khoo, C T; Evans, D M
Although captive elephants are commonly vaccinated annually against tetanus using commercially available tetanus toxoid vaccines marketed for use in horses and livestock, no data exists to prove that tetanus toxoid vaccination produces measurable antibody titers in elephants. An ELISA test was created to measure antibody responses to tetanus toxoid vaccinations in 22 Asian elephants ranging in age from 24 to 56 years (mean age 39 years) over a 7-month period. All animals had been previously vaccinated with tetanus toxoid vaccine, with the last booster administered 4 years before the start of the study. The great majority of elephants had titers prior to booster vaccination, and following revaccination all elephants demonstrated anamnestic increases in titers, indicating that this species does respond to tetanus vaccination. Surprisingly older animals mounted a significantly higher response to revaccination than did younger animals. PMID:19720403
Lindsay, William A; Wiedner, Ellen; Isaza, Ramiro; Townsend, Hugh G G; Boleslawski, Maria; Lunn, D P
Chronic infection with Pseudomonas aeruginosa is the main proven perpetrator of lung function decline and ultimate mortality in cystic fibrosis (CF) patients. Mucoid strains of this bacterium elaborate mucoid exopolysaccharide, also referred to as alginate. Alginate-based immunization of naïve animals elicits opsonic antibodies and leads to clearance of mucoid P. aeruginosa from the lungs. Alginate was isolated from mucoid P. aeruginosa strain 8821M by repeated ethanol precipitation, dialysis, proteinase and nuclease digestion, and chromatography. To improve immunogenicity, the purified antigen was coupled to tetanus toxoid (TT) with adipic acid dihydrazide (ADH) as a spacer and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDAC) as a linker. The reaction mixture was passed through a Sepharose CL-4B column. The resulting conjugate was composed of TT and large-size alginate polymer at a ratio of about 3 : 1; it was non-toxic and non-pyrogenic, and elicited high titres of alginate-specific IgG. Antisera raised against the conjugate had high opsonic activity against the vaccine strain. The alginate conjugate was also able to protect mice against a lethal dose of mucoid P. aeruginosa. These data indicate that an alginate-based vaccine has significant potential to protect against chronic infection with mucoid P. aeruginosa in the CF host. PMID:17005795
Kashef, Nasim; Behzadian-Nejad, Qorban; Najar-Peerayeh, Shahin; Mousavi-Hosseini, Kamran; Moazzeni, Mohammad; Djavid, Gholamreza Esmaeeli
Bacterial polysaccharide–protein conjugate vaccines (Haemophilus influenzae type b [Hib], pneumococcal and meningococcal conjugates) have revolutionized pediatric vaccination strategies. The widely used carrier proteins are tetanus toxoid (TT), diphtheria toxoid (DT) and diphtheria toxoid variant CRM197 protein, DT conjugates being in general less immunogenic. Multivalent conjugates using TT were found to be at risk for reduced polysaccharide responses, whilst multivalent CRM197
Ron Dagan; Jan Poolman; Claire-Anne Siegrist
Typhoid fever, caused by Salmonella enterica serovar Typhi (S. Typhi), is a major health problem particularly in developing countries. The available vaccines have certain limitations regarding their efficacy, and inability to induce an immune response especially in individuals under 2 years of age. Conjugate vaccines which consist of a bacteria-specific polysaccharide chemically bound to a carrier protein overcome these problems by inducing a T-cell dependent immune response characterized by enhanced immunogenicity in all ages. In this study, O-specific polysaccharides (OSP) of S. Typhi were conjugated to diphtheria toxoid (DT) using adipic acid dihydrazide (ADH) as a linker. These conjugates (OSP-AH-DT) were then evaluated for their immunogenicity using mice as a model and showed significantly higher levels of IgG ELISA titers (P = 0.0241 and 0.0245) than lipopolysaccharides alone. Different immunization schedules were compared and it was found that schedule-B (three injections with 4-weeks interval) induced higher immune responses than schedule-A (three injections with 2-weeks interval). We showed that diphtheria toxoid can be successfully employed as a carrier protein for conjugation with Salmonella OSP and play an important role in facilitating adequate immune response. PMID:22426380
Ali, Aamir; An, So Jung; Cui, Changfa; Haque, Abdul; Carbis, Rodney
Clostridium difficile is a major cause of nosocomial diarrhea in industrialized countries. Although most illnesses respond to available therapy, infection can increase morbidity, prolong hospitalization, and produce life-threatening colitis. Vaccines are being explored as an alternative means for protecting high-risk individuals. We assessed the safety, immunogenicity, and dose response of a parenteral vaccine containing C. difficile toxoids A and B. Thirty healthy adults were assigned to receive four spaced inoculations on days 1, 8, 30, and 60 with one of three doses of vaccine (6.25, 25, or 100 ?g). At each dose level, subjects were randomized, in a double-blind fashion, to receive either the soluble toxoids (n = 5) or toxoids adsorbed to alum (n = 5). Subjects were monitored for clinical and immunologic responses to vaccination. Vaccination was generally well tolerated, with occasional, usually mild, systemic reactions (abdominal pain, arthralgia, and diarrhea). The most common local reaction, mild arm pain, was reported by all recipients of the toxoid-alum formulation. Nearly all subjects (?90%) developed vigorous serum antibody responses to both toxins, as measured by immunoglobulin G (IgG) enzyme-linked immunosorbent assay and neutralization of cytotoxicity, whereas fecal IgA increases occurred in approximately 50%. Statistically significant effects of dose and formulation on immunogenicity were not seen, although antibody levels tended to be higher with the alum-adjuvanted formulations and with increasing doses of soluble toxoid. Serum antibody responses among the toxoid-alum group appeared to plateau at 25 ?g. We concluded that the C. difficile toxoid vaccine is safe and immunogenic in healthy volunteers. Further development as a prophylactic vaccine or for producing C. difficile hyperimmune globulin is justified.
Kotloff, Karen L.; Wasserman, Steven S.; Losonsky, Genevieve A.; Thomas, William; Nichols, Richard; Edelman, Robert; Bridwell, Margaret; Monath, Thomas P.
Preventing Tetanus, Diphtheria, and Pertussis Among Adolescents: Use of Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis Vaccines. Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Report, Vol. 55, No. RR-3, March 24, 2006.
During spring 2005, two tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Tdap) products formulated for use in adolescents (and, for one product, use in adults) were licensed in the United States (BOOSTRIX, GlaxoSmithKline Biologi...
Typhoid fever remains a serious public health problem in developing countries, especially among young children. Recent studies showed more than 50% of typhoid cases are in children under 5 years old. Licensed vaccines, such as Salmonella enterica serovar Typhi capsular Vi, did not confer protection against typhoid fever for this age group. Vi conjugate, prepared by binding Vi to Pseudomonas aeruginosa recombinant exoprotein A (rEPA), induces protective levels of antibody at as young as 2 years old. Because of the lack of regulatory precedent for rEPA in licensing vaccines, we employed diphtheria toxoid (DT) as the carrier protein to accommodate accessibility in developing countries. Five lots of Vi-DT conjugates were prepared using adipic acid dihydrazide (ADH) as the linker. All 5 lots showed consistency in their physical and chemical characteristics and final yields. These Vi-DT conjugates elicited levels of IgG anti-Vi in young mice significantly higher than those in mice injected with Vi alone and induced a booster response upon reinjection. This booster effect was absent if the Vi replaced one of the two conjugate injections. Vi-DT was stable under repeated freeze-thaw (20 cycles). We plan to perform clinical evaluation of the safety and immunogenicity of Vi-DT when added to the infant combination vaccines.
Cui, Changfa; Carbis, Rodney; An, So Jung; Jang, Hyun; Czerkinsky, Cecil; Szu, Shousun C.; Clemens, John D.
Typhoid fever remains a serious public health problem in developing countries, especially among young children. Recent studies showed more than 50% of typhoid cases are in children under 5 years old. Licensed vaccines, such as Salmonella enterica serovar Typhi capsular Vi, did not confer protection against typhoid fever for this age group. Vi conjugate, prepared by binding Vi to Pseudomonas aeruginosa recombinant exoprotein A (rEPA), induces protective levels of antibody at as young as 2 years old. Because of the lack of regulatory precedent for rEPA in licensing vaccines, we employed diphtheria toxoid (DT) as the carrier protein to accommodate accessibility in developing countries. Five lots of Vi-DT conjugates were prepared using adipic acid dihydrazide (ADH) as the linker. All 5 lots showed consistency in their physical and chemical characteristics and final yields. These Vi-DT conjugates elicited levels of IgG anti-Vi in young mice significantly higher than those in mice injected with Vi alone and induced a booster response upon reinjection. This booster effect was absent if the Vi replaced one of the two conjugate injections. Vi-DT was stable under repeated freeze-thaw (20 cycles). We plan to perform clinical evaluation of the safety and immunogenicity of Vi-DT when added to the infant combination vaccines. PMID:19889941
Cui, Changfa; Carbis, Rodney; An, So Jung; Jang, Hyun; Czerkinsky, Cecil; Szu, Shousun C; Clemens, John D
The polysaccharide (PS) derived from K. pneumoniae NCTC 5055 lipopolysaccharide (LPS) was covalently linked to tetanus toxoid by using carbodimide with adipic acid dihydrazide as a spacer molecule. The conjugate was found to be non-toxic and non-pyrogenic at 100 microg dose level. At a similar dose, the conjugate did not elicit any local skin reaction on intradermal preparatory injection in rabbits. The conjugate was immunoprotective as was evident from the decrease in relative colonization of bacteria in lungs of immunized rats as compared to the control animals. Immunization with the conjugate resulted in alveolar macrophage activation in terms of their ability to phagocytose bacteria in vitro. PMID:15691064
Chhibber, S; Rani, Mamta; Vanashree, Yadav
Intranasal or intramuscular (i.m.) immunization of mice and i.m. immunization of rabbits with formalinized staphylococcal enterotoxin B (SEB) toxoid in saline elicited higher anti-SEB serum immunoglobulin G (IgG) titers when the toxoid was formulated with proteosomes. In addition, intranasal immunization of mice with this proteosome-toxoid vaccine elicited high levels of anti-SEB IgA in lung and intestinal secretions, whereas the toxoid without proteosomes did not. Two i.m. immunizations with proteosome-toxoid plus alum also induced higher murine serum responses than alum-adjuvanted toxoid without proteosomes. Furthermore, proteosome-toxoid delivered intranasally in saline or i.m. with either saline or alum afforded significant protection against lethal SEB challenge in two D-galactosamine-sensitized murine models of SEB intoxication, i.e., the previously described i.m. challenge model and a new respiratory challenge model of mucosal SEB exposure. Efficacy correlated with the induction of high serum levels of anti-SEB IgG. In contrast, intranasal or i.m. immunization with toxoid in saline without proteosomes was not significantly protective in either challenge model. Proteosome-toxoid plus alum given i.m. also elicited more significant protection against respiratory challenge than the alum-adjuvanted toxoid alone. The capacity of proteosomes to enhance both i.m. and intranasal immunogenicity and efficacy of SEB toxoid indicates that testing such proteosome-SEB toxoid vaccines in the nonhuman primate aerosol challenge model of SEB intoxication prior to immunogenicity trials in humans is warranted. These data expand the applicability of the proteosome mucosal vaccine delivery system to protein toxoids and suggest that respiratory delivery of proteosome vaccines may be practical for enhancement of both mucosal and systemic immunity against toxic or infectious diseases.
Lowell, G H; Kaminski, R W; Grate, S; Hunt, R E; Charney, C; Zimmer, S; Colleton, C
An investigational tetravalent meningococcal serogroups A, C, W-135 and Y-tetanus toxoid conjugate vaccine co-administered with Infanrix™ hexa is immunogenic, with an acceptable safety profile in 12-23-month-old children.
Tetravalent meningococcal serogroups ACWY conjugate vaccines will provide an advantage to those at most risk of invasive meningococcal disease; namely young children. Co-administration of ACWY-TT with DTaP-HBV-IPV/Hib was assessed in a randomized trial in 793 children aged 12-23 months. Pre-specified criteria for non-inferiority of immunogenicity following co-administration versus separate ACWY-TT and DTaP-HBV-IPV/Hib administration were reached. One month post-vaccination, ? 97.3% of ACWY-TT vaccinees had rSBA titres ? 1:8 (all serogroups). Seroprotection/seropositivity rates against DTaP-HBV-IPV/Hib antigens were ? 98.2%. The safety profile of co-administration was similar to that of DTaP-HBV-IPV/Hib alone. ACWY-TT and DTaP-HBV-IPV/Hib co-administration during the second year would facilitate introduction of ACWY-TT into routine toddler vaccination schedules. PMID:21420417
Knuf, Markus; Pantazi-Chatzikonstantinou, Anna; Pfletschinger, Ulrich; Tichmann-Schumann, Irmingard; Maurer, Hartwig; Maurer, Lothar; Fischbach, Thomas; Zinke, Henrike; Pankow-Culot, Heidemarie; Papaevangelou, Vassiliki; Bianco, Veronique; Van der Wielen, Marie; Miller, Jacqueline M
Phase I/II, Open-Label Trial of Safety and Immunogenicity of Meningococcal (Groups A, C, Y, and W-135) Polysaccharide Diphtheria Toxoid Conjugate Vaccine in Human Immunodeficiency Virus-Infected Adolescents
Background: Quadrivalent meningococcal polysaccharide conjugate vaccine (MCV4) is routinely recommended for healthy youth in the United States, but there are no data about its use in HIV-infected people. Methods: P1065 is a Phase I/II trial of MCV4 safety and immunogenicity in HIV-infected children and youth performed at 27 US sites of the IMPAACT network. All youth (11–24 years old) received 1 dose of open-label MCV4 at entry. Standardized questionnaires were used to evaluate safety. Baseline protective immunity was defined as rabbit serum bactericidal antibody (rSBA) titer ?1:128. Immunogenic response was defined as a ?4-fold rise in rSBA against each meningococcal serogroup. Multivariable logistic regression analysis was used to evaluate the association of demographic and clinical characteristics on immunogenic response to serogroup C. Results: Among 319 subjects who received MCV4, 10 (3.1%) reported immediate adverse events which were local and mild, and 7 (2.2%) experienced Grade ?3 adverse events, unrelated to vaccine. The 305 subjects with serologic data had a median age of 17 years and were 59% male, 50% Black, and 38% Latino. Subjects were stratified by entry CD4%: 12%, CD4 <15%; 40%, 15% to 24%; and 48%, ?25%. Baseline protective immunity varied by serogroup: A, 41%; C, 11%; W-135, 15%; Y, 35% The immunogenic response rates to serogroups A, C, W-135, and Y were 68%, 52%, 73%, and 63%, respectively. In multivariable logistic regression models, lower entry CD4%, higher entry viral load, and CDC Class B/C diagnosis were associated with significantly lower odds of response to serogroup C. Conclusion: Many HIV-infected youth naturally acquire meningococcal immunity. MCV4 is safe and immunogenic in HIV-infected youth, but response rates are lower than in healthy youth, particularly for those with more advanced HIV clinical, immunologic, and virologic status.
Siberry, George K.; Williams, Paige L.; Lujan-Zilbermann, Jorge; Warshaw, Meredith G.; Spector, Stephen A.; Decker, Michael D.; Heckman, Barbara E.; Demske, Emily F.; Read, Jennifer S.; Jean-Philippe, Patrick; Kabat, William; Nachman, Sharon
Tetanus toxoid (TT) was assessed as a positive marker for avian influenza (AI) virus vaccination in chickens, in a vaccination and challenge study. Chickens were vaccinated twice with inactivated AI H5N2 virus vaccine, and then challenged three weeks later with highly pathogenic AI H5N1 virus. Vaccinated chickens were compared with other groups that were either sham-vaccinated or vaccinated with virus
C. M. James-Berry; D. Middleton; J. P. Mansfield; S. G. Fenwick; T. M. Ellis
Mice vaccinated with a combination of two Staphylococcus aureus antigens consisting of a recombinant collagen-binding protein (CnBP) and alpha-toxoid (alpha-toxoid) were significantly protected from intramammary challenge infection with S. aureus. The average number of bacteria recovered from the glands of mice vaccinated with the combination of CnBP/alpha-toxoid was significantly lower compared to the average number of bacteria recovered from the glands of mice vaccinated with only CnBP or alpha-toxoid or controls (P< or =0.01). Histopathological examination of mammary glands of mice vaccinated with CnBP together with alpha-toxoid showed no pathological changes, whereas glands of mice vaccinated with CnBP or alpha-toxoid alone developed severe mastitis and showed both focal and disseminated necrosis. PMID:10888356
Mamo, W; Fröman, G; Müller, H P
The Tat protein is essential for HIV type 1 (HIV-1) replication and may be an important virulence factor in vivo. We studied the role of Tat in viral pathogenesis by immunizing rhesus macaques with chemically inactivated Tat toxoid and challenging these animals by intrarectal inoculation with the simian/human immunodeficiency virus 89.6PD. Immune animals had significantly attenuated disease with lowered viral RNA, interferon-?, and chemokine receptor expression (CXCR4 and CCR5) on CD4+ T cells; these features of infection have been linked to in vitro effects of Tat and respond similarly to extracellular Tat protein produced during infection. Immunization with Tat toxoid inhibits key steps in viral pathogenesis and should be included in therapeutic or preventive HIV-1 vaccines.
Pauza, C. David; Trivedi, Parul; Wallace, Marianne; Ruckwardt, Tracy J.; Le Buanec, Helene; Lu, Wei; Bizzini, Bernard; Burny, Arsene; Zagury, Daniel; Gallo, Robert C.
Streptococcus pneumoniae is a serious Gram-positive pathogen responsible for several life-threatening pneumococcal diseases. Pneumococcal capsular polysaccharide (CPS) is a key virulence determinant of S. pneumoniae and its immunogenicity can be improved by conjugation with a carrier protein. Reductive amination, the most widely used approach for pneumococcal CPS conjugate vaccine (PCV), suffers from low conjugation efficiency and the problem of steric hindrance. Here, copper-catalyzed azide-alkyne cycloaddition was used for development of PCV with long spacer arm (L-PCV). Tetanus toxoid (TT) was used as the carrier protein. The long spacer arm in L-PCV can minimize the problem of steric hindrance between CPS and TT, thereby improving the CPS-specific antibody titers in the mice model. L-PCV can also induce high avidity functional antibody and elicit immunological memory in response to the native CPS. PMID:24120485
Wu, Dinglong; Ji, Shaoyang; Hu, Tao
SEP toxoid-containing microspheres were tested for efficacy in rhesus monkeys as a vaccine candidate for respiratory SEP toxicosis and toxic shock. Forty monkeys were randomly separated into 10 groups of four monkeys: 9 groups were vaccinated with the mic...
J. Tseng J. L. Komisar R. N. Trout R. E. Hunt J. Y. Chen
New Zealand White (NZW) rabbits were immunized with several different nontoxic botulinum neurotoxin serotype B (BoNT/B) preparations in an effort to optimize the production of a rapid and highly potent, effective neutralizing antibody response. The immunogens included a recombinant heavy chain (rHc) protein produced in Escherichia coli, a commercially available formaldehyde-inactivated toxoid, and an alkylated toxoid produced by urea-iodoacetamide inactivation of the purified active toxin. All three immunogens elicited an antibody response to BoNT/B, detected by enzyme-linked immunosorbent assay (ELISA) and by toxin neutralization assay, by the use of two distinct mouse toxin challenge models. The induction period and the ultimate potency of the observed immune response varied for each immunogen, and the ELISA titer was not reliably predictive of the potency of toxin neutralization. The kinetics of the BoNT/B-specific binding immune response were nearly identical for the formaldehyde toxoid and alkylated toxoid immunogens, but immunization with the alkylated toxoid generated an approximately 10-fold higher neutralization potency that endured throughout the study, and after just 49 days, each milliliter of serum was capable of neutralizing 107 50% lethal doses of the toxin. Overall, the immunization of rabbits with alkylated BoNT/B toxoid appears to have induced a neutralizing immune response more rapid and more potent than the responses generated by vaccination with formaldehyde toxoid or rHc preparations.
Held, Daniel M.; Shurtleff, Amy C.; Fields, Scott; Green, Christopher; Fong, Julie; Jones, Russell G. A.; Sesardic, Dorothea; Buelow, Roland; Burke, Rae Lyn
Vaccine development against Group B Neisseria meningitidis is complicated by the nature of the capsular polysaccharide, which is ? 2-8-linked poly-sialic acid, identical in structure to the poly-sialic acid found in many mammalian tissues during development. To test the feasibility of a vaccine based on this polysaccharide, we synthesized several conjugates of meningococcal B polysaccharide linked to a carrier protein
Antonella Bartoloni; Francesco Norelli; Costante Ceccarini; Rino Rappuoli; Paolo Costantino
The effect of acetaminophen on reducing the frequency and severity of adverse reactions following diphtheria-pertussis-tetanus toxoids-polio vaccine was studied in a randomized clinical trial involving 519 vaccinations in 383 infants 2 to 6 months of age and 70 infants 18 months of age. Significantly fewer local and systemic reactions were reported in acetaminophen-treated infants at 2 to 6 months of age. Acetaminophen also reduced the incidence of fever greater than 38.0 degrees C from 44% to 27%. Only 0.9% of acetaminophen-treated infants had overall behavioral changes rated as severe by parents compared to 13% of the placebo group. Infants vaccinated at 18 months of age had higher rates of systemic and local reactions than younger infants. Acetaminophen did not result in significant reductions in reaction rates after the booster at 18 months. We conclude that acetaminophen administered at the time of primary vaccination with diphtheria-pertussis-tetanus toxoids-polio can significantly reduce the frequency and severity of common adverse reactions. PMID:3313232
Ipp, M M; Gold, R; Greenberg, S; Goldbach, M; Kupfert, B B; Lloyd, D D; Maresky, D C; Saunders, N; Wise, S A
Our research on pathogenesis of disseminated candidiasis led to the discovery that antibodies specific for Candida albicans cell surface ?-1, 2–mannotriose [?-(Man)3] protect mice. A 14 mer peptide Fba, which derived from the N-terminal portion of the C. albicans cytosolic/cell surface protein fructose-bisphosphate aldolase, was used as the glycan carrier and resulted in a novel synthetic glycopeptide vaccine ?-(Man)3-Fba. By a dendritic cell-based immunization approach, this conjugate induced protective antibody responses against both the glycan and peptide parts of the vaccine. In this report, we modified the ?-(Man)3-Fba conjugate by coupling it to tetanus toxoid (TT) in order to improve immunogenicity and allow for use of an adjuvant suitable for human use. By new immunization procedures entirely compatible with human use, the modified ?-(Man)3-Fba-TT was administered either alone or as a mixture made with alum or monophosphoryl lipid A (MPL) adjuvants and given to mice by a subcutaneous (s.c.) route. Mice vaccinated with or, surprisingly, without adjuvant responded well by making robust antibody responses. The immunized groups showed a high degree of protection against a lethal challenge with C. albicans as evidenced by increased survival times and reduced kidney fungal burden as compared to control groups that received only adjuvant or DPBS buffer prior to challenge. To confirm that induced antibodies were protective, sera from mice immunized against the ?-(Man)3-Fba-TT conjugate transferred protection against disseminated candidiasis to naïve mice, whereas C. albicans-absorbed immune sera did not. Similar antibody responses and protection induced by the ?-(Man)3-Fba-TT vaccine was observed in inbred BALB/c and outbred Swiss Webster mice. We conclude that addition of TT to the glycopeptide conjugate results in a self-adjuvanting vaccine that promotes robust antibody responses without the need for additional adjuvant, which is novel and represents a major step forward in vaccine design against disseminated candidiasis.
Xin, Hong; Cartmell, Jonathan; Bailey, Justin J.; Dziadek, Sebastian; Bundle, David R.; Cutler, Jim E.
Conjugates of an uronic acid-containing capsular polysaccharide (CP), pneumococcous type 12F (Pn12F) bound to diphtheria toxoid (DT), were studied for safety and immunogenicity in adult volunteers. In mice, these conjugates, prepared with the same lot of DT and Pn12F-40234-006, a homogenous CP of high molecular weight, or Pn12-812408, a polydisperse CP with lower-molecular-weight material, were more immunogenic than the Pn12F alone and had T-cell dependent properties (A. Fattom, W. F. Vann, S.C. Szu, A. Sutton, X. Li, B. Bryla, G. Schiffman, J. B. Robbins, and R. Schneerson, Infect. Immun. 56:2292-2298, 1988). Adult volunteers, randomized into three groups, were injected either with one of these two conjugates or with Pnu-Imune, the 23 valent pneumococcus vaccine containing 25 micrograms of Pn12F as one of its components. Volunteers were injected two times, 4 weeks apart, with the Pn12F-DT conjugates and once with the Pnu-Imune. Side reactions following injection of the conjugates of Pnu-Imune were mild and short-lived. At 4 weeks and at 7 months after the first injection, higher levels of Pn12F antibodies were found in the volunteers injected with the conjugates than in the Pnu-Imune group (P less than 0.001). The conjugate prepared with the higher-molecular-weight Pn12F elicited higher levels of antibodies than the conjugate prepared with a lower-molecular-weight Pn12F preparation (P = 0.05). Both conjugates elicited about a 13-fold rise in DT antibodies.
Fattom, A; Lue, C; Szu, S C; Mestecky, J; Schiffman, G; Bryla, D; Vann, W F; Watson, D; Kimzey, L M; Robbins, J B
The Lowry method was used in this study to measure protein inHaemophilus influenzae type b (Hib) conjugate vaccines (polyribosylibitol phosphate-tetanus toxoid; PRP-TT) using deoxycholic acid (DOC) to induce\\u000a protein precipitation. Trichloroacetic acid (TCA) did not induce precipitation adequately from the Hib conjugate bulk and\\u000a the freeze-dried Hib conjugate product. Its yield was approximately 50%. The matrix structure of Hib conjugate
Hyun Sung Kim; Sang Joon Kim; Hui Jung Kim; Han Uk Kim; Sang Joem Ahn; Byung-Ki Hur
Suml'nary The molecular characteristics of the humoral immune response to a serotype A Cr~tococcus neoformans infection were compared with the response elicited by a cryptococcal ghicuronoxylomannan-tetanus toxoid (GXM-TT) conjugate. Anticryptococcal monoclonal antibodies (mAbs) isolated from both responses have previously been shown to recognize the same antigenic determinant of cryptococcal GXM. Southern blot and sequence analyses indicate that the hybridomas isolated
Jean Mukherjee; Arturo Casadeva; Matthew D. Scharff
Staphylococcal enterotoxin B (SEB) toxoid-containing microspheres were tested for efficacy in rhesus monkeys as a vaccine candidate for respiratory SEB toxicosis and toxic shock. Forty monkeys were randomly separated into 10 groups of four monkeys each: 9 groups were vaccinated with the microspheres via combi- nationsofmucosalandnonmucosalroutes,and1groupservedasnonvaccinatedcontrols.Bothvaccinatedand nonvaccinated monkeys were then challenged with a high lethal dose of SEB aerosol. Monkeys
JEENAN TSENG; JACK L. KOMISAR; RODNEY N. TROUT; ROBERT E. HUNT; JAMES YOK-JEN CHEN; ANTHONY J. JOHNSON; LOUISE PITT; ANDDAVID L. RUBLE
Pertussis is increasingly being recognized as an important cause of cough illness in adolescents and adults. To evaluate the safety and immunogenicity of an adult formulation of a five-component (pertussis toxoid, filamentous hemagglutinin, pertactin, fimbriae 2 and 3) acellular pertussis vaccine combined with diphtheria and tetanus toxoids, we randomly allocated 749 healthy adolescents and adults from 12–54 years of age
Scott A. Halperin; Bruce Smith; Margaret Russell; Paul Hasselback; Roland Guasparini; Danuta Skowronski; William Meekison; Robert Parker; Pierre Lavigne; Luis Barreto
Benzo[a]pyrene (B[a]P) is a small molecular weight carcinogen and the prototype of polycyclic aromatic hydrocarbons (PAHs). While these compounds are primarily known for their carcinogenicity, B[a]P and its metabolites are also neurotoxic for mammalian species. To develop a prophylactic immune strategy against detrimental effects of B[a]P, female Balb/c mice immunized with a B[a]P-diphtheria toxoid (B[a]P-DT) conjugate vaccine were sub-acutely exposed to 2mg/kg B[a]P and behavioral performances were monitored in tests related to learning and memory, anxiety and motor coordination. mRNA expression of the NMDA receptor (NR1, 2A and 2B subunits) involved in the above behavioral functions was measured in 5 brain regions. B[a]P induced NMDA1 expression in three (hippocampus, amygdala and cerebellum) of five brain regions investigated, and modulated NMDA2 in two of the five brain regions (frontal cortex and cerebellum). Each one of these B[a]P-effects was reversed in mice that were immunized against this PAH, with measurable consequences on behavior such as anxiety, short term learning and memory. Thus active immunization against B[a]P with a B[a]P-DT conjugate vaccine had a protective effect and attenuated the pharmacological and neurotoxic effects even of high concentrations of B[a]P. PMID:23684556
Schellenberger, Mario T; Grova, Nathalie; Farinelle, Sophie; Willième, Stéphanie; Schroeder, Henri; Muller, Claude P
Meningococcal conjugate vaccines have several advantages over polysaccharide vaccines, including the ability to induce greater antibody persistence, avidity, immunologic memory, and herd immunity. Since 1999, meningococcal conjugate vaccine programs have been established across the globe. Many of these vaccination programs have resulted in significant decline in meningococcal disease in several countries. Recent introduction of serogroup A conjugate vaccine in Africa offers the potential to eliminate meningococcal disease as a public health problem in Africa. However, the duration of immune response and the development of widespread herd immunity in the population remain important questions for meningococcal vaccine programs. Because of the unique epidemiology of meningococcal disease around the world, the optimal vaccination strategy for long-term disease prevention will vary by country.
Terranella, Andrew; Cohn, Amanda; Clark, Thomas
Meningococcal diseases are serious threats to global health, and new vaccines specifically tailored to meet the age-related needs of various geographical areas are required. This paper focuses on the meningococcal conjugate vaccines developed by GSK Biologicals. Two combined conjugate vaccines were developed to help protect infants and young children in countries where the incidence of meningococcal serogroup C or serogroup C and Y disease is important: Hib-MenC-TT vaccine, which offers protection against Haemophilus influenzae type b and Neisseria meningitidis serogroup C diseases, is approved in several countries; and Hib-MenCY-TT vaccine, which adds N. meningitidis serogroup Y antigen, is currently in the final stages of development. Additionally, a tetravalent conjugate vaccine (MenACWY-TT) designed to help protect against four meningococcal serogroups is presently being evaluated for global use in all age groups. All of these vaccines were shown to be highly immunogenic and to have clinically acceptable safety profiles.
Miller, Jacqueline M.; Mesaros, Narcisa; Van Der Wielen, Marie; Baine, Yaela
In September 1998, more than 800 young people in Jordan believed they had suffered from the side-effects of tetanus-diphtheria toxoid vaccine administered at school; 122 of them were admitted to hospital. For the vast majority, their symptoms did not result from the vaccine but arose from mass psychogenic illness. The role played by the media, the children's parents, and the medical profession in the escalation of this mass reaction appeared, at first sight, to be unusual and even unique to the circumstances in Jordan at the time. A review of the literature showed, however, that this mass reaction was similar in many ways to previous outbreaks, even though the underlying causes varied. There are about 200 published accounts of mass responses to situations involving suspected poisoning or other events. Because such mass reactions are relatively rare and the triggers so diverse, individuals faced with responding to them are unlikely to have prior experience in how to handle them and are unlikely to take bold steps to prevent their escalation. Indeed they may be unaware that such events have been recorded before. The lessons learned from this incident in Jordan may help other immunization programme managers to handle crisis situations elsewhere.
Kharabsheh, S.; Al-Otoum, H.; Clements, J.; Abbas, A.; Khuri-Bulos, N.; Belbesi, A.; Gaafar, T.; Dellepiane, N.
The Clostridium difficile toxins A and B are primarily responsible for symptoms of C. difficile associated disease and are prime targets for vaccine development. We describe a plasmid-based system for the production of genetically modified toxins in a non-sporulating strain of C. difficile that lacks the toxin genes tcdA and tcdB. TcdA and TcdB mutations targeting established glucosyltransferase cytotoxicity determinants were introduced into recombinant plasmids and episomally expressed toxin mutants purified from C. difficile transformants. TcdA and TcdB mutants lacking glucosyltransferase and autoproteolytic processing activities were ~10?000-fold less toxic to cultured human IMR-90 cells than corresponding recombinant or native toxins. However, both mutants retained residual cytotoxicity that could be prevented by preincubating the antigens with specific antibodies or by formalin treatment. Such non-toxic formalin-treated mutant antigens were immunogenic and protective in a hamster model of infection. The remaining toxicity of untreated TcdA and TcdB mutant antigens was associated with cellular swelling, a phenotype consistent with pore-induced membrane leakage. TcdB substitution mutations previously shown to block vesicular pore formation and toxin translocation substantially reduced residual toxicity. We discuss the implications of these results for the development of a C. difficile toxoid vaccine.
Flint, Mike; Kalyan, Narender; Johnson, Erik; Witko, Susan E.; Kotash, Cheryl; Zhao, Ping; Megati, Shakuntala; Yurgelonis, Irina; Lee, Phillip Kwok; Matsuka, Yury V.; Severina, Elena; Deatly, Anne; Sidhu, Mini; Jansen, Kathrin U.; Minton, Nigel P.; Anderson, Annaliesa S.
In order to plan for the wide-scale introduction of meningococcal C conjugate (MCC) vaccine for United Kingdom children up to 18 years old, phase II trials were undertaken to investigate whether there was any interaction between MCC vaccines conjugated to tetanus toxoid (TT) or a derivative of diphtheria toxin (CRM197) and diphtheria-tetanus vaccines given for boosting at school entry or leaving. Children (n = 1,766) received a diphtheria-tetanus booster either 1 month before, 1 month after, or concurrently with one of three MCC vaccines conjugated to CRM197 or TT. All of the MCC vaccines induced high antibody responses to the serogroup C polysaccharide that were indicative of protection. The immune response to the MCC-TT vaccine was reduced as a result of prior immunization with a tetanus-containing vaccine, but antibody levels were still well above the lower threshold for protection. Prior or simultaneous administration of a diphtheria-containing vaccine did not affect the response to MCC-CRM197 vaccines. The immune responses to the carrier proteins were similar to those induced by a comparable dose of diphtheria or tetanus vaccine. The results also demonstrate that, for these conjugate vaccines in these age groups, both standard enzyme-linked immunosorbent assays and those that measure high-avidity antibodies to meningococcal C polysaccharide correlated equally well with assays that measure serum bactericidal antibodies, the established serological correlate of protection for MCC vaccines.
Burrage, Moya; Robinson, Andrew; Borrow, Ray; Andrews, Nick; Southern, Joanna; Findlow, Jamie; Martin, Sarah; Thornton, Carol; Goldblatt, David; Corbel, Michael; Sesardic, Dorothea; Cartwight, Keith; Richmond, Peter; Miller, Elizabeth
The incidence of invasive diseases, including meningitis caused by Haemophilus influenzae type b (Hib) was markedly decreased after routine immunization of Hib vaccine through diverse schedules in many countries. The purpose of this study was to evaluate the immunogenicity and safety of Hib conjugate vaccines in Korean children before the implementation of a national immunization program against Hib in Korea. A multicenter controlled trial was performed on two different Hib vaccines in Korean children. A total of 319 infants were enrolled: 199 infants were immunized with the Hib polysaccharide conjugated to the tetanus toxoid (PRP-T) and 120 infants with the Hib polysaccharide conjugated to the outer-membrane protein of Neisseria meningitides (PRP-OMP). Immunogenicity was evaluated by enzyme-linked immunosorbent assay (ELISA) and serum bactericidal assay. Both vaccines showed good immunologic responses after primary immunization. After 2 doses of PRP-T or PRP-OMP, 78.9% and 91.7% of infants achieved an antibody level of ?1.0 µg/mL, respectively. Both vaccines were safe and well-tolerated. No serious adverse events were observed. Thus, Hib conjugate vaccines appear to be safe and show good immunogenicity in Korean infants. These results will be important reference data for the implementation of Hib vaccine in the national immunization program of Korea.
Lee, Hyunju; Chung, Eun Hee; Kang, Jin Han; Kim, Jong Hyun; Kim, Jung Soo; Lee, Hoan Jong; Oh, Sung Hee; Park, Eun Ae; Park, Su-Eun
Evaluation of components of X-ray irradiated 7-valent pneumococcal conjugate vaccine and pneumococcal vaccine polyvalent and X-ray and gamma-ray irradiated acellular pertussis component of DTaP vaccine products
Samples of pneumococcal vaccine polyvalent, 7-valent pneumococcal conjugate vaccine, and two different diphtheria and tetanus toxoids and acellular pertussis vaccines adsorbed were irradiated with X-rays and/or gamma-rays (Co-60). Mouse IgG and IgM antibody responses (ELISA) for types 9V, 14, 18C, and 19F pneumococcal polysaccharides and conjugates indicated that the polysaccharides were more tolerant of the radiation than the conjugates. The mouse antibody response for the detoxified pertussis toxin (PT) antigen, filamentous hemagglutinin antigen (FHA), pertactin (PRN), and fimbriae types 2 and 3 (FIM) antigens for the appropriate vaccine type indicated that the antibody response was not significantly changed in the 25 kGy X-ray irradiated vaccines frozen in liquid nitrogen compared to the control vaccine.
May, J. C.; Rey, L.; Lee, Chi-Jen; Arciniega, Juan
Serum antibodies to pertussis toxin (PT) have been shown to be protective against severe pertussis disease, although a specific level of anti-PT antibody that correlates with protection has not been demonstrated. Current animal models such as the intracerebral challenge model have significant limitations in correlating protection to a specific level of anti-PT antibody. This study examines the protective effects of priming with tetranitromethane-inactivated pertussis toxoid (PTx) vaccine in the aerosol challenge model and whether a measurable response to a priming dose of PTx is enough to initiate a protective secondary response when challenged with infection. The correlation of priming with markers of illness such as leukocytosis, weight loss, bacterial proliferation, and mortality after established infection with Bordetella pertussis was explored. BALB/c mice were immunized with PTx vaccine on day 6 of life and then challenged with B. pertussis using the aerosol challenge model. Data were analyzed according to the primary immunologic response, differentiating responders (anti-PT immunoglobulin G [IgG] > or =1 microg/ml) from nonresponders (anti-PT IgG <1 microg/ml). Mice that showed evidence of priming on the day of aerosol challenge were able to mount a secondary response to the challenge with a > or =2-fold rise in anti-PT IgG antibody by day 7 and a > or =10-fold rise by day 14 post-aerosol challenge. These primed mice were significantly better protected against leukocytosis, weight loss, and proliferation of B. pertussis in the lungs following aerosol challenge than the nonprimed group. This protection correlated with levels of anti-PT antibody in serum present on the day of aerosol challenge. PMID:12117973
Bruss, Jon B; Siber, George R
Tetanus is caused by a neurotoxin produced by Clostridium tetani (C. tetani), a spore-forming bacterium. Infection begins when tetanus spores are introduced into damaged tissue. Tetanus is characterized by muscle rigidity and painful muscle spasms caused by tetanus toxin's blockade of inhibitory neurons that normally oppose and modulate the action of excitatory motor neurons. Maternal and neonatal tetanus (MNT) are caused by unhygienic methods of delivery, abortion, or umbilical-cord care. Maternal and neonatal tetanus are both forms of generalized tetanus and have similar clinical courses. About 90% of neonates with tetanus develop symptoms in the first 3-14 d of life, mostly on days 6-8, distinguishing neonatal tetanus from other causes of neonatal mortality which typically occur during the first two days of life. Overall case fatality rates for patients admitted to the hospital with neonatal tetanus in developing countries are 8-50%, while the fatality rate can be as high as 100% without hospital care. Tetanus toxoid (TT) vaccination of pregnant women to prevent neonatal tetanus was included in WHO's Expanded Program on Immunization (EPI) a few years after its inception in 1974. In 2000, WHO, UNICEF, and UNFPA formed a partnership to relaunch efforts toward this goal, adding the elimination of maternal tetanus as a program objective, and setting a new target date of 2005. By February 2007, 40 countries had implemented tetanus vaccination campaigns in high-risk areas, targeting more than 94 million women, and protecting more than 70 million subjects with at least two doses of TT. In 2011, 653 NT cases were reported in India compared with 9313 in 1990. As of February 2012, 25 countries and 15 States and Union Territories of India, all of Ethiopia except Somaliland, and almost 29 of 34 provinces in Indonesia have been validated to have eliminated MNT. PMID:22894950
Verma, Ramesh; Khanna, Pardeep
Active mouse protection test (AMPT) and enzyme linked immunosorbent assay (ELISA) were used to determine the immunogenicity of whole cell typhoid vaccine when administered in conjunction with either tetanus toxoid (TT) or DEAE-Dextran (DD). Immunization of mice with whole cell typhoid vaccine showed enhanced potency either when administered in conjunction with TT or DD and values were statistically significant (p < 0.05) in comparison to conventional or standard typhoid vaccines. For ELISA, the mice were immunized with 2 different schedules, one in which a single dose of 0.25 ml subcutaneously (s/c) was administered and in another two doses of 0.25 ml each s/c, 14 days apart. In case of single dose schedule of immunization D vaccine (Whole cell typhoid + 5 mg/ml DD) showed significant increase of immune response (3.201 log10) as compared to plain vaccine (2.550 log10). Two dose schedule further increased the titres to 3.856 log10. DD adjuvanted vaccine showed higher potency by AMPT as compared to the TT adjuvanted vaccine or plain vaccine. The present study clearly demonstrates that a single dose of 0.25 ml which is equivalent to half of the conventionally used single human dose of typhoid vaccine adjuvanted with DD can significantly improve the immunogenicity of the vaccine. PMID:9009480
Kaistha, J; Sokhey, J; Singh, S; Kumar, S; John, P C; Sharma, N C
A collaborative study on the evaluation of an alternative functional assay, the Vero cell method, to the Ph. Eur. in vivo challenge procedures for potency determination of diphtheria toxoid in 6 different combined vaccines was initiated in January 2001. The study was an extension of a previous study for the validation of serological methods for potency testing of tetanus toxoid vaccines for human use. To allow interim evaluation of test results and to monitor study progress, the project was divided into three consecutive phases. The results of Phase I and II studies are presented in this report. Pre-validation (Phase I) study, performed in two laboratories, indicated that comparable diphtheria potency estimates were obtained in the Ph. Eur. direct intradermal challenge assay in guinea pigs, in Vero cell assay and in indirect ELISA for five vaccines of different potencies (range of estimates: ca. 20-200 IU/ml). The correlation coefficients between the challenge assay and the Vero cell assay corresponded to those between the challenge assay and ELISA, confirming that the antibodies play an important role in protection and that predominantly protective/neutralising antibodies are present in guinea pigs, at the time point investigated. It was observed, for Vero cell assays, that about 16-35 (9-28 in Phase II study) fold lower titre of individual serum samples were obtained when using equine, rather than guinea pig reference serum. The study also provided preliminary information that sera from the same guinea pigs may be used for potency determination of both diphtheria and tetanus toxoid components of vaccines. In Phase II, another five laboratories analysed a subset of the vaccines included in Phase I study plus an additional vaccine. Four laboratories performed the lethal challenge assay and one laboratory carried out the intradermal challenge assay. All laboratories also performed the Vero cell assay and both ELISA for diphtheria antitoxin and ELISA for tetanus antitoxin. One laboratory also performed the tetanus ToBI assay. The correlation coefficient (r) between Vero cell assay and ELISA for diphtheria antitoxin ranged from 0.76 to 0.91 in the different laboratories. The correlation between diphtheria serological assays and challenge assays were confirmed satisfactory as ca. 90 per cent of serum-estimates lead to correct prediction of mortality. All laboratories had identical rankings of the vaccines in all serological assays and in the valid challenge assays. The ranking order was identical to assumed/provided potency for the highest and the lowest vaccine. Two of the vaccines had an inversion in some assays and laboratories. As these two vaccines have almost identical potencies in all assays, these inversions are not significant. As the vaccine doses were optimised for the diphtheria component, serum anti-tetanus toxoid/toxin activities varied widely between the vaccines, making it questionable to apply a parallel line model to calculate exact potencies. However, the dose levels used showed a clear regression and good linearity in general. DTaP vaccines containing the IPV component did not always meet the present Ph. Eur. requirements in the serological assays. It should be further investigated in the Phase III study if this is a general feature of such combined vaccines. Preliminary investigations on samples from two laboratories indicate that the neutralising activity of type 1, 2 and 3 polioviruses can also be detected, in a dose-dependent way. Further studies are in progress with serum samples from other laboratories. In the light of results obtained in the first two phases, it is recommended to proceed with Phase III study to investigate reliability of the in vitro assays. In Phase III it will also be further investigated whether the serological assays for D and T components are suitable for the control of the multi-component vaccines currently marketed in Europe. PMID:14960262
Winsnes, R; Sesardic, D; Daas, A; Behr-Gross, M-E
Intranasal (i.n.) immunization with ricin toxoid (RT) vaccine encapsulated in poly(lactide-co-glycolide) microspheres (RT-PLG-Ms) and poly(L-lactide) microspheres (RT-PLA-Ms) stimulated systemic and mucosal immune responses and protected mice from aerosolized ricin intoxication. High titers of anti-ricin IgG2a were stimulated in the serum of mice with one or two doses of RT-Ms 6 weeks postimmunization. However, in the lungs, no IgG2a or total
Changhong Yan; Wayne L. Rill; Robert Malli; John Hewetson; Hina Naseem; Ralph Tammariello; Meir Kende
Preventing Tetanus, Diphtheria, and Pertussis Among Adults: Use of Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis Vaccine: Recommendation of ACIP, Supported by the Healthcare Infection Control Practices Advisory Committee (HICPAC), for Use of Tdap Among Health-Care Personnel. Morbidity and Mortality Weekly Report, Vol. 55, No. RR-17, December 15, 2006.
On June 10, 2005, a tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Tdap) formulated for use in adults and adolescents was licensed in the United States for persons aged 11-64 years (ADACEL, manufactured by sanofi pasteur, Toron...
I. Ortega-Sanchez K. Kretsinger K. R. Broder M. M. Cortese M. P. Joyce
Meningococcal group X (MenX) is responsible for recent outbreaks of meningitis reported in sub-Saharan region of Africa. Although protective vaccines are available for meningitis, they are not effective against MenX. An efficacious, monovalent conjugate vaccine was designed against MenX and a fed-batch fermentation process was developed. The MenX polysaccharide (PS) was purified and yield estimated to be 15-fold higher than the reported elsewhere. Structure of MenX polysaccharide was confirmed by (1)H, (13)C NMR spectroscopy analysis. Molecular weight of PS was found to be 310 kDa using HPLC-SEC coupled to refractive index (RI) detector. The MenX-Tetanus toxoid (TT) monovalent conjugate proved to be highly immunogenic in mice, and the bactericidal titers of MenX-TT conjugate were 10-fold higher than native PS. Increasing the dose of MenX-TT conjugate from 0.5 ?g to 1.0 ?g induced an 8-fold higher antibody titer as well as serum bactericidal titer. The current work suggests that the MenX-TT conjugate is a candidate vaccine against meningitis caused by Meningococcal group X strains. PMID:24411634
Chilukuri, Srinivas Reddy; Reddy, Peddi; Avalaskar, Nikhil; Mallya, Asha; Pisal, Sambhaji; Dhere, Rajeev M
The aim of this study was to investigate whether Spirulina (Arthrospira) supplementation could enhance the immune response to tetanus toxoid (TT) vaccine in a mouse model. Vaccination of TT was performed on day 7 and 21 in mice fed daily with Spirulina (50 and 150 mg/kg body weight). Both Spirulina supplementation and TT vaccination did not significantly affect body weight gain of the mice. Supplementation of Spirulina significantly enhanced IgG level (p = .01) after the first but not after the second TT vaccination. The anti-TT IgG levels of the groups that received low dose and high dose of Spirulina were not significantly different. Spirulina supplementation did not show significant effects on in vitro splenocyte proliferation and cytokine (IFN-? and IL-4) production induced by Con A and TT. This study showed that Spirulina supplementation could enhance primary immune response in terms of antibody production, but not secondary immune response following TT vaccination in a mouse model. PMID:23927690
Chu, Wan-Loy; Quynh, Le Van; Radhakrishnan, Ammu Kutty
Objective-To determine the efficacy of a multivalent modified-live virus (MLV) vaccine containing a Mannheimia haemolytica toxoid to reduce pneumonia and mortality rate when administered to calves challenge exposed with virulent Bibersteinia trehalosi. Animals-74 Holstein calves. Procedures-Calves were assigned to 2 treatment groups. Calves in the control group (n = 36) were vaccinated by SC administration of 2 mL of a commercial 5-way MLV vaccine, and calves in the other group (38) were vaccinated by SC administration of a 2-mL dose of a 5-way MLV vaccine containing M haemolytica toxoid (day 0). On day 21, calves were transtracheally administered B trehalosi. Serum was obtained for analysis of antibody titers against M haemolytica leukotoxin. Nasopharyngeal swab specimens were collected from calves 1 day before vaccination (day -1) and challenge exposure (day 20) and cultured to detect bacterial respiratory pathogens. Clinical scores, rectal temperature, and death attributable to the challenge-exposure organism were recorded for 6 days after challenge exposure. Remaining calves were euthanized at the end of the study. Necropsy was performed on all calves, and lung lesion scores were recorded. Results-Calves vaccinated with the MLV vaccine containing M haemolytica toxoid had significantly lower lung lesion scores, mortality rate, and clinical scores for respiratory disease, compared with results for control calves. Conclusions and Clinical Relevance-Administration of a multivalent MLV vaccine containing M haemolytica toxoid protected calves against challenge exposure with virulent B trehalosi by reducing the mortality rate, lung lesion scores, and clinical scores for respiratory disease. PMID:25061709
Bowersock, Terry L; Sobecki, Brian E; Terrill, Sarah J; Martinon, Nathalie C; Meinert, Todd R; Leyh, Randy D
To test for immunologic memory after a single dose of meningococcal C conjugate (MCC) vaccine in toddlers, 226 children 12-18 months old were randomized to receive 1 of 3 MCC vaccines, with a C polysaccharide booster 6 months later. The protein conjugate was diphtheria mutant toxoid in 2 vaccines (MCC-CRM(197)) and was tetanus toxoid in the third (MCC-TT). One month after the MCC vaccines, 91%-100% of children had serum bactericidal antibody (SBA) titers > or =8, and 89%-100% had a > or =4-fold increase. Geometric mean titer (GMT) increased from <4 to 215 (95% confidence interval [CI], 166-279). MCC-TT induced higher SBA GMTs (P<.001) and higher proportions with SBA > or =8 (P=.02) than did the MCC-CRM(197) vaccines. By 6 months, GMTs had decreased to 55.1 (95% CI, 40-76), but IgG antibody avidity increased (P<.001). Induction of immunologic memory was confirmed by a GMT of 1977 (range, 1535-2547) after the polysaccharide booster and a further increase in avidity. This evidence justified the use of a single dose in a catch-up immunization program for children 1-18 years old. PMID:11078484
Richmond, P; Borrow, R; Goldblatt, D; Findlow, J; Martin, S; Morris, R; Cartwright, K; Miller, E
This study investigated the use of two doses of three different meningococcal group C conjugate (MCC) vaccines when given for primary immunization with a seven-valent pneumococcal conjugate vaccine (PCV7) and Pediacel, a combination product containing five acellular pertussis components, diphtheria and tetanus toxoids, Haemophilus influenzae type b (Hib) conjugate, and inactivated-poliovirus vaccine. The immune response after a single dose of MCC is also presented. Infants were randomized to receive two doses of one of the MCC vaccines and PCV7 at 2 and 3 months or at 2 and 4 months of age. Meningococcal group C serum bactericidal antibody (SBA) geometric mean titers, Hib-polyribosylribitol phosphate (PRP) immunoglobulin G (IgG) geometric mean concentrations (GMCs), and diphtheria and tetanus antitoxin GMCs, together with the proportions of infants achieving putative protective levels, were determined. A total of 393 infants were recruited. Following the first dose of NeisVac-C (MCC conjugated to tetanus toxoid), 97% of infants achieved protective levels (SBA titer of ?8), compared with 80% and 53%, respectively, for Menjugate and Meningitec (both of which are conjugated to CRM197). SBA responses to MCC vaccines were not significantly different when administered at 2 and 3 or 2 and 4 months of age. Following two doses of each MCC, 98 to 100% of infants achieved protective levels. Both PRP IgG and tetanus responses were significantly enhanced when Pediacel was coadministered with NeisVac-C. This study demonstrates that NeisVac-C and Menjugate generate good immunogenicity after the first dose at 2 months of age when coadministered with PCV7 and Pediacel and merit further investigation in single-dose priming strategies.
Southern, Jo; Borrow, Ray; Andrews, Nick; Morris, Rhonwen; Waight, Pauline; Hudson, Michael; Balmer, Paul; Findlow, Helen; Findlow, Jamie; Miller, Elizabeth
Tetanus toxoids (i.e. chemically inactivated preparations of tetanus neurotoxin) are used for the production of tetanus vaccines. In order to exclude the risk of residual toxicity or of a "reversion to toxicity", each batch of tetanus toxoid is subject to strict safety testing. Up to now, these prescribed safety tests have to be performed as in vivo toxicity tests in guinea pigs. However, as animal tests are generally slow, costly and ethically disputable, a replacement by an in vitro method would be desirable. A suitable alternative method would have to be able to sensitively detect already low concentrations of active tetanus neurotoxin in matrices containing large amounts of inactivated toxoid molecules. We have developed a method which detects active tetanus neurotoxin molecules based on their specific receptor-binding capacity as well as their proteolytic activity. By taking into account two relevant functional characteristics, this combined "BINding And CLEavage" (BINACLE) assay more reliably discriminates between toxic and detoxified molecules than other in vitro assays which solely rely on one single toxin function (e.g. endopeptidase assays). Data from an in-house validation show that the BINACLE assay is able to detect active tetanus neurotoxin with a detection limit comparable to the in vivo test. The sensitive detection of active toxin which has been spiked into toxoid samples from different manufacturers could also be demonstrated. Specificity and precision of the method have been shown to be satisfactory. The presented data indicate that for toxoid batches from some of the most relevant European vaccine manufacturers, the BINACLE assay may represent a potential alternative to the prescribed animal safety tests. In addition, this novel method may also provide a convenient tool for monitoring batch-to-batch consistency during toxoid production. PMID:24156922
Behrensdorf-Nicol, Heike A; Bonifas, Ursula; Hanschmann, Kay-Martin; Krämer, Beate; Weißer, Karin
Pneumococcal conjugate vaccines are highly effective in preventing invasive disease in infants and young children, with favorable safety and immunogenicity profiles. These pediatric vaccines have also shown efficacy in reducing cases of non-invasive disease (i.e. otitis media, pneumonia). Recently, pneumococcal conjugate vaccines have demonstrated additional protective qualities that may enhance their use worldwide. For example, they can reduce nasopharyngeal acquisition
Katherine L O’Brien; Ron Dagan
Staphylococcal enterotoxin B (SEB), a primary cause of food poisoning, is also a superantigen that can cause toxic shock after traumatic or surgical staphylococcal wound [correction of would] infections or viral influenza-associated staphylococcal superinfections or when aerosolized for use as a potential biologic warfare threat agent. Intranasal or intramuscular (i.m.) immunization with formalinized SEB toxoid formulated with meningococcal outer membrane protein proteosomes has previously been shown to be immunogenic and protective against lethal respiratory or parenteral SEB challenge in murine models of SEB intoxication. Here, it is demonstrated that immunization of nonhuman primates with the proteosome-SEB toxoid vaccine is safe, immunogenic, and protective against lethal aerosol challenge with 15 50% lethal doses of SEB. Monkeys (10 per group) were primed i.m. and given booster injections by either the i.m. or intratracheal route without adverse side effects. Anamnestic anti-SEB serum immunoglobulin G (IgG) responses were elicited in all monkeys, but strong IgA responses in sera and bronchial secretions were elicited both pre- and post-SEB challenge only in monkeys given booster injections intratracheally. The proteosome-SEB toxoid vaccine was efficacious by both routes in protecting 100% of monkeys against severe symptomatology and death from aerosolized-SEB intoxication. These data confirm the safety, immunogenicity, and efficacy in monkeys of parenteral and respiratory vaccination with the proteosome-SEB toxoid, thereby supporting clinical trials of this vaccine in humans. The safety and enhancement of both bronchial and systemic IgA and IgG responses by the proteosome vaccine delivered by a respiratory route are also encouraging for the development of mucosally delivered proteosome vaccines to protect against SEB and other toxic or infectious respiratory pathogens.
Lowell, G H; Colleton, C; Frost, D; Kaminski, R W; Hughes, M; Hatch, J; Hooper, C; Estep, J; Pitt, L; Topper, M; Hunt, R E; Baker, W; Baze, W B
Staphylococcal enterotoxin B (SEB), a primary cause of food poisoning, is also a superantigen that can cause toxic shock after traumatic or surgical staphylococcal wound [correction of would] infections or viral influenza-associated staphylococcal superinfections or when aerosolized for use as a potential biologic warfare threat agent. Intranasal or intramuscular (i.m.) immunization with formalinized SEB toxoid formulated with meningococcal outer membrane protein proteosomes has previously been shown to be immunogenic and protective against lethal respiratory or parenteral SEB challenge in murine models of SEB intoxication. Here, it is demonstrated that immunization of nonhuman primates with the proteosome-SEB toxoid vaccine is safe, immunogenic, and protective against lethal aerosol challenge with 15 50% lethal doses of SEB. Monkeys (10 per group) were primed i.m. and given booster injections by either the i.m. or intratracheal route without adverse side effects. Anamnestic anti-SEB serum immunoglobulin G (IgG) responses were elicited in all monkeys, but strong IgA responses in sera and bronchial secretions were elicited both pre- and post-SEB challenge only in monkeys given booster injections intratracheally. The proteosome-SEB toxoid vaccine was efficacious by both routes in protecting 100% of monkeys against severe symptomatology and death from aerosolized-SEB intoxication. These data confirm the safety, immunogenicity, and efficacy in monkeys of parenteral and respiratory vaccination with the proteosome-SEB toxoid, thereby supporting clinical trials of this vaccine in humans. The safety and enhancement of both bronchial and systemic IgA and IgG responses by the proteosome vaccine delivered by a respiratory route are also encouraging for the development of mucosally delivered proteosome vaccines to protect against SEB and other toxic or infectious respiratory pathogens. PMID:8890226
Lowell, G H; Colleton, C; Frost, D; Kaminski, R W; Hughes, M; Hatch, J; Hooper, C; Estep, J; Pitt, L; Topper, M; Hunt, R E; Baker, W; Baze, W B
Moraxella catarrhalis is an important bacterial cause of otitis media in children and respiratory tract infections in the elderly. Lipooligosaccharide (LOS), a major surface antigen of this bacterium, is a potential vaccine component against the organism. There are three major LOS serotypes (serotypes A, B, and C) in clinical isolates of M. catarrhalis. Our previous studies demonstrated that serotype A and B LOS-based conjugates were immunogenic in animals and elicited bactericidal antibodies. In this study, LOS from serotype C strain 26404 was isolated, detoxified, and conjugated to tetanus toxoid (TT) or the cross-reactive mutant (CRM) of diphtheria toxin to form detoxified LOS (dLOS)-TT, dLOS-CRM-1, and dLOS-CRM-2 vaccine candidates. The molar ratios (dLOS/protein) of the resulting conjugates were 47:1, 19:1, and 32:1, respectively, while the weight ratios were 0.94, 0.84 and 1.44, respectively. All conjugates were highly immunogenic in both mouse and rabbit models. Three subcutaneous injections of each conjugate formulated with the Ribi adjuvant elicited >700-fold increases in serum anti-LOS immunoglobulin G levels in mice (5 microg of dLOS) and >2,000-fold increases in rabbits (50 microg of dLOS). The resulting mouse and rabbit antisera showed complement-mediated bactericidal activity against the homologous strain. In addition, a representative rabbit antiserum showed bactericidal activity against 14 of 18 testable strains, and this bactericidal activity could be 100% inhibited by the serotype C or A LOS but only 30% inhibited by the serotype B LOS. These results indicate that the serotype C LOS-based conjugates can be used as vaccine components for further investigation in humans. PMID:17371852
Yu, Shengqing; Gu, Xin-Xing
We evaluated two formulations of a new combined Haemophilus influenzae type b (Hib)-meningococcal serogroup C (MenC)-tetanus toxoid (TT) conjugated vaccine and two formulations of a new MenC-TT vaccine (trials 711202/001 and 711202/008; clinical trial register numbers NCT00135486 and NCT00135564 [www.ClinicalTrials.gov]). A total of 520 healthy infants were randomized to receive primary vaccination (at 2, 3, and 4 months) with either MenC-TT plus diphtheria-tetanus-acellular pertussis (DTPa)-hepatitis B virus (HBV)-inactivated poliovirus (IPV)/Hib, Hib-MenC-TT plus DTPa-HBV-IPV, or MenC-CRM197 plus DTPa-HBV-IPV/Hib (control). At 12 to 15 months, subjects received a polysaccharide challenge with meningococcal polysaccharide C plus a DTPa-HBV-IPV/Hib booster. Immune responses were assessed 1 month after dose 2, 1 month after dose 3, and prior to and 1 month after the booster. After primary vaccination, there was no difference between groups in seroprotection rates as measured by titers of serum bactericidal antibody (SBA) to MenC (?1:8) or concentrations of anti-polyribosyl ribitol phosphate (PRP) antibody (?0.15 ?g/ml). Prior to the booster, there was no difference between groups in SBA seroprotection rates, whereas anti-PRP seroprotection rates were significantly higher after priming with Hib-MenC-TT. Booster doses induced large increases in SBA and anti-PRP antibodies in primed groups, indicating successful priming with induction of immune memory. Reactogenicity and safety were similar in all groups during the primary and booster phases. A novel combined Hib-MenC-TT conjugate vaccine induced MenC and Hib responses comparable to those induced by licensed monovalent vaccines. A Hib-MenC-TT conjugate vaccine provides vaccination against two major pathogens in a single injection and is a suitable candidate for use in primary or booster vaccination schedules.
Schmitt, Heinz-J.; Maechler, Gudrun; Habermehl, Pirmin; Knuf, Markus; Saenger, Roland; Begg, Norman; Boutriau, Dominique
Group B Streptococcus (GBS) is a leading cause of human neonatal bacterial disease, resulting in pneumonia, sepsis, meningitis and sometimes, death. Supportive preclinical studies of GBS capsular polysaccharide (CPS)-protein conjugate vaccines have led to several phase 1 and phase 2 trials in healthy, non-pregnant adults, which demonstrated that the vaccines, produced at the Channing Laboratory, were safe and immunogenic. However, evaluation of the safety and immunogenicity of a GBS conjugate vaccine administered to pregnant women demanded that it be manufactured under current good manufacturing practices (cGMP) and that it undergo developmental toxicity evaluation. In this report, we describe a GBS type III CPS-tetanus toxoid (III-TT) vaccine lot 3-1-96 manufactured and vialed under cGMP and our evaluation of the effect of this vaccine and of GBS type III CPS-specific antibody on conception and early- and late-stage fetal development in rabbits. III-TT lot 3-1-96 was compositionally similar to prototype III-TT lot 91-1, produced under non-GMP, and was potent in a mouse maternal vaccination-neonatal pup challenge model of GBS disease. Four groups of 30 female rabbits each were randomized to receive III-TT lot 3-1-96 vaccine, saline-alum, or combinations of these treatments before and after insemination. The dose of conjugated CPS on a weight basis was 1 ?g/kg, mimicking the anticipated actual human dose. Based on the weight of the rabbits, this was 20- to 100-fold greater than the expected human dose. Does were pre-assigned to deliver litters naturally or have their kits delivered by Caesarean-section at gestation day 29, to assess late fetal development. Sera from does and kits were collected, and the presence of type III CPS-specific IgG was confirmed by quantitative ELISA. Based on all assessments, GBS type III-TT lot 3-1-96, nor antibody to it did not affect embryo-fetal viability, sex ratio, growth or cause malformations (i.e., it was non-teratogenic). In addition, that III-TT lot 3-1-96 was found to be safe and immunogenic in two clinical studies involving healthy non-pregnant adults supports a clinical evaluation of this vaccine in pregnant women.
Paoletti, Lawrence C.; Guttormsen, Hilde-Kari; Christian, Mildred S.; Hoberman, Alan M.; McInnes, Pamela
Neisseria meningitidis group C is an encapsulated bacterium that causes several diseases and is associated with high mortality rates, thereby constituting a serious public health problem. Bio-Manguinhos/Fiocruz is developing a conjugate vaccine by covalent attachment of capsular polysaccharide to hydrazide-activated tetanus toxoid through reductive amination. It is necessary to quantify free components as a quality control process to prevent exacerbated adverse reactions and/or attenuation of vaccine immunogenicity. Thus, this study aimed to develop and validate a quality control method appropriate for the separation and quantification of free polysaccharide present in this conjugate N. meningitidis group C vaccine using CE. CZE was used to remove unbound polysaccharide, and the electrophoretic conditions were varied to optimize resolution. We were able to develop and validate the proposed method, which was linear and showed a matrix effect. Repeatability and partial reproducibility of the method were also evaluated. The robustness results showed that control of temperature is required for reliable results. The validated method will be used to evaluate the conjugate batches submitted for Phase III clinical studies and for routine quality control of the conjugate vaccine. PMID:24037919
Medeiros de Souza, Iaralice; Neto da Silva, Milton; Figueira, Elza Scott; Leal, Maria de Lourdes; Jessouroun, Ellen; Pereira Abrantes, Shirley de Mello; Brasileiro da Silveira, Ivna Alana Freitas
Moraxella catarrhalis is an important cause of otitis media in children and respiratory tract infections in the elderly. Lipooligosaccharide (LOS) is a major surface antigen of the bacterium that elicits bactericidal antibodies. Serological studies show that three major LOS types (A, B, and C) have been identified among clinical isolates. Our previous studies demonstrated that the type A LOS-based conjugates were immunogenic in animals. In this study, LOS from type B strain 26397 was detoxified and conjugated to tetanus toxoid (TT) or a cross-reactive mutant (CRM) of diphtheria toxin to form detoxified LOS (dLOS)-TT and dLOS-CRM, respectively, as vaccine candidates. The molar ratios of dLOS to TT and CRM in the conjugates were 43:1 and 19:1, respectively, while both weight ratios were around 0.9. The antigenicity of the conjugates was similar to that of the LOS, as determined by enzyme-linked immunosorbent assay using a rabbit antiserum to strain 26397. Subcutaneous immunization with each conjugate elicited a 180- to 230-fold rise of serum anti-LOS immunoglobulin G in mice and >2,000-fold rise in rabbits. In addition, both mouse and rabbit antisera showed elevated complement-mediated bactericidal activity against the homologous strain, and a representative rabbit antiserum showed bactericidal activity against nine of twelve clinical isolates studied. The bactericidal activity of the rabbit antiserum can be fully inhibited by the type B LOS but not the A or C LOS. These results indicate that the type B LOS-based conjugates can be used as vaccine components for further investigation. PMID:15845482
Yu, Shengqing; Gu, Xin-Xing
Procedures were developed for preparing purified aluminum-phosphate-absorbed, univalent, bivalent, and pentavalent botulinum toxoids to immunize man. All preparations were well tolerated and elicited satisfactory antitoxin responses in man, whether admini...
M. A. Cardella
Recently, conjugate vaccines containing Haemophilus influenzae type b capsular polysaccharide (HibCP) coupled to protein carriers were introduced for use in infants and certain adult risk groups. Similar conjugate vaccines against other capsulated bacteria are currently under development for both children and adults. Despite its potential importance, the possible influence of preexisting immunity to the components of such conjugates on the vaccination response in humans has been addressed by few studies. To study this issue, we randomized 82 healthy adult volunteers into six groups and vaccinated them twice, with a 4-week interval between immunizations. Four groups received tetanus toxoid (TT) or diphtheria toxoid (DT) and then HibCP coupled to TT (HibCP-TT) or DT (HibCP-DT). Two groups received HibCP-TT followed by HibCP-DT or vice versa. The total antibody levels to HibCP, TT, and DT and the anti-HibCP immunoglobulin G1 (IgG1) and IgG2 levels were measured before and 4 weeks after the immunizations. For some of the vaccinees, the number of circulating antibody-secreting cells was evaluated 7 days after immunization. Surprisingly, preimmunization with the relevant carrier protein reduced the subsequent increase in the total HibCP antibody levels (P < 0.05), affecting the IgG1 and the IgG2 subclasses equally. Also, the responses to the carrier portions of the conjugates were suppressed, as demonstrated by the lack of significant increases in the antibody levels (P > or = 0.29) and, for HibCP-TT, by reduced numbers of anticarrier antibody-secreting cells (P = 0.009). Similar non-epitope-specific suppression was seen in the groups receiving both conjugates. Thus, preimmunization with one conjugate reduced the subsequent response to the carrier portion of the other conjugate (HibCP-DT and then HibCP-TT, P = 0.00002; HibCP-TT and then HibCP-DT, P = 0.06) as well as to HibCP itself. Possible mechanisms behind this non-epitope-specific suppression and its relevance for vaccine development are discussed.
Barington, T; Skettrup, M; Juul, L; Heilmann, C
Serogroup C meningococcal (MenC) disease accounts for one-third of all meningococcal cases and causes meningococcal outbreaks in the U.S. Quadrivalent meningococcal vaccine conjugated to diphtheria toxoid (MenACYWD) was recommended in 2005 for adolescents and high risk groups such as military recruits. We evaluated anti-MenC antibody persistence in U.S. military personnel vaccinated with either MenACYWD or meningococcal polysaccharide vaccine (MPSV4). Twelve hundred subjects vaccinated with MenACYWD from 2006 to 2008 or MPSV4 from 2002 to 2004 were randomly selected from the Defense Medical Surveillance System. Baseline serologic responses to MenC were assessed in all subjects; 100 subjects per vaccine group were tested during one of the following six post-vaccination time-points: 5-7, 11-13, 17-19, 23-25, 29-31, or 35-37 months. Anti-MenC geometric mean titers (GMT) were measured by rabbit complement serum bactericidal assay (rSBA) and geometric mean concentrations (GMC) by enzyme-linked immunosorbent assay (ELISA). Continuous variables were compared using the Wilcoxon rank sum test and the proportion of subjects with an rSBA titer ?8 by chi-square. Pre-vaccination rSBA GMT was <8 for the MenACWYD group. rSBA GMT increased to 703 at 5-7 months post-vaccination and decreased by 94% to 43 at 3 years post-vaccination. GMT was significantly lower in the MenACWYD group at 5-7 months post-vaccination compared to the MPSV4 group. The percentage of MenACWYD recipients achieving an rSBA titer of ?8 decreased from 87% at 5-7 months to 54% at 3 years. There were no significant differences between vaccine groups in the proportion of subjects with a titer of ?8 at any time-point. GMC for the MenACWYD group was 0.14?g/mL at baseline, 1.07?g/mL at 5-7 months, and 0.66?g/mL at 3 years, and significantly lower than the MPSV4 group at all time-points. Anti-MenC responses wane following vaccination with MenACYWD; a booster dose is needed to maintain protective levels of circulating antibody. PMID:24837781
Patel, Manisha; Romero-Steiner, Sandra; Broderick, Michael P; Thomas, Cynthia G; Plikaytis, Brian D; Schmidt, Daniel S; Johnson, Scott E; Milton, Andrea S; Carlone, George M; Clark, Thomas A; Messonnier, Nancy E; Cohn, Amanda C; Faix, Dennis J
Synthesis, characterization, and immunological properties in mice of conjugates composed of detoxified lipopolysaccharide of Salmonella paratyphi A bound to tetanus toxoid with emphasis on the role of O acetyls.
Salmonella paratyphi A, the second most common cause of enteric fever in Southeast Asia, is a habitant of and a pathogen for humans only. Lipopolysaccharides (LPS) are both essential virulence factors and protective antigens for systemic infections caused by groups A, B, C, and D nontyphoidal salmonellae. The O-specific polysaccharide of S. paratyphi A is composed of a trisaccharide, -->2-alpha-D)-Manp-(1-->4)-alpha-L-Rhap-(1-->3)-alpha-D-Galp -(1-->, with a branch of D-paratose from the C-3 of alpha-D-mannose, and the C-3 of beta-L-rhamnose is partially O acetylated (C. G. Hellerqvist, B. Lindberg, K. Samuelsson, and A. A. Lindberg, Acta Chem. Scand. 25:955-961, 1971). On the basis of data from our investigational vaccines for enteric bacterial pathogens, including group B salmonellae (D. C. Watson, J. B. Robbins, and S. C. Szu, Infect. Immun. 60:4679-4686, 1992), conjugates composed of the detoxified LPS of S. paratyphi A bound to tetanus toxoid (TT) were prepared by several schemes. LPS was detoxified with acetic acid or with hydrazine; the latter removed O acetyls from the O-specific polysaccharide. The detoxified polysaccharides were activated with cyanogen bromide (CNBr) or with 1-cyano-4-dimethylaminopyridinium tetratfluoroborate (CDAP) and bound to TT with or without a spacer. Solutions of 2.5 microgram of saccharide, alone or as a conjugate, were injected subcutaneously into young mice, and LPS and TT antibodies were measured by enzyme-linked immunosorbent assaying. A conjugate synthesized with higher-molecular-weight O-SP elicited the highest anti-LPS levels. Only conjugates with O acetyls elicited serum immunoglobulin G anti-LPS with bactericidal activity. There were no statistically significant differences between LPS antibody levels elicited by conjugates synthesized with or without a spacer. The conjugate with O-specific polysaccharide activated by CDAP and bound to TT without a spacer elicited the highest level of TT antibodies. Clinical evaluation (if S. paratyphi A conjugates is planned.
Konadu, E; Shiloach, J; Bryla, D A; Robbins, J B; Szu, S C
BACKGROUNDGroup C conjugate meningococcal vaccines (Men C) were introduced into the UK primary immunisation schedule in November 1999. There has been extensive professional and public interest in their efficacy and safety.AIMTo determine the occurrence of at least one uncommon adverse event in infants related to the administration of the Chiron Men C vaccine.METHODSA total of 2796 infants aged approximately 2
R Lakshman; I Jones; D Walker; K McMurtrie; L Shaw; G Race; S Choo; L Danzig; P Oster; A Finn
Background Although a combined Haemophilus influenzae type b (Hib)/meningococcal capsular group C (MenC) conjugate vaccine with a tetanus toxoid carrier protein (Hib/MenC-TT) is not licensed for use in those above 2 years of age due to lack of data on safety and efficacy, certain patient groups at high risk of MenC and/or Hib disease are recommended to receive it. Laboratory workers working with Hib and/or MenC cultures may be at a potentially increased risk of acquiring infectious diseases and vaccination is therefore an important safety consideration. We undertook a clinical trial to investigate the safety and immunogenicity of Hib/MenC-TT vaccine in this cohort. Methods A total of 33 subjects were recruited to the trial, all of whom were vaccinated. Serology was completed on samples taken at baseline and four weeks following vaccination to determine MenC specific IgG, MenC serum bactericidal antibody (SBA), anti-Hib polyribosylribitol phosphate (PRP) IgG and anti-tetanus toxoid IgG responses. Results At baseline, high proportions of subjects had protective antibody concentrations against MenC, Hib and tetanus due to previous vaccination and/or natural exposure. Vaccination induced?>?3, 10 and 220 fold increases in geometric mean concentrations for MenC SBA, anti-tetanus toxoid IgG and anti-Hib PRP IgG, respectively. Following vaccination, 97% of subjects had putative protective SBA titres???8, 100% had short term protective anti-Hib PRP IgG concentrations???0.15 ?g/mL and 97% had protective anti-tetanus toxoid concentrations???0.1 IU/mL. No safety concerns were reported with minor local reactions being reported by 21% of subjects. Conclusions Immunological responses determined in this trial are likely a combination of primary and secondary responses due to previous vaccination and natural exposure. Subjects were a representative cross-section of laboratory workers, enabling us to conclude that a single dose of Hib/MenC-TT was safe and immunogenic in healthy adults providing the evidence that this vaccine may be used for providing protection in an occupational setting.
...Cyanamid Company, No. 17. Diphtheria and Tetanus Toxoids and Pertussis Vaccine Adsorbed.\\2\\ Diphtheria and Tetanus Toxoids Adsorbed...Toxoid Adsorbed.\\5\\ Diphtheria and Tetanus Toxoids and Pertussis Vaccine...
The first conjugate vaccine was approved for use in the US in 1988 to protect infants and young children against the capsular bacteria Haemophilus influenzae type b (Hib). Since its introduction in the US, this vaccine has been approved in most developed countries, including Denmark and Israel where the vaccine was added to their national vaccine programs in 1993 and 1994, respectively. There have been marked increases in the reported prevalence of autism spectrum disorders (ASDs) among children in the US beginning with birth cohorts in the late 1980s and in Denmark and Israel starting approximately 4-5 years later. Although these increases may partly reflect ascertainment biases, an exogenous trigger could explain a significant portion of the reported increases in ASDs. It is hypothesized here that the introduction of the Hib conjugate vaccine in the US in 1988 and its subsequent introduction in Denmark and Israel could explain a substantial portion of the initial increases in ASDs in those countries. The continuation of the trend toward increased rates of ASDs could be further explained by increased usage of the vaccine, a change in 1990 in the recommended age of vaccination in the US from 15 to 2 months, increased immunogenicity of the vaccine through changes in its carrier protein, and the subsequent introduction of the conjugate vaccine for Streptococcus pneumoniae. Although conjugate vaccines have been highly effective in protecting infants and young children from the significant morbidity and mortality caused by Hib and S. pneumoniae, the potential effects of conjugate vaccines on neural development merit close examination. Conjugate vaccines fundamentally change the manner in which the immune systems of infants and young children function by deviating their immune responses to the targeted carbohydrate antigens from a state of hypo-responsiveness to a robust B2 B cell mediated response. This period of hypo-responsiveness to carbohydrate antigens coincides with the intense myelination process in infants and young children, and conjugate vaccines may have disrupted evolutionary forces that favored early brain development over the need to protect infants and young children from capsular bacteria. PMID:21993250
Richmand, Brian J
There is no licensed vaccine available against Moraxella catarrhalis, an exclusive human pathogen responsible for otitis media in children and respiratory infections in adults. We previously developed conjugate vaccine candidates based on lipooligosaccharides (LOSs) of M. catarrhalis serotypes A, B, and C, each of which was shown to cover a portion of the clinical strains. To generate conserved LOS antigens and eliminate a potential autoimmune response to a similar epitope between M. catarrhalis LOS moiety Gal?1-4Gal?1-4Glc and human Pk antigen, two LOS mutants from strain O35E were constructed. Mutant O35Elgt5 or O35EgalE revealed a deletion of one or two terminal galactose residues of wild type O35E LOS. Each LOS molecule was purified, characterized, detoxified, and coupled to tetanus toxoid (TT) to form conjugates, namely dLOS-TT. Three subcutaneous immunizations using dLOS-TT from O35Elgt5 or O35EgalE elicited significant increases (a 729- or 1263-fold above the preimmune serum levels) of serum immunoglobulin (Ig)G against O35E LOS in rabbits with an adjuvant or without an adjuvant (an 140- or 140-fold above the preimmune serum levels). Rabbit antisera demonstrated elevated complement-mediated bactericidal activities against the wild type strain O35E. The rabbit sera elicited by O35Elgt5 dLOS-TT were further examined and showed cross bactericidal activity against all additional 19 M. catarrhalis strains and clinical isolates studied. Moreover, the rabbit sera displayed cross-reactivity not only among three serotype strains but also clinical isolates in a whole-cell enzyme-linked immunosorbent assay (ELISA), which was further confirmed under transmission electron microscopy. In conclusion, O35Elgt5 dLOS-TT may act as a vaccine against most M. catarrhalis strains and therefore can be used for further in vivo efficacy studies.
Ren, Dabin; Yu, Shengqing; Gao, Song; Peng, Daxin; Petralia, Ronald S.; Muszynski, Artur; Carlson, Russell W.; Robbins, John B.; Lim, David J.; Gu, Xin-Xing
Pneumococcal conjugate vaccination has proved highly effective in eliminating vaccine-type pneumococcal carriage and disease. However, the potential adverse effects of serotype replacement remain a major concern when implementing routine childhood pneumococcal conjugate vaccination programmes. Applying a concise predictive model, we present a ready-to-use quantitative tool to investigate the implications of serotype replacement on the net effectiveness of vaccination against invasive pneumococcal disease (IPD) and to guide in the selection of optimal vaccine serotype compositions. We utilise pre-vaccination data on pneumococcal carriage and IPD and assume partial or complete elimination of vaccine-type carriage, its replacement by non-vaccine-type carriage, and stable case-to-carrier ratios (probability of IPD per carriage episode). The model predicts that the post-vaccination IPD incidences in Finland for currently available vaccine serotype compositions can eventually decrease among the target age group of children <5 years of age by 75%. However, due to replacement through herd effects, the decrease among the older population is predicted to be much less (20–40%). We introduce a sequential algorithm for the search of optimal serotype compositions and assess the robustness of inferences to uncertainties in data and assumptions about carriage and IPD. The optimal serotype composition depends on the age group of interest and some serotypes may be highly beneficial vaccine types in one age category (e.g. 6B in children), while being disadvantageous in another. The net effectiveness will be improved only if the added serotype has a higher case-to-carrier ratio than the average case-to-carrier ratio of the current non-vaccine types and the degree of improvement in effectiveness depends on the carriage incidence of the serotype. The serotype compositions of currently available pneumococcal vaccines are not optimal and the effectiveness of vaccination in the population at large could be improved by including new serotypes in the vaccine (e.g. 22 and 9N).
Nurhonen, Markku; Auranen, Kari
We evaluated the safety and immunogenicity of two octavalent pneumococcal polysaccharide vaccines (serotypes 3, 4, 6B, 9V, 14, 18C, 19F, and 23F) conjugated to either diphtheria toxoid (PncD) or tetanus protein (PncT) among White Mountain Apache and Gila River Indian Community infants. This was a prospective, non-randomized, open label, comparative pilot study of PncD and PncT. Since this was a pilot study, a small sample size of 60 infants was enrolled. Enrolled healthy infants received either PncD or PncT at 2, 4, and 6 months of age. Antibody concentrations were measured by enzyme-immunoassay (EIA) prior to each dose and 1 month after the last dose. Local reaction rates were similar between PncD and PncT groups. The geometric mean concentrations (GMCs) were significantly higher for PncD than PncT for serotype 3 whereas GMCs were significantly higher for PncT for serotype 4. For this pilot study, both vaccines appeared to be safe and immunogenic in this group of American Indian infants. PMID:15003655
Eick, Angelia; Croll, Janné; Weatherholtz, Robert; Croll, Larry; Santosham, Mathuram
Covalent binding to immunogenic proteins increases the immunogenicity of the capsular polysaccharides of Haemophilus influenzae type b (Hib) and pneumococcus type 6A (Pn6A). Conjugates composed of Hib, Pn6A, or the cross-reacting Escherichia coli K100 covalently bound to tetanus toxoid (TT) were injected into young adult volunteers. Local reactions were common and were probably due to Arthus reactivity mediated by the preexisting antibodies reacting with the TT component of the conjugates. Fever occurred in about 10% of the volunteers after the first injection; no volunteers had fever after the second injection. Similar levels of Hib or Pn6A antibodies were elicited by either 50- or 100-micrograms doses or by concurrent injection of two different conjugates (Hib-TT and Pn6A-TT or Hib-TT and K100-TT). The Hib-TT elicited about a 180-fold increase in Hib antibodies, and the Pn6A-TT conjugate elicited about an 8-fold increase in Pn6A antibodies after one injection. Booster reactions were not elicited in adults; similar levels of antibodies in the five experimental groups suggested that the responses elicited by the conjugates were maximal. A one-way cross-reaction was noted as Pn6A conjugates elicited rises of Hib antibodies in 13 of 20 volunteers; only 4 of 59 volunteers immunized with Hib-TT had increases in Pn6A antibodies. The preimmunization Hib antibodies were composed of immunoglobulin M (IgM), IgA, and IgG. The postimmunization sera showed an increase in all three isotypes; the elevation of the IgG was the highest of the three isotypes. Conjugate-induced antibodies to both the polysaccharide and TT exerted biological activities that have been correlated with immunity. Adsorption of the Hib-TT onto aluminium hydroxide resulted in higher levels and an earlier Hib antibody response in infant rhesus. These results encourage the evaluation of Hib and Pn6A conjugates in human children and infants.
Schneerson, R; Robbins, J B; Parke, J C; Bell, C; Schlesselman, J J; Sutton, A; Wang, Z; Schiffman, G; Karpas, A; Shiloach, J
BACKGROUND: Gambia is the second GAVI support-eligible country to introduce the 7-valent pneumococcal conjugate vaccine (PCV7), but a country-specific cost-effectiveness analysis of the vaccine is not available. Our objective was to assess the potential impact of PCVs of different valences in The Gambia. METHODS: We synthesized the best available epidemiological and cost data using a state-transition model to simulate the
Sun-Young Kim; Gene Lee; Sue J Goldie
Currently available live oral rotavirus vaccines, Rotarix(®) and RotaTeq(®), are highly efficacious in developed countries. However, the immunogenicity and efficacy of such vaccines in some developing countries are low. We reported previously that bacterially-expressed rotavirus ?VP8* subunit vaccine candidates with P, P or P specificity elicited high-titer virus neutralizing antibodies in animals immunized intramuscularly. Of note was the finding that antibodies induced with the P?VP8* vaccine neutralized both homotypic P and heterotypic P rotavirus strains to high titer. To further improve its vaccine potential, a tetanus toxoid universal CD4(+) T cell epitope P2 was introduced into P or P?VP8* construct. The resulting recombinant fusion proteins expressed in Escherichia coli were of high solubility and were produced with high yield. Two doses (10 or 20?g/dose) of the P2-P?VP8* vaccine or P2-P?VP8* vaccine with aluminum phosphate adjuvant elicited significantly higher geometric mean homologous neutralizing antibody titers than the vaccines without P2 in intramuscularly immunized guinea pigs. Interestingly, high levels of neutralizing antibody responses induced in guinea pigs with 3 doses of the P2-P?VP8* vaccine persisted for at least 6 months. Furthermore, in the gnotobiotic piglet challenge study, three intramuscular doses (50?g/dose) of the P2-P?VP8* vaccine with aluminum phosphate adjuvant significantly delayed the onset of diarrhea and significantly reduced the duration of diarrhea and the cumulative diarrhea score after oral challenge with virulent human rotavirus Wa (G1P) strain. The P2-P?VP8* vaccine induced serum virus neutralizing antibody and VP4-specific IgG antibody production prechallenge, and primed the pigs for higher antibody and intestinal and systemic virus-specific IFN-? producing CD4(+) T cell responses postchallenge. These two subunit vaccines could be used at a minimum singly or preferably in bivalent formulation to provide antigenic coverage of most of the G types of global importance. PMID:24962749
Wen, Xiaobo; Wen, Ke; Cao, Dianjun; Li, Guohua; Jones, Ronald W; Li, Jianping; Szu, Shousun; Hoshino, Yasutaka; Yuan, Lijuan
Because inactivated poliovirus vaccine (IPV) and Haemophilus influenzae b vaccine are advised in many programs and may be incorporated further in other programs, we undertook a study to determine whether the administration of a tetravalent preparation of diphtheria-tetanus-pertussis-IPV mixed in one syringe with tetanus-conjugate H. influenzae b vaccine (DTP-IPV-PRPT) is associated with increased reactogenicity or interference with immunogenicity of individual vaccine components. In a placebo-controlled, double blind study, a total of 161 infants were enrolled (80 DTP-IPV-PRPT and 81 DTP-IPV-placebo). Vaccine was administered at 2, 4 and 6 months of age. Oral poliovirus vaccine was added at 7 months of age and a booster of oral poliovirus vaccine and DTP-IPV was also administered at 12 months of age, according to the policy in Israel. Local and systemic side effects were similar in both groups except for irritability after the second dose and use of acetaminophen which we observed slightly but significantly more often in the DTP-IPV-PRPT recipients. After the third dose the geometric mean titers of anti-polyribosyl-ribitol phosphate antibodies were 3.7 and 0.05 micrograms/ml in the PRPT and placebo groups, respectively (P < 0.001). Higher tetanus antitoxin titers were observed among recipients of DPT-IPV-placebo (1.1 IU/ml vs. 0.7 IU/ml, P = 0.003). A similar trend was found for pertussis agglutinin titers (93.4 vs. 65.4, P = 0.054). No difference was observed for anti-diphtheria toxoid and poliovirus 1, 2, and 3.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8072816
Dagan, R; Botujansky, C; Watemberg, N; Arbelli, Y; Belmaker, I; Ethevenaux, C; Fritzell, B
Glycoconjugate vaccines have been proven safe and effective against various diseases in children. Although these vaccines have a history of effectiveness, there are still many unanswered questions to be addressed, including conjugate interference when multiple vaccines are administered at one time, expansion of serotype coverage, effectiveness in special populations, and issues relating to conjugate vaccine use in the developing world.
Henry R. Shinefield
Vaccination against the highly abused prescription opioid oxycodone has shown pre-clinical efficacy for blocking oxycodone effects. The current study further evaluated a candidate vaccine composed of oxycodone derivatized at the C6 position (6OXY) conjugated to the native keyhole limpet hemocyanin (nKLH) carrier protein. To provide an oxycodone vaccine formulation suitable for human studies, we studied the effect of alternative carriers and adjuvants on the generation of oxycodone-specific serum antibody and B cell responses, and the effect of immunization on oxycodone distribution and oxycodone-induced antinociception in mice and rats. 6OXY conjugated to tetanus toxoid (TT) or a GMP grade KLH dimer (dKLH) was as effective as 6OXY conjugated to the nKLH decamer in mice and rats, while the 6OXY hapten conjugated to a TT-derived peptide was not effective in preventing oxycodone-induced antinociception in mice. Immunization with 6OXY-TT s.c. absorbed on alum adjuvant provided similar protection to 6OXY-TT administered i.p. with Freund's adjuvant in rats. The toll-like receptor 4 (TLR4) agonist monophosphoryl lipid A (MPLA) adjuvant, alone or in combination with alum, offered no advantage over alum alone for generating oxycodone-specific serum antibodies or 6OXY-specific antibody secreting B cells in mice vaccinated with 6OXY-nKLH or 6OXY-TT. The immunogenicity of oxycodone vaccines may be modulated by TLR4 signaling since responses to 6OXY-nKLH in alum were decreased in TLR4-deficient mice. These data suggest that TT, nKLH and dKLH carriers provide consistent 6OXY conjugate vaccine immunogenicity across species, strains and via different routes of administration, while adjuvant formulations may need to be tailored to individual immunogens or patient populations. PMID:24797666
Pravetoni, Marco; Vervacke, Jeffrey S; Distefano, Mark D; Tucker, Ashli M; Laudenbach, Megan; Pentel, Paul R
Vaccination against the highly abused prescription opioid oxycodone has shown pre-clinical efficacy for blocking oxycodone effects. The current study further evaluated a candidate vaccine composed of oxycodone derivatized at the C6 position (6OXY) conjugated to the native keyhole limpet hemocyanin (nKLH) carrier protein. To provide an oxycodone vaccine formulation suitable for human studies, we studied the effect of alternative carriers and adjuvants on the generation of oxycodone-specific serum antibody and B cell responses, and the effect of immunization on oxycodone distribution and oxycodone-induced antinociception in mice and rats. 6OXY conjugated to tetanus toxoid (TT) or a GMP grade KLH dimer (dKLH) was as effective as 6OXY conjugated to the nKLH decamer in mice and rats, while the 6OXY hapten conjugated to a TT-derived peptide was not effective in preventing oxycodone-induced antinociception in mice. Immunization with 6OXY-TT s.c. absorbed on alum adjuvant provided similar protection to 6OXY-TT administered i.p. with Freund’s adjuvant in rats. The toll-like receptor 4 (TLR4) agonist monophosphoryl lipid A (MPLA) adjuvant, alone or in combination with alum, offered no advantage over alum alone for generating oxycodone-specific serum antibodies or 6OXY-specific antibody secreting B cells in mice vaccinated with 6OXY-nKLH or 6OXY-TT. The immunogenicity of oxycodone vaccines may be modulated by TLR4 signaling since responses to 6OXY-nKLH in alum were decreased in TLR4-deficient mice. These data suggest that TT, nKLH and dKLH carriers provide consistent 6OXY conjugate vaccine immunogenicity across species, strains and via different routes of administration, while adjuvant formulations may need to be tailored to individual immunogens or patient populations.
Pravetoni, Marco; Vervacke, Jeffrey S.; Distefano, Mark D.; Tucker, Ashli M.; Laudenbach, Megan; Pentel, Paul R.
Shigella flexneri type 2a lipopolysaccharide (LPS) was detoxified with acetic acid (O-SP) or with hydrazine (DeALPS). DeALPS, but not O-SP, retained part of its lipid A. Both gave an identical line of precipitation with typing antiserum by double immunodiffusion, and both had low levels of LPS activity by the Limulus amoebocyte lysate assay. O-SP had an M(r) of approximately 17,000. DeALPS had two components of M(r)s approximately 30,00 (major and approximately 10,000 (minor). Adipic acid hydrazide derivatives of O-SP and DeALPS were conjugated to tetanus toxoid (TT), purified by gel filtration through CL-6B Sepharose, and designated O-SP-TT and DeALPS-TT, respectively. Saccharide (2.5 micrograms) as O-SP, DeALPS, or their conjugates was injected subcutaneously into 5-week-old mice three times 2 weeks apart. The mice were bled before the second injection and 7 days after the second and third. O-SP alone did not elicit immunoglobulin M (IgM) or IgG LPS antibodies. DeALPS elicited low levels of IgM LPS antibodies after the third injection only. Two of three lots of O-SP-TT induced significant levels of IgM LPS antibodies after the third injection. One O-SP-TT lot elicited IgG LPS antibodies after the second injection, and all three lots elicited significant levels of IgG after the third. DeALPS-TT induced low levels of anti-LPS IgM and IgG only after the third injection. The geometric mean antibody titers of both immunoglobulin classes induced by O-SP-TT were higher than those induced by DeALPS-TT. By these criteria, O-SP provided a more immunogenic saccharide than DeALPS for S. flexneri type 2a conjugates. Images
Polotsky, V Y; Robbins, J B; Bryla, D; Schneerson, R
NCI Scientists have discovered that conjugating CpG ODNs to apoptotic tumor cells to improve vaccine activity by ensuring that the ODN remains associated with the tumor antigen so that both are internalized by professional antigen presenting cells. The strategy eliminates the need to define specific tumor-associated antigens, substituting instead the entire tumor cell (which in the absence of CpG ODN is poorly immunogenic).
Streptococcus group B (GBS) is usually carried asymptomatically in the vaginal tract of women and can be transferred to the newborn during parturition. Serum antibodies to the capsular polysaccharide (CPS) can prevent invasive diseases, whereas immunity acting at the mucosal surface may be more important to inhibit the mucosal colonization of GBS and thus the risk of infection for the newborn. We prepared different GBS type III CPS-protein conjugate vaccines and evaluated their systemic and mucosal immunogenicity in mice. GBS type III CPS was conjugated to tetanus toxoid (TT) or recombinant cholera toxin B subunit (rCTB) either directly or to rCTB indirectly via TT. The conjugation was performed by different methods: (1) CPS was coupled to TT with 1-ethyl-3 (3-dimethylaminopropyl)-carbodiimide (EDAC), using adipic acid dihydrazide (ADH) as a spacer; (2) CPS was conjugated with rCTB using reductive amination; or, (3) N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) was used to bind rCTB to the TT of the CPS-TT conjugate. Mice were immunized with these conjugates or purified CPS by subcutaneous (s.c.) and intranasal (i. n.) routes. Antibodies to GBS III in serum, lungs and vagina were measured with ELISA. All of the CPS-protein conjugates were superior to unconjugated CPS in eliciting CPS-specific immune responses in serum and mucosal tissue extracts. The conjugates, when administrated s.c., induced only IgG responses in serum, lung and vagina, while i.n. vaccination also elicited IgA responses in the lungs and vagina. The CPS-TT conjugate administrated i.n. induced a strong serum IgG, but only a weak mucosal IgA response, while the CPS-rCTB conjugate elicited high IgG as well as IgA antibodies in the lungs after i.n. immunization. GBS III CPS-TT conjugated with rCTB produced a strong systemic and local anti-CPSIII response after i.n. administration. Co-administration of CT as adjuvant enhanced the anti-CPS systemic and mucosal immune responses further after i.n. administration with the CPS conjugates. These findings indicate that: (i) i.n. immunization with GBS CPS-protein conjugates was more effective than s.c immunization for stimulating serum as well as mucosal immune responses; (ii) rCTB as a carrier protein for GBS III CPS could markedly improve the mucosal immune response; and (iii) the experimental GBS type III CPS conjugates containing rCTB should be investigated as mucosal vaccine to prevent GBS infection in humans. PMID:11115709
Shen, X; Lagergård, T; Yang, Y; Lindblad, M; Fredriksson, M; Holmgren, J
RotaTeq (Merck & Co. Inc./Sanofi Pasteur MSD) is a three-dose, oral pentavalent rotavirus vaccine for the immunization of infants from 6 weeks of age for the prevention of rotavirus gastroenteritis. The primary objective of the present trial was to demonstrate that RotaTeq can be coadministered with meningococcal serogroup C conjugate vaccine (MenCC; NeisVac-C; Baxter Healthcare) to healthy infants without impairing the protective immune responses to MenCC. This was an open-label, randomized, comparative study conducted in Finland. The study was designed to assess concomitant versus sequential administration of RotaTeq and MenCC on the immune response to both vaccines. Healthy infants (n = 247), aged 6 to 7 weeks, were recruited. Coadministration of MenCC with RotaTeq was noninferior to sequential administration for the seroprotection rate against meningococcal serogroup C (the proportion of infants with a serum bactericidal antibody titer using baby rabbit complement of ?8 was 100% in both groups). The other responses to MenCC (titer of ?1:128, ?4-fold increase in titer, and geometric mean titers [GMTs]) and the responses to RotaTeq (IgA and SNA response to G1 to G4 and P1A, GMTs, and ?3-fold increase in titer) were comparable between groups, including a ?3-fold IgA increase in >96% of the infants in both groups. Concomitant administration of the first doses of MenCC, diphtheria and tetanus toxoids and acellular pertussis vaccine, inactivated poliovirus vaccine, and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV-Hib), and RotaTeq was associated with a higher rate of vomiting and diarrhea than concomitant administration of MenCC and DTaP-IPV-Hib, but that was not observed after the second concomitant administration. The convenience of concomitant administration of RotaTeq and MenCC may, however, outweigh the additive effect of mostly mild adverse events reported after the individual administration of each vaccine. These results support the coadministration of RotaTeq and MenCC.
Vesikari, Timo; Karvonen, Aino; Borrow, Ray; Kitchin, Nick; Baudin, Martine; Thomas, Stephane; Fiquet, Anne
The increasing frequency, severity and antimicrobial resistance of Staphylococcus aureus infections has made the development of immunotherapies against this pathogen more urgent than ever. Previous immunization attempts using monovalent antigens resulted in at best partial levels of protection against S. aureus infection. We therefore reasoned that synthesizing a bivalent conjugate vaccine composed of two widely expressed antigens of S. aureus would result in additive/synergetic activities by antibodies to each vaccine component and/or in increased strain coverage. For this we used reductive amination, to covalently link the S. aureus antigens clumping factor A (ClfA) and deacetylated poly-N-?-(1–6)-acetyl-glucosamine (dPNAG). Mice immunized with 1, 5 or 10 µg of the dPNAG-ClfA conjugate responded in a dose-dependent manner with IgG to dPNAG and ClfA, whereas mice immunized with a mixture of ClfA and dPNAG developed significantly lower antibody titers to ClfA and no antibodies to PNAG. The dPNAG-ClfA vaccine was also highly immunogenic in rabbits, rhesus monkeys and a goat. Moreover, affinity-purified, antibodies to ClfA from dPNAG-ClfA immune serum blocked the binding of three S. aureus strains to immobilized fibrinogen. In an opsonophagocytic assay (OPKA) goat antibodies to dPNAG-ClfA vaccine, in the presence of complement and polymorphonuclear cells, killed S. aureus Newman and, to a lower extent, S. aureus Newman ?clfA. A PNAG-negative isogenic mutant was not killed. Moreover, PNAG antigen fully inhibited the killing of S. aureus Newman by antisera to dPNAG-ClfA vaccine. Finally, mice passively vaccinated with goat antisera to dPNAG-ClfA or dPNAG-diphtheria toxoid conjugate had comparable levels of reductions of bacteria in the blood 2 h after infection with three different S. aureus strains as compared to mice given normal goat serum. In conclusion, ClfA is an immunogenic carrier protein that elicited anti-adhesive antibodies that fail to augment the OPK and protective activities of antibodies to the PNAG cell surface polysaccharide.
Bozkurt-Guzel, Cagla; O'Malley, Jennifer M.; Cywes-Bentley, Colette; Pier, Gerald B.
Research on the conjugates of synthetic polyelectrolytes with antigenic molecules, such as proteins, peptides, or carbohydrates, is an attractive area due to their highly immunogenic character in comparison to classical adjuvants. For example, polyacrylic acid (PAA) is a weak polyelectrolyte and has been used in several biomedical applications such as immunological studies, drug delivery, and enzyme immobilization. However, to our knowledge, there are no studies that document immune-stimulant properties of PAA in Leishmania infection. Therefore, we aimed to develop a potential vaccine candidate against leishmaniasis by covalently conjugating PAA with an immunologically vital molecule of lipophosphoglycan (LPG) found in Leishmania parasites. In the study, LPG and PAA were conjugated by a multi-step procedure, and final products were analyzed with GPC and MALDI-TOF MS techniques. In cytotoxicity experiments, LPG-PAA conjugates did not indicate toxic effects on L929 and J774 murine macrophage cells. We assume that LPG-PAA conjugate can be a potential vaccine candidate, and will be immunologically characterized in further studies to prove its potential.
7vCRM (Pfizer, Inc.) and PHiD-CV (GlaxoSmithKline Biologicals) are two pneumococcal conjugate vaccines licensed for the prevention of invasive pneumococcal disease and acute otitis media caused by the vaccine serotypes of Streptococcus pneumoniae. Neither vaccine contains serotype 19A, but both contain the closely related serotype 19F. No decrease in the incidence of serotype 19A disease has been observed following the introduction of 7vCRM, suggesting that this serotype 19F-containing vaccine provides limited cross-protection against serotype 19A. To investigate the impact that conjugation methods may have on antipolysaccharide immune responses and to determine whether this limited cross-protection is characteristic of the serotype 19F polysaccharide or rather of the 19F-CRM (cross-reacting material) conjugate, we compared naturally induced antibodies against serotypes 19F and 19A with antibodies induced after vaccination with different pneumococcal conjugate vaccines. We found that conjugation of the serotype 19F polysaccharide using reductive amination (as in 7vCRM) resulted in the formation of at least one additional epitope that is not present in the native form of the 19F polysaccharide or following 19F conjugation using a bifunctional spacer (as in the prototype vaccine 7vOMPC) or cyanylation (as in PHiD-CV). We also found that pneumococcal vaccines conjugated using cyanylation induce more opsonophagocytic antibodies against serotype 19F and a considerably higher level of cross-opsonophagocytic antibodies against serotype 19A than vaccines conjugated using reductive amination. In conclusion, these results suggest that the conjugation method can influence the functionality of the antibodies induced against the homologous serotype 19F and the cross-reactive serotype 19A of S. pneumoniae.
Poolman, Jan; Frasch, Carl; Nurkka, Anu; Kayhty, Helena; Biemans, Ralph; Schuerman, Lode
In the first 2 years after nationwide implementation (2006-2008), the pneumococcal conjugate vaccination proved to be highly effective in reducing invasive pneumococcal disease caused by vaccine serotypes in the vaccinated children. However, the rapid increase in non-vaccine serotype IPD reduced the net vaccine benefit. These emerging non-vaccine serotypes are also invasive and result in serious burden of disease. Pneumococcal disease
G. D. Rodenburg
Affinity tags can interfere in various physicochemical properties and immunogenicity of the recombinant proteins. In the present study, tag-free recombinant fusion protein encompassing promiscuous T cell epitope of tetanus toxoid [TT; amino acid (aa) residues 830-844] followed by dilysine linker and dog zona pellucida glycoprotein-3 (ZP3; aa residues 23-348) (TT-KK-ZP3) was expressed in Escherichia coli. The recombinant protein, expressed as inclusion bodies (IBs), was purified by isolation of IBs, processed to remove host cell proteins, followed by solubilization and refolding. A specific 39 kDa protein including ZP3 was identified by SDS-PAGE. CD spectra showed the presence of ?-helices and ?-sheets, and fluorescent spectroscopy revealed emission maxima of 265 A.U. at 339 nm for refolded protein and showed red shift in the presence of 6 M guanidine hydrochloride. Immunization of inbred FvB/J female mice with purified recombinant TT-KK-ZP3 (25 ?g/animal) led to generation of high antibody titers against the recombinant protein. The antibodies reacted specifically with ZP matrix surrounding mouse oocytes. Immunized mice showed significant reduction in fertility as compared to the control group. The studies described herein provide a simple method to produce and purify tag-free recombinant protein for the development of a contraceptive vaccine. PMID:23242635
Gupta, Neha; Shrestha, Abhinav; Panda, Amulya Kumar; Gupta, Satish Kumar
Background Gambia is the second GAVI support-eligible country to introduce the 7-valent pneumococcal conjugate vaccine (PCV7), but a country-specific cost-effectiveness analysis of the vaccine is not available. Our objective was to assess the potential impact of PCVs of different valences in The Gambia. Methods We synthesized the best available epidemiological and cost data using a state-transition model to simulate the natural histories of various pneumococcal diseases. For the base-case, we estimated incremental cost (in 2005 US dollars) per disability-adjusted life year (DALY) averted under routine vaccination using PCV9 compared to no vaccination. We extended the base-case results for PCV9 to estimate the cost-effectiveness of PCV7, PCV10, and PCV13, each compared to no vaccination. To explore parameter uncertainty, we performed both deterministic and probabilistic sensitivity analyses. We also explored the impact of vaccine efficacy waning, herd immunity, and serotype replacement, as a part of the uncertainty analyses, by assuming alternative scenarios and extrapolating empirical results from different settings. Results Assuming 90% coverage, a program using a 9-valent PCV (PCV9) would prevent approximately 630 hospitalizations, 40 deaths, and 1000 DALYs, over the first 5 years of life of a birth cohort. Under base-case assumptions ($3.5 per vaccine), compared to no intervention, a PCV9 vaccination program would cost $670 per DALY averted in The Gambia. The corresponding values for PCV7, PCV10, and PCV13 were $910, $670, and $570 per DALY averted, respectively. Sensitivity analyses that explored the implications of the uncertain key parameters showed that model outcomes were most sensitive to vaccine price per dose, discount rate, case-fatality rate of primary endpoint pneumonia, and vaccine efficacy against primary endpoint pneumonia. Conclusions Based on the information available now, infant PCV vaccination would be expected to reduce pneumococcal diseases caused by S. pneumoniae in The Gambia. Assuming a cost-effectiveness threshold of three times GDP per capita, all PCVs examined would be cost-effective at the tentative Advance Market Commitment (AMC) price of $3.5 per dose. Because the cost-effectiveness of a PCV program could be affected by potential serotype replacement or herd immunity effects that may not be known until after a large scale introduction, type-specific surveillance and iterative evaluation will be critical.
... Name Sanofi Pasteur, Ltd Diphtheria & Tetanus Toxoids & Acellular Pertussis Vaccine Adsorbed Tripedia Sanofi Pasteur, Inc (not available) Diphtheria & Tetanus Toxoids & Acellular Pertussis Vaccine Adsorbed Infanrix GlaxoSmithKline Biologicals Diphtheria & Tetanus Toxoids & ...
The influence of preexisting immunity on the heavy-chain isotypes of circulating antibody-secreting cells (AbSC) induced by vaccination with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to tetanus toxoid (TT) or diphtheria toxoid (DT) and by vaccination with TT or DT alone in 51 healthy adults and 9 infants was studied. In adults, the isotypes of TT and DT AbSC were dominated by immunoglobulin G1 (IgG1) followed by IgG4 and IgA1. HibCP AbSC were dominated by the isotype IgA1 followed by (in decreasing order) IgG2, IgA2, IgM, and IgG1. The isotype distributions of TT and DT AbSC were independent of whether the toxoids were coupled to HibCP, and the isotypes of HibCP AbSC were not influenced by the nature of the carrier (TT or DT). Furthermore, the isotype distributions were unaffected by recent immunization with components of the conjugates, although this reduced the numbers of AbSC. The heavy-chain gene usage of HibCP AbSC in adults differed clearly from that in infants, which was restricted largely to the genes mu, gamma 1, and alpha 1, all lying upstream in the heavy-chain constant-region gene locus, while the usage in adults also, to different extents, involved the downstream genes gamma 2 and alpha 2. The ratio between the numbers of HibCP AbSC using heavy-chain genes from the downstream duplication unit (gamma 2, gamma 4, and alpha 2) and those using genes from the upstream duplication unit (gamma 3, gamma 1, and alpha 1) correlated with the preimmunization level of natural HibCP antibodies (r = 0.59; P = 0.00002). A possible role of natural exposure for Hib or cross-reactive bacteria on the mucosal surfaces in the shaping of the isotype response to HibCP conjugate vaccines is discussed.
Barington, T; Juul, L; Gyhrs, A; Heilmann, C
A prospective study to evaluate immune status against diphtheria and immunologic response after tetanus-diphtheria (Td) booster vaccination was conducted in 250 Thai health care workers (HCWs). A protective antibody was found in 89.2% of the HCWs (95% confidence interval [CI], 83.3%-91.5%) before receipt of the Td booster vaccination, compared with 97.2% (95% CI, 95.1%-99.3%) after receipt of the first dose of booster (P < .001). The mean antibody level against diphtheria increased from 0.39 IU/mL (95% CI, 0.35-0.44 IU/mL) before the Td booster vaccination to 1.20 IU/mL (95% CI, 1.12-1.29 IU/mL) after the vaccination (P < .001). Td booster vaccination should be considered for Thai HCWs to maintain immunity against diphtheria, which still circulates in Thailand. PMID:24751139
Wiboonchutikul, Surasak; Manosuthi, Weerawat; Sangsajja, Chariya; Thientong, Varaporn; Likanonsakul, Sirirat; Srisopha, Somkid; Termvises, Patamavadee; Rujitip, Jitlada; Loiusirirotchanakul, Suda; Puthavathana, Pilaipan
While pneumococcal conjugate vaccines have shown to be highly effective against invasive pneumococcal disease, their potential effectiveness against acute otitis media (AOM) might become a major economic driver for implementing these vaccines in national immunization programmes. However, the relationship between the costs and benefits of available vaccines remains a controversial topic. Our objective is to systematically review the literature on
Chantal W. B. Boonacker; Pieter H. Broos; Elisabeth A. M. Sanders; Anne G. M. Schilder; Maroeska M. Rovers
Typhoid fever remains a serious problem in developing countries. Current vaccines are licensed for individuals who are 5 years old or older. A conjugate of the capsular polysaccharide (CP) of Salmonella enterica serovar Typhi (Vi) bound to recombinant exoprotein A of Pseudomonas aeruginosa (Vi-rEPA) enhanced Vi immunogenicity and protected 2- to 5-year-olds in Vietnam. In this study, Vi-rEPA was evaluated for use in infants. A total of 301 full-term Vietnamese infants received Expanded Program on Immunization (EPI) vaccines alone or with Vi-rEPA or Haemophilus influenzae type b-tetanus toxoid conjugate (Hib-TT) at 2, 4, and 6 months and Vi-rEPA or Hib-TT alone at 12 months. Infants were visited 6, 24, and 48 h after each injection to monitor adverse reactions. Maternal, cord, and infant sera were assayed for IgG anti-Vi and for IgG antibodies to Hib CP and the diphtheria, tetanus, and pertussis toxins at 7, 12, and 13 months. No vaccine-related serious adverse reactions occurred. In the Vi-rEPA group, the IgG anti-Vi geometric mean (GM) increased from the cord level of 0.66 to 17.4 enzyme-linked immunosorbent assay units (EU) at 7 months, declined to 4.76 EU at 12 months, and increased to 50.1 EU 1 month after the 4th dose (95% of infants had levels of ?3.5 EU, the estimated protective level). Controls had no increase of the IgG anti-Vi GM. Infants with cord anti-Vi levels of <3.5 EU responded with significantly higher IgG anti-Vi levels than those with levels of ?3.5 EU. Anti-diphtheria, -tetanus, and -pertussis toxin levels were similar in all groups. Vi-rEPA was safe, induced protective anti-Vi levels, and was compatible with EPI vaccines, and it can be used in infants. High cord IgG anti-Vi levels partially suppressed infant responses to Vi-rEPA.
Thiem, Vu Dinh; Lin, Feng-Ying C.; Canh, Do Gia; Son, Nguyen Hong; Anh, Dang Duc; Mao, Nguyen Duc; Chu, Chiayung; Hunt, Steven W.; Robbins, John B.; Schneerson, Rachel; Szu, Shousun C.
A seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the Danish childhood immunization program (2+1 schedule) in October 2007, followed by PCV13 starting from April 2010. The nationwide incidence of IPD among children younger than 5 years nearly halved after the introduction of PCV7 in the program, mainly due to a decline in IPD caused by PCV7-serotypes. We report the results from a nationwide population-based cohort study of laboratory confirmed IPD cases in children younger than 5 years during October 1, 2007 to December 31, 2010 and describe the characteristics of children suspected to present with a vaccine failure. The period between April 19 and December 31, 2010 was considered a PCV7/PCV13 transitional period, where both vaccines were offered. We identified 45 episodes of IPD caused by a PCV7 serotype (23% of the total number) and 105 (55%) caused by one of the 6 additional serotypes in PCV13. Ten children had received at least one PCV7 dose before the onset of IPD caused by a PCV7 serotype. Seven children were considered to be incompletely vaccinated before IPD, but only three cases fulfilled the criteria of vaccine failure (caused by serotypes 14, 19F and 23F). One case of vaccine failure was observed in a severely immunosuppressed child following three PCV7 doses, and two cases were observed in immunocompetent children following two infant doses before they were eligible for their booster. None of the IPD cases caused by the additional PCV13 serotypes had been vaccinated by PCV13 and there were therefore no PCV13-vaccine failures in the first 8-months after PCV13 introduction in Denmark. PMID:23365635
Harboe, Zitta B; Valentiner-Branth, Palle; Ingels, Helene; Rasmussen, Jeppe N; Andersen, Peter H S; Bjerre, Catherine C; Goldblatt, David; Ashton, Lindsey; Haston, Mitch; Konradsen, Helle B; Lambertsen, Lotte
OBJECTIVES: To assess the safety and tolerability of 12 lots of SmithKline Beecham Biologicals' diphtheria-tetanus-tricomponent acellular pertussis vaccine (DTaP) in a large cohort of 22,000 vaccinees, with detailed analyses of reactivity, immunogenicity, and immune response to pertussis toxin in subsets. METHODS: In a prospective, double-blind, multicenter trial in Germany, 22,505 healthy infants received three vaccinations of DTaP at age 3,
Heinz J. Schmitt; Anne Schuind; Markus Knuf; Karin Beutel; Hermann Schulte-Wissermann; Manfred Gahr; Rainer Schult; Jens Folkens; Wolfgang Rauh; Hugues Bogaerts; Hans L. Bork; Ralf Clemens
Invasive pneumococcal disease in adults may be declining, reflecting a form of herd protection from a new pediatric pneumococcal conjugate vaccine. Our aim was to determine whether vaccination of children protects adults in the same home from bacteremic pneumococcal pneumonia. We conducted a case–control study with 43 participating hospitals across a five-county region in Pennsylvania. Eligible cases were adults with
Joshua P. Metlay; Neil O. Fishman; Marshall Joffe; Paul H. Edelstein
Analysis of the impact of a vaccine for an infectious disease is an indirect approach to the evaluation of the importance of the disease when the diagnosis is difficult. Streptocccus pneumoniae is the most important cause of severe pneumonia. Pneumococcal conjugate vaccine (PnCV) may be used as a probe to define the burden of pneumococcal disease and better characterize the
To estimate cost-effectiveness of routine and catch-up vaccination of Canadian children with seven-valent pneumococcal conjugate vaccine, a simulation model was constructed. In base scenario (vaccination coverage: 80%, and vaccine price: $58 per dose), pneumococcal disease incidence reduction would be superior to 60% for invasive infections, and to 30% for non-invasive infections, but the number of deaths prevented would be small.
Philippe De Wals; Geneviève Petit; Lonny James Erickson; Maryse Guay; Theresa Tam; Barbara Law; Alicia Framarin
...2009-01-01 false Clostridium Perfringens Type D Toxoid and Bacterin-Toxoid...Products Â§ 113.112 Clostridium Perfringens Type D Toxoid and Bacterin-Toxoid. Clostridium Perfringens Type D Toxoid and Clostridium...
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...2010-01-01 false Clostridium Perfringens Type D Toxoid and Bacterin-Toxoid...Products Â§ 113.112 Clostridium Perfringens Type D Toxoid and Bacterin-Toxoid. Clostridium Perfringens Type D Toxoid and Clostridium...
...2010-01-01 false Clostridium Perfringens Type C Toxoid and Bacterin-Toxoid...Products Â§ 113.111 Clostridium Perfringens Type C Toxoid and Bacterin-Toxoid. Clostridium Perfringens Type C Toxoid and Clostridium...
Mechanisms to increase access to health products are varied and controversial. Two innovative mechanisms have been used to accelerate the development of low-price supply lines for conjugate vaccines. The Meningitis Vaccine Project is a so-called push mechanism that facilitated technology transfer to an Indian company to establish capacity to manufacture a vaccine. The Advanced Market Commitment for pneumococcal vaccines is a so-called pull mechanism that guarantees companies a supplement paid in addition to the purchase price for vaccines for a specific period. We compare these approaches, identifying key dimensions of each and considering their potential for replication. We also discuss issues that the Global Alliance for Vaccines and Immunisation (GAVI) face now that these new vaccines are available. Progress towards GAVI's strategic aims is needed and funding is crucial. Approaches that decrease the financial pressure on GAVI and greatly increase political and financial engagement by low-income countries should also be considered. PMID:21664678
Hargreaves, James R; Greenwood, Brian; Clift, Charles; Goel, Akshay; Roemer-Mahler, Anne; Smith, Richard; Heymann, David L
The generation of effective immune responses by mucosal vaccination without the use of inflammatory adjuvants, that compromise the epithelial barrier and recruit new cellular targets, is a key goal of vaccines designed to protect against sexually acquired pathogens. In the present study we use a model HIV antigen (CN54gp140) conjugated to transferrin (Tf) and evaluate the ability of the natural transferrin receptor CD71 to modulate immunity. We show that the conjugated transferrin retained high affinity for its receptor and that the conjugate was specifically transported across an epithelial barrier, co-localizing with MHC Class II+ cells in the sub-mucosal stroma. Vaccination studies in mice revealed that the Tf-gp140 conjugate elicited high titres of CN54gp140-specific serum antibodies, equivalent to a systemic vaccination, when conjugate was applied topically to the nasal mucosae whereas gp140 alone was poorly immunogenic. Moreover, the Tf-gp140 conjugate elicited both IgG and IgA responses and significantly higher gp140-specific IgA titre in the female genital tract than unconjugated antigen. These responses were achieved after mucosal application of the conjugated protein alone, in the absence of any pro-inflammatory adjuvant and suggest a potentially useful and novel molecular targeting approach, delivering a vaccine cargo to directly elicit or enhance pathogen-specific mucosal immunity.
Mann, J.F.S.; Stieh, D.; Klein, K.; de Stegmann, D.S. Miranda; Cranage, M.P.; Shattock, R.J.; McKay, P.F.
Safety, tolerability, and immunologic noninferiority of a 13-valent pneumococcal conjugate vaccine compared to a 7-valent pneumococcal conjugate vaccine given with routine pediatric vaccinations in Germany
13-valent pneumococcal conjugate vaccine (PCV13) was compared to PCV7 in infants administered 4 doses. For the 7 common serotypes, PCV13- and PCV7-elicited responses showed comparable percent responders achieving 0.35?g\\/mL IgG threshold (exception 6B, 77.5% versus 87.1%, respectively) and OPA titers of 1:8; IgGs were lower than PCV7 but functional responses were generally comparable. For the 6 additional serotypes, PCV13-elicited IgG
Dorothee M. Kieninger; Kathrin Kueper; Katrin Steul; Christine Juergens; Norbert Ahlers; Sherryl Baker; Kathrin U. Jansen; Carmel Devlin; William C. Gruber; Emilio A. Emini; Daniel A. Scott
Streptococcus pneumoniae is a common cause of respiratory tract infections, its main entry route being the nasal mucosa. The recent development of pneumococcal polysaccharide conjugate vaccines has led to a dramatic improvement in protection against invasive disease in infants and children, but these vaccines have been found to be only 50 to 60% protective against bacterial carriage. In this study,
Joyce M. Lynch; David E. Briles; Dennis W. Metzger
This paper describes the development of a Haemophilus influenzae type b (Hib) conjugate vaccine at the National Institute for Public Health and the Environment/Netherlands Vaccine Institute (RIVM/NVI, Bilthoven, The Netherlands), and the subsequent transfer of its production process to manufacturers in developing countries. In 1998, at the outset of the project, the majority of the world's children were not immunized against Hib because of the high price and limited supply of the conjugate vaccines, due partly to the fact that local manufacturers in developing countries did not master the Hib conjugate production technology. To address this problem, the RIVM/NVI has developed a robust Hib conjugate vaccine production process based on a proven model, and transferred this technology to several partners in India, Indonesia, Korea and China. As a result, emerging manufacturers in developing countries acquired modern technologies previously unavailable to them. This has in turn facilitated their approach to producing other conjugate vaccines. As an additional spin-off from the project, a World Health Organization (WHO) Hib quality control (QC) course was designed and conducted at the RIVM/NVI, resulting in an increased regulatory capacity for conjugate vaccines in developing countries at the National Regulatory Authority (NRA) level. For the local populations, this has translated into an increased and sustainable supply of affordable Hib conjugate-containing combination vaccines. During the course of this project, developing countries have demonstrated their ability to produce large quantities of high-quality modern vaccines after a successful transfer of the technology. PMID:22683521
Beurret, Michel; Hamidi, Ahd; Kreeftenberg, Hans
Polysaccharide-protein conjugates as vaccines have proven to be very effective in preventing Haemophilus influenzae type b infections in industrialized countries. However, cost-effective technologies need to be devel- oped for increasing the availability of anti-H. influenzae type b vaccines in countries from the developing world. Consequently, vaccine production with partially synthetic antigens is a desirable goal for many reasons. They may
V. Fernandez-Santana; F. Cardoso; A. Rodriguez; T. Carmenate; L. Pena; Y. Valdes; E. Hardy; F. Mawas; L. Heynngnezz; M. C. Rodriguez; I. Figueroa; J. Chang; M. E. Toledo; A. Musacchio; I. Hernandez; M. Izquierdo; K. Cosme; R. Roy; V. Verez-Bencomo
Cohort and population models estimate vaccine impact on disease events, and yield different estimates in countries with different demographic compositions. We compared administration of the new 10-valent pneumococcal Haemophilus influenzae–protein D conjugate vaccine (PHiD-CV) with no vaccination in two countries, the United Kingdom (UK) and Mexico, using two modelling strategies: a cohort model and a population model. The cohort model
Baudouin Standaert; Nadia Demarteau; Sandra Talbird; Josephine Mauskopf
Group A meningococcal disease has been an important public health problem in sub-Saharan Africa for over a century. Outbreaks occur there annually, and large epidemics occur at intervals ranging between 8 and 12 y. The Meningitis Vaccine Project was established in 2001 with funding from the Gates Foundation with the goal of developing, testing, licensing, and introducing an affordable group A meningococcal conjugate vaccine into Africa. From 2003 to 2009 a monovalent group A conjugate vaccine, MenAfriVac(TM) , was developed at the Serum Institute of India, Ltd through an innovative public/private partnership. Preclinical studies of the new conjugate vaccine were completed in 2004 and a Phase 1 study began in India in 2005. Phase 2/3 studies in African 1-29 y olds were completed in 2009 showing the new meningococcal A conjugate vaccine to be as safe as currently licensed meningococcal polysaccharide vaccines, but much more immunogenic. After Indian market authorization (December 2009) and WHO prequalification (June 2010), MenAfriVac(TM) was introduced at public health scale using a single 10 µg dose in individuals 1-29 y of age in Burkina Faso, Mali, and Niger in December 2010. We summarize the laboratory and clinical studies leading to prequalification of MenAfriVac(TM). The 2011 epidemic season ended with no reported case of group A meningitis in vaccinated individuals. PMID:22495119
Frasch, Carl E; Preziosi, Marie-Pierre; LaForce, F Marc
Context Haemophilus influenzae type b (Hib) conjugate vaccine is not perceived as a public health priority in Africa because data on Hib disease burden and vaccine effectiveness are scarce. Hib immunization was introduced in Kenyan infants in 2001. Objective to define invasive Hib disease incidence and Hib vaccine program effectiveness. Design, Setting, Patients culture-based surveillance for invasive Hib disease at Kilifi District Hospital from 2000 to 2005 was linked to demographic surveillance of 38,000 children aged <5 years in Kilifi District, Kenya. HIV infection and Hib vaccination status were determined for children with Hib disease admitted 2002–2005. Interventions Conjugate Hib vaccine within the routine childhood immunization program at ages 6, 10 and 14 weeks from November 2001 Main outcome measures Incidence of culture-proven Hib invasive disease before and after vaccine introduction and vaccine program effectiveness (1-incidence rate ratio) Results Prior to vaccine introduction the median age of Hib cases was 8 months; case fatality was 23%. Among children aged <5 years the annual incidence of invasive Hib disease 1 year before and 1 and 3 years after vaccine introduction was 66, 47 and 7.6 per 100,000, respectively. For children <2 years, incidence was 119, 82 and 16, respectively. In 2004–2005 vaccine effectiveness was 88% (95% CI 73–96%) among children <5 years and 87% (95% CI 66–96%) among children <2 years. Of 53 Hib cases admitted during 2002–2005, 29 (55%) were age-ineligible to have received vaccine, 12 (23%) had not been vaccinated despite being eligible, and 12 (23%) had received ?2 doses of vaccine (2 were HIV-positive). Conclusions In Kenya, introduction of Hib vaccine into the routine childhood immunization program reduced Hib disease incidence among children aged <5 years to 12% of its baseline level. This impact was not observed until the third year after vaccine introduction.
Cowgill, Karen D.; Ndiritu, Moses; Nyiro, Joyce; Slack, Mary P. E.; Chiphatsi, Salome; Ismail, Amina; Kamau, Tatu; Mwangi, Isaiah; English, Mike; Newton, Charles R. J. C.; Feikin, Daniel R.; Scott, J. Anthony G.
Salmonella enterica serovar Paratyphi A O-specific polysaccharide (O-SP) was activated with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) and bound to tetanus toxoid (TT) with adipic acid dihydrazide as a linker (SPA-TT1) or directly (SPA-TT2). In mice, these two conjugates elicited high levels of immunoglobulin G (IgG) anti-lipopolysaccharide (LPS) in serum with bactericidal activity (E. Konadu, J. Shiloach, D. A. Bryla, J. B. Robbins, and S. C. Szu, Infect. Immun. 64:2709–2715, 1996). The safety and immunogenicity of the two conjugates were then evaluated sequentially in Vietnamese adults, teenagers, and 2- to 4-year-old children. None of the vaccinees experienced significant side effects, and all had preexisting LPS antibodies. At 4 weeks after injection, there were significant increases of the geometric mean IgG and IgM anti-LPS levels in the adults and teenagers: both conjugates elicited a greater than fourfold rise in the IgG anti-LPS level in serum in ?80% of the volunteers. SPA-TT2 elicited slightly higher, though not statistically significantly, levels of IgG anti-LPS than did SPA-TT1 in these age groups. Accordingly, only SPA-TT2 was evaluated in the 2- to 4-year-old children. On a random basis, one or two injections were administered 6 weeks apart to the children. No significant side effects were observed, and the levels of preexisting anti-LPS in serum were similar in children of all ages. A significant rise in the IgG anti-LPS titer was elicited by the first injection (P = 0.0001); a second injection did not elicit a booster response. Representative sera from all groups had bactericidal activity that could be adsorbed by S. enterica serovar Paratyphi A LPS.
Konadu, Edward Y.; Lin, Feng-Ying C.; Ho, Vo Anh; Thuy, Nguyen Thi Thanh; Van Bay, Phan; Thanh, Tran Cong; Khiem, Ha Ba; Trach, Dang Duc; Karpas, Arthur B.; Li, Jianping; Bryla, Dolores A.; Robbins, John B.; Szu, Shousun C.
Salmonella enterica serovar Paratyphi A O-specific polysaccharide (O-SP) was activated with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) and bound to tetanus toxoid (TT) with adipic acid dihydrazide as a linker (SPA-TT(1)) or directly (SPA-TT(2)). In mice, these two conjugates elicited high levels of immunoglobulin G (IgG) anti-lipopolysaccharide (LPS) in serum with bactericidal activity (E. Konadu, J. Shiloach, D. A. Bryla, J. B. Robbins, and S. C. Szu, Infect. Immun. 64:2709-2715, 1996). The safety and immunogenicity of the two conjugates were then evaluated sequentially in Vietnamese adults, teenagers, and 2- to 4-year-old children. None of the vaccinees experienced significant side effects, and all had preexisting LPS antibodies. At 4 weeks after injection, there were significant increases of the geometric mean IgG and IgM anti-LPS levels in the adults and teenagers: both conjugates elicited a greater than fourfold rise in the IgG anti-LPS level in serum in >/=80% of the volunteers. SPA-TT(2) elicited slightly higher, though not statistically significantly, levels of IgG anti-LPS than did SPA-TT(1) in these age groups. Accordingly, only SPA-TT(2) was evaluated in the 2- to 4-year-old children. On a random basis, one or two injections were administered 6 weeks apart to the children. No significant side effects were observed, and the levels of preexisting anti-LPS in serum were similar in children of all ages. A significant rise in the IgG anti-LPS titer was elicited by the first injection (P = 0.0001); a second injection did not elicit a booster response. Representative sera from all groups had bactericidal activity that could be adsorbed by S. enterica serovar Paratyphi A LPS. PMID:10678970
Konadu, E Y; Lin, F Y; Hó, V A; Thuy, N T; Van Bay, P; Thanh, T C; Khiem, H B; Trach, D D; Karpas, A B; Li, J; Bryla, D A; Robbins, J B; Szu, S C
Safety and Immunogenicity of a 13Valent Pneumococcal Conjugate Vaccine Compared to Those of a 7Valent Pneumococcal Conjugate Vaccine Given as a Three-Dose Series with Routine Vaccines in Healthy Infants and Toddlers
A 13-valent pneumococcal conjugate vaccine (PCV13) has been developed to improve protection against pneumococcal disease beyond that possible with the licensed 7-valent vaccine (PCV7). This study compared the safety and immunogenicity of PCV13 with those of PCV7 when given as part of the pediatric vaccination schedule recommended in Italy. A total of 606 subjects were randomly assigned to receive either
Susanna Esposito; Susan Tansey; Allison Thompson; Ahmad Razmpour; John Liang; Thomas R. Jones; Giuseppe Ferrera; Alessandro Maida; Gianni Bona; Caterina Sabatini; Lorenza Pugni; Emilio A. Emini; William C. Gruber; Daniel A. Scott; Nicola Principi
... 12–15 months of age. Children in this age range are at greatest risk for serious diseases caused by pneumococcal infection. PCV13 vaccine may also be recommended ... over age 65. There is a separate Vaccine Information Statement ...
Conjugate vaccines were prepared with S. aureus type 8 capsular polysaccharide (CP) using three carrier proteins: Pseudomonas aeruginosa exotoxin A (ETA), a non-toxic recombinant ETA (rEPA), and diphtheria toxoid (DTd). Adipic acid dihydrazide (ADH) or N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) was used as a spacer to link the CP to carrier protein. All conjugates gave a high immune response with a
Ali Fattom; Xiuru Li; Yun Hee Cho; Amy Burns; Abbas Hawwari; Sara E. Shepherd; Richard Coughlin; Scott Winston; Robert Naso
Pertussis toxin in its detoxified form is a major component of all current acellular pertussis vaccines. Here we report the membrane translocation and internalization activities of pertussis toxin and various pertussis toxoids using Chinese hamster ovary cells and confocal microscopy based on indirect immunofluorescence labeling. Chemically detoxified pertussis toxoids were able to translocate/internalize into cells at the concentration about 1,000 times higher than the native toxin. Pertussis toxoids detoxified with different procedures (glutaraldehyde, glutaraldehyde plus formaldehyde, hydrogen peroxide or genetic mutation) showed differences in fluorescence intensity under the same condition, indicating toxoids from different detoxification methods may have different translocation/internalization activities on cells.
Tan, Yajun; Fleck, Roland A.; Asokanathan, Catpagavalli; Yuen, Chun-Ting; Xing, Dorothy; Zhang, Shumin; Wang, Junzhi
A conjugate meningococcal vaccine against serogroup B/C consisting of capsular PS (polysaccharide) from serogroup C conjugated to OMV (outer membrane vesicle) from serogroup B would be a very useful vaccine in regions where there is a prevalence of both serogroups, for example in Brazil. For this purpose, the conjugation method that uses ADHy (adipic acid dihydrazide) as spacer and a carbodi-imide derivative, EDAC [1-ethyl-3-(3-dimethylaminopropyl)carbodi-imide], as catalyser was optimized looking for synthesis yield and maintenance of the antigenicity of both components. The best synthesis conditions preserving the vaccine immunogenicity resulted in a final yield of approx. 17%. Immunogenicity of the vaccine was highest when 10% of the sialic acid residues of the PS were occupied by the ADHy spacer. Sterilization of the conjugate by filtration through a 0.22-microm-pore-size membrane resulted in a low recovery of protein and PS (approximately 50%), although the vaccine immunogenicity was maintained. Using gamma irradiation on freeze-dried sample, it was possible to maintain the integrity of OMV structure and, consequently, its ability to induce bactericidal antibodies. PMID:16776648
Fukasawa, Lucila O; Schenkman, Rocilda P F; Perciani, Catia T; Carneiro, Sylvia M; Dias, Waldely O; Tanizaki, Martha M
The 7-valent pneumococcal conjugate vaccine (PCV7) has been shown to be highly cost-effective. The 13-valent pneumococcal conjugate vaccine (PCV13) offers seroprotection against six additional serotypes. A decision-analytic model was constructed to estimate direct medical costs and clinical effectiveness of PCV13 vaccination on invasive pneumococcal disease (IPD), pneumonia, and otitis media relative to PCV7 vaccination. The option with an one-dose catch-up vaccination in children of 15-59 months was also considered. Assuming 83% vaccination coverage and considering indirect effects, 1808 IPD, 5558 pneumonia and 74,136 otitis media cases could be eliminated from the entire population during a 10-year modelling period. The PCV13 vaccination programme would lead to additional costs (+€26.2 Mio), but saved medical costs of -€77.1 Mio due to cases averted and deaths avoided, overcompensate these costs (total cost savings -€50.9 Mio). The national immunisation programmes with PCV13 can be assumed cost saving when compared with the current vaccine PCV7 in Switzerland. PMID:22521287
Blank, Patricia R; Szucs, Thomas D
Escherichia coli O157 causes severe enteritis and the extraintestinal complication of hemolytic-uremic syndrome, with their highest incidence occurring in children. We postulated that serum immunoglobulin G (IgG) antibodies to the O-specific polysaccharide of lipopolysaccharide (LPS) may confer protective immunity to enteric pathogens by inducing bactericidal reactions against the ingested organisms in the jejunum (J. B. Robbins, C. Chu, and R. Schneerson, Clin. Infect. Dis. 15:346-361, 1992; S. C. Szu, R. Gupta, and J. B. Robbins, p. 381-394, in I. K. Wachsmuth, P. A. Blake, and O. Olsvik, ed., Vibrio cholerae, 1994). Because polysaccharide-protein conjugates induce serum IgG antibodies in infants, we bound the O-specific polysaccharide of E. coli O157 to proteins. E. coli O157 LPS, treated with acetic acid or hydrazine, was derivatized with adipic acid dihydrazide and bound to proteins by carbodiimide-mediated condensation. Conjugates of these adipic hydrazide derivative were prepared with bovine serum albumin, formalin-treated exotoxin C of Clostridium welchii (Pig Bel toxoid), or Pseudomonas aeruginosa recombinant exoprotein A. The conjugates had low levels of endotoxin and elicited serum antibodies with bactericidal activity to the O157 LPS. The largest increase in LPS antibodies was of the IgG class. Clinical evaluation of E. coli O157-toxoid conjugates is planned. Images
Konadu, E; Robbins, J B; Shiloach, J; Bryla, D A; Szu, S C
Escherichia coli O157 causes severe enteritis and the extraintestinal complication of hemolytic-uremic syndrome, with their highest incidence occurring in children. We postulated that serum immunoglobulin G (IgG) antibodies to the O-specific polysaccharide of lipopolysaccharide (LPS) may confer protective immunity to enteric pathogens by inducing bactericidal reactions against the ingested organisms in the jejunum (J. B. Robbins, C. Chu, and R. Schneerson, Clin. Infect. Dis. 15:346-361, 1992; S. C. Szu, R. Gupta, and J. B. Robbins, p. 381-394, in I. K. Wachsmuth, P. A. Blake, and O. Olsvik, ed., Vibrio cholerae, 1994). Because polysaccharide-protein conjugates induce serum IgG antibodies in infants, we bound the O-specific polysaccharide of E. coli O157 to proteins. E. coli O157 LPS, treated with acetic acid or hydrazine, was derivatized with adipic acid dihydrazide and bound to proteins by carbodiimide-mediated condensation. Conjugates of these adipic hydrazide derivative were prepared with bovine serum albumin, formalin-treated exotoxin C of Clostridium welchii (Pig Bel toxoid), or Pseudomonas aeruginosa recombinant exoprotein A. The conjugates had low levels of endotoxin and elicited serum antibodies with bactericidal activity to the O157 LPS. The largest increase in LPS antibodies was of the IgG class. Clinical evaluation of E. coli O157-toxoid conjugates is planned. PMID:7927787
Konadu, E; Robbins, J B; Shiloach, J; Bryla, D A; Szu, S C
Comparison of antibody kinetics following meningococcal serogroup C conjugate vaccine between healthy adults previously vaccinated with meningococcal A/C polysaccharide vaccine and vaccine-naïve controls.
Few data are available on the kinetics of meningococcal serogroup C-specific antibody production following meningococcal serogroup C conjugate (MCC) vaccination, particularly in those who have received prior meningococcal A/C polysaccharide (MACP) vaccination(s). Laboratory staff who had previously received either one dose (n = 35), two doses (n = 18) of MACP vaccine or who were naïve to previous meningococcal vaccination (n = 42) were vaccinated with MCC. Bloods were taken pre-vaccination, on the subsequent 4 days and on days 10 and 28. Serogroup C serum bactericidal antibody (SBA), and anti-serogroup C-specific IgG, IgM and IgA were measured. There were no significant differences between the groups who had received either 2 or 1 prior dose(s) of MACP, therefore, these results were combined. Up to day 4 there was no evidence of a significant increase or decrease in the median levels of SBA, IgG, IgM or IgA in either the naïve or MACP groups, although about 20% of individuals did have 4-fold SBA rises by day 4. By day 10 there were large significant increases in the levels of SBA, IgG, IgM and IgA with respective fold increases from pre-vaccination levels of 4.6, 1.9, 1.2 and 2.1 in the MACP group and 270, 13.4, 4.8 and 33.8 in the naïve group. Further significant increases were seen between day 10 and 28 for SBA, IgG and IgM (naïve group only). By day 28, 4-fold SBA rises had occurred in 63.5% of the MACP group and 97.6% of the naïve group. The SBA GMT on day 28 significantly differed between the naïve and MACP groups with GMTs 2.8-fold higher in the naïve group (P = 0.021). In conclusion, no decline in serogroup C-specific antibody levels was demonstrated immediately post-MCC vaccination whilst these levels had risen significantly by day 10. Putative protective SBA titres (> or =8, 32 or 128) were observed by day 10 following MCC vaccination regardless of MACP history. PMID:11311998
Borrow, R; Southern, J; Andrews, N; Peake, N; Rahim, R; Acuna, M; Martin, S; Miller, E; Kaczmarski, E
...Inactivated Bacterial Products Â§ 113.114 Tetanus Toxoid. Tetanus Toxoid shall be produced from a culture of Clostridium tetani which has been inactivated and is nontoxic. The toxoid may be either absorbed, precipitated, or...
...Inactivated Bacterial Products Â§ 113.114 Tetanus Toxoid. Tetanus Toxoid shall be produced from a culture of Clostridium tetani which has been inactivated and is nontoxic. The toxoid may be either absorbed, precipitated, or...
Background When seven-valent pneumococcal conjugate vaccine was introduced in the USA, many children were vaccinated on schedules that diff ered from those tested in clinical trials. Our aim was to assess the eff ectiveness of the vaccine against various pneumococcal serotypes, and to measure the eff ectiveness of the recommended dose schedule and of catch-up and incomplete schedules. Methods Invasive
Cynthia G Whitney; Monica M Farley; Allen S Craig; Ann-Christine Nyquist; Kenneth A Gershman; Marietta Vazquez; Nancy M Bennett; Arthur Reingold; Mary P Glode; Elizabeth R Zell; James H Jorgensen; Bernard Beall; Anne Schuchat; T Pilishvili MPH; E R Zell MStat
Objective: To explore the effect of a pneumococcal conjugate vaccine on the risk of otitis media with effusion and to search for subgroups in which the vaccine had a higher or lower effect. Methods: Analyses were performed on data from the Finnish Otitis Media Vaccine Trial, a randomised controlled double-blind trial to evaluate the efficacy of pneumococcal conjugate vaccination against
M. Straetemans; A. Palmu; K. Auranen; G. A. Zielhuis; T. Kilpi
Several recently published European cost-effectiveness studies on the 7-valent pneumococcal conjugate vaccine (PCV-7: Prevnar®) have included net-indirect vaccine benefits for non-vaccine protected groups into their studies, which might be too optimistic an approach given recent data. Net-indirect effects result from herd protection minus serotype replacement effects. In this study we analyze the impact of net-indirect effects in non-vaccine protected groups
Mark H. Rozenbaum; Albert Jan van Hoek; Eelko Hak; Maarten J. Postma
Preclinical immunogenicity and functional activity studies of an A+W meningococcal outer membrane vesicle (OMV) vaccine and comparisons with existing meningococcal conjugate- and polysaccharide vaccines.
Meningococci of serogroups A and W (MenA and MenW) are the main causes of epidemic bacterial meningitis outbreaks in sub-Saharan Africa. In this study we prepared a detergent extracted outer membrane vesicle (dOMV) vaccine from representative African MenA and MenW strains, and compared the immunogenicity of this vaccine with existing meningococcal conjugate and polysaccharide (PS) vaccines in mice. NMRI mice were immunized with preclinical batches of the A+W dOMV vaccine, or with commercially available vaccines; a MenA conjugate vaccine (MenAfriVac(®), Serum Institute of India), ACYW conjugate vaccine (Menveo(®), Novartis) or ACYW PS vaccine (Mencevax(®), GlaxoSmithKline). The mice received 2 doses of 1/10 or 1/50 of a human dose with a three week interval. Immune responses were tested in ELISA, serum bactericidal activity (SBA) and opsonophagocytic activity (OPA) assays. High levels of IgG antibodies against both A and W dOMV were detected in mice receiving the A+W dOMV vaccine. High SBA titers against both MenA and MenW vaccine strains were detected after only one dose of the A+W dOMV vaccine, and the titers were further increased after the second dose. The SBA and OPA titers in mice immunized with dOMV vaccine were significantly higher than in mice immunized with the ACYW-conjugate vaccine or the PS vaccine. Furthermore, the A+W dOMV vaccine was shown to induce SBA and OPA titers against MenA of the same magnitude as the titers induced by the A-conjugate vaccine. In conclusion, the A+W dOMV vaccine induced high levels of functional antibodies to both MenA and MenW strains, levels that were shown to be higher or equal to the levels induced by licensed meningococcal vaccines. Thus, an A+W dOMV vaccine could potentially serve as an alternative or a supplement to existing conjugate and PS vaccines in the African meningitis belt. PMID:24120679
Tunheim, G; Arnemo, M; Næss, L M; Fjeldheim, Å K; Nome, L; Bolstad, K; Aase, A; Mandiarote, A; González, H; González, D; García, L; Cardoso, D; Norheim, G; Rosenqvist, E
The complex carbohydrate molecule globo H hexasaccharide has been synthesized, conjugated to keyhole limpet hemocyanin, and administered with the immunologic adjuvant QS-21 as a vaccine for patients with prostate cancer who have relapsed after primary therapies such as radiation or surgery. Globo H is one of several candidate antigens present on prostate cancer cells that can serve as targets for
S. F. Slovin; G. Ragupathi; S. Adluri; G. Ungers; K. Terry; S. Kim; M. Spassova; W. G. Bornmann; M. Fazzari; L. Dantis; K. Olkiewicz; K. O. Lloyd; P. O. Livingston; S. J. Danishefsky; H. I. Scher
background In early 2000, a protein-polysaccharide conjugate vaccine targeting seven pneumococ- cal serotypes was licensed in the United States for use in young children. methods We examined population-based data from the Active Bacterial Core Surveillance of the Centers for Disease Control and Prevention to evaluate changes in the burden of invasive disease, defined by isolation of Streptococcus pneumoniae from a
Cynthia G. Whitney; Monica M. Farley; James Hadler; Lee H. Harrison; Nancy M. Bennett; Ruth Lynfield; Arthur Reingold; Paul R. Cieslak; Tamara Pilishvili; Delois Jackson; Richard R. Facklam; James H. Jorgensen; Anne Schuchat
Background Nowadays, there are two vaccination strategies in Colombia to prevent pneumococcal diseases in people over 50 years. Our aim is to estimate cost-effectiveness of pneumococcal conjugate vaccine 13-valent (PCV13) versus pneumococcal polysaccharide vaccine 23-valent (PPSV23) to prevent pneumococcal diseases and their related mortality in people over 50 years old in Colombia. Methods A Markov model was developed with national data, including pneumococcal serotypes distribution in Colombia between 2005 and 2010. Vaccination of a cohort was simulated and a five year time horizon was assumed. Analysis was done from a perspective of a third party payer. Direct costs were provided by a national insurance company; sensitive univariate and probabilistic analysis were done for epidemiological and clinical effectiveness parameters and costs. Results PCV13 avoids 3 560 deaths by pneumococcal infections versus PPSV23 and 4 255 deaths versus no vaccine. PCV13 prevents 79 633 cases by all-cause pneumonia versus PPSV23 and 81 468 cases versus no vaccine. Total costs (healthcare and vaccines costs) with PCV13 would be U.S. $ 97,587,113 cheaper than PPSV23 and it would save U.S. $ 145,196,578 versus no vaccine. Conclusion PCV13 would be a cost-saving strategy in the context of a mass vaccination program in Colombia to people over 50 years old because it would reduce burden of disease and specific mortality by pneumococcal diseases, besides, it saves money versus PPSV23.
Infant vaccination with meningococcal conjugates may provide long-term protection against disease. Antibody levels and immunologic memory were assessed in 5-year-old Gambian children who received meningococcal A/C conjugate vaccination (MenA/C) in infancy. At 2 years, they were randomized to receive a booster of MenA/C (conjugate group), meningococcal A/C polysaccharide (MPS group), or inactivated polio vaccine (IPV group). All groups were revaccinated with 10 microg MPS at 5 years of age, as were 39 previously unvaccinated age-matched control subjects. Before revaccination, titers were higher in the conjugate and MPS groups than in control subjects (P<.001); titers for the IPV group were similar to those for control subjects. Ten days after revaccination, the conjugate and IPV groups had similar serogroup C serum bactericidal antibody titers (3421 vs. 2790, respectively). These levels were significantly higher than those in the MPS (426) and control (485) groups (P<.001). Thus, immunologic memory was sustained for > or =5 years; however, MPS challenge at 2 years interfered with a subsequent memory response. PMID:11087205
MacLennan, J; Obaro, S; Deeks, J; Lake, D; Elie, C; Carlone, G; Moxon, E R; Greenwood, B
To overcome the limitations of the current pertussis vaccines, those of limited duration of action and failure to induce direct killing of Bordetella pertussis, a synthetic scheme was devised for preparing a conjugate vaccine composed of the Bordetella bronchiseptica core oligosaccharide with one terminal trisaccharide to aminooxylated BSA via their terminal ketodeoxyoctanate residues. Conjugate-induced antibodies, by a fraction of an estimated human dose injected into young outbred mice as a saline solution, were bactericidal against B. pertussis, and their titers correlated with their ELISA values. The carrier protein is planned to be genetically altered pertussis toxoid. Such conjugates are easy to prepare, stable, and should add both to the level and duration of immunity induced by current vaccine-induced pertussis antibodies and reduce the circulation of B. pertussis. PMID:24556987
Robbins, John B; Schneerson, Rachel; Kubler-Kielb, Joanna; Keith, Jerry M; Trollfors, Birger; Vinogradov, Evgeny; Shiloach, Joseph
Activation of soluble polysaccharides with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) for use in protein-polysaccharide conjugate vaccines and immunological reagents. II. Selective crosslinking of proteins to CDAP-activated polysaccharides.
Covalently linking protein to polysaccharides converts the anti-polysaccharide immune response from a T-cell independent response to one which is T-cell dependent. The organic cyanylating reagent 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) (Vaccine 14:190, 1996) has been used to activate polysaccharides, which can then be reacted with spacer reagents or directly with protein. We wished to explore ways in which proteins could be linked to CDAP-activated polysaccharides to conjugate in a more controlled and selective fashion. To this end, we examined the reaction of nucleophilic amino acids with CDAP-activated polysaccharides under basic and acidic conditions. We found that lysine, cysteine and histidine but not methionine, serine or tyrosine conjugated to CDAP-activated dextran. We also examined the reaction of various spacer reagents with CDAP-activated dextran as a function of pH. The addition of hexanediamine was highly pH dependent and maximal at pH 9.3. In contrast, the addition of adipic dihydrazide, which has a pKa of ca 2.5 was essentially independent of pH. By performing the conjugation reaction at pH 5, we were able to selectively couple hydrazides even in the presence of high concentrations of amines. Proteins derivatized with limited numbers of hydrazides could be conjugated to CDAP-activated polysaccharides at pH5, where the native protein was not reactive. Proteins could be derivatized with hydrazides on carboxyls using adipic dihydrazide and a water soluble carbodiimide or on amines using a mild two-step reaction. Tetanus toxoid-pneumococcal type 14 conjugates produced by coupling hydrazide-derivatized tetanus toxoid under acidic conditions induced anti-polysaccharide antibodies at titers comparable to that stimulated by conjugates produced using a basic coupling pH. Our data suggest that crosslinking was occurring only with the limited number of hydrazides on the protein and that we achieved limited and selective crosslinking between the protein and CDAP-activated polysaccharide. This work also demonstrates that CDAP-mediated conjugation to polysaccharides can be applied even to very pH sensitive proteins and polysaccharides. PMID:10649629
Shafer, D E; Toll, B; Schuman, R F; Nelson, B L; Mond, J J; Lees, A
The development of acellular pertussis vaccines has raised a number of issues relevant to the control of these products. Of particular importance is the need for robust and accuratein vitroassays for the antigen content of the vaccines which might contain up to five different antigen components, each of which needs to be independently assayed. This paper describes a simple method
Dorothy K. L. Xing; Catpagavalli Canthaboo; Michael J. Corbel; Geoffrey C. Schild
We investigated the incidence and distribution of cases of invasive pneumococcal disease (IPD), invasive meningococcal disease (IMD) and invasive Hemophilus influenzae disease (IHiD) notified by hospital laboratories to the Microbiological Reporting System of Catalonia between 2005 and 2009. Incidence rates were compared using the rate ratio (RR) and 95% CI were calculated. A value of p < 0.05 was considered statistically significant. Of the 6,661 cases, 6,012 were IPD, 436 IMD and 213 IHiD. The global annual incidence per 105 inhabitants was 16.62 (95% CI 16.20–17.04) for IPD, 1.21 (95% CI 1.09–1.32) for IMD and 0.59 (95% CI 0.51–0.67) for IHiD. IPD increased in 2009 compared with 2005 (RR:1.55, 95%CI: 1.43–1.70) and IMD and IHiD remained stable. Pneumonia was the most-frequent clinical manifestation of IPD (75.6%) and IHiD (44.1%) and meningoencephalitis with or without sepsis for IMD (70.6%). The male:female ratio was 1.37 for IPD, 1.0 for IMD and 1.15 for IHiD. The age groups with the highest incidence were the ? 2 y and 2–4 y groups for IPD (66.40 and 50.66/100,000 persons-year) and IMD (14.88 and 7.26/100,000 persons-year) and the ? 2 y and ? 65 y groups for IHiD (1.88 and 1.89/100,000 persons-year). The most-frequent serotypes were serotype 1 (19.0%) in IPD and untypeable serotypes (60.8%) in IHiD. Serogroup B (78.3%) was the most frequent in IMD. S. pneumoniae is the most-frequent agent causing invasive disease in Catalonia. The main clinical manifestations were pneumonia in IPD and IHiD and meningitis in IMD. The main causative agent of meningitis was N. meningitidis in people aged < 20 y and S. pneumoniae in people aged ? 20 y. Vaccination with conjugate vaccines may reduce the risk of infectious disease in our setting.
Ciruela, Pilar; Martinez, Ana; Izquierdo, Conchita; Hernandez, Sergi; Broner, Sonia; Munoz-Almagro, Carmen; Dominguez, Angela; of Catalonia Study Group, the Microbiological Reporting System
A universal influenza virus vaccine that does not require frequent updates and\\/or annual immunizations will offer significant advantages over current seasonal flu vaccines. The highly conserved influenza virus A M2 membrane protein has been previously suggested as a potential antigen target for such a vaccine. Here, we report systematic evaluation of M2 peptide conjugate vaccines (synthetic peptides of M2 extracellular
Jiang Fan; Xiaoping Liang; Melanie S Horton; Helen C Perry; Michael P Citron; Gwen J Heidecker; Tong-Ming Fu; Joseph Joyce; Craig T Przysiecki; Paul M Keller; Victor M Garsky; Roxana Ionescu; Yvette Rippeon; Li Shi; Michael A Chastain; Jon H Condra; Mary-Ellen Davies; Jason Liao; Emilio A Emini; John W Shiver
Antigen-specific humoral response, as well as the induction of cellular immunity generated by Candida dubliniensis mannan-human serum albumin (HSA) conjugate, a novel proposed immunogenic structure for subcellular vaccine, were evaluated in rabbits. Mannan-HSA conjugate-induced specific IgG and IgA increased significantly after boosters (IgG: P<0.001 and IgA: P<0.01). Mannan-HSA conjugate up-regulation of cell-surface expression of B-lymphocyte and granulocyte activation antigens CD25 and CD11b indicated the effective activation. Immunogenic effect of conjugate on T lymphocytes was demonstrated via inductive increase of CD4+ T lymphocyte subset and CD4+/CD8+ ratio and via induction of T(H)1 cytokines. Immunogenic effectiveness of mannan-HSA conjugate at a dose of 0.25 mg of mannan antigenic moiety overcame that of the mannan alone and of yeast whole cells, thus promising further application in Candida vaccine development. PMID:17673147
Paulovicová, Ema; Machová, Eva; Tulinská, Jana; Bystrický, Slavomír
Polysaccharide-protein conjugates as vaccines have proven to be very effective in preventing Haemophilus influenzae type b infections in industrialized countries. However, cost-effective technologies need to be developed for increasing the availability of anti-H. influenzae type b vaccines in countries from the developing world. Consequently, vaccine production with partially synthetic antigens is a desirable goal for many reasons. They may be rigidly controlled for purity and effectiveness while at the same time being cheap enough that they may be made universally available. We describe here the antigenicity and immunogenicity of several H. influenzae type b synthetic oligosaccharide-protein conjugates in laboratory animals. The serum of H. influenzae type b-immunized animals recognized our synthetic H. influenzae type b antigens to the same extent as the native bacterial capsular polysaccharide. Compared to the anti-H. influenzae type b vaccine employed, these synthetic versions induced similar antibody response patterns in terms of titer, specificity, and functional capacity. The further development of synthetic vaccines will meet urgent needs in the less prosperous parts of the world and remains our major goal. PMID:15557635
Fernández-Santana, V; Cardoso, Félix; Rodriguez, Arlene; Carmenate, Tania; Peña, Luis; Valdés, Yuri; Hardy, Eugenio; Mawas, Fatme; Heynngnezz, Lazaro; Rodríguez, Maria C; Figueroa, Ignacio; Chang, Janoi; Toledo, Maria E; Musacchio, Alexis; Hernández, Ibis; Izquierdo, Mabel; Cosme, Karelia; Roy, Rene; Verez-Bencomo, V
The active components of most meningococcal vaccines are four antigenic serogroup capsular polysaccharides (A, C, Y, W135). The vaccines, monovalent or multivalent mixtures of either free polysaccharides or polysaccharides conjugated to antigenic carrier proteins, may be in liquid or lyophilised formulations, with or without excipients. Acid hydrolysis and chromatographic methods for serogroup quantitation, which were previously optimised and qualified using polysaccharide-based standards and a narrow range of real vaccines, are here challenged with multiple lots of a broad assortment of additional multivalent polysaccharide-based meningococcal vaccine products. Centrifugal filtration successfully removed all interfering lactose excipient without loss of polysaccharides to allow for the determination of Y and W135 serogroups. Replicate operations by three different analysts indicated high method reproducibility. Results indicated some lot-to-lot and product-to-product variations. However, all vaccines were within general specifications for each serogroup polysaccharide, with the exception of all lots of one polysaccharide vaccine - which by these methods were found to be deficient in the serogroup A component only. These robust techniques are very useful for the evaluation of antigen content and consistency of manufacture. The deformulation, hydrolysis and chromatographic methods may be adaptable for the evaluation of other types of polysaccharide-based vaccines. PMID:23665303
Cook, Matthew C; Gibeault, Sabrina; Filippenko, Vasilisa; Ye, Qiang; Wang, Junzhi; Kunkel, Jeremy P
We tested intranasal application of anti-Pseudomonas conjugate vaccine in mice. Comparison of immunisation via the intra-muscular versus intranasal routes showed the induction of equivalent levels of specific serum IgG and IgG subclasses antibodies if cholera toxin was used as an adjuvant. In contrast, secretion of specific mucosal IgA antibodies in the upper respiratory tract was only observed after intranasal immunisation
Adrian W. Zuercher; Michael P. Horn; Hong Wu; Zhijun Song; Cathrine J. Bundgaard; Helle Krogh Johansen; Niels Høiby; Paul Marcus; Alois B. Lang
Background Several decision support tools have been developed to aid policymaking regarding the adoption of pneumococcal conjugate vaccine\\u000a (PCV) into national pediatric immunization programs. The lack of critical appraisal of these tools makes it difficult for\\u000a decision makers to understand and choose between them. With the aim to guide policymakers on their optimal use, we compared\\u000a publicly available decision-making tools in
Nathorn Chaiyakunapruk; Ratchadaporn Somkrua; Raymond Hutubessy; Ana Maria Henao; Joachim Hombach; Alessia Melegaro; John W Edmunds; Philippe Beutels
Background.?The Gambia was the first country in Africa to introduce conjugate Haemophilus influenzae type b (Hib) vaccine, which, as in other developing countries but unlike industrialized countries, is delivered as a 3-dose primary series with no booster. This study assessed its effectiveness 14 years after introduction. Methods.?Using methods standardized during >20 years in the study site, clinical and microbiological surveillance for invasive Hib disease (primarily meningitis) in the Western Region of The Gambia from 2007 to 2010 was complemented with studies of Hib carriage in children aged 1 to <2 years, Hib antibody levels in children aged <5 years, and Hib vaccine coverage and timing in children aged 1 to <2 years. Results.?The incidence of Hib meningitis remained low (averaging 1.3 per 100 000 children aged <5 years annually), as did the Hib oropharyngeal carriage rate (0.9%). Hib antibody levels were protective in >99% of those surveyed, albeit with lower titers in older children; and coverage of conjugate Hib vaccination was high (91% having 3 doses at 1–2 years of age) using a schedule that was delivered at median ages of 2.6 months, 4.3 months, and 6 months for the first, second, and third doses, respectively. Conclusions.?Conjugate Hib vaccine was delivered on time in a 3-dose primary series without booster to a high proportion of eligible children and this was associated with effective disease control up to 14 years after introduction. It is important that surveillance continues in this first African country to introduce the vaccine to determine if effective control persists or if a booster dose becomes necessary as has been the case in industrialized countries.
Howie, Stephen R. C.; Oluwalana, Claire; Secka, Ousman; Scott, Susana; Ideh, Readon C.; Ebruke, Bernard E.; Balloch, Anne; Sambou, Sana; Erskine, James; Lowe, Yamundow; Corrah, Tumani; Adegbola, Richard A.
In this study, the adjuvant effect of the sustained release biodegradable nanospheres (100-150 nm in diameter) has been compared with alum. Nanospheres were formulated using a biodegradable polylactic polyglycolic acid copolymer (PLGA, 50:50) containing Staphylococcal Enterotoxin B (SEB) toxoid as a model vaccine antigen. Systemic immune response of the nanospheres containing toxoid was studied in rabbits by subcutaneous immunization. The data demonstrated that approximately 30% of the toxoid activity was lost following its encapsulation into nanospheres. Under in vitro conditions, nanospheres demonstrated sustained release of the toxoid. However, only 20% of the antigenic toxoid was released over the first 2 weeks of the release study. Immunization of animals with equal doses of toxoid, either using nanospheres or alum induced a comparable systemic immune response (IgG, IgM and IgA). The immune response reached a maximum level at 7 weeks post-immunization, which then gradually declined with time. The booster dose of toxoid at 19 weeks, either using alum or nanospheres induced similar immune response in both the groups, but was greater than the primary immune response. The studies, thus, suggest that biodegradable nanospheres could be used as a vaccine adjuvant. PMID:10738697
Desai, M P; Hilfinger, J M; Amidon, G L; Levy, R J; Labhasetwar, V
Background The meningococcal serogroup A (MenA) polysaccharide conjugate vaccine used in Sub-Saharan Africa does not prevent disease caused by MenW or MenX strains, which also cause epidemics in the region. We investigated the vaccine-potential of native outer membrane vesicles with over-expressed factor H-binding protein (NOMV-fHbp), which targeted antigens in African meningococcal strains, and was combined with a MenA polysaccharide conjugate vaccine. Methodology/Principal Findings The NOMV-fHbp vaccine was prepared from a mutant African MenW strain with PorA P1.5,2, attenuated endotoxin (?LpxL1), deleted capsular genes, and over-expressed fHbp in variant group 1. The NOMV-fHbp was adsorbed with Al(OH)3 and used to reconstitute a lyophilized MenA conjugate vaccine, which normally is reconstituted with liquid MenC, Y and W conjugates in a meningococcal quadrivalent conjugate vaccine (MCV4-CRM, Novartis). Mice immunized with the NOMV-fHbp vaccine alone developed serum bactericidal (human complement) activity against 13 of 15 African MenA strains tested; 10 of 10 African MenX strains, 7 of 7 African MenW strains, and 6 of 6 genetically diverse MenB strains with fHbp variant group 1 (including 1 strain from The Gambia). The combination NOMV-fHbp/MenA conjugate vaccine elicited high serum bactericidal titers against the two MenA strains tested that were resistant to bactericidal antibodies elicited by the NOMV-fHbp alone; the combination elicited higher titers against the MenA and MenW strains than those elicited by a control MCV4-CRM vaccine (P<0.05); and high titers against MenX and MenB strains. For most strains, the titers elicited by a control NOMV-fHbp knock out vaccine were <1?10 except when the strain PorA matched the vaccine (titers >1?000). Conclusion/Significance The NOMV-fHbp/MenA conjugate vaccine provided similar or higher coverage against MenA and MenW strains than a quadrivalent meningococcal conjugate vaccine, and extended protection against MenX strains responsible for epidemics in Africa, and MenB strains with fHbp in variant group 1.
Pajon, Rolando; Fergus, Andrew M.; Granoff, Dan M.
Acute otitis media (AOM) is a leading cause of visits to physicians and of antibiotic prescriptions for young children. We systematically reviewed studies on all-cause AOM episodes and physician visits in which impact was attributed to pneumococcal conjugate vaccines, either as efficacy or effectiveness. Of 18 relevant publications found, most used the 7-valent pneumococcal conjugate vaccine (7vCRM). The efficacy of 7vCRM against all-cause AOM episodes or visits was 0%–9% in randomized trials and 17%–23% in nonrandomized trials. In observational database studies, physician visits for AOM were already declining in the 3–5 years before 7vCRM introduction (mean change, ?15%; range, +14% to ?24%) and continued to decline afterward (mean, ?19%; range, +7% to ?48%). This vaccine provides some protection against OM, but other factors have also contributed to the recent decline in OM incidence. Future effectiveness studies should thus use better-controlled methods to estimate the true impact of vaccination on AOM.
Taylor, Sylvia; Marchisio, Paola; Vergison, Anne; Harriague, Julie; Hausdorff, William P.; Haggard, Mark
As part of an ongoing study of the response of the Streptococcus pneumoniae population to conjugate vaccination, we applied multi-locus sequence typing (MLST) to 291 isolates sampled from nasopharyngeal carriage in Massachusetts children. We found 94 distinct sequence types (STs), including 19 that had not been previously recorded, and a xpt allele containing a large insertion. Comparison with a similar sample collected in 2007 revealed no significant overall difference in the ST composition (p=0.51) suggesting that the population has reached a new equilibrium following the introduction of 7 valent vaccination in 2000. Within serotypes, a large and statistically significant increase (p=0.014 Fisher’s Exact test) was noted in the prevalence of the major multiresistant clone ST 320, which is apparently outcompeting ST 199 among serotype 19A strains. This sample will be used as a baseline to study the future evolution of the pneumococcal population in Massachusetts following introduction of vaccines with higher valency.
Bishop, C. J.; Lee, G. M.; Lipsitch, M.; Stevenson, A; Rifas-Shiman, S. L.; Pelton, S. I.; Huang, S. S.; Finkelstein, J. A.
Mice were orally vaccinated with liposomes coated with filamentous hemagglutinin (FHA) and detoxified pertussis toxin (PT) of Bordetella pertussis. FHA- and PT-specific immunoglobulin G (IgG) was detected in serum, and both IgG and IgA were detected in lung washes following the immunization. Antibody responses in mice immunized with liposomes coated with FHA and PT were significantly higher than those in mice immunized with free FHA and PT, which demonstrated the adjuvanticity of the liposome carrier. The results indicate the potential usefulness of this approach for eliciting immune responses against FHA and PT (and perhaps other pertussis antigens) in humans and its possible utility in large-scale vaccination to protect against both B. pertussis infection and disease. Images
Guzman, C A; Molinari, G; Fountain, M W; Rohde, M; Timmis, K N; Walker, M J
Hib conjugate vaccines are widely used in the industrialized world, but are just now beginning to be introduced into other countries. To identify factors facilitating rapid global introduction, we evaluated the decision-making process, mode of introduction, effectiveness, and impact on the immunization program of Hib conjugate vaccine introduction in four non- industrialized countries through site visits and use of a standardized questionnaire. The key promoters of Hib introduction were the pediatric community and ministries of health. Local surveillance and severity data were critical in the decision to adopt Hib vaccine. Assistance with surveillance, introduction guidelines, educational material, tenders, and funding is needed to accelerate wider adoption. PMID:10547434
Wenger, J D; DiFabio, J; Landaverde, J M; Levine, O S; Gaafar, T
A 12 ammo-acid synthetic peptide (NANP)3 comprising the immunodominant epitope of Plasmodium falciparum circum-sporozoite protein was conjugated to tetanus toxoid (TT), adjuvan-ted with aluminium hydroxide, and administered intramuscularly in three doses at monthly intervals to 35 healthy males as a malaria vaccine. No significant adverse reactions were noted, with mild soreness at the injection site the only common symptom. Serocon-versions
Deirdre A. Herrington; David F. Clyde; Genevieve Losonsky; Manuel Cortesia; James R. Murphy; Jonathan Davis; Shahida Baqar; Arthur M. Felix; Edgar P. Heimer; Dieter Gillessen; Elizabeth Nardin; Ruth S. Nussenzweig; Victor Nussenzweig; Michael R. Hollingdale; Myron M. Levine
Successful efforts to control infectious diseases have often required the use of effective vaccines. The current global strategy for control of malaria, including elimination and eradication will also benefit from the development of an effective vaccine that interrupts malaria transmission. To this end, a vaccine that disrupts malaria transmission within the mosquito host has been investigated for several decades targeting a 25 kDa ookinete specific surface protein, identified as Pfs25. Phase 1 human trial results using a recombinant Pfs25H/Montanide ISA51 formulation demonstrated that human Pfs25 specific antibodies block parasite infectivity to mosquitoes; however, the extent of blocking was likely insufficient for an effective transmission blocking vaccine. To overcome the poor immunogenicity, processes to produce and characterize recombinant Pfs25H conjugated to a detoxified form of Pseudomonas aeruginosa exoprotein A (EPA) have been developed and used to manufacture a cGMP pilot lot for use in human clinical trials. The Pfs25-EPA conjugate appears as a nanoparticle with an average molar mass in solution of approximately 600 kDa by static light scattering with an average diameter 20 nm (range 10 to 40 nm) by dynamic light scattering. The molar ratio of Pfs25H to EPA is about 3 to 1 by amino acid analysis, respectively. Outbred mice immunized with the Pfs25-EPA conjugated nanoparticle formulated on Alhydrogel® had a 75 to 110 fold increase in Pfs25H specific antibodies when compared to an unconjugated Pfs25H/Alhydrogel® formulation. A phase 1 human trial using the Pfs25-EPA/Alhydrogel® formulation is ongoing in the United States.
Shimp, Richard L.; Rowe, Christopher; Reiter, Karine; Chen, Beth; Nguyen, Vu; Aebig, Joan; Rausch, Kelly M.; Kumar, Krishan; Wu, Yimin; Jin, Albert J.; Jones, David S.; Narum, David L.
The implementation of the seven-valent pneumococcal conjugate vaccine, PCV7, has resulted in significant changes in the pneumococcal population being carried and causing disease. We aimed to determine the invasive disease potential of serotypes causing invasive paediatric disease in the era of conjugate vaccines in Catalonia, Spain, and their potential coverage by the 13-valent pneumococcal conjugate vaccine, PCV13. As a secondary objective, we evaluated whether implementation of PCV7 had resulted in significant changes in the invasive disease potential of the most frequent serotypes circulating in the area. Two pneumococcal collections obtained from children admitted to the University Hospital Sant Joan de Déu (Barcelona, Spain) between 2007 and 2011 were compared: a first set of 159 invasive disease isolates, and a second set of 209 nasopharyngeal isolates recovered from healthy children admitted for minor surgery. The most common invasive serotypes were 1 (24.5%, n = 39), 19A (21.2%, n = 34), 5 (8.8%, n = 14), 7F (8.8%, n = 14) and 3 (5%, n = 8). The most common serotypes in carriage were 19A (10%, n = 21), 6C (9%, n = 19), 23B (8.1%, n = 17), 6A (7.6%, n = 16) and 19F (6.2%, n = 13). A significantly higher propensity to cause invasive disease was observed for serotypes 1, 3, 5, 7F and 19A, all of which are included in PCV13. After false-discovery-rate correction, the results were robust for serotypes 1, 5, 7F and 19A. Non-PCV13 serotypes had a low invasive disease potential. Our data reinforce the need for continuous surveillance and should encourage efforts to introduce universal vaccination with PCV13 in children in our region. PMID:24467648
Del Amo, E; Brotons, P; Monsonis, M; Triviño, M; Iñigo, M; Selva, L; Sa-Leão, R; Muñoz-Almagro, C
Successful efforts to control infectious diseases have often required the use of effective vaccines. The current global strategy for control of malaria, including elimination and eradication will also benefit from the development of an effective vaccine that interrupts malaria transmission. To this end, a vaccine that disrupts malaria transmission within the mosquito host has been investigated for several decades targeting a 25 kDa ookinete specific surface protein, identified as Pfs25. Phase 1 human trial results using a recombinant Pfs25H/Montanide ISA51 formulation demonstrated that human Pfs25 specific antibodies block parasite infectivity to mosquitoes; however, the extent of blocking was likely insufficient for an effective transmission blocking vaccine. To overcome the poor immunogenicity, processes to produce and characterize recombinant Pfs25H conjugated to a detoxified form of Pseudomonas aeruginosa exoprotein A (EPA) have been developed and used to manufacture a cGMP pilot lot for use in human clinical trials. The Pfs25-EPA conjugate appears as a nanoparticle with an average molar mass in solution of approximately 600 kDa by static light scattering with an average diameter 20 nm (range 10-40 nm) by dynamic light scattering. The molar ratio of Pfs25H to EPA is about 3 to 1 by amino acid analysis, respectively. Outbred mice immunized with the Pfs25-EPA conjugated nanoparticle formulated on Alhydrogel(®) had a 75-110 fold increase in Pfs25H specific antibodies when compared to an unconjugated Pfs25H/Alhydrogel(®) formulation. A phase 1 human trial using the Pfs25-EPA/Alhydrogel(®) formulation is ongoing in the United States. PMID:23623858
Shimp, Richard L; Rowe, Christopher; Reiter, Karine; Chen, Beth; Nguyen, Vu; Aebig, Joan; Rausch, Kelly M; Kumar, Krishan; Wu, Yimin; Jin, Albert J; Jones, David S; Narum, David L
The incidence of antigenuria was documented after vaccination of 75 children 15 to 60 months of age with one of three Haemophilus influenzae type b conjugate vaccines, PRP-D (ProHIBiT), PRP-T and HbOC (HibTITER). Unconcentrated and concentrated urine was tested on the first, third, fifth and seventh days after vaccination. Antigenuria occurred on Day 1 in 100% of PRP-D, 43% of PRP-T and 12% of HbOC recipients. The percentages of children excreting antigen on Day 3 were 95, 17 and 8%; on Day 5 they were 36, 4 and 12%; and on Day 7 they were 14, 0 and 18% for PRP-D, PRP-T and HbOC, respectively. The difference in the occurrence of antigenuria resulting from each vaccine was statistically significant on Day 1 and for PRP-D compared with PRP-T or HbOC on Day 3. It is important for clinicians to be aware of the frequency with which antigenuria occurs after these vaccines so that appropriate therapeutic decisions can be made. PMID:2062627
Rothstein, E P; Madore, D V; Girone, J A; Schiller, R P; Hipp, T J; Souder, R L; Bernstein, H H
Background 10-valent conjugate pneumococcal vaccine/PCV10 was introduced in the Brazilian National Immunization Program along the year of 2010. We assessed the direct effectiveness of PCV10 vaccination in preventing nasopharyngeal/NP pneumococcal carriage in infants. Methods A cross-sectional population-based household survey was conducted in Goiania Brazil, from December/2010-February/2011 targeting children aged 7–11 m and 15–18 m. Participants were selected using a systematic sampling. NP swabs, demographic data, and vaccination status were collected from 1,287 children during home visits. Main outcome and exposure of interest were PCV10 vaccine-type carriage and dosing schedules (3p+0, 2p+0, and one catch-up dose), respectively. Pneumococcal carriage was defined by a positive culture and serotyping was performed by Quellung reaction. Rate ratio/RR was calculated as the ratio between the prevalence of vaccine-types carriage in children exposed to different schedules and unvaccinated for PCV10. Adjusted RR was estimated using Poisson regression. PCV10 effectiveness/VE on vaccine-type carriage was calculated as 1-RR*100. Results The prevalence of pneumococcal carriage was 41.0% (95%CI: 38.4–43.7). Serotypes covered by PCV10 and PCV13 were 35.2% and 53.0%, respectively. Vaccine serotypes 6B (11.6%), 23F (7.8%), 14 (6.8%), and 19F (6.6%) were the most frequently observed. After adjusted for confounders, children who had received 2p+0 or 3p+0 dosing schedule presented a significant reduction in pneumococcal vaccine-type carriage, with PCV10 VE equal to 35.9% (95%CI: 4.2–57.1; p?=?0.030) and 44.0% (95%CI: 14.–63.5; p?=?0.008), respectively, when compared with unvaccinated children. For children who received one catch-up dose, no significant VE was detected (p?=?0.905). Conclusion PCV10 was associated with high protection against vaccine-type carriage with 2p+0 and 3p+0 doses for children vaccinated before the second semester of life. The continuous evaluation of carriage serotypes distribution is likely to be useful for evaluating the long-term effectiveness and impact of pneumococcal vaccination on serotypes reduction.
Andrade, Ana Lucia; Ternes, Yves Mauro; Vieira, Maria Aparecida; Moreira, Weslley Garcia; Lamaro-Cardoso, Juliana; Kipnis, Andre; Cardoso, Maria Regina; Brandileone, Maria Cristina; Moura, Iaci; Pimenta, Fabiana C.; da Gloria Carvalho, Maria; Saraiva, Fabricia Oliveira; Toscano, Cristiana Maria; Minamisava, Ruth
Morphine conjugate vaccines have effectively reduced behavioral effects of heroin in rodents and primates. To better understand how these effects are mediated, heroin and metabolite distribution studies were performed in rats in the presence and absence of vaccination. In non-vaccinated rats 6-monoacetylmorphine (6-MAM) was the predominant opioid in plasma and brain as early as 1 minute after i.v. administration of heroin and for up to 14 minutes. Vaccination with morphine conjugated to keyhole limpet hemocyanin (M-KLH) elicited high titers and concentrations of antibodies with high affinity for heroin, 6-MAM, and morphine. Four minutes after heroin administration vaccinated rats showed substantial retention of all three opioids in plasma compared to controls and reduced 6-MAM and morphine, but not heroin, distribution to brain. Administration of 6-MAM rather than heroin in M-KLH vaccinated rats showed a similar drug distribution pattern. Vaccination reduced heroin-induced analgesia and blocked heroin-induced locomotor activity throughout 2 weeks of repeated testing. Higher serum opioid-specific antibody concentrations were associated with higher plasma opioid concentrations, lower brain 6-MAM and morphine concentrations, and lower heroin-induced locomotor activity. Serum antibody concentrations over 0.2 mg/ml were associated with substantial effects on these measures. These data support a critical role for 6-MAM in mediating the early effects of i.v. heroin and suggest that reducing 6-MAM concentration in brain is essential to the efficacy of morphine conjugate vaccines.
Pravetoni, M.; Harris, A.C.; Birnbaum, A.K.; Pentel, P.R.
Antibody responses to the infecting serotype in children who are vaccinated with pneumococcal conjugate vaccine (PCV) after having invasive pneumococcal diseases (IPD) have not been fully investigated. Of 56 children diagnosed with IPD between October 2009 and April 2013 in whom the infecting serotype was confirmed, 17 who were vaccinated with PCV7 following IPD were tested to determine the geometric mean concentration of serotype-specific immunoglobulin G (IgG) and the geometric mean titers of opsonization indices (OIs) using paired sera obtained at the onset of IPD and after PCV doses following the resolution of IPD. The geometric mean concentrations of serotype-specific IgG for all PCV7 serotypes other than serotype 6B were significantly increased after the last PCV7 dose compared with those at the time of IPD onset (P<0.01), as were the geometric mean titers of OIs for all PCV7 serotypes. In 14 children with IPD caused by PCV7 serotypes for whom both IgG and OI results were available, the OIs for the infecting serotype at the time of IPD onset were <8, although the IgG levels varied between from <0.2 to >5.0?g/ml. After the last PCV7 dose, the OIs for the infecting serotype remained <8 for six (43%) of 14 children. In these six children, hyporesponsiveness to PCV7 was specific for the infecting serotype. Hyporesponsiveness was found for serotypes 6B (n=5) and 23F (n=1). No difference was found between the responders (n=8) and the hyporesponders (n=6) with regard to any clinical characteristics. Our data suggest that hyporesponsiveness to the infecting serotype may occur in children vaccinated with PCV7 following IPD. PMID:24486367
Tamura, Kazuyo; Matsubara, Kousaku; Ishiwada, Naruhiko; Nishi, Junichiro; Ohnishi, Hidenori; Suga, Shigeru; Ihara, Toshiaki; Chang, Bin; Akeda, Yukihiro; Oishi, Kazunori
Children who had been randomized to receive one dose of either heptavalent pneumococcal polysaccharide–meningococcal outer membrane protein complex conjugate vaccine (PCV) or 23-valent pneumococcal polysaccharide vaccine (PN23) at 12, 15, or 18 months of age were subsequently randomized to receive a booster injection of either PCV or PN23 12 months later. For those children who received a priming dose of
Michael D. Blum; Ron Dagan; Paul M. Mendelman; Vered Pinsk; Michael Giordani; Shu Li; Norman Bohidar; Tessie B. McNeely
Conjugation of carbohydrate antigens to protein carriers significantly improves the immune response to many carbohydrates. In order to evaluate the potential for this approach to improve the performance of pneumococcal vaccine in the elderly, we evaluated pneumococcal polysaccharide-derived oligosaccharides conjugated to cross-reacting material 197 (CRM197) (CRM-OS) in 49 older adults over 60 years of age (median age, 66 years) and compared the results to those from 50 younger adults under age 45 (median age, 27 years). Subjects were randomly assigned to receive licensed 23-valent polysaccharide vaccine (PS) which contain 25 micrograms of polysaccharide per serotype, or 5-valent CRM-OS, which contains 10 micrograms of oligosaccharide per serotype, in double-blind fashion. Both vaccines were associated with moderate local pain on administration. Antibody responses to type 14 were seen in the majority of both younger and older subjects following administration of both CRM-OS and PS, and there was no significant improvement of responses with CRM-OS in either age group. Antibody responses in young adults to the less immunogenic type 6B were seen in only 36% of subjects receiving PS and in 56% of subjects receiving CRM-OS (P = 0.15), and the geometric mean 6B titer 1 month after vaccination was higher in CRM-OS recipients (10.9 versus 3.7 micrograms/ml; P = 0.04). However, 6B responses were poor following the administration of either vaccine to elderly adults and there was no difference between results with CRM-OS and those with PS in this age group. Relatively few subjects developed measurable mucosal immunoglobulin A responses in nasal secretions following administration of either vaccine. Revaccination of CRM-OS recipients with PS at 2 months did not result in significant additional responses to 6B or 14. Though CRM-OS is possibly more immunogenic in young adults, the formulation of the pneumococcal glycoconjugate vaccine used in this study does not appear to offer an advantage to the elderly for types 6B or 14.
Shelly, M A; Jacoby, H; Riley, G J; Graves, B T; Pichichero, M; Treanor, J J
In spite of the clear importance of protein O-mannosylation in brain glycobiology, tools are lacking for specific detection, enrichment, and identification of proteins containing these modifycations. We envisioned inducing antibodies that specifically recognize O-mannose glycans on proteins and peptides. With this in mind, we prepared a glycopeptide vaccine construct containing the N-acetyllactosamine-extended mannose motif Gal?1-4GlcNAc?1-2Man?Thr, found as a common core structure on almost all mammalian O-mannosyl glycoproteins identified. O-mannose glycosylated amino acid building blocks and the corresponding glycopeptides were prepared by chemical synthesis and then conjugated to an immune carrier protein. After administration of the synthetic vaccine into rabbits, strong immune responses were obtained. Further evaluation by ELISA neutralization experiments and glycopeptide microarrays showed that the induced antibodies were highly specific to the glycopeptide antigen. PMID:24753400
Yu, Jin; Westerlind, Ulrika
During June-August 2005, CDC and the Food and Drug Administration (FDA) were notified of seven clusters of inadvertent subcutaneous (SC) misadministration of the new meningococcal conjugate vaccine (MCV4, Menactra) (Sanofi Pasteur, Inc., Swiftwater, Pennsylvania), which is licensed for intramuscular (IM) administration only. A total of 101 persons in seven states were reported to have received MCV4 by the SC route. Of these, 100 were contacted by their health-care providers and advised of the administration error. CDC conducted an investigation to determine whether SC administration of MCV4 resulted in a protective immunologic response. This report describes the results of that investigation, which indicated that, despite the misadministration, persons vaccinated by the SC route were sufficiently protected and that revaccination was not necessary. PMID:16988640
A 12-valent Escherichia coli O-polysaccharide (O-PS)-toxin A conjugate vaccine was formulated. Nonpyrogenic, low-molecular-weight O-PS was derived from lipopolysaccharides (LPS) of the following serotypes: O1, O2, O4, O6, O7, O8, O12, O15, O16, O18, O25, and O75. Individual O-PS were covalently coupled to Pseudomonas aeruginosa toxin A using adipic acid dihydrazide as a spacer molecule and carbodiimide as a coupling agent.
S. J. Cryz; J. O. Que; A. S. Cross; E. Fürer
Gangliosides, such as GM2, GD2, GD3, and 9-O-acetyl GD3, are receiving attention as targets for antibody-based and vaccine-based therapies of melanoma. GM2 appears to be a particularly immunogenic ganglioside in humans, as indicated by the presence of naturally occurring IgM anti-GM2 antibodies in approximately 5% of humans and the fact that immunization with irradiated GM2-expressing melanoma cells or purified GM2 adherent to bacillus Calmette-Guérin elicits GM2 antibodies of low to moderate titers in a high proportion of vaccinated patients. To develop vaccines that consistently induce high titers of IgM as well as IgG anti-GM2 antibodies, vaccines containing GM2 conjugated to keyhole limpet hemocyanin as the carrier protein and QS-21 as the adjuvant have been constructed. The serological response of vaccinated patients was monitored by ELISA using purified GM2 ganglioside for IgM and IgG anti-GM2 antibodies and for GM2 cell surface-reactive antibodies by immune adherence assays and cytotoxic tests (IgM antibodies) and mixed hemadsorption assays (IgG antibodies). The majority of vaccinated patients developed IgM and IgG antibodies detectable by ELISA. In most cases, the results of IgM ELISA correlated with assays for cell surface-reactive IgM antibodies. This was not true for IgG anti-GM2 antibodies, where strong discrepancies were seen between high titers in ELISA and little or no reactivity in mixed hemadsorption tests for cell surface-reactive antibodies. These IgG antibodies (and the less frequent IgM antibodies that show similar discrepancies) may be directed against GM2 determinants that are buried, hidden, or not present on GM2-expressing target cells. With regard to a major objective of ganglioside vaccines--i.e., generation of cytotoxic antibodies--the GM2-keyhole limpet hemocyanin/QS-21 vaccine is clearly superior to the previously tested GM2/bacillus Calmette-Guérin vaccine. However, variability in patient response and lack of persistence of high-titered IgM cytotoxic antibodies in many patients are problems that remain to be solved. PMID:7708728
Kitamura, K; Livingston, P O; Fortunato, S R; Stockert, E; Helling, F; Ritter, G; Oettgen, H F; Old, L J
Randomized, Controlled, Multicenter Study of the Immunogenicity and Safety of a Fully Liquid Combination Diphtheria-Tetanus Toxoid-Five-Component Acellular Pertussis (DTaP5), Inactivated Poliovirus (IPV), and Haemophilus influenzae Type b (Hib) Vaccine Compared with a DTaP3-IPV/Hib Vaccine Administered at 3, 5, and 12 Months of Age
This study compared the levels of immunogenicity and safety of diphtheria–tetanus toxoid–five-component acellular pertussis (DTaP5), inactivated poliovirus (IPV), and Haemophilus influenzae type b (Hib) (DTaP5-IPV-Hib) and DTaP3-IPV/Hib vaccines for study participants 3, 5, and 12 months of age. Post-dose 3 noninferiority criteria comparing DTaP5-IPV-Hib to DTaP3-IPV/Hib using rates of seroprotection were demonstrated against diphtheria, tetanus, and polio types 1 to 3, but not for polyribosylribitol phosphate (PRP). While PRP did not meet noninferiority criteria, the seroprotection rate and geometric mean concentration (GMC) were high, indicating a clinically robust immune response. GMCs or titers for other antigens (including pertussis) and the safety profiles were generally similar between groups. Fully liquid DTaP5-IPV-Hib can be administered using the 3-, 5-, and 12-month vaccination schedule. (This study has been registered at ClinicalTrials.gov under registration no. NCT00287092.)
Silfverdal, Sven Arne; Boisnard, Florence; Thomas, Stephane; Mwawasi, Grace; Reynolds, Donna
Pneumococcal conjugate vaccines (PCV) may reduce nasopharyngeal carriage (NPC) of Streptococcus pneumoniae vaccine strains (VT), but serotype replacement with non-vaccine strains (NVT) has been reported. Bacterial NPC after PHiD-CV vaccination was assessed in the second year of life.Open descriptive study of NPC reported for 414 subjects vaccinated at 3–5 and 12–15 months of age with PHiD-CV with or without prophylactic
Roman Prymula; Irena Hanovcova; Miroslav Splino; Pavla Kriz; Jitka Motlova; Vera Lebedova; Patricia Lommel; Eva Kaliskova; Thierry Pascal; Dorota Borys; Lode Schuerman
Background The 7-valent pneumococcal conjugate vaccine (PCV-7) was introduced in the United Kingdom in 2006 with a 2,3 and 13month schedule, and has led to large decreases in invasive pneumococcal disease (IPD) caused by the vaccine serotypes in both vaccinated and unvaccinated cohorts. We estimated the effectiveness of PCV-7 against IPD. Methods and Findings We used enhanced surveillance data, collated at the Health Protection Agency, on vaccine type (n?=?153) and non vaccine type (n?=?919) IPD cases eligible for PCV-7. The indirect cohort method, a case-control type design which uses non vaccine type cases as controls, was used to estimate effectiveness of various numbers of doses as well as for each vaccine serotype. Possible bias with this design, caused by differential serotype replacement in vaccinated and unvaccinated individuals, was estimated after deriving formulae to quantify the bias. The results showed good effectiveness, increasing from 56% (95% confidence interval (CI): -7-82) for a single dose given under one year of age to 93% (95% CI: 70-98) for two doses under one year of age plus a booster dose in the second year of life. Serotype specific estimates indicated higher effectiveness against serotypes 4, 14 and 18C and lower effectiveness against 6B. Under the assumption of complete serotype replacement by non vaccine serotypes in carriage, we estimated that effectiveness estimates may be overestimated by about 2 to 5%. Conclusions This study shows high effectiveness of PCV-7 under the reduced schedule used in the UK. This finding agrees with the large reductions seen in vaccine type IPD in recent years in England and Wales. The formulae derived to assess the bias of the indirect cohort method for PCV-7 can also be used when using the design for other vaccines that affect carriage such as the recently introduced 13 valent pneumococcal conjugate vaccine.
Andrews, Nick; Waight, Pauline A.; Borrow, Ray; Ladhani, Shamez; George, Robert C.; Slack, Mary P. E.; Miller, Elizabeth
The reactogenicity and immunogenicity of various strengths of plain and adsorbed Cl. welchii type C toxoid have been evaluated in laboratory tests and in man in Papua New Guinea. The greater antigenicity and acceptable clinical reactivity of a vaccine containing 50 total combining power units per 0.5 mm of adsorbed toxoid resulted in its selection for further field studies. PMID:231605
Walker, P D; Foster, W H; Knight, P A; Freestone, D S; Lawrence, G
Background: Infants are at the highest risk for meningococcal disease and a broadly protective and safe vaccine is an unmet need in this youngest population. We evaluated the immunogenicity and safety of a 4-dose infant/toddler regimen of MenACWY-CRM given at 2, 4, 6, and 12 months of age concomitantly with pentavalent diphtheria-tetanus-acellular pertussis-Hemophilus influenzae type b-inactivated poliovirus-combination vaccine (DTaP-IPV/Hib), hepatitis B vaccine (HBV), 7- or 13-valent conjugate pneumococcal vaccine (PCV), and measles, mumps, and rubella vaccine (MMR). Results: Four doses of MenACWY-CRM induced hSBA titers ?8 in 89%, 95%, 97%, and 96% of participants against serogroups A, C, W-135, and Y, respectively. hSBA titers ?8 were present in 76-98% of participants after the first 3 doses. A categorical linear analysis incorporating vaccine group and study center showed responses to routine vaccines administered with MenACWY-CRM were non-inferior to routine vaccines alone, except for seroresponse to the pertussis antigen fimbriae. The reactogenicity profile was not affected when MenACWY-CRM was administered concomitantly with routine vaccines. Conclusion: MenACWY-CRM administered with routine concomitant vaccinations in young infants was well tolerated and induced highly immunogenic responses against each of the serogroups without significant interference with the immune responses to routine infant vaccinations. Methods: Healthy 2 month old infants were randomized to receive MenACWY-CRM with routine vaccines (n = 258) or routine vaccines alone (n = 271). Immunogenicity was assessed by serum bactericidal assay using human complement (hSBA). Medically attended adverse events (AEs), serious AEs (SAEs) and AEs leading to study withdrawal were collected throughout the study period. PMID:24220326
Nolan, Terry M; Nissen, Michael D; Naz, Aftab; Shepard, Julie; Bedell, Lisa; Hohenboken, Matthew; Odrljin, Tatjana; Dull, Peter M
Untreated HIV infection results in severe perturbations of the B-cell population and hyporesponsiveness to vaccination. We studied associations between circulating B-cell subsets and antibody response to pneumococcal conjugate vaccine in treated and untreated HIV patients. Ninety-five HIV-infected adults were grouped according to antiretroviral therapy (ART) and CD4+ cell count as follows: 20 ART-naïve (no prior ART), 62 ART-responders (received ART, and CD4 count >500 cells/µl), and 13 impaired responders (received ART for more than 3 years, and CD4 count <500 cells/µl). All subjects were immunized twice with double-dose 7-valent pneumococcal conjugate vaccine with or without 1 mg CPG 7909 (toll-like receptor 9 agonist) at baseline and after three months. Pre-vaccination B-cell subpopulations were assessed by flow cytometry. Serum IgG concentrations for vaccine serotypes were quantified by ELISA at baseline and 3, 4, and 9 months post-vaccination. ART responders had more isotype-switched memory B cells and more marginal-zone (MZ)-like B cells compared with impaired responders. Furthermore, ART-naïve patients had higher concentration of transitional B cells and plasmablasts compared with B cells of other patient groups. The concentration of MZ-like, isotype switched memory cells and plasmablasts correlated positively with post-vaccination IgG concentration at 3, 4, and 9 months. Low concentrations of isotype-switched memory B cells was the strongest independent predictor of poor pneumococcal conjugate vaccine responsiveness, emphasizing that B-cell subset disturbances are associated with poor vaccine response among HIV-infected patients
Johannesson, Thomas G.; S?gaard, Ole S.; Tolstrup, Martin; Petersen, Mikkel S.; Bernth-Jensen, Jens M.; ?stergaard, Lars; Erikstrup, Christian
Background Conjugate vaccines in which polysaccharide antigens are covalently linked to carrier proteins belong to the most effective and safest vaccines against bacterial pathogens. State-of-the art production of conjugate vaccines using chemical methods is a laborious, multi-step process. In vivo enzymatic coupling using the general glycosylation pathway of Campylobacter jejuni in recombinant Escherichia coli has been suggested as a simpler method for producing conjugate vaccines. In this study we describe the in vivo biosynthesis of two novel conjugate vaccine candidates against Shigella dysenteriae type 1, an important bacterial pathogen causing severe gastro-intestinal disease states mainly in developing countries. Results Two different periplasmic carrier proteins, AcrA from C. jejuni and a toxoid form of Pseudomonas aeruginosa exotoxin were glycosylated with Shigella O antigens in E. coli. Starting from shake flask cultivation in standard complex medium a lab-scale fed-batch process was developed for glycoconjugate production. It was found that efficiency of glycosylation but not carrier protein expression was highly susceptible to the physiological state at induction. After induction glycoconjugates generally appeared later than unglycosylated carrier protein, suggesting that glycosylation was the rate-limiting step for synthesis of conjugate vaccines in E. coli. Glycoconjugate synthesis, in particular expression of oligosaccharyltransferase PglB, strongly inhibited growth of E. coli cells after induction, making it necessary to separate biomass growth and recombinant protein expression phases. With a simple pulse and linear feed strategy and the use of semi-defined glycerol medium, volumetric glycoconjugate yield was increased 30 to 50-fold. Conclusions The presented data demonstrate that glycosylated proteins can be produced in recombinant E. coli at a larger scale. The described methodologies constitute an important step towards cost-effective in vivo production of conjugate vaccines, which in future may be used for combating severe infectious diseases, particularly in developing countries.
Background Streptococcus pneumoniae infections, which place a considerable burden on healthcare resources, can be reduced in a cost-effective manner using a 7-valent pneumococcal conjugate vaccine (PCV-7). We compare the cost effectiveness of a 13-valent PCV (PCV-13) and a 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) with that of PCV-7 in Turkey. Methods A cost-utility analysis was conducted and a decision analytical model was used to estimate the proportion of the Turkish population <10 years old that would experience 10 mutually exclusive outcomes over the course of 1 year from a perspective of a healthcare system. Model outcomes were adjusted according to the population demographics and region-specific serotype distribution in Turkey. Health outcomes and direct healthcare costs were simulated for PCV-7, PCV-13 and PHiD-CV. Results PCV-13 and PHiD-CV are projected to have a substantial impact on pneumococcal disease in Turkey versus PCV-7, with 2,223 and 3,156 quality-adjusted life years (QALYs) and 2,146 and 2,081 life years, respectively, being saved under a 3+1 schedule. Projections of direct medical costs showed that a PHiD-CV vaccination programme would provide the greatest cost savings, offering additional savings of US$11,718,813 versus PCV-7 and US$8,235,010 versus PCV-13. Probabilistic sensitivity analysis showed that PHiD-CV dominated PCV-13 in terms of QALYs gained and cost savings in 58.3% of simulations. Conclusion Under the modeled conditions, PHiD-CV would provide the most cost-effective intervention for reducing pneumococcal disease in Turkish children.
ABSTRACT Many pathogens produce the ?-(1?6)-linked poly-N-acetylglucosamine (PNAG) surface polysaccharide that is being developed as a broadly protective antimicrobial vaccine. However, it is unknown whether systemically injected PNAG vaccines or antibodies would provide protective immunity against pathogens confined to the gastrointestinal tract such as Shiga toxin (Stx)-producing Escherichia coli (STEC), an important group of gastrointestinal (GI) pathogens for which effective immunotherapeutics are lacking. To ascertain whether systemic IgG antibody to PNAG impacts this infectious situation, a vaccine consisting of a synthetic nonamer of nonacetylated PNAG, 9GlcNH2, conjugated to the Shiga toxin 1b subunit (9GlcNH2-Stx1b) was produced. Rabbit antibodies raised to the conjugate vaccine were tested for bacterial killing and toxin neutralization in vitro and protection against infection in infant mice. Cell surface PNAG was detected on all 9 STEC isolates tested, representing 6 STEC serogroups, including E. coli O157:H7. Antibody to the 9GlcNH2-Stx1b conjugate neutralized Stx1 potently and Stx2 modestly. For O157:H7 and O104:H4 STEC strains, antibodies elicited by the 9GlcNH2-Stx1b conjugate possessed opsonic killing and bactericidal activity. Following intraperitoneal injection, antibodies to both PNAG and Stx were needed for infant mouse protection against O157 STEC. These antibodies also mediated protection against the Stx2-producing O104:H4 strain that was the cause of a recent outbreak in Germany, although sufficient doses of antibody to PNAG alone were protective against this strain in infant mice. Our observations suggest that vaccination against both PNAG and Stx, using a construct such as the 9GlcNH2-Stx1b conjugate vaccine, would be protective against a broad range of STEC serogroups.
Lu, Xi; Skurnik, David; Pozzi, Clarissa; Roux, Damien; Cywes-Bentley, Colette; Ritchie, Jennifer M.; Munera, Diana; Gening, Marina L.; Tsvetkov, Yury E.; Nifantiev, Nikolay E.; Waldor, Matthew K.; Pier, Gerald B.
The pneumococcal pilus has been shown to be an important determinant of adhesion and virulence in mouse models of colonization, pneumonia, and bacteremia. A pilus is capable of inducing protective immunity, supporting its inclusion in next-generation pneumococcal protein vaccine formulations. Whether this vaccine target is common among pneumococci in sub-Saharan Africa is uncertain. To define the prevalence and genetic diversity of type I and II pili among invasive pneumococci in Malawi prior to the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) into routine childhood immunization, we examined 188 Streptococcus pneumoniae isolates collected between 2002 and 2008 (17% serotype 1). In this region of high disease burden, we found a low frequency of invasive piliated pneumococci (14%) and pilus gene sequence diversity similar to that seen previously in multiple global pneumococcal lineages. All common serotypes with pilus were covered by PCV13 and so we predict that pilus prevalence will be reduced in the Malawian pneumococcal population after PCV13 introduction.
Gray, Katherine; Kamng'ona, Arox; Cornick, Jennifer; Bentley, Stephen D.; Heyderman, Robert S.; Everett, Dean B.
Summary: Invasive infections caused by Streptococcus pneumoniae continue to be a major cause of morbidity and mortality worldwide, especially in children under 5 years of age. In the United States, 90% of invasive pneumococcal infections in children are caused by 13 serotypes of S. pneumoniae. The licensure (in 2000) and subsequent widespread use of a heptavalent pneumococcal conjugate vaccine (PCV7) have had a significant impact on decreasing the incidence of serious invasive pneumococcal disease (IPD) in all age groups, especially in children under 2 years of age. However, the emergence of replacement non-PCV7 serotypes, especially serotype 19A, has resulted in an increase in the incidence of serious and invasive infections. In 2010, a 13-valent PCV was licensed in the United States. However, the impact that this vaccine will have on IPD remains to be seen. The objectives of this review are to discuss the epidemiology of serious and invasive pneumococcal infections in the United States in the PCV era and to review some of the pneumococcal vaccines that are in development.
We assessed known risk factors, clinical presentation, and outcome of invasive pneumococcal disease (IPD) in children 3–59 months of age after introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in England and Wales. During September 2006–March 2010, a total of 1,342 IPD episodes occurred in 1,332 children; 14.9% (198/1,332) had comorbidities. Compared with IPD caused by PCV7 serotypes (44/248; 17.7%), comorbidities were less common for the extra 3 serotypes in the 10-valent vaccine (15/299; 5.0%) but similar to the 3 additional PCV13 serotypes (45/336; 13.4%) and increased for the 11 extra serotypes in 23-valent polysaccharide vaccine (PPV23) (39/186; 21.0%) and non-PPV23 serotypes (38/138; 27.5%). Fifty-two (3.9%) cases resulted from PCV7 failure; 9 (0.7%) case-patients had recurrent IPD. Case-fatality rate was 4.4% (58/1,332) but higher for meningitis (11.0%) and children with comorbidities (9.1%). Thus, comorbidities were more prevalent in children with IPD caused by non-PCV13 serotypes and were associated with increased case fatality.
Slack, Mary P.E.; Andrews, Nick J.; Waight, Pauline A.; Borrow, Ray; Miller, Elizabeth
The pneumococcal pilus has been shown to be an important determinant of adhesion and virulence in mouse models of colonization, pneumonia, and bacteremia. A pilus is capable of inducing protective immunity, supporting its inclusion in next-generation pneumococcal protein vaccine formulations. Whether this vaccine target is common among pneumococci in sub-Saharan Africa is uncertain. To define the prevalence and genetic diversity of type I and II pili among invasive pneumococci in Malawi prior to the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) into routine childhood immunization, we examined 188 Streptococcus pneumoniae isolates collected between 2002 and 2008 (17% serotype 1). In this region of high disease burden, we found a low frequency of invasive piliated pneumococci (14%) and pilus gene sequence diversity similar to that seen previously in multiple global pneumococcal lineages. All common serotypes with pilus were covered by PCV13 and so we predict that pilus prevalence will be reduced in the Malawian pneumococcal population after PCV13 introduction. PMID:24027261
Kulohoma, Benard W; Gray, Katherine; Kamng'ona, Arox; Cornick, Jennifer; Bentley, Stephen D; Heyderman, Robert S; Everett, Dean B
A quadrivalent meningococcal serogroup A, C, W and Y conjugate vaccine (ACWY), utilising tetanus toxoid (TT) as its carrier protein (ACWY-TT; Nimenrix™, GlaxoSmithKline Vaccines, Rixensart, Belgium) has been demonstrated to be safe and immunogenic when administered to young children from 12 months of age, older children, adolescents, and adults. Administration of a single dose of ACWY-TT induces protective serum bactericidal antibodies against all four serogroups as well as good antibody persistence. Coadministration studies have demonstrated that ACWY-TT can be administered with diphtheria, tetanus, three-component acellular pertussis, hepatitis B, inactivated polio virus and Haemophilus influenzae type b conjugate vaccine (DTaP3-IPV-HBV/Hib, Infanrix™ hexa; GlaxoSmithKline Vaccines, Rixensart, Belgium); measles, mumps, rubella, varicella vaccine (Priorix-Tetra™; GlaxoSmithKline Vaccines, Rixensart, Belgium); 10-valent pneumococcal conjugate vaccine (Synflorix(®); GlaxoSmithKline Vaccines, Rixensart, Belgium); hepatitis A and B vaccine (Twinrix(®); GlaxoSmithKline Vaccines, Rixensart, Belgium); and seasonal influenza vaccine (Fluarix™; GlaxoSmithKline Vaccines, Rixensart, Belgium). Studies in young infants from 2 months of age have now commenced but immunisation with a single dose of ACWY-TT from 12 months of age is a safe and immunogenic option in the prevention of meningococcal disease. PMID:23712402
Findlow, Helen; Borrow, Ray
We report the phase III trial efficacy of 7-valent pneumococcal conjugate vaccine against clinical and culture proven otitis media (OM) among Navajo and White Mountain Apache infants. Efficacy was -0.4% (95% CI: -19.4 to 15.6) for clinically-diagnosed OM, 5.1% (95% CI: -51.5 to 40.6) for severe OM, and 64% (95% CI: -34% to 90%) for vaccine serotype pneumococcal OM suggesting that this vaccine is efficacious for pneumococcal OM in this high risk population. PMID:18162944
O'Brien, Katherine L; David, Angeline B; Chandran, Aruna; Moulton, Lawrence H; Reid, Raymond; Weatherholtz, Robert; Santosham, Mathuram
ABSTRACT. Background. A national shortage of hep- tavalent pneumococcal conjugate vaccine (PCV7) oc- curred from September 2001 through May 2003. In De- cember 2001 and January 2002, the Advisory Committee on Immunization Practices and the American Academy of Pediatrics (AAP) issued PCV7-shortage recommenda- tions, emphasizing that all health care providers decrease the number of doses for healthy children so that
Karen R. Broder; Faap Adam Macneil; Mph Shauna Malone; Mph Benjamin Schwartz; Andrew L. Baughman; Mph Trudy V. Murphy; Faap Larry K. Pickering; John S. Moran
During the 1990s, the incidence of meningococcal disease was high in the United Kingdom. This was due primarily to an increase in serogroup C disease, particularly that within the ET-37\\/ST-11 genetic lineage. Serogroup C meningococcal polysaccharide conjugate vaccines were introduced in the United Kingdom in 1999, but the sequence types of meningococci causing disease since that time have not yet
Mathew A. Diggle; Stuart C. Clarke
Before conjugate pneumococcal vaccines (PCVs) were introduced it was estimated that Streptococcus pneumoniae caused 500,000 cases of pneumonia, 50,000 cases of bacteremia and 3000 cases of meningitis annually in the United States in both children and adults. After 10 years of routine use of the 7-valent pneumococcal conjugate vaccine (PCV7) the incidence of vaccine-type pneumococcal diseases (PDs) had significantly decreased in vaccinated children (direct effect) and unvaccinated subjects of all ages (indirect effect). Second generation, higher-valent PCVs, especially 13-valent (PCV13), routinely implemented since 2010, have reduced the incidence of PDs caused by the six additional non-PCV7 serotypes, in both vaccinated and unvaccinated subjects. The licence for this vaccine has recently been extended to include adults aged 18 to 49 in Europe. Although PCV13 has an indirect effect on IPD in adults, this will probably not achieve the same level of disease control in adults and the elderly (especially those at high risk) as that obtained in vaccinated children. As highlighted in this paper, differences exist between children and adults for PD manifestations (incidence, morbidity and mortality) and serotypes isolated in nasopharyngeal carriage and diseases, so benefits from adult vaccination must be considered in this light. PCV13 induces an immune response in adults that is non-inferior for all serotypes common with the 23-valent plain polysaccharide vaccine that is currently recommended for adults and even superior for many serotypes. Although there is no evidence that this immune response translates to clinical efficacy in adults as seen in children, the results from a randomised trial in The Netherlands, expected in 2014, should provide the missing evidence. This evidence and efficient surveillance systems should provide the necessary data, essential for policy makers in their decisions on adult pneumococcal vaccination policies. PMID:24565755
Weil-Olivier, Catherine; Gaillat, Jacques
Outbred mice were vaccinated with various artificial Salmonella vaccines and subsequently challenged intraperitoneally with graded doses of virulent Salmonella typhimurium. The Salmonella vaccines used were: (i) octasaccharide, obtained by hydrolysis of the O-antigenic polysaccharide chain of S. typhimurium strain SH 4809 with phage P22-associated endo-rhamnosidase and covalently linked to either diphtheria toxin or edestine; (ii) purified outer membrane proteins (porins) from S. typhimurium; and (iii) octasaccharide covalently linked to porins. All vaccines induced significant protection against experimental infection of mice with S. typhimurium. However, vaccination with the octasaccharide-porin conjugate resulted in better protection than that obtained by vaccination with octasaccharide or porin vaccines separately. Rabbit antibodies raised against the different vaccines were also passively administered intravenously to mice. Such mice were protected against challenge with virulent S. typhimurium by antibodies specific for the S. typhimurium O-antigen or for the porins. Thus, active immunization with more than one surface component of Salmonella bacteria improved the efficacy of the vaccine. The data from the passive immunization experiments also emphasized the role of humoral immunity for protection against S. typhimurium infection. Images
Svenson, S B; Nurminen, M; Lindberg, A A
A 2 × 2 factorial trial was performed to determine the efficacy of antennal influenza vaccination of mothers plus pneumococcal conjugate vaccination of their infants against respiratory illness during early infancy. The efficacy of trivalent inactivated influenza vaccine (TIV; delivered to mothers) plus 7-valent pneumococcal vaccine (PCV7; delivered to infants) was higher than the efficacy of TIV alone or PCV7 alone. During the period of the study in which influenza was circulating, the efficacy of TIV plus PCV7 was 72.4% (95% confidence interval, 30.2%-89.1%) against febrile respiratory illness and 66.4% (95% CI, 14.3%-86.9%) against medically attended acute respiratory illness. PMID:23300160
Omer, Saad B; Zaman, Khalequ; Roy, Eliza; Arifeen, Shams E; Raqib, Rubhana; Noory, Laila; Seib, Katherine; Breiman, Robert F; Steinhoff, Mark C
To determine the immune status of persons receiving Botulinum Pentavalent (ABCDE) Toxoid and to evaluate the effectiveness of the vaccine, we surveyed immunized individuals for neutralizing antibodies to type A and to type B botulinum toxins. Just prior t...
L. S. Siegel
Background Invasive pneumococcal disease (IPD) continues to occur at high rates among Australian Aboriginal people. The seven-valent pneumococcal conjugate vaccine (7vPCV) was given in a 2-4-6-month schedule from 2001, with a 23-valent pneumococcal polysaccharide vaccine (23vPPV) booster at 18 months, and replaced with 13vPCV in July 2011. Since carriage surveillance can supplement IPD surveillance, we have monitored pneumococcal carriage in western Australia (WA) since 2008 to assess the impact of the 10-year 7vPCV program. Methods We collected 1,500 nasopharyngeal specimens from Aboriginal people living in varied regions of WA from August 2008 until June 2011. Specimens were cultured on selective media. Pneumococcal isolates were serotyped by the quellung reaction. Results Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis were carried by 71.9%, 63.2% and 63.3% respectively of children <5 years of age, and 34.6%, 22.4% and 27.2% of people ?5 years. Of 43 pneumococcal serotypes identified, the most common were 19A, 16F and 6C in children <5 years, and 15B, 34 and 22F in older people. 7vPCV serotypes accounted for 14.5% of all serotypeable isolates, 13vPCV for 32.4% and 23vPPV for 49.9%, with little variation across all age groups. Serotypes 1 and 12F were rarely identified, despite causing recent IPD outbreaks in WA. Complete penicillin resistance (MIC ?2µg/ml) was found in 1.6% of serotype 19A (5.2%), 19F (4.9%) and 16F (3.2%) isolates and reduced penicillin susceptibility (MIC ?0.125µg/ml) in 24.9% of isolates, particularly 19F (92.7%), 19A (41.3%), 16F (29.0%). Multi-resistance to cotrimoxazole, tetracycline and erythromycin was found in 83.0% of 23F isolates. Among non-serotypeable isolates 76.0% had reduced susceptibility and 4.0% showed complete resistance to penicillin. Conclusions Ten years after introduction of 7vPCV for Aboriginal Australian children, 7vPCV serotypes account for a small proportion of carried pneumococci. A large proportion of circulating serotypes are not covered by any currently licensed vaccine.
Bowman, Jacinta; Jones, Jade; Stemberger, Natalie A.; Richmond, Peter C.; Leach, Amanda J.; Lehmann, Deborah
A long-standing challenge in developing vaccines against enterotoxigenic Escherichia coli (ETEC), the most common bacteria causing diarrhea in children of developing countries and travelers to these countries, is to protect against heat-stable toxin type Ib (STa or hSTa). STa and heat-labile toxin (LT) are virulence determinants in ETEC diarrhea. LT antigens are often used in vaccine development, but STa has not been included because of its poor immunogenicity and potent toxicity. Toxic STa is not safe for vaccines, but only STa possessing toxicity is believed to be able to induce neutralizing antibodies. However, recent studies demonstrated that nontoxic STa derivatives (toxoids), after being fused to an LT protein, induced neutralizing antibodies and suggested that different STa toxoids fused to an LT protein might exhibit different STa antigenic propensity. In this study, we selected 14 STa toxoids from a mini-STa toxoid library based on toxicity reduction and reactivity to anti-native STa antibodies, and genetically fused each toxoid to a monomeric double mutant LT (dmLT) peptide for 14 STa-toxoid-dmLT toxoid fusions. These toxoid fusions were used to immunize mice and were characterized for induction of anti-STa antibody response. The results showed that different STa toxoids (in fusions) varied greatly in anti-STa antigenicity. Among them, STaN12S, STaN12T, and STaA14H were the top toxoids in inducing anti-STa antibodies. In vitro neutralization assays indicated that antibodies induced by the 3×STaN12S-dmLT fusion antigen exhibited the greatest neutralizing activity against STa toxin. These results suggested 3×STaN12S-dmLT is a preferred fusion antigen to induce an anti-STa antibody response and provided long-awaited information for effective ETEC vaccine development. PMID:24549325
Ruan, Xiaosai; Robertson, Donald C; Nataro, James P; Clements, John D; Zhang, Weiping
The immunogenicity and reactogenicity of a meningococcal serogroup C (MenC) conjugate vaccine given concomitantly with DTaP-IPV-HBV/Hib vaccine according to a two- or three-dose schedule in healthy infants was evaluated. At 1 month post-vaccination, 98% (two doses) and 100% (three doses) of subjects had serum bactericidal antibody using human complement assay (hSBA) titres > or =1:8; at 12 months of age > or =89% of subjects in each group remained seroprotected. Induction of immunological memory, as evaluated by administration of a meningococcal serogroup A/C polysaccharide vaccine challenge dose, was similar for both regimens and no interference was observed in the immune response to MenC or hepatitis B virus antigens. Reactogenicity was similar in each group. MenC conjugate vaccine given concomitantly with DTaP-IPV-HBV/Hib to healthy infants in the first year of life using a two-dose schedule is as safe and immunogenic as a three-dose regimen. PMID:18407386
Schmitt, Heinz-J; Steul, Katrin Simone; Borkowski, Astrid; Ceddia, Francesca; Ypma, Ellen; Knuf, Markus
Prescription opioid abuse is an increasing public health concern in the USA. A vaccine comprising a hapten (OXY) conjugated to the carrier protein keyhole limpet hemocyanin (OXY-KLH) has been shown to attenuate the antinociceptive effects of oxycodone. Here, the vaccine's ability to prevent acquisition of intravenous (i.v.) oxycodone self-administration was studied in rats. Effects of vaccination on oxycodone-induced changes in the expression of several genes within the mesolimbic system, which are regulated by chronic opiate use, were also examined. Vaccination with OXY-KLH reduced the proportion of rats acquiring i.v. self-administration of oxycodone under a fixed ratio (FR) 3 schedule of reinforcement compared to control rats immunized with the unconjugated KLH carrier protein. Vaccination significantly reduced the mean number of infusions at FR3, total number of infusions, and total oxycodone intake during the entire protocol. Compared to oxycodone self-administering control rats immunized with the carrier alone, rats vaccinated with the OXY-KLH immunogen showed increased levels of adenylate cyclase 5 (Adcy5) and decreased levels of early growth response protein 2 (Egr2) and the early immediate gene c-Fos in the striatum. These data suggest that vaccination with OXY-KLH can attenuate the reinforcing effects of oxycodone at a clinically-relevant exposure level. Analysis of mRNA expression identified some addiction-relevant markers that may be of interest in understanding oxycodone effects or the protection provided by vaccination.
Pravetoni, Marco; Pentel, Paul R.; Potter, David N.; Chartoff, Elena H.; Tally, Laura; LeSage, Mark G.
The main objective of this study was to investigate the booster antibody response in individuals with initially high levels of diphtheria antitoxin. Sixty individuals eligible for the routine booster by the age of 18 years each received a single dose of 5 Lf of diphtheria toxoid in diphtheria-tetanus vaccine. A double antigen ELISA was used for the assessment of the
Elena Danilova; Alexey Shiryayev; Vegard Skogen; Einar Klæboe Kristoffersen; Haakon Sjursen
Klebsiella pneumoniae is a major cause of nosocomial pneumonia, septicemia and urinary tract infections, especially in newborns, blood cancer patients, and other immunocompromised candidates. The control of K. pneumoniae is a complicated issue due to its tight pathogenesis. Immuno-prophylactic preparations, especially those directed toward the bacterium O-antigen, showed to be the most successful way to prevent the infection incidence. However, all previously proposed preparations were either of limited spectrum or non-maternal, and hence not targeting the main Klebsiella patients. Moreover, all preparations were directed only to prevent the respiratory diseases due to that pathogen. This article addresses the development of a method originally used to purify the non-capsular bacterial-endotoxins, as a new and easy method for vaccine production against K. pneumoniae. The application of this method was preceded by a biotechnological control of capsular polysaccharide production in K. pneumoniae. The new produced natural conjugate between the bacterial O-antigen and its outer membrane proteins was evaluated by physicochemical and immunological methods to investigate its purity, integrity, safety and immunogenicity. It showed to be pure, stable, safe for use, and able to elicit a protective immunoglobulin titer against different Klebsiella infections. This immune-response proved to be transferable to the offspring of the vaccinated experimental rabbits via placenta.
Ahmad, Tarek A.; Haroun, Medhat; Hussein, Ahmad A.; El Ashry, El Sayed H.; El-Sayed, Laila H.
Rationale: Debate exists about the immunogenicity and protective efficacy of antibodies produced by the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in chronic obstructive pulmonary disease (COPD). The 7-valent diphtheria-conjugated pneumococcal polysaccharide vaccine (PCV7) induces a more robust immune response than PPSV23 in healthy elderly adults. Objectives: We hypothesized that serotype-specific IgG antibody concentration and functional antibody activity would be superior after PCV7 vaccination compared with PPSV23 in moderate to severe COPD. We also posited that older age and prior PPSV23 vaccination would be associated with reduced vaccine responsiveness. Methods: One hundred twenty patients with COPD were randomized to PPSV23 (63 subjects) or PCV7 (57 subjects). IgG concentrations were determined by ELISA; functional antibody activity was assayed with a standardized opsonophagocytosis assay and reported as an opsonization killing index (OPK). Increases in serotype-specific IgG and OPK at 1 month post vaccination were compared within and between vaccine groups. Measurements and Main Results: Both vaccines were well tolerated. Within each study group, postvaccination IgG and OPK were higher than baseline (P < 0.01) for all serotypes. Adjusted for baseline levels, postvaccination IgG was higher in the PCV7 group than the PPSV23 group for all seven serotypes, reaching statistical significance for five (P < 0.05). PCV7 resulted in a higher OPK for six of seven serotypes (statistically greater for four) compared with PPSV23. In multivariate analyses, younger age, vaccine naivety, and receipt of PCV7 were associated with increased OPK responses. Conclusions: PCV7 induces a superior immune response at 1 month post vaccination compared with PPSV23 in COPD. Older age and prior PPSV23 reduce vaccine responsiveness. Clinical trial registered with www.clinicaltrials.gov (NCT00457977).
Dransfield, Mark T.; Nahm, Moon H.; Han, MeiLan K.; Harnden, Sarah; Criner, Gerard J.; Martinez, Fernando J.; Scanlon, Paul D.; Woodruff, Prescott G.; Washko, George R.; Connett, John E.; Anthonisen, Nicholas R.; Bailey, William C.
Background: Pneumonia is the leading cause of morbidity and mortality among children <5 years of age globally. Pneumococcal conjugate vaccines (PCVs) are known to provide protection against vaccine serotype pneumococcal pneumonia; uncertainty exists regarding the optimum PCV dosing schedule. Methods: We conducted a systematic review of studies published from 1994 to 2010 (supplemented post hoc with studies from 2011) documenting the effect of PCV dosing schedules on clinical and radiologically confirmed pneumonia, pneumococcal pneumonia and empyema among children of ages targeted to receive vaccine. Data on 2- and 3-dose schedules were included. Percent change of pneumonia incidence rates from baseline to most recent year post-PCV introduction was calculated. Results: We identified 42 primary citations that evaluated PCV schedules and pneumonia. Thirty-seven (88%) were from North America, Europe or Australia; 37 (88%) evaluated PCV7 and 1 (2%) PCV10. Two studies (both observational) compared multiple schedules within the study. We found evidence of reduced clinical and radiologically confirmed pneumonia incidence for all schedules, including 2+1 (1 nonrandomized trial, 5 observational studies), 3+0 (5 randomized trials, 2 observational studies) and 3+1 (5 clinical trials, 24 observational studies) schedules. The magnitude of disease impact did not differ among schedules. Evidence for impact on pneumococcal pneumonia and empyema varied. Conclusions: All schedules (2+1, 3+0 and 3+1) reduced clinical and radiologically confirmed pneumonia. Quantifying differences in pneumonia disease impact between schedules was difficult due to heterogeneity among studies in design, case definition and population. These findings support World Health Organization recommendations for 3-dose schedules administered as either 3+0 or 2+1 regimens. Pneumonia impact data are still needed on expanded serotype PCV products, developing country settings and the role for a booster dose.
Bordetella pertussis (Bp) is the causative agent of pertussis, a vaccine preventable disease occurring primarily in children. In recent years, there has been increased reporting of pertussis. Current pertussis vaccines are acellular and consist of Bp proteins including the major virulence factor pertussis toxin (Ptx), a 5-subunit exotoxin. Variation in Ptx subunit amino acid (AA) sequence could possibly affect the immune response. A blind comparative mass spectrometric (MS) analysis of commercially available Ptx as well as the chemically modified toxoid (Ptxd) from licensed vaccines was performed to assess peptide sequence and AA coverage variability as well as relative amounts of Ptx subunits. Qualitatively, there are similarities among the various sources based on AA percent coverages and MS/MS fragmentation profiles. Additionally, based on a label-free mass spectrometry-based quantification method there is differential relative abundance of the subunits among the sources.
Williamson, Yulanda M.; Moura, Hercules; Schieltz, David; Rees, Jon; Woolfitt, Adrian R.; Pirkle, James L.; Sampson, Jacquelyn S.; Tondella, Maria L.; Ades, Edwin; Carlone, George; Barr, John R.
Background The impact of the heptavalent?pneumococcal conjugate vaccine on the incidence of pneumococcal meningitis in Europe has not yet been assessed. Objective To determine whether heptavalent?pneumococcal conjugate vaccine implementation in northern France has resulted in a decrease in the incidence of pneumococcal meningitis in children. Design Multicentre retrospective cohort study from 2000 through 2005. Settings All paediatric departments of the 18 hospitals in northern France. Patients Patients <18?years of age, admitted for laboratory?confirmed pneumococcal meningitis during the study period, were included. Interventions Data were collected from medical files and the microbiological laboratories of each hospital and compared with the regional hospital discharge codes, using a capture–recapture method. Main outcome measures The study assessed and compared global and age?related incidence rates of pneumococcal meningitis in 2001 (pre?vaccine era) and 2005. Results 77 cases were found through the capture–recapture method. The incidence rate of pneumococcal meningitis varied from 1.65/100?000 children <18?years in 2001 to 0.80/100?000 children in 2005 (53% reduction, 95% CI 31 to 74; p?=?0.08). This has so far been significant only for children <2?years of age (8.9/100?000 in 2001 to 1.8/100?000 in 2005; 82% reduction, 95% CI 52 to 95; p?=?0.03). Conclusion A decline in pneumococcal meningitis has been observed in infants since heptavalent?pneumococcal conjugate vaccination began in our area.
Dubos, F; Marechal, I; Husson, M O; Courouble, C; Aurel, M; Martinot, A
The primary concern of the vaccine industry is to produce vaccines with consistent high quality. To that end, control tests are performed in all stages of manufacturing from starting materials through final vaccine lots. Many animal-based tests are included to determine the potency and safety of human vaccines. This thesis presents the results of a study to structurally characterise diphtheria
Background Thirteen-valent pneumococcal conjugate vaccine (PCV13) and 10-valent pneumococcal conjugate vaccine (PCV10) are two recently approved vaccines for the active immunization against Streptococcus pneumoniae causing invasive pneumococcal disease in infants and children. PCV13 offers broader protection against Streptococcus pneumoniae; however, PCV10 offers potential protection against non-typeable Haemophilus influenza (NTHi). We examined public health and economic impacts of a PCV10 and PCV13 pediatric national immunization programs (NIPs) in Canada. Methods A decision-analytic model was developed to examine the costs and outcomes associated with PCV10 and PCV13 pediatric NIPs. The model followed individuals over the remainder of their lifetime. Recent disease incidence, serotype coverage, population data, percent vaccinated, costs, and utilities were obtained from the published literature. Direct and indirect effects were derived from 7-valent pneumococcal vaccine. Additional direct effect of 4% was attributed to PCV10 for moderate to severe acute otitis media to account for potential NTHi benefit. Annual number of disease cases and costs (2010 Canadian dollars) were presented. Results In Canada, PCV13 was estimated to prevent more cases of disease (49,340 when considering both direct and indirect effects and 7,466 when considering direct effects only) than PCV10. This translated to population gains of 258 to 13,828 more quality-adjusted life-years when vaccinating with PCV13 versus PCV10. Annual direct medical costs (including the cost of vaccination) were estimated to be reduced by $5.7 million to $132.8 million when vaccinating with PCV13. Thus, PCV13 dominated PCV10, and sensitivity analyses showed PCV13 to always be dominant or cost-effective versus PCV10. Conclusions Considering the epidemiology of pneumococcal disease in Canada, PCV13 is shown to be a cost-saving immunization program because it provides substantial public health and economic benefits relative to PCV10.
Group B Streptococcus (GBS) type III capsular polysaccharide (CPS III) was conjugated to recombinant cholera toxin B subunit (rCTB) using three different methods which employed (i) cystamine and N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP), (ii) carbodiimide with adipic acid dihydrazide (ADH) as a spacer, or (iii) reductive amination (RA). The CPS III-rCTB conjugates were divided into large- and small-molecular-weight (M(r)) fractions, and the immunogenicities of the different preparations after intranasal (i.n.) immunization were studied in mice. Both large- and small-M(r) conjugates of CPS III-rCTB(RA) or CPS III-rCTB(ADH) induced high, almost comparable levels of CPS-specific immunoglobulin G (IgG) in serum, lungs, and vagina that were generally superior to those obtained with CPS III-rCTB(SPDP) conjugates or a CPS III and rCTB mixture. However, the smaller-M(r) conjugates of CPS III-rCTB(RA) or CPS III-rCTB(ADH) in most cases elicited a lower anti-CPS IgA immune response than the large-M(r) conjugates, and the highest anti-CPS IgA titers in both tissues and serum were obtained with the large-M(r) CPS III-rCTB(RA) conjugate. Serum IgG anti-CPS titers induced by the CPS III-rCTB(RA) conjugate had high levels of specific IgG1, IgG2a, IgG2b, and IgG3 antibodies. Based on the effectiveness of RA for coupling CPS III to rCTB, RA was also tested for conjugating GBS CPS Ia with rCTB. As for the CPS III-rCTB conjugates, the immunogenicity of CPS Ia was greatly increased by conjugation to rCTB. Intranasal immunization with a combination of CPS Ia-rCTB and CPS III-rCTB conjugates was shown to induce anti-CPS Ia and III immune responses in serum and lungs that were fully comparable with the responses to immunization with the monovalent CPS Ia-rCTB or CPS III-rCTB conjugates. These results suggest that the GBS CPS III-rCTB and CPS Ia-rCTB conjugates prepared by the RA method may be used in bivalent and possibly also in multivalent mucosal GBS conjugate vaccines. PMID:11119518
Shen, X; Lagergård, T; Yang, Y; Lindblad, M; Fredriksson, M; Holmgren, J
Reports on the bactericidal activities of antibodies to group B Neisseria meningitidis capsular polysaccharide (B PS) are conflicting. Using three different complement sources, we analyzed the bactericidal activities of sera of juvenile rhesus monkeys immunized with five conjugate vaccines of B PS synthesized by different schemes, an Escherichia coli K92 conjugate, and a noncovalent complex of B PS with group B meningococcal outer membrane vesicles (B+OMV) (S. J. N. Devi, W. D. Zollinger, P. J. Snoy, J. Y. Tai, P. Costantini, F. Norelli, R. Rappuoli, and C. E. Frasch, Infect. Immun. 65:1045-1052, 1997). With rabbit complement, nearly all preimmune sera showed relatively high bactericidal titers, and all vaccines, except the K92 conjugate, induced a fourfold or greater increase in bactericidal titers in most of the monkeys vaccinated. In contrast, with human complement, most prevaccination sera showed no bactericidal activity and in most of the vaccine groups, little or no increase in bactericidal titer was observed. However, the covalent conjugation of P BS and OMV (B-OMV) administered with and without the Ribi adjuvant induced relatively high bactericidal titers which persisted up to 30 weeks. An analysis of the specificities of bactericidal antibodies revealed that absorption with E. coli K1 cells did not change the bactericidal titer with human complement but reduced the titers observed with the rabbit and monkey complements. A significant increase in anti-lipopolysaccharide (LPS) antibodies was elicited by the B-OMV conjugates, and nearly all of the bactericidal activity with human complement could be inhibited with the purified group B meningococcal L3,7,8 LPS. B-OMV covalently coupled via adipic acid dihydrazide elicited significantly elevated levels (P < or = 0.02) of anti-OMV antibodies compared to those of the noncovalently complexed B+OMV. An initial small-scale evaluation of B PS conjugates in adult human males appears feasible, with careful monitoring, to settle the inconsistent reports of the importance of source of complement in eliciting bacteriolysis. Subsequent analysis of resultant human antibodies for bacteriolysis, opsonophagocytosis, and protective efficacy in animal models may be the first step toward answering safety- and efficacy-related concerns about B PS conjugate vaccines.
Zollinger, W D; Moran, E E; Devi, S J; Frasch, C E
The introduction of the serogroup C meningococcal (MenC) conjugate vaccination has successfully controlled the burden of disease associated with this serogroup in many countries. However, considerable inter-individual variation is observed in immune responses to MenC vaccine, and little is understood of the determinants of this variability. Previously, we reported an association between single nucleotide polymorphisms (SNPs) in TLR3 and CD44 and the persistence of MenC vaccine immunity. Here we further examine polymorphisms within these two candidate genes and immune responses to MenC vaccine. MenC-specific IgG concentrations and serum bactericidal assay (SBA) titres were measured one month after a primary course of MenC vaccination in 318 human infants. Tagging SNPs (TagSNPs) within TLR3 and CD44 were genotyped and regional imputations carried out to screen these genes for variations associated with immunological responses to MenC vaccine. This study reports an association between an exonic variant (rs3775290, P=0.025) in TLR3 and MenC IgG concentrations, as well as an association between three SNPs in CD44 (rs3794109, P=0.021; rs3794110, P=0.022; rs112762, P=0.049) and MenC SBA titres. These data support our previous findings of an association between SNPs in TLR3 and CD44, and present novel findings implicating exonic variants in these genes with MenC vaccine responses. PMID:24768503
O'Connor, Daniel; Moore, Catrin E; Snape, Matthew D; John, Tessa; Hill, Adrian V S; Pollard, Andrew J
With the emergence of multiple meningococcal serogroups in different geographic areas, broad vaccine protection from infancy\\u000a is desirable. One hundred and seventy-five infants received either two doses of a meningococcal quadrivalent (A, C, W-135,\\u000a Y) conjugate vaccine (MenACWY-CRM) at 6 and 12 months, one dose of MenACWY-CRM at 12 months, or MenC at 12 months and MenACWY-CRM\\u000a at 18 months.
S. A. Halperin; F. Diaz-Mitoma; P. Dull; A. Anemona; F. Ceddia
Polysaccharide-specific memory B cells generated by conjugate vaccines in humans conform to the CD27+IgG+ isotype-switched memory B Cell phenotype and require contact-dependent signals from bystander T cells activated by bacterial proteins to differentiate into plasma cells.
The polysaccharides (PS) surrounding encapsulated bacteria are generally unable to activate T cells and hence do not induce B cell memory (BMEM). PS conjugate vaccines recruit CD4(+) T cells via a carrier protein, such as tetanus toxoid (TT), resulting in the induction of PS-specific BMEM. However, the requirement for T cells in the subsequent activation of the BMEM at the time of bacterial encounter is poorly understood, despite having critical implications for protection. We demonstrate that the PS-specific BMEM induced in humans by a meningococcal serogroup C PS (Men C)-TT conjugate vaccine conform to the isotype-switched (IgG(+)CD27(+)) rather than the IgM memory (IgM(+)CD27(+)) phenotype. Both Men C and TT-specific BMEM require CD4(+) T cells to differentiate into plasma cells. However, noncognate bystander T cells provide such signals to PS-specific BMEM with comparable effect to the cognate T cells available to TT-specific BMEM. The interaction between the two populations is contact-dependent and is mediated in part through CD40. Meningococci drive the differentiation of the Men C-specific BMEM through the activation of bystander T cells by bacterial proteins, although these signals are enhanced by T cell-independent innate signals. An effect of the TT-specific T cells activated by the vaccine on unrelated BMEM in vivo is also demonstrated. These data highlight that any protection conferred by PS-specific BMEM at the time of bacterial encounter will depend on the effectiveness with which bacterial proteins are able to activate bystander T cells. Priming for T cell memory against bacterial proteins through their inclusion in vaccine preparations must continue to be pursued. PMID:24227777
Clarke, Edward T; Williams, Neil A; Findlow, Jamie; Borrow, Ray; Heyderman, Robert S; Finn, Adam
The capsular polysaccharide of Salmonella typhi, Vi, is an essential virulence factor and a protective vaccine for people older than 5 years. The safety and immunogenicity of two investigational Vi conjugate vaccines were evaluated in adults, 5- to 14-year-old children, and 2- to 4-year-old children in Vietnam. The conjugates were prepared with Pseudomonas aeruginosa recombinant exoprotein A (rEPA) as the
ZUZANA KOSSACZKA; FENG-YING C. LIN; VOANH HO; NGUYEN THI THANH THUY; PHAN VAN BAY; TRAN CONG THANH; DANG DUC TRACH; ARTHUR KARPAS; STEVEN HUNT; DOLORES A. BRYLA; RACHEL SCHNEERSON; JOHN B. ROBBINS; SHOUSUN C. SZU
Introduction The objective of the study was to investigate the impact of newer biologic treatments including rituximab, abatacept and tocilizumab on antibody response following pneumococcal vaccination using a 7-valent conjugate vaccine in patients with established rheumatoid arthritis (RA). Methods Patients with RA receiving rituximab, abatacept or tocilizumab as monotherapy or combined with methotrexate (MTX) participated in the study. Specific IgG antibodies against 23F and 6B serotypes were measured at vaccination and 4 to 6 weeks after vaccination using standardised ELISA. Geometric mean antibody levels (GML) were calculated. Antibody response (AR) was defined as the ratio between post- and pre-vaccination antibody levels and a positive antibody response (posAR) was AR ?2. Results In total, 88 patients were enrolled in the study. Of 55 patients treated with rituximab, 26 (46%) were on concomitant MTX. Of patients receiving abatacept (n?=?17) and tocilizumab (n?=?16) biologic treatment was given in combination with MTX in 13 (76%) and 9 (56%) patients, respectively. Patients treated with rituximab had significantly lower AR compared to those on tocilizumab, as well as compared to previously reported RA patients on MTX and controls (spondylarthropathy patients treated with NSAIDs and/or analgesics). In total, 10.3% of patients on rituximab monotherapy and no patient on rituximab?+?MTX had posAR for both serotypes. For abatacept and tocilizumab the corresponding figures were 17.6% and 50%. Conclusion In this cohort of patients with established RA, treatment with rituximab and abatacept was associated with diminished antibody response but this was most pronounced for rituximab. Pneumococcal conjugate vaccine administrated during ongoing tocilizumab treatment seems to be associated with sufficient antibody response. Pneumococcal vaccination should preferably be encouraged before initiation of rituximab or abatacept treatment. Trial registration NCT00828997 and EudraCT EU 2007-006539-29.
Background.?Although the 23-valent pneumococcal polysaccharide vaccine (PPSV23) protects against invasive disease in young healthy persons, randomized controlled trials in chronic obstructive pulmonary disease (COPD) have demonstrated no benefit in the intention-to-treat population. We previously reported that the 7-valent diphtheria-conjugated pneumococcal polysaccharide vaccine (PCV7) is safe and induced greater serotype-specific immunoglobulin G (IgG) and functional antibody than did PPSV23 1 month after vaccination. We hypothesized that these advantages would persist at 1 and 2 years. Methods.?One hundred eighty-one patients with moderate to severe COPD were randomized to receive PPSV23 (n = 90) or PCV7 (1.0 mL; n = 91). We measured IgG by enzyme-linked immunosorbent assay and assessed functional antibody activity by a standardized opsonophagocytosis assay, reported as a killing index (OPK). We determined differences in IgG and OPK between vaccine groups at 1 and 2 years. Results.?Relative to PPSV23, PCV7 induced greater OPK at both 1 and 2 years for 6 of 7 serotypes (not 19F). This response was statistically greater for 5 of 7 serotypes at 1 year and 4 of 7 at 2 years. Comparable differences in IgG were observed but were less often statistically significant. Despite meeting Centers for Disease Control and Prevention criteria for PPSV23 administration, almost 50% of individuals had never been vaccinated. No differences in the frequency of acute exacerbations, pneumonia, or hospitalization were observed. Conclusions.?PCV7 induces a greater functional antibody response than PPSV23 in patients with COPD that persists for 2 years after vaccination. This superior functional response supports testing of conjugate vaccination in studies examining clinical end points. Clinical Trials Registration: NCT00457977.
Dransfield, Mark T.; Harnden, Sarah; Burton, Robert L.; Albert, Richard K.; Bailey, William C.; Casaburi, Richard; Connett, John; Cooper, J. Allen D.; Criner, Gerard J.; Curtis, Jeffrey L.; Han, MeiLan K.; Make, Barry; Marchetti, Nathaniel; Martinez, Fernando J.; McEvoy, Charlene; Nahm, Moon H.; Niewoehner, Dennis E.; Porszasz, Janos; Reilly, John; Scanlon, Paul D.; Scharf, Steven M.; Sciurba, Frank C.; Washko, George R.; Woodruff, Prescott G.; Lazarus, Stephen C.
Streptococcus pneumoniae is one of the major causative agents of invasive infectious disease in children <5 years old globally. The aim of this study was to analyze the antimicrobial resistance and the serotype distribution of S. pneumoniae isolates from the paediatric population in Tunisia and to specify the serotypes coverage by the conjugate pneumococcal vaccines. Antimicrobial susceptibility was determined by the disk diffusion method. Minimal inhibitory concentrations of beta-lactams were determined using the E test method (AB BIODISK). Serotypes were determined by agglutination of latex particles, which identified a subset of serotypes included in pneumococcal conjugate vaccines (1, 3, 4, 5, 14) and some of the serogroups. This was followed by the Neufeld test using monovalent antisera (Statens Serum Institute) specific for the other serotypes included in pneumococcal conjugate vaccines 7, 10 and 13 (PCV7, PCV10, PCV13): 6A, 6B, 7F, 9V, 18C, 19A, 19F and 23F. During the study period, 200 invasive and 310 non-invasive pneumococcal isolates were obtained from paediatric patients ranging in age from newborn to 16 years. Among these 510 isolates, 53.4% had reduced susceptibility to penicillin. Penicillin resistance was higher among S. pneumoniae isolates recovered from samples associated with non-invasive vs. invasive disease (60.6% vs. 45%). All the strains were susceptible to pristinamycin, vancomycin, teicoplanin and fosfomycin. Serotype 14 was the most frequently isolated serotype (22.2%), followed by serotypes 19F (15.5%) and 23F (10.3%). Of all strains typed, the percentage of serotypes covered by PCV7, PCV10 and PCV13 were 66.4%, 73% and 78%, respectively (76.1% for invasive pneumococcal isolates, 79.8% for non invasive pneumococcal isolates for PVC13). Continual surveillance of antibiotic susceptibility and careful use of antibiotics are recommended. The introduction of the new conjugate vaccine should be greatly beneficial for reducing pneumococcal invasive diseases among Tunisian children. PMID:23228353
Charfi, F; Smaoui, H; Kechrid, A
molysin (rPL), with a molecular mass of 53 kDa, had a specific activity of 3 310 5 hemolytic units per mg of protein on rabbit erythrocytes and reacted identically in immunodiffusion with the antisera against native pneumolysin. The rPL was used as a protein carrier to prepare conjugate vaccine with pneumococcal type 18C polysaccharide (PS18C). The PS18C was directly coupled
JOSEPH KUO; MARIETTA DOUGLAS; HEESOO KIM REE; ANDALF A. LINDBERG; Lederle-Praxis Biologicals
Following the introduction of the pneumococcal 7-valent conjugate vaccine (PCV7) into the routine infant immunization schedule in England, Wales, and Northern Ireland, pneumococcal serotype-specific immunoglobulin G (IgG) antibody testing was offered as a clinical service to all children within the program with invasive pneumococcal disease (IPD) to confirm an adequate antibody response to PCV7. As of March 2008, serum samples taken within 14 to 90 days of vaccination had been submitted from 107 children who had received one or more doses in the second year of life. Sera were assayed by a multiplexed microsphere assay incorporating both cell wall polysaccharide and serotype 22F adsorption. A protective serotype-specific antibody level was defined as a concentration of > or = 0.35 microg/ml. Eight children failed to develop a response to their infecting serotype (6B [n = 4], 18C [n = 2], 4 [n = 1], and 14 [n = 1]), despite receiving at least three doses of PCV7 in the second year of life or two doses in the second and two or three in the first year of life. A further two children were nonresponsive to a serotype (6B) different than that causing disease. None of the 10 children had a clinical risk factor for IPD. Two had marginally low levels of total serum IgG but mounted adequate responses to the other six PCV serotypes. This serotype-specific unresponsiveness may reflect immune paralysis due to large pneumococcal polysaccharide antigen loads and/or a potential genetic basis for nonresponse to individual pneumococcal serotypes. PMID:18779338
Borrow, Ray; Stanford, Elaine; Waight, Pauline; Helbert, Matthew; Balmer, Paul; Warrington, Rosalind; Slack, Mary; George, Robert; Miller, Elizabeth
We evaluated invasive pneumococcal disease (IPD), antimicrobial resistance and nasopharyngeal colonization before and after introduction of pneumococcal conjugate vaccine (PCV7) in Alaska Natives (AN), a population with high IPD rates. We obtained IPD rates from population-based surveillance. Colonization was determined from annual surveys among rural AN of all ages and from urban children. After vaccine introduction, vaccine-type IPD rates declined
Thomas W. Hennessy; Rosalyn J. Singleton; Lisa R. Bulkow; Dana L. Bruden; Debby A. Hurlburt; Debra Parks; Matthew Moore; Alan J. Parkinson; Anne Schuchat; Jay C. Butler
We report here results of clinical trials on a birth control vaccine, consisting of a heterospecies dimer of the beta subunit of human chorionic gonadotropin (hCG) associated noncovalently with the alpha subunit of ovine luteinizing hormone and conjugated to tetanus and diphtheria toxoids as carriers, that induces antibodies of high avidity (K(a) approximately 10(10) M-1) against hCG. Fertile women exposed to conception over 1224 cycles recorded only one pregnancy at antibody titers of > 50 ng/ml (hCG bioneutralization capacity). The antibody response declines with time; fertility was regained when titers fell to < 35 ng/ml. This study presents evidence of the feasibility of a vaccine for control of human fertility.
Talwar, G P; Singh, O; Pal, R; Chatterjee, N; Sahai, P; Dhall, K; Kaur, J; Das, S K; Suri, S; Buckshee, K
Background In February 2005, the US Advisory Committee on Immunization Practices recommended the new meningococcal conjugate vaccine (MCV4) for routine use among 11- to 12-year-olds (at the preadolescent health-care visit), 14- to 15-year-olds (before high-school entry), and groups at increased risk. Vaccine distribution started in March; however, in July, the manufacturer reported inability to meet demand and widespread MCV4 shortages were reported. Our objectives were to determine early uptake patterns among target (11-12 and 14-15 year olds) and non-target (13- plus 16-year-olds) age groups. A post hoc analysis was conducted to compare seasonal uptake patterns of MCV4 with polysaccharide meningococcal (MPSV4) and tetanus diphtheria (Td) vaccines. Methods We analyzed data for adolescents 11-16 years from five managed care organizations participating in the Vaccine Safety Datalink (VSD). For MCV4, we estimated monthly and cumulative coverage during 2005 and calculated risk ratios. For MPSV4 and Td, we combined 2003 and 2004 data and compared their seasonal uptake patterns with MCV4. Results Coverage for MCV4 during 2005 among the 623,889 11-16 years olds was 10%. Coverage for 11-12 and 14-15 year olds was 12% and 11%, respectively, compared with 8% for 13- plus 16-year-olds (p < 0.001). Of the 64,272 MCV4 doses administered from March-December 2005, 73% were administered June-August. Fifty-nine percent of all MPSV4 doses and 38% of all Td doses were administered during June-August. Conclusion A surge in vaccine uptake between June and August was observed among adolescents for MCV4, MPSV4 and Td vaccines. The increase in summer-time vaccinations and vaccination of non-targeted adolescents coupled with supply limitations likely contributed to the reported shortages of MCV4 in 2005.
Opioid conjugate vaccines have shown promise in attenuating the behavioral effects of heroin or morphine in animals. The goal of this study was to extend this approach to oxycodone (OXY), a commonly abused prescription opioid. Haptens were generated by adding tetraglycine (Gly)4 or hemisuccinate (HS) linkers at the 6-position of OXY. Immunization of rats with OXY(Gly)4 conjugated to the carrier proteins bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH) produced high-titer antibodies to OXY and its metabolite oxymorphone with substantially lower affinities for other structurally related opioid agonists and antagonists. There was no measurable binding of antibody by the (Gly)4 linker alone or off-target opioids methadone and buprenorphine. OXY(HS) conjugates were less immunogenic despite achieving protein haptenation ratios comparable to OXY(Gly)4-BSA. In rats given a single intravenous dose of OXY, immunization with OXY(Gly)4-KLH increased OXY protein binding and retention in serum while decreasing its unbound (free) concentration in plasma and distribution to brain. Vaccine efficacy correlated with serum antibody titers, and it was greatest in rats given the lowest OXY dose (0.05 mg/kg) but was significant even after a larger OXY dose (0.5 mg/kg), equivalent to the high end of the therapeutic range in humans. These effects of OXY(Gly)4-KLH on drug disposition were comparable to those of nicotine or cocaine vaccines that are in clinical trials as addiction treatments. Immunization with OXY(Gly)4-KLH also reduced OXY analgesia in a thermal nociception test. These data support further study of vaccination with the OXY(Gly)4-KLH immunogen as a potential treatment option for OXY abuse or addiction.
Le Naour, M.; Harmon, T. M.; Tucker, A. M.; Portoghese, P. S.; Pentel, P. R.
Opioid conjugate vaccines have shown promise in attenuating the behavioral effects of heroin or morphine in animals. The goal of this study was to extend this approach to oxycodone (OXY), a commonly abused prescription opioid. Haptens were generated by adding tetraglycine (Gly)(4) or hemisuccinate (HS) linkers at the 6-position of OXY. Immunization of rats with OXY(Gly)(4) conjugated to the carrier proteins bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH) produced high-titer antibodies to OXY and its metabolite oxymorphone with substantially lower affinities for other structurally related opioid agonists and antagonists. There was no measurable binding of antibody by the (Gly)(4) linker alone or off-target opioids methadone and buprenorphine. OXY(HS) conjugates were less immunogenic despite achieving protein haptenation ratios comparable to OXY(Gly)(4)-BSA. In rats given a single intravenous dose of OXY, immunization with OXY(Gly)(4)-KLH increased OXY protein binding and retention in serum while decreasing its unbound (free) concentration in plasma and distribution to brain. Vaccine efficacy correlated with serum antibody titers, and it was greatest in rats given the lowest OXY dose (0.05 mg/kg) but was significant even after a larger OXY dose (0.5 mg/kg), equivalent to the high end of the therapeutic range in humans. These effects of OXY(Gly)(4)-KLH on drug disposition were comparable to those of nicotine or cocaine vaccines that are in clinical trials as addiction treatments. Immunization with OXY(Gly)(4)-KLH also reduced OXY analgesia in a thermal nociception test. These data support further study of vaccination with the OXY(Gly)(4)-KLH immunogen as a potential treatment option for OXY abuse or addiction. PMID:22262924
Pravetoni, M; Le Naour, M; Harmon, T M; Tucker, A M; Portoghese, P S; Pentel, P R
... doses of diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccine for infants and children. One dose ... Print page Abbreviations DTaP=Pediatric - Diphtheria-Tetanus-acellular Pertussis vaccine DT=Pediatric - Diphtheria-Tetanus vaccine Td=Older ...
Background Elderly people do not mount strong immune responses to vaccines. We compared 23-valent capsular polysaccharide (23vPPV) alone versus 7-valent conjugate (PCV7) vaccine followed by 23vPPV 6 months later in hospitalized elderly. Methods Participants were randomized to receive 23vPPV or PCV7-23vPPV. Antibodies against serotypes 3, 4, 6A, 6B, 9V, 14, 18C, 19A, 19F, 23F were measured by enzyme-linked immunosorbent (ELISA) and opsonophagocytic (OPA) assays at baseline, 6 months and 12 months. Results Of 312 recruited, between 40% and 72% of subjects had undetectable OPA titres at baseline. After one dose, PCV7 recipients had significantly higher responses to serotypes 9V (both assays) and 23F (OPA only), and 23vPPV recipients had significantly higher responses to serotype 3 (ELISA), 19F and 19A (OPA only). In subjects with undetectable OPA titres at baseline, a proportionately greater rise in OPA titre (P<0.01) was seen for all serotypes after both vaccines. The GMT ratio of OPA was significantly higher at 12 months in the PCV7-23vPPV group for serotypes 6A, 9V, 18C and 23F. OPA titre levels for these serotypes increased moderately after 6 months, whereas immunity waned in the 23vPPV only arm. Conclusion We did not show overwhelming benefit of one vaccine over the other. Low baseline immunity does not preclude a robust immune response, reiterating the importance of vaccinating the frail elderly. A schedule of PCV7-23vPPV prevents waning of antibody, suggesting that both vaccines could be useful in the elderly. Follow up studies are needed to determine persistence of immunity. Trial Registration The Australian Clinical Trials Registry ACTRN12607000387426
MacIntyre, C. Raina; Ridda, Iman; Gao, Zhanhai; Moa, Aye M.; McIntyre, Peter B.; Sullivan, John S.; Jones, Thomas R.; Hayen, Andrew; Lindley, Richard I.
Background A 9-valent pneumococcal conjugate vaccine (PCV-9), given in a 3-dose schedule, protected Gambian children against pneumococcal disease and reduced nasopharyngeal carriage of pneumococci of vaccine serotypes. We have studied the effect of a booster or delayed primary dose of 7-valent conjugate vaccine (PCV-7) on antibody and nasopharyngeal carriage of pneumococci 3–4 years after primary vaccination. Methodology/Principal Findings We recruited a subsample of children who had received 3 doses of either PCV-9 or placebo (controls) into this follow-up study. Pre- and post- PCV-7 pneumococcal antibody concentrations to the 9 serotypes in PCV-9 and nasopharyngeal carriage of pneumococci were determined before and at intervals up to 18 months post-PCV-7. We enrolled 282 children at a median age of 45 months (range, 38–52 months); 138 had received 3 doses of PCV-9 in infancy and 144 were controls. Before receiving PCV-7, a high proportion of children had antibody concentrations >0.35 µg/mL to most of the serotypes in PCV-9 (average of 75% in the PCV-9 and 66% in the control group respectively). The geometric mean antibody concentrations in the vaccinated group were significantly higher compared to controls for serotypes 6B, 14, and 23F. Antibody concentrations were significantly increased to serotypes in the PCV-7 vaccine both 6–8 weeks and 16–18 months after PCV-7. Antibodies to serotypes 6B, 9V and 23F were higher in the PCV-9 group than in the control group 6–8 weeks after PCV-7, but only the 6B difference was sustained at 16–18 months. There was no significant difference in nasopharyngeal carriage between the two groups. Conclusions/Significance Pneumococcal antibody concentrations in Gambian children were high 34–48 months after a 3-dose primary infant vaccination series of PCV-9 for serotypes other than serotypes 1 and 18C, and were significantly higher than in control children for 3 of the 9 serotypes. Antibody concentrations increased after PCV-7 and remained raised for at least 18 months.
Akinsola, Adebayo K.; Ota, Martin O. C.; Enwere, Godwin C.; Okoko, Brown J.; Zaman, Syed M. A.; Saaka, Mark; Nsekpong, Ekpedeme D.; Odutola, Aderonke A.; Greenwood, Brian M.; Cutts, Felicity T.; Adegbola, Richard A.
Background A recently developed 10-valent pneumococcal non-typeable H influenzae protein D-conjugate vaccine (PHiD-CV) is expected to afford protection against more than two thirds of isolates causing IPD in children in Latin America, and also against acute otitis media caused by both Spn and NTHi. The objective of this study is to assess the cost-effectiveness of PHiD-CV in comparison to non-vaccination in children under 10 years of age in Argentina, Brazil, Chile, Colombia, Mexico and Peru. Methods We used a static, deterministic, compartmental simulation model. The dosing regimen considered included three vaccine doses (at 2 months, 4 months and 6 months) and a booster dose (at 13 months) (3?+?1 schedule). Model outcomes included number of cases prevented, deaths averted, quality-adjusted life-years (QALYs) gained and costs. Discount for costs and benefits of long term sequelae was done at 3.5%, and currency reported in 2008-2009 U$S varying between countries. Results The largest effect in case prevention was observed in pneumococcal meningitis (from 27% in Peru to 47% in Colombia), neurologic sequelae after meningitis (from 38% in Peru to 65% in Brazil) and bacteremia (from 42% in Argentina to 49% in Colombia). The proportion of predicted deaths averted annually ranged from 18% in Peru to 33% in Brazil. Overall, the health benefits achieved with PHiD-CV vaccination resulted in a lower QALY loss (from 15% lower in Peru to 26% in Brazil). At a cost of USD 20 per vaccine dose, vaccination was cost-effective in all countries, from being cost saving in Chile to a maximum Incremental Cost-effectiveness Ratio of 7,088 US$ Dollars per QALY gained. Results were robust in the sensitivity analysis, and scenarios with indirect costs affected results more than those with herd immunity. Conclusions The incorporation of the 10-valent pneumococcal conjugate vaccine into routine infant immunization programs in Latin American countries could be a cost-effective strategy to improve infant population health in the region.
The effect of Haemophilus influenzae type b (Hib) meningococcal protein conjugate vaccine (Hib-OMPC; Merck, Sharp & Dohme) on oropharyngeal (OP) carriage of Hib was evaluated in Navajo and Apache Indian children, who are known to be at high risk for invasive Hib disease. We obtained 1423 OP swabs at well child visits from 1321 children 3 months to 4 years of age: 293 of the swabs were obtained from children before the administration of any Hib-OMPC; 1119 were taken after the primary vaccination series; and 11 after the booster dose. Swabs were tested for the presence of Hib capsular polysaccharide antigen by enzyme-linked immunosorbent assay. Forty of 1423 swabs were positive for Hib. Among the 40 positive swabs 5 (13%) were obtained from children who had received Hib-OMPC vaccine appropriate for age at swabbing, compared with 500 of 1383 (36%) of negative swabs. Children who were OP carriers of Hib were older than noncarriers (mean age, 13 and 9 months, respectively) and a greater proportion of carriers (48%) had symptoms of respiratory infection at the time of swabbing than noncarriers (30%). These variables were significantly related to increased risk of OP carriage of Hib when incorporated jointly in a logistic regression model: not vaccinated according to age (odds ratio 2.7, 95% confidence interval 1.00 to 7.05); increase of age in months (odds ratio 1.1, 95% confidence interval 1.02-1.10); and respiratory infection symptoms present (odds ratio 2.0, 95% confidence interval 1.06-3.77). Thus besides preventing invasive Hib disease, appropriate vaccination with Hib-OMPC appears to reduce OP carriage of Hib. PMID:8346004
Takala, A K; Santosham, M; Almeido-Hill, J; Wolff, M; Newcomer, W; Reid, R; Käyhty, H; Esko, E; Mäkelä, P H
We performed a double-blind clinical study to evaluate the safety and immunogenicity of four formulations of a DTwPHib full liquid vaccine, three of which contained fractional doses of the 10?g-dose of CRM197-Hib conjugate vaccine.A total of 261 infants were enrolled and randomised to receive at 3, 4 and 5 months of age, in a double-blind fashion, one of the four
Eda Tamm; Alessandra Veronese; Mario Contorni; Sirli Meriste; Pantaleo Nacci; Simonetta Viviani
Background The GAVI Alliance supported10-valent pneumococcal conjugate vaccine (PCV10) introduction in Kenya. We estimated the cost-effectiveness of introducing either PCV10 or the13-valent vaccine (PCV13) from a societal perspective and explored the incremental impact of including indirect vaccine effects. Methods The costs and effects of pneumococcal vaccination among infants born in Kenya in 2010 were assessed using a decision analytic model comparing PCV10 or PCV13, in turn, with no vaccination. Direct vaccine effects were estimated as a reduction in the incidence of pneumococcal meningitis, sepsis, bacteraemic pneumonia and non-bacteraemic pneumonia. Pneumococcal disease incidence was extrapolated from a population-based hospital surveillance system in Kilifi and adjustments were made for variable access to care across Kenya. We used vaccine efficacy estimates from a trial in The Gambia and accounted for serotype distribution in Kilifi. We estimated indirect vaccine protection and serotype replacement by extrapolating from the USA. Multivariable sensitivity analysis was conducted using Monte Carlo simulation. We assumed a vaccine price of US$ 3.50 per dose. Findings The annual cost of delivering PCV10 was approximately US$14 million. We projected a 42.7% reduction in pneumococcal disease episodes leading to a US$1.97 million reduction in treatment costs and a 6.1% reduction in childhood mortality annually. In the base case analysis, costs per discounted DALY and per death averted by PCV10, amounted to US$ 59 (95% CI 26–103) and US$ 1,958 (95% CI 866–3,425), respectively. PCV13 introduction improved the cost-effectiveness ratios by approximately 20% and inclusion of indirect effects improved cost-effectiveness ratios by 43–56%. The break-even prices for introduction of PCV10 and PCV13 are US$ 0.41 and 0.51, respectively. Conclusions Introducing either PCV10 or PCV13 in Kenya is highly cost-effective from a societal perspective. Indirect effects, if they occur, would significantly improve the cost-effectiveness.
Ayieko, Philip; Griffiths, Ulla K.; Ndiritu, Moses; Moisi, Jennifer; Mugoya, Isaac K.; Kamau, Tatu; English, Mike; Scott, J. Anthony G.
Clostridium difficile is the cause of emerging nosocomial infections that result in abundant morbidity and mortality worldwide. Thus, the development of a vaccine to kill the bacteria to prevent this disease is highly desirable. Several recently identified bacterial surface glycans, such as PS-I and PS-II, are promising vaccine candidates to preclude C. difficile infection. To circumvent difficulties with the generation of natural PS-I due to its low expression levels in bacterial cultures, improved chemical synthesis protocols for the pentasaccharide repeating unit of PS-I and oligosaccharide substructures were utilized to produce large quantities of well-defined PS-I related glycans. The analysis of stool and serum samples obtained from C. difficile patients using glycan microarrays of synthetic oligosaccharide epitopes revealed humoral immune responses to the PS-I related glycan epitopes. Two different vaccine candidates were evaluated in the mouse model. A synthetic PS-I repeating unit CRM197 conjugate was immunogenic in mice and induced immunoglobulin class switching as well as affinity maturation. Microarray screening employing PS-I repeating unit substructures revealed the disaccharide Rha-(1?3)-Glc as a minimal epitope. A CRM197-Rha-(1?3)-Glc disaccharide conjugate was able to elicit antibodies recognizing the C. difficile PS-I pentasaccharide. We herein demonstrate that glycan microarrays exposing defined oligosaccharide epitopes help to determine the minimal immunogenic epitopes of complex oligosaccharide antigens. The synthetic PS-I pentasaccharide repeating unit as well as the Rha-(1?3)-Glc disaccharide are promising novel vaccine candidates against C. difficile that are currently in preclinical evaluation. PMID:23795894
Martin, Christopher E; Broecker, Felix; Oberli, Matthias A; Komor, Julia; Mattner, Jochen; Anish, Chakkumkal; Seeberger, Peter H
Meningococcal group A+C capsular polysaccharide (PS) conjugate vaccines may prime for serum immunoglobulin G (IgG) memory responses to meningococcal capsular PS. It is not known whether these vaccines induce immunological memory at the mucosal level, which may be important in reducing nasopharyngeal carriage. Mucosal immune responses to meningococcal conjugate and PS vaccines in young adults were investigated. Healthy university students were randomized to receive either a groups A+C meningococcal conjugate vaccine (MACconj, n = 100) or a group A+C meningococcal PS vaccine (MACPS, n = 95). One year after the primary immunization, both groups were randomized again to receive a MACconj or a MACPS booster vaccination. Saliva samples were collected before and 1 month after the primary and booster vaccinations. Anti-meningococcal A (MenA) and C (MenC) PS IgA and IgG antibody levels were measured by a standard enzyme-linked immunosorbent assay. After the primary vaccination, salivary MenA and MenC IgG and MenA IgA concentrations were significantly increased after immunization with both MACconj and MACPS vaccines, but the salivary Men C IgA level was increased only after MACPS vaccine (P < 0.01). IgA responses to both serogroups were greater for MACPS than MACconj vaccine (P < 0.05), whereas no significant differences were seen for IgG responses. MenA IgG titers were higher after the MACPS booster in MACconj-primed subjects than after the MACPS primary vaccination, suggesting the presence of IgG memory. Antibody responses to a dose of either MACPS or MACconj were not significantly reduced in those previously given MACPS compared to the primary responses to those vaccines. Meningococcal A+C conjugate and PS vaccines induce significant mucosal responses in young adults. MACconj priming may induce IgG memory at the mucosal level, which is likely to be a reflection of an anamnestic serum IgG response. No evidence of mucosal hyporesponsiveness was observed after MACPS priming in this study.
Zhang, Q.; Lakshman, R.; Burkinshaw, R.; Choo, S.; Everard, J.; Akhtar, S.; Finn, A.
Streptococcus pneumoniae serogroup 6 is an important cause of respiratory tract disease worldwide. Vaccination with 6B polysaccharide induces antibody response to the cross-reacting serotype 6A, but the protective capacity of 6A antibodies induced in infants remains unknown. In this study, passive immunization with serum samples obtained from infants vaccinated with an octavalent polysaccharide protein conjugate vaccine, PncT, protected mice against bacteremia and/or lung infection caused by intranasal challenge with serotypes 6B and 6A. Protective infant serum samples had significantly higher serotype-specific IgG levels and opsonic activity than did nonprotective serum samples. The protective level to either serotype was approximately 1 microg of specific IgG antibodies injected per mouse (corresponding to approximately 0.3 microg/mL). The protection was strongly related to opsonophagocytic antibody levels measured in vitro. These results demonstrate that PncT induces antibodies in infants that protect mice against invasive disease caused by the homologous serotype and by the cross-reacting serotype 6A. PMID:11110649
Saeland, E; Jakobsen, H; Ingolfsdottir, G; Sigurdardottir, S T; Jonsdottir, I
Background In mid 2010, the 7-valent pneumococcal conjugate vaccine (PCV7) was replaced by the 13-valent conjugate vaccine (PCV13) for childhood immunization in Italy. Our objective in this study was to obtain a snapshot of pneumococcal carriage frequency, colonizing serotypes, and antibiotic resistance in healthy children in two Italian cities one year after PCV13 was introduced. Methods Nasopharyngeal swabs were obtained from 571 children aged 0-5 years from November 2011-April 2012. Pneumococcal isolates were serotyped and tested for antimicrobial susceptibility. Penicillin and/or erythromycin non-susceptible isolates were analyzed by Multi Locus Sequence Typing (MLST). Results Among the children examined, 81.2% had received at least one dose of PCV7 or PCV13 and 74.9% had completed the recommended vaccination schedule for their age. Among the latter, 57.3% of children had received PCV7, 27.1% PCV13, and 15.6% a combination of the two vaccines. The overall carriage rate was 32.9%, with children aged 6-35 months the most prone to pneumococcal colonization (6-23 months OR: 3.75; 95% CI: 2.19-6.43 and 24-35 months OR: 3.15, 95%CI: 2.36-4.22). A total of 184 pneumococcal isolates were serotyped and divided into PCV7 (5.4%), PCV13 (18.0%), and non-PCV13 (82.0%) serotypes. Serotypes 6C, 24F, and 19A were the most prevalent (10.3%, 8.6%, and 8.1%, respectively). The proportion of penicillin non-susceptible (MIC >0.6 mg/L) isolates was 30.9%, while 42.3% were erythromycin resistant. Non-PCV13 serotypes accounted for 75.4% and 70.8% of the penicillin and erythromycin non-susceptible isolates, respectively. Conclusions Our results revealed low rates of PCV7 and PCV13 serotypes in Italian children, potentially due to the effects of vaccination. As the use of PCV13 continues, its potential impact on vaccine serotypes such as 19A and cross-reactive serotypes such as 6C will be assessed, with this study providing a baseline for further analysis of surveillance isolates.
Camilli, Romina; Daprai, Laura; Cavrini, Francesca; Lombardo, Donatella; D'Ambrosio, Fabio; Del Grosso, Maria; Vescio, Maria Fenicia; Landini, Maria Paola; Pascucci, Maria Grazia; Torresani, Erminio; Garlaschi, Maria Laura; Sambri, Vittorio; Pantosti, Annalisa
SUMMARY A rise in invasive Haemophilus influenzae type b (Hib) infections occurred 8 years after vaccine introduction in the United Kingdom. Aspects of Hib vaccine delivery unique to the United Kingdom have been implicated. The authors developed a fully age-structured deterministic susceptible-infected-resistant-susceptible mathematical model, expressed as a set of partial differential equations, to better understand the causes of declining vaccine
J. M C VERNON; A. R. M C LEAN
The Advisory Committee on Immunization Practices (ACIP) recommends that adolescents routinely receive 1 dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine, 2 doses of meningococcal conjugate (MenACWY) vaccine, and 3 doses of human papillomavirus (HPV) vaccine.* ACIP also recommends administration of "catch-up"† vaccinations, such as measles, mumps, and rubella (MMR), hepatitis B, and varicella, and, for all persons aged ?6 months, an annual influenza vaccination. ACIP recommends administration of all age-appropriate vaccines during a single visit. To assess vaccination coverage among adolescents aged 13-17 years, CDC analyzed data from the 2013 National Immunization Survey-Teen (NIS-Teen).§ This report summarizes the results of that analysis, which show that from 2012 to 2013, coverage increased for each of the vaccines routinely recommended for adolescents: from 84.6% to 86.0% for ?1 Tdap dose; from 74.0% to 77.8% for ?1 MenACWY dose; from 53.8% to 57.3% for ?1 HPV dose among females, and from 20.8% to 34.6% for ?1 HPV dose among males. Coverage varied by state and local jurisdictions and by U.S. Department of Health and Human Services (HHS) region. Healthy People 2020 vaccination targets for adolescents aged 13-15 years were reached in 42 states for ?1 Tdap dose, 18 for ?1 MenACWY dose, and 11 for ?2 varicella doses. No state met the target for ?3 HPV doses.¶ Use of patient reminder and recall systems, immunization information systems, coverage assessment and feedback to clinicians, clinician reminders, standing orders, and other interventions can help make use of every health care visit to ensure that adolescents are fully protected from vaccine-preventable infections and cancers (5), especially when such interventions are coupled with clinicians' vaccination recommendations. PMID:25055186
Elam-Evans, Laurie D; Yankey, David; Jeyarajah, Jenny; Singleton, James A; Curtis, Robinette C; MacNeil, Jessica; Hariri, Susan
Intranasal (i.n.) vaccination is potentially the most direct method for conveying upper respiratory and mucosal immunity to respiratory pathogens. However, for unclear reasons, vaccines introduced into the nasal sinuses often have lower efficacy than vaccines administered by the more frequently used parenteral routes. We examined i.n. vaccination in a mouse immune-response model with a commonly used Haemophilus influenzae type B vaccine (Hibv) composed of the polyribosylribitol phosphate (PRP) capsule antigen conjugated to tetanus toxoid. Intranasal vaccination with Hibv using a Toll-like receptor 4 (TLR4) agonist as an adjuvant significantly increased the levels of IgA specific for the PRP capsule antigen in blood serum, saliva, and mucosal secretion specimens. In contrast, control mice vaccinated transdermally (t.d.) with Hibv did not produce significant levels of PRP-specific IgA in the blood serum and saliva, and anti-PRP IgG was increased only in serum. The i.n. and t.d. vaccinations resulted in equivalent bactericidal antibody responses in blood serum, suggesting that vaccine-derived IgG is protective against infection. Elevated levels of IgG specific for the tetanus toxoid carrier protein were measured in nasal sinuses and vaginal secretions in mice vaccinated by either the t.d. or i.n. route. Tissue culture studies confirmed that the nasopharynx-associated lymphoid tissue (NALT) was at least one of the sources of PRP-specific IgA and carrier-specific IgG within the nasal sinuses. We conclude that i.n. vaccination aided by a TLR4 agonist results in robust immune responses to both the carrier protein and bacterial polysaccharide components of the Hibv.
Cisney, Emily D.
This study reports the synthesis of the mercapto hapten (S)-N-(2-(mercaptoethyl)-6-(3-(2-(methylamino)propyl)phenoxy)hexanamide [3, (+)-METH HSMO9] and its use to prepare METH-conjugated vaccines (MCV) from maleimide activated proteins. MALDI-TOF mass spectrometry analysis of the MCV synthesized using 3 showed there was a high and controllable epitope density on two different carrier proteins. In addition, the MCV produced a substantially greater immunological response in mice than previous METH haptens, and a monoclonal antibody generated from this MCV in mice showed a very high affinity for (+)-METH (KD = 6.8 nM). The efficient covalent coupling of (+)-METH HSMO9 to the activated carrier proteins suggests this approach could be cost effective for large-scale production of MCV. In addition, the general methods described for the synthesis of (+) METH HSMO9 (3) and its use to synthesize MCV will be applicable for conjugated vaccines of small molecules and other substances of abuse such as morphine, nicotine, and cocaine.
Carroll, F. Ivy; Blough, Bruce E.; Pidaparthi, Ramakrishna R.; Abraham, Philip; Gong, Paul K.; Deng, Liu; Huang, Xiaodong; Gunnell, Melinda; Lay, Jackson O.; Peterson, Eric C.; Owens, S. Michael
Background.?We assessed the impact of 12 years of pneumococcal conjugate vaccine (PCV7) use on pneumococcal nasopharyngeal carriage and serotype-specific invasive disease potential among Native Americans. Methods.?Families were enrolled in a carriage study from 2006 to 2008; nasopharyngeal specimens and risk factor information were collected monthly for 7 visits. Pneumococcal carriage prevalence was compared with that before (1998–2000) and during (2001–2002) PCV7 introduction. We compared invasive disease incidence and carriage prevalence before and after PCV7 introduction to estimate changes in serotype-specific invasive potential. Results.?We enrolled 1077 subjects from 302 households. There was an absolute reduction in carriage prevalence of 8.0% (95% confidence interval [CI], 4.5%–11.4%) in children aged <5 years and 3.1% (95% CI, 1.1%–5.1%) in adults. In children aged <5 years, vaccine-serotype carriage prevalence decreased by 22.8% (95% CI, 20.1%–25.3%), and nonvaccine serotype (NVT) increased by 15.9% (95% CI, 12.4%–19.3%). No significant change was detected in serotype-specific invasive potential after PCV7 introduction. Conclusions.?Pneumococcal carriage prevalence decreased in all ages since PCV7 introduction; vaccine-serotype carriage has been nearly eliminated, whereas the prevalence of NVT carriage has increased. The increase in the NVT invasive disease rate seems to be proportional to the increase in colonization prevalence.
Scott, Jennifer R.; Millar, Eugene V.; Lipsitch, Marc; Moulton, Lawrence H.; Weatherholtz, Robert; Perilla, Mindy J.; Jackson, Delois M.; Beall, Bernard; Craig, Mariddie J.; Reid, Raymond; Santosham, Mathuram
The safety and immunogenicity of a Haemophilus influenzae type b polysaccharide conjugate vaccine linked to the outer membrane protein complex of Neisseria meningitidis (Hib-OMP) were evaluated among Apache and Navajo infants and children. One dose of the Hib-OMP was given to 42 children who were from 12 and 60 months of age. Ninety-two infants 6 to 8 weeks old were given one dose of Hib-OMP at the time of enrollment. A subsequent dose of the vaccine was given 2 months later and a third dose was offered between 12 and 15 months of age. All of the 12- to 60-month-old children achieved a protective antibody concentration (greater than 1 microgram/ml) 1 month postvaccination. Among the 6- to 8-week-old infants only 11% of the Apaches and 8% of Navajos had a protective anti-PRP antibody concentration prevaccination. One month post vaccination 68% of the Apaches and 69% of the Navajos had protective anti-PRP antibody concentrations. One month after the second immunization 67% of the Apaches and 75% of Navajos had protective anti-PRP concentrations. Among the infants that received the third (booster) immunization (N = 28) 74% had protective anti-PRP antibody titers just before the booster immunization. One month after the booster immunization all of the infants had protective concentrations of anti-PRP antibody. We conclude that the Hib-OMP is safe and highly immunogenic among Apache and Navajo infants and children. PMID:2062601
Santosham, M; Hill, J; Wolff, M; Reid, R; Lukacs, L; Ahonkhai, V
Nasopharyngeal Carriage Rate and Serotypes of Streptococcus pneumoniae and Antimicrobial Susceptibility in Healthy Korean Children Younger than 5 Years Old: Focus on Influence of Pneumococcal Conjugate Vaccination
Background Even after pneumococcal vaccination introduction, Streptococcus pneumoniae (pneumoccocus) is still an important cause of respiratory and invasive severe infection. Pneumococcus is resided in nasal mucosa and local or systemic infection begins with the nasal mucosa damage. We studied the indirect effect of pneumococcal conjugate vaccine (PCV) on pneumococcal nasopharyngeal carriage rates, serotypes and antimicrobial susceptibility between vaccinate and non-vaccinated children. Materials and Methods From January 2010 to October 2010, 379 healthy children under 5 years old from three university hospitals were recruited. Fully vaccinated children over 3 time doses of PCV and children with no vaccination history of PCV were enrolled, and nasopharyngeal aspirations were obtained from these children. Serotypes using multibead serotyping assay with multiplex PCR and antimicrobial susceptibility was analyzed. Antimicrobial susceptibilities were determined by the CLIS guideline. Results Two hundred seventy six children were received pneumococcal vaccination while 103 were not. 137 pneumococci were isolated from nasopharyngeal aspiration specimens. Nasal carriage rate was significantly low in vaccinated group (P-value; 0.001). Nasopharyngeal carriage rate was 28.6% (79/276) in vaccinate group and 56.3% (58/103) in non-vaccinated group. Among those vaccinated group, 13.0% (36/276) of the serotypes were vaccine or vaccine related type with the most common type 19F. In contrast, 31.1% (32/103) of the serotypes in non vaccinated group were vaccine or vaccine related type with the most common type 6A. The resistant rate of penicillin was 90.5%. For antimicrobial susceptibility, amoxicillin and amoxicillin/clavulanate showed high susceptibility (73.0%), but 19F and 19A serotypes were all resistant against amoxicillin. Conclusions High nasopharyngeal carriage rate in non vaccinated group corresponded to the result of past study. However, 19F and 19A still came up as problematic serotypes with a high carriage rate and antimicrobial resistance in both vaccinated and non vaccinated groups. Also, this study showed that the resistance rate of primary oral antimicrobial agents was increased in compared to past. For solving these problems, the selective antimicrobial use with establishment of high dose amoxicillin/clavulanate regimen and active PCV immunization should be needed. Furthermore, pneumococcal carriage and serotype study concerning with antimicrobial susceptibility should be conducted in the future in 10 or 13-valent PCV received children.
Lee, Eu Kyoung; Jun, Ja Kyung; Choi, Ui Yoon; Kwon, Hyo-Jin; Kim, Kyung-Hyo
A simple and sensitive gas chromatographic method was designed for quantitative analysis of Streptococcus pneumoniae capsular polysaccharides, activated polysaccharides, and polysaccharide conjugates. Pneumococcal serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F polysaccharide or conjugate were subjected to methanolysis in 3N hydrochloric acid in methanol followed by re-N-acetylation and trimethylsilylation. Derivatized samples were chromatographed
John S. Kim; Erin R. Laskowich; Rasappa G. Arumugham; Raymond E. Kaiser; Gregory J. MacMichael
The seven-valent pneumococcal conjugate vaccine (PCV7) has been introduced in most high-income countries, although with differences in age, timing and number of primary doses before 6 months of age and presence and timing of a booster vaccination. The objective was to determine and compare the IgG antibody levels and functionality of IgG responses (avidity and opsonophagocytoses) at 1 and 2 years of age following 2 primary doses with a booster at 11 or 24 months of age. Children received PCV7 at 2 and 4 months (2-dose group), or at 2, 4 and 11 months (2+1-dose group), or no PCV7 (controls) before 1 year of age. All children received a PCV7 dose at 24 months of age. At the age of 12 months, the 2+1-dose group had higher IgG levels and functional antibody levels, compared to the 2-dose group for all serotypes, but at 25 months the difference between the 2-dose and 2+1-dose groups had disappeared for most serotypes. The kinetics of opsonophagocytic antibodies were in line with the specific IgG antibody levels for most serotypes, although differences between the 2-dose and the 2+1-dose group were more pronounced in OPA activity as compared to the IgG levels especially at the age of 24 months. Delaying the booster dose from 11 months to 24 months after 2 primary doses resulted in significantly higher OPA GMTs one month after the booster dose. This must, however, be balanced against the risk of leaving children unboosted between the age of 11 and 24 months at a time when disease risk is still high. Local decisions about the timing of a booster dose should also take into account vaccine coverage and the indirect herd effect in a well vaccinated population. Trial registration clinicaltrials.gov Identifier: NCT00189020. PMID:24120678
van Westen, Els; Rodenburg, Gerwin D; van Gils, Elske J M; Tcherniaeva, Irina; Berbers, Guy A M; Cowell, Lucy; Goldblatt, David; Rots, Nynke Y; van den Dobbelsteen, Germie P J M; Sanders, Elisabeth A M
Microspheres composed of biocompatible, biodegradable poly(DL-lactide-co-glycolide) (DL-PLG) and staphylococcal enterotoxin B (SEB) toxoid were evaluated as a vaccine delivery system when subcutaneously injected into mice. As measured by circulating immunoglobulin G (IgG) antitoxin titers, the delivery of SEB toxoid via DL-PLG microspheres, 1 to 10 microns in diameter, induced an immune response which was approximately 500 times that seen with nonencapsulated toxoid. The kinetics, magnitude, and duration of the antitoxin response induced with microencapsulated toxoid were similar to those obtained when an equal toxoid dose was administered as an emulsion with complete Freund adjuvant. However, the microspheres did not induce the inflammation and granulomata formation seen with complete Freund adjuvant. The adjuvant activity of the microspheres was not dependent on the superantigenicity of SEB toxin and was equally effective at potentiating circulating IgG antitrinitrophenyl levels in response to microencapsulated trinitrophenyl-keyhole limpet hemocyanin. Empty DL-PLG microspheres were not mitogenic, and SEB toxoid injected as a mixture with empty DL-PLG microspheres was no more effective as an immunogen than toxoid alone. Antigen-containing microspheres 1 to 10 microns in diameter exhibited stronger adjuvant activity than those greater than 10 microns, which correlated with the delivery of the 1- to 10-microns, but not the greater than 10-microns, microspheres into the draining lymph nodes within macrophages. The antibody response induced through immunization with microencapsulated SEB toxoid was protective against the weight loss and splenic V beta 8+ T-cell expansion induced by intravenous toxin administration. These results show that DL-PLG microsphere vaccine delivery systems, which are composed of pharmaceutically acceptable components, possess a strong adjuvant activity for their encapsulated antigens. PMID:1879922
Eldridge, J H; Staas, J K; Meulbroek, J A; Tice, T R; Gilley, R M
Microspheres composed of biocompatible, biodegradable poly(DL-lactide-co-glycolide) (DL-PLG) and staphylococcal enterotoxin B (SEB) toxoid were evaluated as a vaccine delivery system when subcutaneously injected into mice. As measured by circulating immunoglobulin G (IgG) antitoxin titers, the delivery of SEB toxoid via DL-PLG microspheres, 1 to 10 microns in diameter, induced an immune response which was approximately 500 times that seen with nonencapsulated toxoid. The kinetics, magnitude, and duration of the antitoxin response induced with microencapsulated toxoid were similar to those obtained when an equal toxoid dose was administered as an emulsion with complete Freund adjuvant. However, the microspheres did not induce the inflammation and granulomata formation seen with complete Freund adjuvant. The adjuvant activity of the microspheres was not dependent on the superantigenicity of SEB toxin and was equally effective at potentiating circulating IgG antitrinitrophenyl levels in response to microencapsulated trinitrophenyl-keyhole limpet hemocyanin. Empty DL-PLG microspheres were not mitogenic, and SEB toxoid injected as a mixture with empty DL-PLG microspheres was no more effective as an immunogen than toxoid alone. Antigen-containing microspheres 1 to 10 microns in diameter exhibited stronger adjuvant activity than those greater than 10 microns, which correlated with the delivery of the 1- to 10-microns, but not the greater than 10-microns, microspheres into the draining lymph nodes within macrophages. The antibody response induced through immunization with microencapsulated SEB toxoid was protective against the weight loss and splenic V beta 8+ T-cell expansion induced by intravenous toxin administration. These results show that DL-PLG microsphere vaccine delivery systems, which are composed of pharmaceutically acceptable components, possess a strong adjuvant activity for their encapsulated antigens.
Eldridge, J H; Staas, J K; Meulbroek, J A; Tice, T R; Gilley, R M
Polysaccharide responsiveness is tested by measuring antibody responses to polysaccharide vaccines to diagnose for humoral immunodeficiency. A common assumption is that this responsiveness is biased by any previous exposure to the polysaccharides in the form of protein-coupled polysaccharide vaccines, such as those used in many childhood vaccination programmes. To examine this assumption, we investigated the effect of protein-coupled polysaccharide vaccination on subsequent polysaccharide responsiveness. HIV-infected adults (n?=?47) were vaccinated twice with protein-coupled polysaccharides and six months later with pure polysaccharides. We measured immunoglobulin G responses against three polysaccharides present in only the polysaccharide vaccine (non-memory polysaccharides) and seven recurring polysaccharides (memory polysaccharides). Responsiveness was evaluated according to the consensus guidelines published by the American immunology societies. Impaired responsiveness to non-memory polysaccharides was more frequent than to memory polysaccharides (51% versus 28%, P?=?0.015), but the individual polysaccharides did not differ in triggering sufficient responses (74% versus 77%, P?=?0.53). Closer analysis revealed important shortcomings of the current evaluation guidelines. The interpreted response? number and their specificities influenced the likelihood of impaired responsiveness in a complex manor. This influence was propelled by the dichotomous approaches inherent to the American guidelines. We therefore define a novel more robust polysaccharide responsiveness measure, the Z-score, which condenses multiple, uniformly weighted responses into one continuous variable. Using the Z-score, responsiveness to non-memory polysaccharides and memory-polysaccharides were found to correlate (R2?=?0.59, P<0.0001). We found that polysaccharide responsiveness was not biased by prior protein-coupled polysaccharide vaccination in HIV-infected adults. Studies in additional populations are warranted.
Bernth-Jensen, Jens Magnus; S?gaard, Ole Schmeltz
The endpoint used for a phase 3 pneumococcal conjugate vaccine (PCV) trial in Bohol, Philippines was radiographic consolidation. Only one (Bohol Regional Hospital, BRH) of the four surveillance hospitals had a quality control/quality assurance program (QC/QA) prior to the trial. QC/QA was initiated in the three private hospitals. Radiologists from BRH evaluated radiographs from all hospitals based on recommended standards. Four thousand nine hundred and eighty nine films were analyzed. In 2000, the proportion of good quality films was 65% and 29% in BRH and private hospitals, respectively. By 2004, these increased to 92% and 79%, respectively. Poor film quality was commonly due to absence of collimation and poor contrast. The regular QC/QA implementation was necessary to improve film quality and was particularly important in our PCV trial that used X-ray proven consolidation as an endpoint. PMID:17023097
Arcay, Jose D; Ocampo, Arnaldo F; Solis, Roger K; Oncog, Isnardo B; Diaz, Alan D; Epe, Agnes Corazon C; Cagadas, Rummel; Pabatang, Susan; Ostensen, Harald; Lucero, Marilla G
An entirely carbohydrate-based immunogen consisting of a zwitterionic polysaccharide (ZPS) PS A1 and the well-known tumor antigen Tn has been designed, synthesized, and studied for immunological effects. The PS A1 motif was included to act as an MHCII elicitor for a T-cell-dependent immune response with increased immunogenicity against tumor-associated carbohydrate antigens, providing an alternative to carrier proteins. Through the use of C57BL/6 mice, it has been shown that chemical modification of PS A1 does not alter the recognition sequence responsible for an MHCII-mediated, T-cell-dependent immune response. The Tn-PS A1 conjugate construct confers specificity toward the Tn antigen alone, and specific carbohydrate immunoglobulins, namely, IgG3, are generated from intraperitoneal immunizations with or without adjuvant. The properties of the vaccine candidate are attributed to a site-specific linking strategy that incurs significant incorporation of Tn antigen. PMID:19552408
De Silva, Ravindra A; Wang, Qianli; Chidley, Tristan; Appulage, Dananjaya K; Andreana, Peter R
Japan is now preparing to incorporate PCV-7 into the national childhood immunisation programme. Our recently published economic evaluation of using PCV-7 to the birth cohort suggests that the cost to gain one QALY is lower than the WHO's cost-effectiveness criterion for intervention. However, many countries have started to introduce PCV-13 into their national immunisation schedule replacing PCV-7 for preventing pneumococcal diseases among young children. These raise the need to appraise the 'value for money' of replacing PCV-7 with PCV-13 vaccination programme in Japan. We conducted a cost-effectiveness analysis with Markov model and calculated incremental cost effectiveness ratios (ICERs). Our base-case analyses, which assumed both PCVs have no net indirect effect and set the cost of PCV-7/PCV-13 per shot at ¥10,000 (US$125)/¥13,000 (US$163). The results show that in Base-case A (assumed PCV-13 has no additional protection against AOM compared to PCV-7), replacing PCV-7 with PCV-13 will cost ¥37,722,901 (US$471,536) or ¥35,584,455 (US$444,850) per QALY when the caregiver's productivity loss is not included or is included, respectively. While in Base-case B (assumed PCV-13 has additional protection against AOM compared to PCV-7), ¥343,830 (US$4298) per QALY or more QALY is gained by saving money without or with caregiver's productivity loss, respectively. We also find that, in Base-case B if cost per PCV-13 shot is equal to or less than that ¥17,000, then a PCV-13 vaccination programme offered to the birth cohort in Japan is likely to be a socially acceptable option compared to the current PCV-7 vaccination programme. Furthermore, if cost per PCV-13 shot is equal to or less than ¥12,000, replacing PCV-7 with PCV-13 will save money and gain more QALYs. While in Base-case A, the replacement can only be socially acceptable if cost per PCV-13 shot is equal to or less than ¥11,000. PMID:23588088
Hoshi, Shu-ling; Kondo, Masahide; Okubo, Ichiro
This work is the first attempt to quantify the overall effects of a 13-valent pneumococcal conjugate vaccine (PCV13) vaccination programme in the Dutch population taking into account all the direct and indirect effects of the vaccine on invasive pneumococcal disease. Using available Dutch data, a dynamic transmission model for the spread of pneumococci and potential subsequent invasive pneumococcal disease has been adapted to the Dutch setting. Overall, invasive pneumococcal disease cases in the Netherlands are predicted to decrease from a pre-vaccination level of 2623 cases annually to 2475, 2289, 2185, 2179, and 2178 cases annually 5-, 10-, 20-, 30-, and 40-years, respectively, post-vaccination. Therefore, vaccination with PCV13 in the Netherlands is predicted to lower invasive pneumococcal disease cases per year by up to 445 cases in the medium- to long-term. The results are quite robust for the sensitivity analyses performed on the parameters that regulate herd immunity and competition between vaccine and non-vaccine types. PMID:24694656
De Cao, Elisabetta; Melegaro, Alessia; Klok, Rogier; Postma, Maarten
This work is the first attempt to quantify the overall effects of a 13-valent pneumococcal conjugate vaccine (PCV13) vaccination programme in the Dutch population taking into account all the direct and indirect effects of the vaccine on invasive pneumococcal disease. Using available Dutch data, a dynamic transmission model for the spread of pneumococci and potential subsequent invasive pneumococcal disease has been adapted to the Dutch setting. Overall, invasive pneumococcal disease cases in the Netherlands are predicted to decrease from a pre-vaccination level of 2623 cases annually to 2475, 2289, 2185, 2179, and 2178 cases annually 5-, 10-, 20-, 30-, and 40-years, respectively, post-vaccination. Therefore, vaccination with PCV13 in the Netherlands is predicted to lower invasive pneumococcal disease cases per year by up to 445 cases in the medium- to long-term. The results are quite robust for the sensitivity analyses performed on the parameters that regulate herd immunity and competition between vaccine and non-vaccine types.
De Cao, Elisabetta; Melegaro, Alessia; Klok, Rogier; Postma, Maarten
Background Several studies have investigated the impact of 7-valent pneumococcal conjugate vaccine (PCV7) on pneumococcal (Sp) and staphylococcal (Sa) nasopharyngeal (NP) carriage. Few have investigated the impact on Haemophilus influenzae (Hi) and Moraxella catarrhalis (Mc) carriage. We aimed to compare the NP carriage rates in young children with acute otitis media (AOM) before and after PCV7 implementation in France. Methods Prior to PCV7 implementation, we performed 4 successive randomized trials with NP samples. These studies compared several antibiotic regimens for treating AOM in young children (6 to 30 months). After PCV7 implementation, to assess the impact of the vaccination program on NP flora, young children with AOM were enrolled in a prospective surveillance study. In each study, we obtained an NP sample to analyze the carriage rates of Sp, Hi, Mc and Sa and the factors influencing the carriage. Standardized history and physical examination findings were recorded; the methods used for NP swabs (sampling and cultures) were the same in all studies. Results We enrolled 4,405 children (mean age 13.9 months, median 12.8). Among the 2,598 children enrolled after PCV7 implementation, 98.3% were vaccinated with PCV7. In comparing the pre- and post-PCV7 periods, we found a slight but non-significant decrease in carriage rates of pneumococcus (AOR = 0.85 [0.69;1.05]), H. influenzae (AOR = 0.89 [0.73;1.09]) and S. aureus (AOR = 0.92 [0.70;1.19]). By contrast, the carriage rate of M. catarrhalis increased slightly but not significantly between the 2 periods (AOR = 1.08 [0.95;1.2]). Among Sp carriers, the proportion of PCV7 vaccine types decreased from 66.6% to 10.7% (P < 0.001), penicillin intermediate-resistant strains increased from 30.3% to 43.4% (P < 0.001), and penicillin-resistant strains decreased greatly from 22.8% to 3.8% (P < 0.001). The proportion of Hi ß-lactamase-producing strains decreased from 38.6% to 17.1% (P < 0.001). Conclusion The carriage rates of otopathogen species (Sp, Hi, Mc) and Sa did not significantly change in children with AOM after PCV7 implementation in France. However, we observed significant changes in carriage rates of PCV7 vaccine serotypes and penicillin non-susceptible Sp.
Background The 10-valent pneumococcal conjugate vaccine (PCV10) was introduced in Kenya in 2011. Introduction of any PCV will perturb the existing pneumococcal population structure, thus the aim was to genotype pneumococci collected in Kilifi before PCV10. Methods and Findings Using multilocus sequence typing (MLST), we genotyped >1100 invasive and carriage pneumococci from children, the largest collection genotyped from a single resource-poor country and reported to date. Serotype 1 was the most common serotype causing invasive disease and was rarely detected in carriage; all serotype 1 isolates were members of clonal complex (CC) 217. There were temporal fluctuations in the major circulating sequence types (STs); and although 1-3 major serotype 1, 14 or 23F STs co-circulated annually, the two major serotype 5 STs mainly circulated independently. Major STs/CCs also included isolates of serotypes 3, 12F, 18C and 19A and each shared ?2 MLST alleles with STs that circulate widely elsewhere. Major CCs associated with non-PCV10 serotypes were predominantly represented by carriage isolates, although serotype 19A and 12F CCs were largely invasive and a serotype 10A CC was equally represented by invasive and carriage isolates. Conclusions Understanding the pre-PCV10 population genetic structure in Kilifi will allow for the detection of changes in prevalence of the circulating genotypes and evidence for capsular switching post-vaccine implementation.
Brueggemann, Angela B.; Muroki, Beth Mbesu; Kulohoma, Benard W.; Karani, Angela; Wanjiru, Eva; Morpeth, Susan; Kamau, Tatu; Sharif, Shahnaaz; Scott, J. Anthony G.
Summary This paper examines whether previously identified community-level factors (high proportion of crowded households and/or persons below the poverty level) remain associated with childhood pneumococcal carriage in the heptavalent pneumococcal conjugate vaccine (PCV7) era. Using logistic regression, individual factors were used to develop base models to which community-level factors were added to evaluate impact on pneumococcal carriage within two pediatric study cohorts from Massachusetts (urban Boston, outside Boston). Six years after introduction of universal childhood PCV7 vaccination, we found no consistent evidence that census tract characteristics (e.g. population size and density, age and race distribution, percent participating in group child care, parental education, percent lacking in-unit plumbing, poverty, and community stability) affected odds of pneumococcal carriage when added to individual predictors (e.g. younger age, current respiratory tract infections, and attendance in group child care). How community-level factors influence carriage continues to change in the era of increasing immunization coverage.
Hsu, K. K.; Rifas-Shiman, S. L.; Shea, K. M.; Kleinman, K. P.; Lee, G. M.; Lakoma, M.; Pelton, S. I.; Finkelstein, J. A.; Huang, S. S.
Objective Sepsis in older children and adults modifies immune system function. We compared serotype-specific antibody responses to heptavalent pneumococcal conjugate vaccine (PCV7) in very low birth weight infants (<1500g,VLBW) with and without blood stream infection (BSI) during their birth hospitalization. Patients and Methods Retrospective analysis of prospectively collected data for the Neonatal Research Network study of PCV7 responses among VLBWs. Infants received PCV7 at 2, 4, and 6 months after birth with blood drawn 4–6 weeks after 3rd dose. Serotype antibodies were compared between infants with or without a history of BSI. Regression models were constructed with birth-weight groups and other confounding factors identified in the primary study. Results 244 infants completed the vaccine series and had serum antibody available; 82 had BSI. After adjustment, BSI was not associated with reduced odds of serum antibody ?0.35?g/mL. Conclusions BSI was not associated with reduced odds of WHO-defined protective PCV7 responses in VLBWs.
Wynn, James L.; Li, Lei; Cotten, C. Michael; Phelps, Dale L.; Shankaran, Seetha; Goldberg, Ronald N; Carlo, Waldemar A.; Van Meurs, Krisa; Das, Abhik; Vohr, Betty R.; Higgins, Rosemary D.; Stoll, Barbara J; D'Angio, Carl T
SUMMARY Introduction of pneumococcal conjugate and polysaccharide vaccines into the United Kingdom's routine immunization programmes is expected to change the epidemiology of invasive pneumococcal disease (IPD). We have documented the epidemiology of IPD in an English region (South West) with high-quality surveillance data before these programmes were established. We analysed data on isolates of Streptococcus pneumoniae from blood and CSF between 1996 and 2005 from microbiology laboratories in the South West that were reported and/or referred for serotyping to the Health Protection Agency Centre for Infections. The mean annual incidence of IPD increased from 11·2/100 000 in 1996 to 13·6/100 000 in 2005 (P<0·04). After adjusting for annual blood-culture sampling rates in hospitals serving the same catchment populations, an increase in annual incidence of IPD was no longer observed (P=1·0). Variation in overall incidence between laboratories could also be explained by variation in blood culture rates. The proportion of disease caused by serotypes 6B, 9V and 14 decreased significantly (P=0·001, P=0·007, and P=0·027 respectively) whereas that caused by serotype 4, 7F and 1 increased (P=0·001, P=0·003, and P<0·001 respectively) between 2000 and 2005. The level of penicillin non-susceptibility and resistance to erythromycin remained stable (2% and 12% respectively). This study provides an important baseline to assess the impact of changing vaccination programmes on the epidemiology of IPD, thus informing future use of pneumococcal vaccines.
IHEKWEAZU, C. A.; DANCE, D. A. B.; PEBODY, R.; GEORGE, R. C.; SMITH, M. D.; WAIGHT, P.; CHRISTENSEN, H.; CARTWRIGHT, K. A. V.; STUART, J. M.
The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in the United States in 2010 for the prevention of invasive pneumococcal disease (IPD) and otitis media. While many studies have reported its potential efficacy for IPD, not much is known about the epidemiology of noninvasive disease following its introduction. We characterized the capsular types and surface protein genes of noninvasive pediatric pneumococcal isolates collected between 2002 and 2010 (n = 1,058) at Children's of Alabama following the introduction of PCV7 and tested a subset of noninvasive and previously characterized IPD isolates for the presence of the pspA, pspC, and rrgC genes, which encode protection-eliciting proteins. PCV7 serotypes had dramatically decreased by 2010 (P < 0.0001), and only 50% of all noninvasive infections were caused by the PCV13 capsular serotypes. Serotype 19A accounted for 32% of the noninvasive isolates, followed by serotypes 35B (9%), 19F (7%), and 6C (6%). After 7 years of PCV7 usage, there were no changes in the frequencies of the pspA or pspC genes; 96% of the strains were positive for family 1 or 2 pspA genes, and 81% were also positive for pspC. Unexpectedly, more noninvasive than invasive strains were positive for rrgC (P < 0.0001), and the proportion of rrgC-positive strains in 2008 to 2010 was greater than that in 2002 to 2008 (IPD, P < 0.02; noninvasive, P < 0.001). Serotypes 19F, 19A, and 35B were more frequently rrgC positive (P < 0.005) than other serotypes. A vaccine containing antigens, such as PspA, PspC, and/or RrgC, can provide coverage against most non-PCV13-type pneumococci. Continued surveillance is critical for optimal future vaccine development.
Croney, Christina M.; Nahm, Moon H.; Juhn, Steven K.; Briles, David E.
To evaluate the effects of 7-valent pneumococcal conjugate vaccine (PCV7) introduction to the routine childhood immunisation schedule in 2008 and its replacement by PCV13 in 2010 in Ireland, we surveyed the serotypes and antimicrobial susceptibilities of 339 pneumococci associated with carriage and non-invasive infection (NII) in a Dublin paediatric hospital from 2009 to 2012. Furthermore, we compared the distribution of pneumococcal serotypes collected from 2009 to 2012 to 105 NII pneumococci isolated in 2007, the year before conjugate vaccine introduction. PCV7 serotypes declined from 2007 to 2012 as follows: carriage, 67-23% (p=0.0004); conjunctivitis, 58-0% (p<0.0001); non-bacteraemic lower respiratory tract infection, 50-19% (p=0.0363) and otitis media 54-27%. Notably, antimicrobial resistant (AMR) PCV7 serotypes showed a significant decrease by the end of the study period (i.e. 2012) (p<0.0001). Compared with 2007 the overall occurrence of serotype 19A increased from 1.9 to 10% in 2010 (p=0.0132) and to 15% in 2011 (p=0.0005). Importantly, serotype 19A declined significantly from 2011 levels to an overall prevalence of 4.8% in 2012 (p=0.0243). Most striking was the significant reduction of AMR 19A (p=0.0195). Conversely, increases were observed in non-vaccine type (NVT) pneumococci in 2009-2012, of which serotypes 11A (n=30), 15B/C (n=17), 22F (n=14), 35Bn=13), non-typeable pneumococci (n=13) and 23A (n=12) were the most prevalent. Moreover, an increase in NVT non-susceptible to at least one antimicrobial in 2009-2012 was noted, attributable to serotypes 35B (n=10) and 15A (n=7). In summary, this study has shown that PCV7 and PCV13 introduction has had a positive impact on their target serotypes and antimicrobial resistance amongst pneumococci within a paediatric hospital within a short time period. However, the increase in NVT prevalence highlights the need for continued surveillance. PMID:24795223
McElligott, Martha; Vickers, Imelda; Cafferkey, Mary; Cunney, Robert; Humphreys, Hilary
Many pathogens are sheltered from host immunity by surface polysaccharides that would be ideal as vaccines except that they are too similar to host antigens to be immunogenic. The production of functional IgG is a desirable response to vaccines; because IgG is the only isotype that crosses the placenta, it is of particular importance in maternal vaccines against neonatal disease due to group B Streptococcus (GBS). Clinical studies found a substantially lower proportion of IgG—relative to IgM—among antibodies elicited by conjugates prepared with purified GBS type V capsular polysaccharide (CPS) than among those evoked by CPSs of other GBS serotypes. The epitope specificity of IgG elicited in humans by a conjugate prepared with type V CPS is for chemically desialylated type V CPS (dV CPS). We studied desialylation as a mechanism for enhancing the ability of type V CPS to induce IgM-to-IgG switching. Desialylation did not affect the structural conformation of type V CPS. Rhesus macaques, whose isotype responses to GBS conjugates match those of humans, produced functionally active IgG in response to a dV CPS–tetanus toxoid conjugate (dV-TT), and 98% of neonatal mice born to dams vaccinated with dV-TT survived lethal challenge with viable GBS. Targeted chemical engineering of a carbohydrate to create a molecule less like host self may be a rational approach for improving other glycoconjugates.
Guttormsen, Hilde-Kari; Paoletti, Lawrence C.; Mansfield, Keith G.; Jachymek, Wojcieck; Jennings, Harold J.; Kasper, Dennis L.
A relaxometric investigation of a nontoxic mutant of diphtheria toxin and of its conjugates with capsular polysaccharides of different groups of Neisseria meningitidis was performed. The insertion of polysaccharides chains alters dramatically the hydrodynamic properties of the protein. The model-free analysis of the 1H nuclear magnetic relaxation dispersion profiles of their water solutions shows: i), a reduced protein hydration with respect to the carrier protein alone; ii), a much larger flexibility of the conjugates with respect to a compact macromolecule of the same molecular weight; and iii), a strong tendency to aggregate. The above findings are largely independent on the nature of the polysaccharide and thus provide a fairly general picture of the dynamic properties of glycoconjugate proteins.
Berti, Francesco; Costantino, Paolo; Fragai, Marco; Luchinat, Claudio
Pneumonia Hospitalizations Among Young Children Before and After Introduction of Pneumococcal Conjugate Vaccine - United State, 1997-2006. Morbidity and Morality Weekly Report, Vol. 58, No. 1, january 16, 2009.
Streptococcus pneumoniae is the leading bacterial cause of community-acquired pneumonia hospitalizations and an important cause of bacteremia and meningitis, especially among young children and older adults. A 7-valent pneumococcal conjugate vaccine (PCV7...
Antigenicities of several formalin-detoxified botulinum neurotoxin preparations were measured by inhibition and sandwich enzyme-linked immunosorbent assay (ELISA), and immunogenicity was studied in mice. The toxoids were derived primarily from the serotype A 150-kDa neurotoxin protein, while one toxoid was derived from the naturally occurring 900-kDa toxin-hemagglutinin complex. Antigenicity was severely compromised in two commercially available toxoids. A variety of new
James E. Keller
Background Vaccine-serotype (VT) invasive pneumococcal disease (IPD) rates declined substantially following introduction of 7-valent pneumococcal conjugate vaccine (PCV7) into national immunization programs. Increases in non-vaccine-serotype (NVT) IPD rates occurred in some sites, presumably representing serotype replacement. We used a standardized approach to describe serotype-specific IPD changes among multiple sites after PCV7 introduction. Methods and Findings Of 32 IPD surveillance datasets received, we identified 21 eligible databases with rate data ?2 years before and ?1 year after PCV7 introduction. Expected annual rates of IPD absent PCV7 introduction were estimated by extrapolation using either Poisson regression modeling of pre-PCV7 rates or averaging pre-PCV7 rates. To estimate whether changes in rates had occurred following PCV7 introduction, we calculated site specific rate ratios by dividing observed by expected IPD rates for each post-PCV7 year. We calculated summary rate ratios (RRs) using random effects meta-analysis. For children <5 years old, overall IPD decreased by year 1 post-PCV7 (RR 0·55, 95% CI 0·46–0·65) and remained relatively stable through year 7 (RR 0·49, 95% CI 0·35–0·68). Point estimates for VT IPD decreased annually through year 7 (RR 0·03, 95% CI 0·01–0·10), while NVT IPD increased (year 7 RR 2·81, 95% CI 2·12–3·71). Among adults, decreases in overall IPD also occurred but were smaller and more variable by site than among children. At year 7 after introduction, significant reductions were observed (18–49 year-olds [RR 0·52, 95% CI 0·29–0·91], 50–64 year-olds [RR 0·84, 95% CI 0·77–0·93], and ?65 year-olds [RR 0·74, 95% CI 0·58–0·95]). Conclusions Consistent and significant decreases in both overall and VT IPD in children occurred quickly and were sustained for 7 years after PCV7 introduction, supporting use of PCVs. Increases in NVT IPD occurred in most sites, with variable magnitude. These findings may not represent the experience in low-income countries or the effects after introduction of higher valency PCVs. High-quality, population-based surveillance of serotype-specific IPD rates is needed to monitor vaccine impact as more countries, including low-income countries, introduce PCVs and as higher valency PCVs are used. Please see later in the article for the Editors' Summary
Feikin, Daniel R.; Kagucia, Eunice W.; Loo, Jennifer D.; Link-Gelles, Ruth; Puhan, Milo A.; Cherian, Thomas; Levine, Orin S.; Whitney, Cynthia G.; O'Brien, Katherine L.; Moore, Matthew R.
... 4–6 months. Diphtheria and Tetanus Toxoid and Pertussis Vaccine Diphtheria, tetanus, and pertussis each occur worldwide and are endemic in countries ... before traveling. Optimum protection against diphtheria, tetanus, and pertussis is achieved with ?3 but preferably 4 doses ...
Evidence for induction of polysaccharide specific B-cell-memory in the 1st year of life: plain Haemophilus influenzae type b - PRP (Hib) boosters children primed with a tetanus-conjugate Hib-DTPa-HBV combined vaccine
The lack of an adequate immune response to the major polysaccharide of the Haemophilus influenzae type b (Hib) capsule (polyribosyl ribitol phosphate) (PRP) in very young infants (18 months) can be overcome by conjugating\\u000a PRP to a T-cell dependent carrier protein. We studied whether administration of a tetanus-PRP conjugate vaccine reconstituted\\u000a with a diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine as a
F. Zepp; H.-J. Schmitt; A. Kaufhold; A. Schuind; M. Knuf; P. Habermehl; C. Meyer; H. Bogaerts; M. Slaoui; R. Clemens
There is no licensed vaccine for the prevention of shigellosis. Our approach to the development of Shigella vaccine is based on inducing serum IgG antibodies to the O-specific polysaccharide (O-SP) domain of their lipopolysaccharides (LPS). We have shown that low molecular mass O-SP-core (O-SPC) fragments isolated from Shigella sonnei LPS conjugated to proteins induced significantly higher antibody levels in mice than the full length O-SP conjugates. This finding is now extended to the O-SPC of S. flexneri 2a and 6, and S. dysenteriae type 1. The structures of O-SPC, containing core plus 1–4 O-SP repeat units (RU), were analyzed by NMR and mass spectroscopy. The first RUs attached to the cores of S. flexneri 2a and 6 LPS were different from the following RUs in their O-acetylation and/or glucosylation. Conjugates of core plus more than 1 RUs were necessary to induce LPS antibodies in mice. The resulting antibody levels were comparable to those induced by the full length O-SP conjugates. In S. dysenteriae type 1, the first RU was identical to the following RUs, with the exception that the GlcNAc was bound to the core in the ?-configuration, while in all other RUs the GlcNAc was present in the ?-configuration. In spite of this difference, conjugates of S. dysenteriae type 1 core with 1, 2, or 3 RUs induced LPS antibodies in mice with levels statistically higher than those of the full size O-SP conjugates. O-SPC conjugates are easy to prepare, characterize, and standardize, and their clinical evaluation is planned.
Kubler-Kielb, Joanna; Vinogradov, Evgeny; Mocca, Christopher; Pozsgay, Vince; Coxon, Bruce; Robbins, John B.; Schneerson, Rachel
MenAfriVac™ is a conjugate vaccine against meningitis A specifically designed for Africa. In Niger, the MenAfriVac™ vaccination campaign was conducted in people aged 1-29 years in three phases. The third phase was conducted in November/December 2011 targeting more than 7 million people. We estimated vaccination coverage for the third phase; classified the 31 target districts according to vaccination coverage levels; analysed the factors associated with being vaccinated; described the reasons for non-vaccination; and estimated coverage of the MenAfriVac™ introduction in Niger by aggregating data from all three phases. We classified the districts by clustered lot quality assurance sampling according to a 75% lower threshold and a 90% upper threshold. We estimated coverage using a minimum cluster-sample of 30 x 10 in each region. Two criteria were used to document vaccination status: presentation of vaccination card only or by card and/or verbal history of vaccination (card+history). We surveyed 2390 persons. After the third phase, estimated coverage was 68.8% (95% CI 64.9-72.8) by card only and 90.9% (95% CI 88.6-93.2) by card+history. Five districts were accepted for coverage above 75% based on card only, whereas 25 were accepted based on card+history. Factors positively associated with being vaccinated were younger age (<15 years), female sex, residing in the same household for more than three months, and being informed about the vaccination campaign. The main reason for non-vaccination was not being at home during the campaign. Overall coverage for MenAfriVac™ introduction via 3 phases was 76.1% (95% CI: 72.5-79.6) by card only and 91.9% (95%CI: 89.7-94.1) by card+history.Although estimated coverage was high, pockets of non-vaccination probably still exist in the country; thus, the implementation of mop-up campaigns should be considered. Priorities for the future should include incorporating meningitis A vaccination into the existing immunization schedule and assessing its impact at a population level. PMID:23337027
Caini, Saverio; Beck, Nam Seon; Yacouba, Harouna; Maiga, Idrissa; Chaibou, Ibrahim; Hinsa, Ide; Adakal, Aboubacar; Issoufou, Aboubacar; Kim, Sung Hye; Pezzoli, Lorenzo
Edema disease (ED) in piglets is caused by Shiga toxin Stx2e-producing Escherichia coli. We show that a genetically disarmed Stx2e toxoid is a safe antigen that generates antiserum protecting piglets against the Stx2e toxin. Immunization of suckling piglets with the Stx2e toxoid was safe, had no adverse effects on growth of the piglets, and resulted in effective prevention of edema disease clinical symptoms after challenge with the Stx2e toxin. Our data showed that maternal immunity against the Stx2e toxoid can be transmitted from the vaccinated sows to the piglets via the colostrum. Very high levels of Stx2e-specific serum antibodies persisted in these piglets until 1 month postweaning, bridging the critical period in which the weaned piglets are most susceptible to edema infection. Challenge with Stx2e toxin resulted in clinical signs of edema disease and death of all control piglets from nonimmunized sows, whereas none of the piglets from immunized sows developed clinical signs of ED.
Oanh, Thi Kim Nguyen; Nguyen, Viet Khong; De Greve, Henri
BACKGROUND: The study describes the molecular epidemiology of Streptococcus pneumoniae causing invasive disease in Gambian children METHODS: One hundred and thirty-two S. pneumoniae isolates were recovered from children aged 2–29 months during the course of a pneumococcal conjugate vaccine trial conducted in The Gambia of which 131 were characterized by serotyping, antibiotic susceptibility, BOX-PCR and MLST. RESULTS: Twenty-nine different serotypes
Martin Antonio; Hannah Dada-Adegbola; Ekow Biney; Tim Awine; John O'Callaghan; Valentin Pfluger; Godwin Enwere; Brown Okoko; Claire Oluwalana; Adeola Vaughan; Syed MA Zaman; Gerd Pluschke; Brian M Greenwood; Felicity Cutts; Richard A Adegbola
Methods We undertook a randomised, placebo-controlled, double-blind trial in eastern Gambia. Children age 6-51 weeks were randomly allocated three doses of either pneumococcal conjugate vaccine (n=8718) or placebo (8719), with intervals of at least 25 days between doses. Our primary outcome was first episode of radiological pneumonia. Secondary endpoints were clinical or severe clinical pneumonia, invasive pneumococcal disease, and all-cause
FT Cutts; SMA Zaman; G Enwere; S Jaffar; OS Levine; JB Okoko; C Oluwalana; A Vaughan; SK Obaro; A Leach; KP McAdam; E Biney; M Saaka; U Onwuchekwa; F Yallop; NF Pierce; BM Greenwood; RA Adegbola
Human immunodeficiency virus (HIV)-infected patients have an increased rate of pneumococcal infections. Within the HIV-infected population, patients with low CD4 cell counts have a higher rate of pneumococcal infection. The purpose of our study was to determine pneumococcal carriage and to examine the serotypes carried by HIV-infected patients after the introduction of the conjugate vaccine. Nasopharyngeal swabs were obtained from
Chinwendu Onwubiko; Edwin Swiatlo; Larry S. McDaniel
Pneumococcal conjugate vaccines (PCV) may reduce nasopharyngeal carriage (NPC) of Streptococcus pneumoniae vaccine strains (VT), but serotype replacement with non-vaccine strains (NVT) has been reported. Bacterial NPC after PHiD-CV vaccination was assessed in the second year of life. Open descriptive study of NPC reported for 414 subjects vaccinated at 3-5 and 12-15 months of age with PHiD-CV with or without prophylactic paracetamol (PP) compared to 336 age-matched PCV-naïve controls. Carriage was assessed prior to and 1, 3, 7 and 12 months after PHiD-CV booster or MenACWY-TT control vaccination at 12-15 months of age. At each visit, carriage of VT was reduced by 22-35% in PHiD-CV recipients. Vaccine efficacy across all visits was 21.7% [95% CI 2.6; 37.0] (26.8% carriage in the PHiD-CV group versus 34.2% in controls). Carriage rates of NVT tended to be higher in PHiD-CV recipients. Pre-booster, these findings were more pronounced when PP had not been administered. No substantial effect of PHiD-CV vaccination was observed on NPC of other bacterial pathogens including non-typeable Haemophilus influenzae. Primary and booster vaccination with PHiD-CV reduced NPC of VT in the second year of life and tended to slightly increase that of NVT in line with previous experience with the 7-valent PCV. PMID:21215830
Prymula, Roman; Hanovcova, Irena; Splino, Miroslav; Kriz, Pavla; Motlova, Jitka; Lebedova, Vera; Lommel, Patricia; Kaliskova, Eva; Pascal, Thierry; Borys, Dorota; Schuerman, Lode
Major epidemics of serogroup A meningococcal meningitis continue to affect the African meningitis belt. The development of an affordable conjugate vaccine against the disease became a priority for World Health Organization (WHO) in the late 1990s. Licensing of meningococcal vaccines has been based on serological correlates of protection alone, but such correlates might differ in different geographical regions. If high pre-vaccination antibody concentrations/titers impacts on the response to vaccination and possibly vaccine efficacy, is not clearly understood. We set out to define the pre-vaccination Meningococcal group A (Men A) antibody concentrations/titers in The Gambia and study their impact on the immunogenicity of Men A containing vaccines. Data from subjects originally enrolled in studies to test the safety and immunogenicity of the MenA vaccine recently developed for Africa meningococcal A polysaccharide conjugated to tetanus toxoid, MenAfriVac(®) (PsA-TT) were analyzed. Participants had been randomized to receive either the study vaccine PsA-TT or the reference quadrivalent plain polysaccharide vaccine containing meningococcal groups A, C, W, and Y, Mencevax(®) ACWY, GlaxoSmithKline (PsACWY) in a 2:1 ratio. Venous blood samples were collected before and 28 days after vaccination. Antibodies were assayed by enzyme-linked immunosorbent assay (ELISA) for geometric mean concentrations and serum bactericidal antibody (SBA) for functional antibody. The inter age group differences were compared using ANOVA and the pre and post-vaccination differences by t test. Over 80% of the ?19 year olds had pre-vaccination antibody concentrations above putatively protective concentrations as compared to only 10% of 1-2 year olds. Ninety-five percent of those who received the study vaccine had ?4-fold antibody responses if they had low pre-vaccination concentrations compared to 76% of those with high pre-vaccination concentrations. All subjects with low pre-vaccination titers attained ?4-fold responses as compared to 76% with high titers where study vaccine was received. Our data confirm the presence of high pre-vaccination Men A antibody concentrations/titers within the African meningitis belt, with significantly higher concentrations in older individuals. Although all participants had significant increase in antibody levels following vaccination, the four-fold or greater response in antibody titers were significantly higher in individuals with lower pre-existing antibody titers, especially after receiving PsA-TT. This finding may have some implications for vaccination strategies adopted in the future. PMID:24863486
Idoko, Olubukola T; Okolo, Seline N; Plikaytis, Brian; Akinsola, Adebayo; Viviani, Simonetta; Borrow, Ray; Carlone, George; Findlow, Helen; Elie, Cheryl; Kulkarni, Prasad S; Preziosi, Marie-Pierre; Ota, Martin; Kampmann, Beate
With the emergence of multiple meningococcal serogroups in different geographic areas, broad vaccine protection from infancy is desirable. One hundred and seventy-five infants received either two doses of a meningococcal quadrivalent (A, C, W-135, Y) conjugate vaccine (MenACWY-CRM) at 6 and 12 months, one dose of MenACWY-CRM at 12 months, or MenC at 12 months and MenACWY-CRM at 18 months. Bactericidal antibody titers using human complement were measured before and 1 month after each dose. Injection-site reactions were reported by 22-45% of participants following MenACWY-CRM given at 6 or 12 months. Similar proportions of subjects had injection-site reactions following two doses of MenACWY-CRM (32-41%) or one dose of MenC (26-44%). The incidence of systemic adverse events was comparable between groups. After two doses of MenACWY-CRM, the percentages of participants reporting hSBA titers >or=8 were 100% for C, W-135, and Y, and 84% for A. Serogroup C titers were more than 10-fold higher after two doses of MenACWY-CRM than after one dose of MenC or MenACWY-CRM at 12 months. Serogroup C titers were comparable following a single dose of MenACWY-CRM or MenC at 12 months. MenACWY-CRM is well tolerated and immunogenic given at 12 months, or two doses at 6 and 12 months of age. PMID:20033465
Halperin, S A; Diaz-Mitoma, F; Dull, P; Anemona, A; Ceddia, F
Background There is limited knowledge of serotypes that cause non-bacteremic pneumococcal pneumonia (NBP). Here we report serotypes, their associated disease potential and coverage of pneumococcal conjugate vaccines (PCV) in adults with NBP and compare these to bacteremic pneumonia (BP). Methods Adults with pneumonia and Streptococcus pneumoniae isolated from the lower respiratory tract or blood were included 1 year in a population-based design in Denmark. Pneumonia was defined as a new infiltrate on chest radiograph in combination with clinical symptoms or elevated white blood count or plasma C-reactive protein. All isolates were serotyped using type-specific pneumococcal rabbit antisera. All values are medians with interquartile ranges. Results There were 272 cases of NBP and 192 cases of BP. Ninety-nine percent were hospitalized. NBP and BP cases were of comparable age and sex but NBP cases had more respiratory symptoms and less severe disease compared to BP cases. In total, 46 different serotypes were identified. Among NBP cases, 5 serotypes accounted for nearly a third of isolates. PCV10 and -13 types covered 17% (95% confidence interval (CI): 11-23%) and 34% (95% CI: 25-43%) of NBP isolates, respectively. In contrast, the five most frequent serotypes accounted for two-thirds of BP isolates. PCV10 and -13 types covered 39% (95% CI: 30-48%) and 64% (95% CI: 48-79) of BP isolates, respectively. More severe NBP disease was associated with infection with invasive serotypes while there was an inverse relationship for BP. Conclusions Only a third of cases of adult non-bacteremic pneumococcal pneumonia would potentially be preventable with the use of PCV13 and just one sixth of cases with the use of PCV10 indicating that PCVs with increased valency are needed to increase vaccine coverage for NBP in adults. PCV13 could potentially prevent two-thirds of adult bacteremic pneumococcal pneumonia.
Benfield, Thomas; Skovgaard, Marlene; Sch?nheyder, Henrik Carl; Knudsen, Jenny Dahl; Bangsborg, Jette; ?stergaard, Christian; Slotved, Hans-Christian; Konradsen, Helle Bossen; Thomsen, Reimar Wernich; Lambertsen, Lotte
Continued Haemophilus influenzae type b (Hib) carriage in rural Alaska contributes to the ongoing risk of invasive disease. Community-wide Hib carriage surveys were conducted in three villages in southwestern Alaska. Sixteen carriers and 32 age- and village-matched controls were enrolled and were vaccinated with Hib oligosaccharide-CRM(197) conjugate vaccine. Serum immunoglobulin G (IgG) concentration, antibody avidity, and serum bactericidal activity (SBA) were measured prior to Hib vaccination and 2 and 12 months after vaccination. We identified no demographic or behavioral factors associated with Hib colonization. Prior to vaccination, Hib carriers had a higher IgG geometric mean concentration than controls did (8.2 versus 1.6 microg/ml; P < 0.001) and a higher SBA geometric mean titer (7,132 versus 1,235; P = 0.006). Both groups responded to vaccination with increased IgG and SBA. These data illustrate the role of Hib colonization as an immunizing event and show that Hib carriers in communities with ongoing transmission have no evidence of reduced immune responsiveness that may have put them at risk for colonization. PMID:16760318
Baggett, Henry C; Hennessy, Thomas W; Bulkow, Lisa; Romero-Steiner, Sandra; Hurlburt, Debra; Holder, Patricia; Parkinson, Alan J; Singleton, Rosalyn J; Levine, Orin; Carlone, George M; Butler, Jay C
The antibody data supporting the use of meningococcal serogroup C conjugate (MCC) vaccines in the United Kingdom were generated by serum bactericidal assay (SBA) using rabbit complement (rSBA). This may give higher titers than those obtained with human complement (hSBA), for which the “gold standard” correlate of protection for meningococcal C disease is a titer of ?4. Comparison of rSBA and hSBA titers in sera from unvaccinated adults with an rSBA titer of ?8 showed that for 93% (27 of 29) the titer was ?4 by hSBA, confirming natural protection. Furthermore, sera from MCC vaccinees showed that an rSBA titer of <8 or ?128 discriminated susceptibility and protection well (85% with rSBA titers of <8 had hSBA titers of <4, and 99% with rSBA titers of ?128 had hSBA titers of ?4). However, discrimination was poor in the rSBA titer range 8 to 64, with only 60% having hSBA titers of ?4. In such cases we propose that protection can be assumed if there is a fourfold rise in titer between pre- and postvaccination sera or if there is a characteristic booster response to a polysaccharide challenge dose with, if available, evidence of antibody avidity maturation or an hSBA titer of result ?4. Applying these criteria to toddlers, 10 to 40% of whom had titers in the range 8 to 64 after a single dose of MCC vaccine, showed that 94% had a fourfold rise in titer, including 98% of those in the titer range 8 to 64. In addition, of those with titers of <128 post-MCC vaccination, 90% had titers of ?128 after a 10-?g polysaccharide booster dose, compared with only 7% of unprimed age-matched toddlers given a full 50-?g dose. Furthermore, the increase in geometric mean avidity index pre- and postbooster was independent of post-primary MCC titer. These results indicated that the majority of toddlers with an rSBA titer between 8 and 64, and some of those with an hSBA result of <4, have mounted a protective immune response with the induction of immunological memory.
Borrow, Ray; Andrews, Nick; Goldblatt, David; Miller, Elizabeth
Prediction of Pneumococcal Conjugate Vaccine Effectiveness against Invasive Pneumococcal Disease Using Opsonophagocytic Activity and Antibody Concentrations Determined by Enzyme-Linked Immunosorbent Assay with 22F Adsorption ?
We compared the abilities of two serological readouts, antipolysaccharide IgG antibody concentrations and opsonophagocytic activity (OPA) titers, to predict the clinical effectiveness of the 7-valent pneumococcal conjugate vaccine (7vCRM) against invasive pneumococcal disease (IPD). We also assessed the accuracy of the previously established thresholds for GlaxoSmithKline's enzyme-linked immunosorbent assay with 22F adsorption (22F-ELISA) (?0.2 ?g/ml) and OPA assay (titer, ?8) in predicting effectiveness. We showed that following a 3-dose 7vCRM primary vaccination, the serological response rates as determined using thresholds of ?0.2 ?g/ml IgG and an OPA titer of ?8 corresponded well with overall effectiveness against IPD. In addition, the OPA assay seemed to better predict serotype-specific effectiveness than enzyme-linked immunoassay. Finally, when applied to post-dose-2 immune responses, both thresholds also corresponded well with the overall IPD effectiveness following a 2-dose 7vCRM primary vaccination. These results support the importance of the OPA assay in evaluating immune responses to pneumococcal conjugate vaccines.
Schuerman, L.; Wysocki, J.; Tejedor, J. C.; Knuf, M.; Kim, K.-H.; Poolman, J.
The Magnitude of the Antibody and Memory B Cell Responses during Priming with a Protein-Polysaccharide Conjugate Vaccine in Human Infants Is Associated with the Persistence of Antibody and the Intensity of Booster Response1
Rapid waning of anti-polysaccharide bactericidal Ab and vaccine effectiveness is observed following infant immunization with the serogroup C meningococcal (MenC) glycoconjugate vaccine. This is despite the demonstrable presence of immunological memory. Persistence of functional Ab, therefore, appears to be the key determinant of MenC conjugate vaccine effectiveness. Ab persistence is thought to depend in the short term on the survival
Geraldine Blanchard Rohner; Matthew D. Snape; Dominic F. Kelly; Tessa John; Anita Morant; Ly-Mee Yu; Astrid Borkowski; Francesca Ceddia; Ray Borrow; Claire-Anne Siegrist; Andrew J. Pollard
Outbred NMRI mice and rabbits were vaccinated with different artificial Salmonella typhimurium immunogens and the specificity and activity of elicited antibodies were studied in in vivo and in vitro phagocytosis assays. The Salmonella immunogens used were: (i) the synthetic disaccharide, abequose (formula see text) D-mannose, representative of Salmonella O antigen 4, covalently linked to bovine serum albumin (BSA); (ii) the octa- and dodecasaccharides, (formula see text) covalently linked to BSA; and (iii) whole heat-killed Salmonella. Rabbit antibodies passively administered to mice significantly enhanced the clearance of intravenously injected S. typhimurium challenge bacteria from the bloodstream. The clearance rate and the titer of anti-O-antigen-specific antibodies correlated. The clearance rate of an S. thompson (O6,7) strain, which has a different O antigen, was the same irrespective of the rabbit serum given. NMRI mice actively immunized with the various oligosaccharide-BSA conjugates had a significantly increased clearance rate of S. typhimurium only. In the in vitro assay, mouse antioligosaccharide-BSA sera promoted phagocytosis of S. typhimurium, but not S. thompson, when incubated with complement and mouse peritoneal exudate cells activated with Freund complete adjuvant.
Jorbeck, H J; Svenson, S B; Lindberg, A A
Pneumococcal conjugate vaccines (PCVs) were licensed for use in children and became available for private purchase in Spain in 2001 (PCV7), 2009 (PCV10) and 2010 (PCV13). This study evaluates changes in the incidence of invasive pneumococcal disease (IPD) and the pattern of serotypes isolated in Navarre, Spain, between the period of use of PCV7 (2004-2009) and that of PCV13 (2010-2013). The percentage of children <2 years who received at least one dose of PCV in these periods ranged from 25 to 61% and 61 to 78%, respectively. Between the periods 2004-2009 and 2010-2013 IPD incidence declined by 37%, from 14.9 to 9.4 cases/100,000 inhabitants (p<0.001). In children <5 years it fell by 69% (p<0.001), in persons aged 5-64 years, by 34% (p<0.001), and in those ? 65, by 23% (p=0.024). The incidence of cases due to PCV13 serotypes declined by 81% (p<0.001) in children <5 years and by 52% (p<0.001) in the whole population. No significant changes were seen in the distribution of clinical presentations or in disease severity. The incidence of IPD has declined and the pattern of serotypes causing IPD has changed notably in children and moderately in adults following the replacement of PCV7 by PCV13. PMID:24674661
Guevara, Marcela; Ezpeleta, Carmen; Gil-Setas, Alberto; Torroba, Luis; Beristain, Xabier; Aguinaga, Aitziber; García-Irure, José Javier; Navascués, Ana; García-Cenoz, Manuel; Castilla, Jesús
The response to booster vaccination at 15-18 months of age and the presence of immune memory in 10-month old children, primed with a new combined diphtheria-tetanus-hepatitis B-whole cell pertussis vaccine extemporaneously mixed with Haemophilus influenzae type b-tetanus toxoid conjugate (DTPw-HBV/Hib) from new antigen sources and containing 2.5 microg polyribosyl-ribitol-phosphate (PRP) was assessed. Primary vaccination with the new DTPw-HBV/Hib vaccine was immunogenic and of comparable tolerability to commercially available Tritanrix HepB/Hiberix. Children were boosted with DTPw-HBV, DTPw-HBV/Hib or separate DTPw-HBV+Hiberix. Immune memory was assessed through administration of 10 microg PRP polysaccharide. Anti-PRP antibody GMCs increased substantially after the challenge in DTPw-HBV/Hib-primed subjects indicating the presence of immune memory. One month after the booster dose, 100% of subjects had seroprotective antibody concentrations against PRP, diphtheria and tetanus, >95% were seroprotected against hepatitis B, > or =94.0% had a pertussis booster response. Substantial increases in antibody GMCs against all antigens were observed. Swelling >20 mm was the most common Grade 3 solicited symptom reported (up to 26.0% of subjects). Fever >39.5 degrees C was uncommon (>2.5%). Eleven large swelling reactions were reported; none involved an adjacent joint. One serious adverse event occurred that was considered unrelated to vaccination. This new DTPw-HBV/Hib vaccine with new vaccine components and 2.5 microg PRP induced effective priming against Hib evidenced by a vigorous anamnestic response on exposure to PRP polysaccharide. The booster dose was immunogenic and the safety profile was acceptable. Combined DTPw-HBV and DTPw-HBV/Hib vaccines using new vaccine antigen sources will promote continued supply of combined DTPw-based vaccines to global mass vaccination campaigns. PMID:18376148
Gatchalian, Salvacion; Reyes, Marietta; Bermal, Nancy; Chandrasekaran, Vijayalakshmi; Han, Htay Htay; Bock, Hans L; Lefevre, Inge
Antigenicities of several formalin-detoxified botulinum neurotoxin preparations were measured by inhibition and sandwich enzyme-linked immunosorbent assay (ELISA), and immunogenicity was studied in mice. The toxoids were derived primarily from the serotype A 150-kDa neurotoxin protein, while one toxoid was derived from the naturally occurring 900-kDa toxin-hemagglutinin complex. Antigenicity was severely compromised in two commercially available toxoids. A variety of new toxoids were synthesized in-house by optimizing formaldehyde reaction conditions. Three of the resulting toxoids were found to be antigenically identical to the native toxin, as measured by inhibition ELISA, in spite of showing a reduction of toxicity by more than 100,000-fold. Sandwich ELISAs indicated that the in-house toxoids were two- to threefold less antigenic than the neurotoxin compared to commercial toxoids, which were about 100-fold less antigenic. Mice were immunized twice, on day 0 and day 14. By day 28, relatively high toxin-specific immunoglobulin G (IgG) titers were detected in animals that had received any of the in-house toxoids, with greater than 99% being IgG1 and the remainder being IgG2. These immunized mice remained asymptomatic after being challenged with 50 to 1,000,000 50% lethal dose (LD(50)) units of the 900-kDa neurotoxin. In contrast, animals immunized with several different batches of commercially available toxoids did not develop measurable toxin-specific antibody titers. However, these mice survived neurotoxin challenges with 2 LD(50) units but died when challenged with 6 LD(50) units. Neutralizing titers measured from pools of sera generated with the in-house toxoid preparations ranged from 2.5 to 5 U/ml. In terms of predicting immunogenicity, inhibition ELISAs comparing each formalin toxoid to the parent toxin provided good insight for screening the new toxoids as well as for estimating their relative in vivo potencies. Inhibition ELISA data indicate that those toxoids that most closely resemble the native toxin are highly immunogenic and protective. The superior quality of these new toxoids makes them useful tools for continued use in ELISA development and for antitoxin production. PMID:18667637
Keller, James E
Pneumococcal disease epidemiology has changed after introduction of pneumococcal conjugate vaccines. Seven-valent vaccine (PCV7) has been effective in reducing invasive pneumococcal disease (IPD). In Europe, PCV13 effectiveness was estimated at 78% (95% CI: -18-96%) for 2-priming doses. In Italy, PCV7 was introduced in 2006 in the childhood immunization schedule and replaced with PCV13 in 2010. In Apulia, vaccination coverage has reached 95.1% (birth-cohort 2010). We estimated PCV program effectiveness and its impact on S. pneumoniae diseases. PCV Effectiveness: We used the screening method. We calculated the Proportion of Population Vaccinated from immunization registries and detected cases through a laboratory-confirmed surveillance among hospitalized children ?60 months. A confirmed IPD case was a child with PCR positive for S. pneumoniae. Differences among children were assessed with the Chi-square or the Fisher exact test (P value<0.05). PCV Impact: We constructed time series using outcome-specific Poisson regression models: hospitalization rate in pre-PCV era and hospitalization risk ratios (RRs) with 95% CIs for both PCV7 and PCV7/PCV13 shifting era. We calculated hospitalization RR with 95% CIs comparing pre-PCV years with vaccination period. The PCV effectiveness was 84.3% (95% CI: 84.0-84.6%). In May 2010-January 2013, we enrolled 159 suspected IPD of whom 4 were confirmed. Two (fully vaccinated) were caused by serotype 9V, 1 (not vaccinated) by serotype 3, 1 (vaccinated with 2 PCV13 doses) by 15B/C. The most important reduction was for pneumococcal pneumonia (RR: 0.43, 95% CI: 0.21-0.90). The PCV program show promising results in terms of both PCV13 effectiveness and its impact in reducing IPD in children<5 years. PMID:24096297
Martinelli, Domenico; Pedalino, Biagio; Cappelli, Maria Giovanna; Caputi, Giovanni; Sallustio, Anna; Fortunato, Francesca; Tafuri, Silvio; Cozza, Vanessa; Germinario, Cinzia; Chironna, Maria; Prato, Rosa; Surveillance Of Pediatric Ipd, Apulian Group For The
The acylated form of protein D of Haemophilus influenzae is more immunogenic than the nonacylated form and elicits an adjuvant effect when it is used as a carrier conjugated to polyribosyl ribitol phosphate.
The nonacylated form of protein D (PDm) of Haemophilus influenzae has been shown to induce the production of antibodies that are bactericidal to homologous and heterologous nontypeable H. influenzae (NTHi) strains. In this study, immunization of rats with lipoprotein D (LPD) induced higher levels of anti-protein D immunoglobulin G and A serum antibodies than immunization with PDm, and the bactericidal activities of sera from LPD-immunized rats were greater than those of sera from PDm-immunized rats. Immunization with LPD or PDm did not prevent the development of acute otitis media (AOM) when rats were challenged with 10(4) CFU of an NTHi strain. However, on the eighth day of bacterial challenge, 50% (5 of 10) of LPD-immunized rats had recovered from otitis media and 30% (3 of 10) had negative middle ear cultures, whereas only 30% (3 of 10) of PDm-immunized rats had recovered, though none was culture positive. Immunization with an inactivated homologous bacterial strain elicited 70% protection (i.e., 7 of 10 rats) in the rat otitis media model. LPD and PDm were also conjugated to the H. influenzae type b (Hib) capsular polysaccharide, polyribosyl ribitol phosphate (PRP), to test protein D-conjugated PRP vaccine's potential for protection against Hib infection. When two LPD-conjugated and two PDm-conjugated PRP vaccines, each containing a different protein concentration, and a tetanus toxoid-conjugated vaccine (ACT-HIB) were tested in the experimental model of rat otitis induced with a Hib strain (Minn A), both of the LPD-conjugated and one of the PDm-conjugated vaccines induced significant protection from AOM, the level of protection being highest in animals given the vaccine with the highest LPD content. Sera from these rats also manifested the highest anti-PRP and anti-LPD antibody levels and the highest bactericidal activities against a Hib strain and an NTHi strain.
Akkoyunlu, M; Melhus, A; Capiau, C; van Opstal, O; Forsgren, A
Toxin from Clostridium botulinum type F was recovered from dialysis cultures and partially purifed by: (i) ammonium sulfate and ethanol precipitation; (ii) O-(diethylaminoethyl)-cellulose chromatography; or (iii) diethylaminoethyl-cellulose chromatography followed by O-(carboxymethyl)-cellulose chromatography. Toxin purities as reflected by specific activity were 1.83 X 10(6), 9.8 X 10(6), and 2.0 X 10(7) mouse 50% lethal doses (LD50)/mg of N, respectively, for toxins purified by the three methods. The toxins were converted to toxoids by incubation at 35 C in the presence of 0.3 to 0.45% formalin for 21 to 35 days. Toxoids were immunogenic in guinea pigs, as demonstrated by serum antitoxin response and the immunized animals' resistance to challenge by type F botulinal toxin. The immune response to type F toxoids was lower when toxoids of serotypes A, B, C, D, and E were combined with the type F toxoid than when the type F toxoid only was administered. The toxoid prepared from the most highly purified toxin (method [iii]) conferred the highest immunity in guinea pigs at a given dose level. A relation between serum antitoxin level and resistance to challenge was observed. At least 50% of the groups of guinea pigs with 0.015 antitoxin units or more per ml survived challenge by 10(5) mouse LD50 of type F botulinal toxin. A dose of 3.75 mug of N of the most highly purified type F toxoid in combination with the other five serotypes of botulinal toxoid invoked an immune response in guinea pigs comparable to that considered adequate for the other toxoids.
Hatheway, C L
Polypeptide and DNA vaccine alternatives to the conventional tetanus toxoid were compared. Mouse immunizations with plasmid DNA that encoded the tetanus toxin C fragment polypeptide induced consistently lower antibody responses than direct immunization with the C fragment polypeptide or toxoid, yet provided some degree of protection from a lethal toxin challenge. Cytotoxic T-cell responses dominated DNA immunizations, while specific T-cell
Kamal U. Saikh; Julie Sesno; Patricia Brandler; Robert G. Ulrich
Introduction Data on the prevalence of nasopharyngeal carriage of S.pneumoniae in all age groups are important to help predict the impact of introducing pneumococcal conjugate vaccines (PCV) into routine infant immunization, given the important indirect effect of the vaccine. Yet most carriage studies are limited to children under five years of age. We here explore the association between carriage prevalence and serotype distribution in children aged ?5 years and in adults compared to children. Methods We conducted a systematic review of studies providing carriage estimates across age groups in healthy populations not previously exposed to PCV, using MEDLINE and Embase. We used Bayesian linear meta-regression models to predict the overall carriage prevalence as well as the prevalence and distribution of vaccine and nonvaccine type (VT and NVT) serotypes in older age groups as a function of that in <5 y olds. Results Twenty-nine studies compromising of 20,391 individuals were included in the analysis. In all studies nasopharyngeal carriage decreased with increasing age. We found a strong positive linear association between the carriage prevalence in pre-school childen (<5 y) and both that in school aged children (5–17 y olds) and in adults. The proportion of VT serotypes isolated from carriers was consistently lower in older age groups and on average about 73% that of children <5 y among 5–17 y olds and adults respectively. We provide a prediction model to infer the carriage prevalence and serotype distribution in 5–17 y olds and adults as a function of that in children <5 years of age. Conclusion Such predictions are helpful for assessing the potential population-wide effects of vaccination programmes, e.g. via transmission models, and thus assist in the design of future pneumococcal conjugate vaccination strategies.
Le Polain de Waroux, Olivier; Flasche, Stefan; Prieto-Merino, David; Edmunds, W. John
Background Approximately 826,000 children, mostly young infants, die annually from invasive pneumococcal disease. A 6-10-14-week schedule of pneumococcal conjugate vaccine (PCV) is efficacious but neonatal PCV may provide earlier protection and better coverage. We conducted an open randomized controlled trial in Papua New Guinea to compare safety, immunogenicity and priming for memory of 7-valent PCV (PCV7) given in a 0-1-2-month (neonatal) schedule with that of the routine 1-2-3-month (infant) schedule. Methods We randomized 318 infants at birth to receive PCV7 in the neonatal or infant schedule or no PCV7. All infants received 23-valent pneumococcal polysaccharide vaccine (PPV) at age 9 months. Serotype-specific serum IgG for PCV7 (VT) serotypes and non-VT serotypes 2, 5 and 7F were measured at birth and 2, 3, 4, 9, 10 and 18 months of age. Primary outcomes were geometric mean concentrations (GMCs) and proportions with concentration ?0.35 µg/ml of VT serotype-specific pneumococcal IgG at age 2 months and one month post-PPV. Results We enrolled 101, 105 and 106 infants, respectively, into neonatal, infant and control groups. Despite high background levels of maternally derived antibody, both PCV7 groups had higher GMCs than controls at age 2 months for serotypes 4 (p<0.001) and 9V (p<0.05) and at age 3 months for all VTs except 6B. GMCs for serotypes 4, 9V, 18C and 19F were significantly higher (p<0.001) at age 2 months in the neonatal (one month post-dose2 PCV7) than in the infant group (one month post-dose1 PCV7). PPV induced significantly higher VT antibody responses in PCV7-primed than unprimed infants, with neonatal and infant groups equivalent. High VT and non-VT antibody concentrations generally persisted to age 18 months. Conclusions PCV7 is well-tolerated and immunogenic in PNG neonates and young infants and induces immunologic memory to PPV booster at age 9 months with antibody levels maintained to age 18 months. Trial Registration ClinicalTrials.gov NCT00219401NCT00219401
Phuanukoonnon, Suparat; Francis, Jacinta; Jacoby, Peter; Siba, Peter M.; Alpers, Michael P.; Reeder, John C.; Holt, Patrick G.; Richmond, Peter C.; Lehmann, Deborah
Streptococcal mitogenic exotoxin Z-2 (SMEZ-2) is a streptococcal superantigen that primarily stimulates human T cells bearing V?8 and mouse T cells bearing V?11. Mutagenesis of T cell receptor (TCR)-binding residues (W75L, K182Q, D42C) produced a mutant called M1 that was >105-fold less active toward human peripheral blood lymphocytes and splenocytes from transgenic mice that express human CD4 and either human HLA-DR3-DQ2 or HLA-DR4-DQ8. Similarly, cytokine production in response to M1 in lymphocyte culture was rendered undetectable, and no change in the frequency of V?11-bearing T cells in mice receiving M1 was observed. M1 toxoid was tested as a potential vaccine conjugate. Vaccination with 1 to 10 ?g M1 conjugated to ovalbumin (M1-ovalbumin) resulted in more rapid and quantitatively higher levels of anti-ovalbumin IgG, with endpoint titers being 1,000- to 10,000-fold greater than those in animals immunized with unconjugated ovalbumin. Substantially higher levels of anti-ovalbumin IgG were observed in mice transgenic for human major histocompatibility complex (MHC) class II. Substitution of M1 with an MHC class II binding mutant (DM) eliminated enhanced immunity, suggesting that M1 enhanced the delivery of antigen via MHC class II-positive antigen-presenting cells that predominate within lymphoid tissue. Immunization of animals with a conjugate consisting of M1 and ovalbumin peptide from positions 323 to 339 generated levels of anti-peptide IgG 100-fold higher than those in animals immunized with peptide alone. Coupling of a TCR-defective superantigen toxoid presents a new strategy for conjugate vaccines with the additional benefit of targeted delivery to MHC class II-bearing cells.
Radcliff, Fiona J.; Loh, Jacelyn M. S.; Ha, Birgit; Schuhbauer, Diana; McCluskey, James
Streptococcal mitogenic exotoxin Z-2 (SMEZ-2) is a streptococcal superantigen that primarily stimulates human T cells bearing V?8 and mouse T cells bearing V?11. Mutagenesis of T cell receptor (TCR)-binding residues (W75L, K182Q, D42C) produced a mutant called M1 that was >10(5)-fold less active toward human peripheral blood lymphocytes and splenocytes from transgenic mice that express human CD4 and either human HLA-DR3-DQ2 or HLA-DR4-DQ8. Similarly, cytokine production in response to M1 in lymphocyte culture was rendered undetectable, and no change in the frequency of V?11-bearing T cells in mice receiving M1 was observed. M1 toxoid was tested as a potential vaccine conjugate. Vaccination with 1 to 10 ?g M1 conjugated to ovalbumin (M1-ovalbumin) resulted in more rapid and quantitatively higher levels of anti-ovalbumin IgG, with endpoint titers being 1,000- to 10,000-fold greater than those in animals immunized with unconjugated ovalbumin. Substantially higher levels of anti-ovalbumin IgG were observed in mice transgenic for human major histocompatibility complex (MHC) class II. Substitution of M1 with an MHC class II binding mutant (DM) eliminated enhanced immunity, suggesting that M1 enhanced the delivery of antigen via MHC class II-positive antigen-presenting cells that predominate within lymphoid tissue. Immunization of animals with a conjugate consisting of M1 and ovalbumin peptide from positions 323 to 339 generated levels of anti-peptide IgG 100-fold higher than those in animals immunized with peptide alone. Coupling of a TCR-defective superantigen toxoid presents a new strategy for conjugate vaccines with the additional benefit of targeted delivery to MHC class II-bearing cells. PMID:22301693
Radcliff, Fiona J; Loh, Jacelyn M S; Ha, Birgit; Schuhbauer, Diana; McCluskey, James; Fraser, John D
Randomized Trial on the Safety, Tolerability, and Immunogenicity of MenACWY-CRM, an Investigational Quadrivalent Meningococcal Glycoconjugate Vaccine, Administered Concomitantly with a Combined Tetanus, Reduced Diphtheria, and Acellular Pertussis Vaccine in Adolescents and Young Adults? †
This study evaluated the safety, tolerability, and immunogenicity of an investigational quadrivalent meningococcal conjugate vaccine, MenACWY-CRM, when administered concomitantly with a combined tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine, in subjects aged 11 to 25 years. Subjects received either MenACWY-CRM and Tdap, MenACWY-CRM and saline placebo, or Tdap and saline placebo. No significant increase in reactogenicity and no clinically significant vaccine-related adverse events (AEs) occurred when MenACWY-CRM and Tdap were administered concomitantly. Similar immunogenic responses to diphtheria, tetanus, and meningococcal (serogroups A, C, W-135, and Y) antigens were observed, regardless of concomitant vaccine administration. Antipertussis antibody responses were comparable between vaccine groups for filamentous hemagglutinin and were slightly lower, although not clinically significantly, for pertussis toxoid and pertactin when the two vaccines were administered concomitantly. These results indicate that the investigational MenACWY-CRM vaccine is well tolerated and immunogenic and that it can be coadministered with Tdap to adolescents and young adults.
Gasparini, Roberto; Conversano, Michele; Bona, Gianni; Gabutti, Giovanni; Anemona, Alessandra; Dull, Peter M.; Ceddia, Francesca
Randomized trial on the safety, tolerability, and immunogenicity of MenACWY-CRM, an investigational quadrivalent meningococcal glycoconjugate vaccine, administered concomitantly with a combined tetanus, reduced diphtheria, and acellular pertussis vaccine in adolescents and young adults.
This study evaluated the safety, tolerability, and immunogenicity of an investigational quadrivalent meningococcal conjugate vaccine, MenACWY-CRM, when administered concomitantly with a combined tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine, in subjects aged 11 to 25 years. Subjects received either MenACWY-CRM and Tdap, MenACWY-CRM and saline placebo, or Tdap and saline placebo. No significant increase in reactogenicity and no clinically significant vaccine-related adverse events (AEs) occurred when MenACWY-CRM and Tdap were administered concomitantly. Similar immunogenic responses to diphtheria, tetanus, and meningococcal (serogroups A, C, W-135, and Y) antigens were observed, regardless of concomitant vaccine administration. Antipertussis antibody responses were comparable between vaccine groups for filamentous hemagglutinin and were slightly lower, although not clinically significantly, for pertussis toxoid and pertactin when the two vaccines were administered concomitantly. These results indicate that the investigational MenACWY-CRM vaccine is well tolerated and immunogenic and that it can be coadministered with Tdap to adolescents and young adults. PMID:20164251
Gasparini, Roberto; Conversano, Michele; Bona, Gianni; Gabutti, Giovanni; Anemona, Alessandra; Dull, Peter M; Ceddia, Francesca
Serogroup B Neisseria meningitidis (MenB) is a major cause of invasive disease in early childhood worldwide. The only MenB vaccine available in Brazil was produced in Cuba and has shown unsatisfactory efficacy when used to immunize millions of children in Brazil. In the present study, we compared the specific functional antibody responses evoked by the Cuban MenB vaccine with a standard vaccine against diphtheria (DTP: diphtheria, tetanus, pertussis) after primary immunization and boosting of mice. The peak of bactericidal and opsonic antibody titers to MenB and of neutralizing antibodies to diphtheria toxoid (DT) was reached after triple immunization with the MenB vaccine or DTP vaccine, respectively. However, 4 months after immunization, protective DT antibody levels were present in all DTP-vaccinated mice but in only 20% of the mice immunized against MenB. After 6 months of primary immunization, about 70% of animals still had protective neutralizing DT antibodies, but none had significant bactericidal antibodies to MenB. The booster doses of DTP or MenB vaccines produced a significant antibody recall response, suggesting that both vaccines were able to generate and maintain memory B cells during the period studied (6 months post-triple immunization). Therefore, due to the short duration of serological memory induced by the MenB vaccine (VA-MENGOC-BC® vaccine), its use should be restricted to outbreaks of meningococcal disease.
Silva, G.P.; Cruz, S.C.; Cruz, A.C.; Milagres, L.G.
Background Protection against disease or colonization from serotypes related to those in pneumococcal conjugate vaccines (i.e. cross-protection) vary by serotype; the basis for this variation is not understood. The 13-valent pneumococcal conjugate vaccine (PCV13) replaced 7-valent conjugate (PCV7) in the USA in 2010 allowing assessment of PCV7 and PCV13 immunogenicity and functional cross-protection in vitro. Methods Post-primary, pre-booster and post-booster sera from American Indian children receiving exclusively PCV7 or PCV13 were collected. IgG was measured by ELISA for 13 vaccine serotypes; functional antibody was assessed by opsonophagocytic killing assays for serotypes 6A/B/C and 19A/F. Results Post-primary IgG geometric mean concentrations (GMC) for serotypes 4 and 9V were lower in PCV13 recipients while 19F GMCs were higher. Only 19F differences persisted after receipt of the booster dose. Functional antibody activity was higher among PCV13 recipients for 6A, 6C, 19A and 19F (p<0.04), and among PCV7 recipients for 6B (p?=?0.01). Following PCV7, functional antibodies to 6A but not 19A were observed. High levels of 6C functional activity were seen after PCV13 but not PCV7. Conclusions Functional antibody activity against 6A/B/C and 19A/F suggest that PCV13 is likely to control the 19A disease and 6C disease remaining despite widespread use of PCV7.
Grant, Lindsay R.; O'Brien, Sarah E.; Burbidge, Polly; Haston, Mitch; Zancolli, Marta; Cowell, Lucy; Johnson, Marina; Weatherholtz, Robert C.; Reid, Raymond; Santosham, Mathuram; O'Brien, Katherine L.; Goldblatt, David
This study describes the serotype distribution and antibiotic resistance patterns among 397 S. pneumoniae meningitis case isolates recovered in Salvador, Brazil, during the period of 2000-2007, before introduction of the 10-valent pneumococcal conjugate vaccine. The active hospital-based surveillance showed a decline in the annual incidence rates of pneumococcal meningitis during the period of study, from 1.12 cases to 0.83 cases/100,000 persons for all age groups (P <0.001), with an overall case-fatality rate of 28.6 % (113 of 395) for all patients and 41.9% (57 of 136) for those <5 years of age. Serotypes 14 (n= 55; 13.9%), 3 (n= 32; 8.1 %), 23F (n=32; 8.1 %), 19F (n=31; 7.8%), 6B (n=30; 7.6%), 18C (n=28; 7.1 %), and 6A (n=20; 5%) were the most prevalent serotypes. In patients < 5 years the estimated projected coverage of 7-, 10- and 13-valent conjugate vaccines was 74.3%, 75.7% and 83.1%, respectively. Antimicrobial susceptibility testing revealed that 22.1% (n=88) of isolates were non-susceptible to penicillin, 56% were non-susceptible to trimethoprim/sulfamethoxazole, and 29.6% were non-susceptible to tetracycline. Nonsusceptibility to penicillin and cefotaxime was detected solely among serotype 14 isolates (n=4; 1%). This study provides an important baseline to assess the impact of conjugate vaccine implantation on the epidemiology of meningitis due to Streptococcus pneumoniae in Salvador, Brazil.
Menezes, Ana Paula de O.; Campos, Leila C.; dos Santos, Milena S.; Azevedo, Jailton; dos Santos, Renan Cardoso Nery; Carvalho, Maria da Gloria S.; Beall, Bernard W.; Martin, Stacey W.; Salgado, Katia; Reis, Mitermayer G.; Ko, Albert I.; Reis, Joice N.
We have prepared polysaccharide-protein conjugates consisting of type 4 pneumococcal capsular polysaccharide (PS4) coupled to tetanus toxoid. The PS4 preparation used contained 2.5% pneumococcal cell wall polysaccharide (CPs). During the conjugation process, in addition to PS4-protein conjugates, CPs-protein conjugates were also formed. After immunization with PS4-protein conjugates, CPs-protein conjugates that are present as a contaminant induce IgG anti-CPs antibodies in
Carla Peeters; Anne-Marie Tenbergen-Meekes; Jan Poolmann; Ben Zegers; Ger Rijkers
Background Recommendations for diphtheria immunization are to apply an effective primary immunization in infancy and to maintain immunity throughout life. Immunity against diphtheria depends primarily on antibody to the diphtheria toxin. This study evaluated the seroprevalence of IgG diphtheria antitoxin in sera of healthy children, adolescents and adults in Poland. Methods A total of 1387 serum samples collected between 2010 and 2012 from individuals with ages ranging from 1 month to 85 years were investigated. Antibody concentrations were measured with an enzyme-linked immunosorbent assay (Anti-Diphtheria Toxoid ELISA IgG, Euroimmun, Germany). Results The results showed that among 1387 individuals examined, 547 (39.4%) had anti-diphtheria toxoid IgG antibody levels below 0.1 IU/ml (36.9% ?18 years and 40.5% >18 years old, respectively). The 212 (50.8%) children and 542 (55.9%) adults showed only basic protection (0.1-1.0 IU/ml) and need immediate booster. High levels of anti-diphtheria toxoid IgG antibodies (>1.0 IU/ml) were found more often in children and adolescent (12.2%) than in adults (3.6%) and this was statistically significant (P?0.05). The proportion of seronegatives (0.1 IU/ml) in children below 2 years old, adolescents and young adults to 25 years old decreased from 53.5% to 17.4%. However, in older individuals the seronegative proportion tended to increase with age, from 22.7% in adults (26–30 years old) to 67.1% in subjects?>?60 years old. Characteristically, in individuals >?40 years old high levels of anti-diphtheria toxoid IgG antibodies (>1.0 IU/ml) were not seen. There were no statistically significant differences in results in relation to gender. Conclusions The present study showed inadequate immunity levels to diphtheria amongst the Polish population, especially in adults >?40 years old and children ??2 years old. To prevent reemergence of diphtheria an information campaign reminding people about recommendations concerning diphtheria booster vaccination in adults should be conducted. Moreover, the immunogenicity of the DTP vaccine used in Poland should be verified.
The ten-pneumococcal conjugate vaccine (PCV10) was introduced into the national immunization program for childhood vaccination schedules by the Brazilian Health Public Service in March 2010. The aim of this study was to compare Streptococcus pneumoniae serotype distribution, antibiotic resistance patterns, and potential coverage before (January 2006-June 2010) and after (July 2010-September 2012) PCV10 introduction. The incidence of invasive pneumococcal disease (IPD), patient demographics, and disease characteristics were recorded. This study was conducted at the University Hospital of Sao Paulo University in Brazil from January 2006 to September 2012. Serotyping was performed using multiplex PCR typing, and antimicrobial sensitivity by Clinical and Laboratory Standards Institute (CLSI). A total of 259 S. pneumoniae strains were isolated from patients with IPD. The ages of the patients ranged from 3 months to 95 years old. The strains were isolated from cerebrospinal fluid, pleural fluid, and blood. The incidence of IPD among patients at HU-USP changed after the introduction of PCV10. The overall incidence of IPD was 3.42 cases per 1000 admissions in the vaccine pre- implementation period and of 2.99 cases per 1000 admissions in the vaccine post-implementation period. The incidence of IPD among children<2 y.o. attended at HU-USP changed significantly after the introduction of PCV10, from 20.30 to 3.97 of incidence. The incidence of PCV10- serotypes decrease from 16.47 to 0.44 in the same age, before and after PC10 implementation, respectively. Moreover, it was possible to realize the sensitivity to penicillin among isolates increased significantly in the post-vaccine period. Data from this study suggest that PCV10 contributed to decrease with PID rate among children less than 2 y.o. The resistance rate among pneumococcal isolates also could be observed since serotypes with greater resistance to beta lactam antibiotics were not easily isolated after vaccination. PMID:23747454
dos Santos, Silvia R; Passadore, Lilian F; Takagi, Elizabeth H; Fujii, Cristiane M; Yoshioka, Cristina R M; Gilio, Alfredo E; Martinez, Marina B
Streptococcus pneumoniae is a leading cause of severe infectious diseases worldwide. This paper presents the results from the first European invasive pneumococcal disease (IPD) enhanced surveillance where additional and valuable data were reported and analysed. Following its authorisation in Europe in 2001 for use in children aged between two months and five years, the heptavalent pneumococcal conjugate vaccine (PCV7) was progressively introduced in the European Union (EU)/European Economic Area (EEA) countries, albeit with different schemes and policies. In mid-2010 European countries started to switch to a higher valency vaccine (PCV10/PCV13), still without a significant impact by the time of this surveillance. Therefore, this surveillance provides an overview of baseline data from the transition period between the introduction of PCV7 and the implementation of PCV10/PCV13. In 2010, 26 EU/EEA countries reported 21 565 cases of IPD to The European Surveillance System (TESSy) applying the EU 2008 case definition. Serotype was determined in 9946/21565 (46.1%) cases. The most common serotypes were 19A, 1, 7F, 3, 14, 22F, 8, 4, 12F and 19F, accounting for 5949/9946 (59.8%) of the serotyped isolates. Data on antimicrobial susceptibility testing (AST) in the form of minimum inhibitory concentrations (MIC) were submitted for penicillin 5384/21565 (25.0%), erythromycin 4031/21565 (18.7%) and cefotaxime 5252/21565 (24.4%). Non-susceptibility to erythromycin was highest at 17.6% followed by penicillin at 8.9%. PCV7 serotype coverage among children <5 years in Europe, was 19.2%; for the same age group, the serotype coverage for PCV10 and PCV13 were 46.1% and 73.1%, respectively. In the era of pneumococcal conjugate vaccines, the monitoring of changing trends in antimicrobial resistance and serotype distribution are essential in assessing the impact of vaccines and antibiotic use control programmes across European countries. PMID:24795228
Torné, Adoración Navarro; Dias, Joana Gomes; Quinten, Chantal; Hruba, Frantiska; Busana, Marta Cecilia; Lopalco, Pier Luigi; Gauci, Andrew J Amato; Pastore-Celentano, Lucia
Epidemiologic and experimental data provide evidence that a critical level of serum immunoglobulin G (IgG) antibodies to the surface polysaccharide of Vibrio cholerae O1 (lipopolysaccharide) and of Vibrio cholerae O139 (capsular polysaccharide [CPS]) is associated with immunity to the homologous pathogen. The immunogenicity of polysaccharides, especially in infants, may be enhanced by their covalent attachment to proteins (conjugates). Two synthetic schemes, involving 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) as activating agents, were adapted to prepare four conjugates of V. cholerae O139 CPS with the recombinant diphtheria toxin mutant, CRMH21G. Adipic acid dihydrazide was used as a linker. When injected subcutaneously into young outbred mice by a clinically relevant dose and schedule, these conjugates elicited serum CPS antibodies of the IgG and IgM classes with vibriocidal activity to strains of capsulated V. cholerae O139. Treatment of these sera with 2-mercaptoethanol (2-ME) reduced, but did not eliminate, their vibriocidal activity. These results indicate that the conjugates elicited IgG with vibriocidal activity. Conjugates also elicited high levels of serum diphtheria toxin IgG. Convalescent sera from 20 cholera patients infected with V. cholerae O139 had vibriocidal titers ranging from 100 to 3,200: absorption with the CPS reduced the vibriocidal titer of all sera to < or =50. Treatment with 2-ME reduced the titers of 17 of 20 patients to < or =50. These data show that, like infection with V. cholerae O1, infection with V. cholerae O139 induces vibriocidal antibodies specific to the surface polysaccharide of this bacterium (CPS) that are mostly of IgM class. Based on these data, clinical trials with the V. cholerae O139 CPS conjugates with recombinant diphtheria toxin are planned. PMID:10948122
Kossaczka, Z; Shiloach, J; Johnson, V; Taylor, D N; Finkelstein, R A; Robbins, J B; Szu, S C
Nontypeable Haemophilus influenzae (NTHi) outer membrane protein P6 was used as a new protein carrier for NTHi detoxified lipooligosaccharide (dLOS) conjugates due to its conservation and potential to elicit bactericidal antibodies. P6 was covalently conjugated to dLOS of strain 9274 through adipic acid dihydrazide with different ratios of dLOS to P6, which resulted in two conjugate formulations with weight ratios
Tinghuai Wu; Jing Chen; Timothy F. Murphy; Bruce A. Green; Xin-Xing Gu
Epidemiologic and experimental data provide evidence that a critical level of serum immunoglobulin G (IgG) antibodies to the surface polysaccharide of Vibrio cholerae O1 (lipopolysaccharide) and of Vibrio cholerae O139 (capsular polysaccharide (CPS)) is associated with immunity to the homologous pathogen. The immunoge- nicity of polysaccharides, especially in infants, may be enhanced by their covalent attachment to proteins (conjugates). Two
ZUZANA KOSSACZKA; JOSEPH SHILOACH; VIRGINIA JOHNSON; DAVID N. TAYLOR; RICHARD A. FINKELSTEIN; JOHN B. ROBBINS; SHOUSUN C. SZU
A total of 146 infants were immunised at ages 2, 3, and 4 months with a combined diphtheria, tetanus, pertussis (DTP)--Haemophilus influenzae type b (Hib) tetanus toxoid conjugate (PRP-T) vaccine (Pasteur Merieux) to assess the antibody response and adverse events associated with immunisation. Adverse events, including fever, were recorded by parents in a diary for three days following each injection. Blood was taken before the first immunisation and four weeks after the third immunisation to assess antibody response. Data were compared with those from historical controls who had received DTP and PRP-T vaccines by separate injection. The combined vaccine was well tolerated. Rates of local and general reactions were similar to those reported for infants immunised by separate injection. All infants achieved protective antibody titres (> 0.01 IU/ml) for diphtheria and tetanus; 98% acquired Hib (PRP) antibody > 0.15 microgram/ml and 82.5% > 1.0 microgram/ml. Pertussis antibody titres (pertussis toxin, filamentous haemagglutinin, total agglutinins, and agglutinins 2 and 3) showed appreciable rise following immunisation. DTP and PRP-T vaccines provide similar antibody responses and adverse effects whether mixed in the same syringe or administered by separate injection. The vaccines could be combined for use in the United Kingdom primary immunisation schedule.
Bell, F; Martin, A; Blondeau, C; Thornton, C; Chaplais, J; Finn, A
The comparative study of the immunological activity of Proteus vaccine prepared from soluble antigenic complexes was made after the immunization of volunteers with this vaccine used in the form of a single preparation and in combination with pyoimmunogen (Pseudomonas aeruginosa vaccine) and/or adsorbed staphylococcal toxoid. The injection of the vaccine in the form of a single preparation and in different combinations increased the ingestion of Proteus cells by neutrophils. The injection of Proteus vaccine simultaneously with pyoimmunogen and staphylococcal toxoid ensured the intensive phagocytosis of staphylococci. All combinations with Proteus vaccine, used in this investigation, stimulated the intensive formation of antibodies to Proteus vaccine strain and Re-glycolipid. Proteus vaccine introduced in combination with adsorbed staphylococcal toxoid essentially stimulated the synthesis of anti-alpha-staphylolysin. PMID:3128030
Levina, L A; Iurova, V A; Kre?nin, L S; Kaverina, K G; Dubova, V G
Induction of Protective Serum Meningococcal Bactericidal and Diphtheria-Neutralizing Antibodies and Mucosal Immunoglobulin A in Volunteers by Nasal Insufflations of the Neisseria meningitidis Serogroup C Polysaccharide-CRM197 Conjugate Vaccine Mixed with Chitosan
Thirty-six healthy volunteers received either a single intramuscular injection of Neisseria meningitidis sero- group C polysaccharide (MCP)-CRM197 conjugate vaccine in alum or two nasal insufflations 28 days apart of the same vaccine powder, without alum, mixed with chitosan. Nasal immunization was well tolerated, with fewer symptoms reported than after intramuscular injection. The geometric mean concentrations of MCP- specific immunoglobulin G
Zhiming Huo; Ruchi Sinha; Edel A. McNeela; Ray Borrow; Rafaela Giemza; Catherine Cosgrove; Paul T. Heath; Kingston H. G. Mills; Rino Rappuoli; George E. Griffin; David J. M. Lewis
Introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in February 2010 markedly reduced the burden of invasive pneumococcal disease (IPD) and changed serotype distribution in Japan. We investigated the serotype distribution and susceptibility trends of non-invasive Streptococcus pneumoniae isolates collected from pediatric patients. A total of 564 pneumococcal isolates were collected over a 5-year period between 2008 and 2012. The coverage of PCV7 significantly decreased throughout the study period, from 49.3% in period 1 (between June 2008 and April 2009) to 23.4% in period 4 (between October 2011 and March 2012). This change was mainly due to a large decrease in the frequency of 19F (from 20.6% to 9.9%) and 6B (from 10.3% to 2.7%) and an increase in serotype 3 (from 5.1% to 13.5%) and serogroup 15 (from 4.4% to 9.0%). According to serotype replacement, the susceptible ratios of S. pneumoniae to ?-lactams increased slightly while macrolide resistance remained high. The high frequency of macrolide-resistant pneumococcal isolates may continue because of the high frequency of erm(B) in replace serotypes such as serotype 3 and serogroup 15. The continuous surveillance study is essential following the introduction of a second generation 13-valent pneumococcal conjugate vaccine (PCV13). PMID:24802765
Okade, Hayato; Funatsu, Tori; Eto, Maki; Furuya, Yuri; Mizunaga, Shingo; Nomura, Nobuhiko; Mitsuyama, Junichi; Yamagishi, Yuka; Mikamo, Hiroshige
Immunogenicity and safety of a tetravalent measles-mumps-rubella-varicella vaccine co-administered with a booster dose of a combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus Haemophilus influenzae type b conjugate vaccine in healthy children aged 12–23 months
This study was undertaken to assess the co-administration of an experimental measles-mumps-rubella-varicella vaccine (MMRV,\\u000a GlaxoSmithKline Biologicals) with a combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus-Haemophilus influenzae type b conjugate (DTPa-HBV-IPV\\/Hib) vaccine in healthy children. Healthy children aged 12–23 months (N?=?451) were randomised to one of three parallel groups to receive one dose of MMRV vaccine co-administered with a booster\\u000a dose of DTPa-HBV-IPV\\/Hib vaccine
Fred Zepp; Ulrich Behre; Klaus Kindler; Karl-Heinz Laakmann; Heidemarie Pankow-Culot; Wilma Mannhardt-Laakmann; François Beckers; Dominique Descamps; Paul Willems
We analyzed eight invasive Haemophilus influenzae strains isolated from individual children vaccinated appropriately for their ages. Five of the strains were type b and three were nontypeable strains. Children infected with nontypeable strains had a protective level of anti-H. influenzae type b antibodies, while only one of the children whose cases represented true vaccine failure did. A small number of
Belen Aracil; Federico Roman; María Perez-Vazquez
Worldwide Haemophilus influenzae Type b Disease at the Beginning of the 21st Century: Global Analysis of the Disease Burden 25 Years after the Use of the Polysaccharide Vaccine and a Decade after the Advent of Conjugates
Vaccination against Haemophilus influenzae type b (Hib) diseases began a quarter of a century ago with a polysaccharide vaccine; this vaccine was followed by four different conjugates 10 years later. In this review, the burden of global Hib disease is quantified following this 25-year period of vaccine availability to determine the potential impact of conjugate vaccines. This task was accomplished by analysis of data available in 10 languages in 75 geographical regions of over 50 countries. All severe Hib diseases, not only meningitis, were characterized, and special attention was paid to the most vulnerable age group, i.e., children aged 0 to 4 years. Prior to vaccination, the weighted worldwide incidence of meningitis in patients younger than 5 years was 57/100,000, and for all Hib diseases except nonbacteremic pneumonia, it was 71/100,000, indicating 357,000 and 445,000 cases per year, respectively. At least 108,500 of these children died. For all age groups combined, there were 486,000 cases of Hib disease, excluding pneumonia, with 114,200 deaths and probably an equal number of sequelae per annum. If the figures for nonbacteremic pneumonia are included, a conservative estimate is that over 2.2 million cases of infection and 520,000 deaths from Hib disease occurred worldwide, but the true numbers might have been greater. Despite these large numbers and availability of safe and efficacious vaccines, only 38,000 cases annually are prevented—a meager 8% or less than a 2% reduction in cases, depending on whether nonbacteremic pneumonia is included in the calculations. Although vaccination has had great success in some affluent countries, the current level of activity has had a very small impact globally. The use of conjugates, preferably with a reduced number of doses and in combination with other vaccines or perhaps in fractional doses, should be extended to less privileged countries, where most Hib disease occurs.
Vaccine development for Group A streptococcal (GAS) infection has been extensively focused on the N-terminal hypervariable or the C-terminal conserved regions of the M protein, a major virulence factor of GAS. We evaluated the immunogenicity and functional activity of the conserved C-terminal peptide vaccine candidate, J8, conjugated to CRM197, in two mouse strains: C3H (H2k) and Balb/c (H2d), and in rhesus macaques. Mice were immunized with J8-CRM197 formulated with Amorphous Aluminum Hydroxyphosphate Sulfate Adjuvant (AAHSA), and non-human primates were immunized with J8-CRM197 formulated with AAHSA, ISCOMATRIXTM adjuvant, or AAHSA/ISCOMATRIX adjuvant. J8-CRM197 was immunogenic in mice from both H2k and H2d backgrounds, and the antibodies generated bound to the surface of four different GAS serotypes and had functional bacterial opsonic activity. Mice immunized with J8-CRM197/AAHSA demonstrated varying degrees of protection from lethal challenge. We also demonstrated that J8-CRM197 is immunogenic in non-human primates. Our data confirm the utility of J8 as a potential GAS vaccine candidate and demonstrate that CRM197 is an acceptable protein carrier for this peptide.
Caro-Aguilar, Ivette; Ottinger, Elizabeth; Hepler, Robert W.; Nahas, Deborah D.; Wu, Chengwei; Good, Michael F.; Batzloff, Michael; Joyce, Joseph G.; Heinrichs, Jon H.; Skinner, Julie M.
Background A large phase III placebo-controlled, randomized efficacy trial of an investigational 11-valent pneumococcal conjugate vaccine against pneumonia in children less than 2 years of age was conducted in the Philippines from July 2000 to December 2004. Clinical data from 12,194 children who were given either study vaccine or placebo was collected from birth up to two years of age for the occurrence of radiologically proven pneumonia as the primary endpoint, and for clinical pneumonia and invasive pneumococcal disease as the secondary endpoints. Several tertiary endpoints were also explored. Along the core trial, several satellite studies on herd immunity, cost-effectiveness of the study vaccine, acute otitis media, and wheezing were conducted. Results We describe here in detail how the relevant clinical records were managed and how quality control procedures were implemented to ensure that valid data were obtained respectively for the core trial and for the satellite studies. We discuss how the task was achieved, what the challenges were and what might have been done differently. Conclusions There were several factors that made the task of data management doable and efficient. First, a pre-trial data management system was available. Secondly, local committed statisticians, programmers and support staff were available and partly familiar to clinical trials. Thirdly, the personnel had undergone training during trial and grew with the task they were supposed to do. Thus the knowledge needed to develop and operate clinical data system was fully transferred to local staff. Trial registration Current Controlled Trials ISRCTN62323832
A total of 79 pre-term infants with a gestational age > or =32 weeks and 74 full-term infants were studied in order to evaluate the immunogenicity, safety and tolerability of meningococcal C (MenC)-CRM(197) conjugate vaccine administered 3, 5 and 11 months post-natally. The evoked immune response seemed to be substantially similar in the pre- and full-term infants, and there were only clinically marginal differences in safety and tolerability between the groups. The results support the use of two doses of MenC-CRM(197) vaccine at 3 and 5 months of age for primary immunisation, with a booster dose being given at about 1 year. In addition to reducing costs, this scheme seems to assure global immunogenicity and potential efficacy that is better than that offered by the accelerated scheme of administration with only three doses of vaccine in the first months of life, and similar to that observed with a fourth dose used as booster after the first year. PMID:17513025
Esposito, Susanna; Corbellini, Barbara; Bosis, Samantha; Pugni, Lorenza; Tremolati, Elena; Tagliabue, Claudia; Toneatto, Daniela; Mosca, Fabio; Principi, Nicola
Non-typeable Haemophilus influenzae (NTHi) outer membrane protein P6 was used as a new protein carrier for NTHi detoxified lipooligosaccharide (dLOS) conjugates due to its conservation and potential to elicit bactericidal antibodies. P6 was covalently conjugated to dLOS of strain 9274 through adipic acid dihydrazide with different ratios of dLOS to P6, which resulted in two conjugate formulations with weight ratios of dLOS to P6 of 3.7 for dLOS-P6 (I) and 1.6 for dLOS-P6 (II). Binding activity of the conjugates was examined by an enzyme-linked immunosorbent assay with mouse monoclonal antibodies specific to LOS and P6 and a rabbit anti-P6 serum. The results showed that the conjugates bound not only to the LOS antibody but also to both P6 antibodies, suggesting that the conjugates retained epitopes of both LOS and P6 antigens. Animal studies revealed that dLOS-P6 (II) induced high levels of anti-LOS and anti-P6 IgGs in mice and rabbits. However, dLOS-P6 (I) induced lower levels of anti-LOS IgGs in mice and rabbits and anti-P6 IgGs in rabbits with no anti-P6 IgGs in mice. In addition, all rabbit, but not mouse, antisera elicited by the conjugates showed bactericidal activity against the homologous strain, and two of them elicited by each conjugate plus Ribi adjuvant showed cross-bactericidal activity against three of five major serotype stains. These data indicate that P6 could serve as an effective carrier for dLOS or other carbohydrate conjugates and that the ratio of carbohydrate to P6 might contribute to immune responses in vivo. PMID:16039021
Wu, Tinghuai; Chen, Jing; Murphy, Timothy F; Green, Bruce A; Gu, Xin-Xing
The use of biodegradable polymer microspheres as a single dose vaccine delivery system was investigated by using tetanus toxoid (TT). In order to compare the immunogenicity of TT-microspheres (TT-MS) with aluminum hydroxide (alum)-based TT, BALBc mice were immunized with TT in different formulations including individual or mixtures of MS and TT-alum. All TT-MS formulations elicited high proliferative and antibody responses
Ying Men; Claudio Thomasin; Hans P. Merkle; Bruno Gander; Giampietro Corradin
... false Clostridium Botulinum Type C Bacterin-Toxoid... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...110 Clostridium Botulinum Type C Bacterin-Toxoid...intraperitoneally with botulinum Type C toxin which has been...
... false Clostridium Botulinum Type C Bacterin-Toxoid... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...110 Clostridium Botulinum Type C Bacterin-Toxoid...intraperitoneally with botulinum Type C toxin which has been...
... false Clostridium Botulinum Type C Bacterin-Toxoid... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...110 Clostridium Botulinum Type C Bacterin-Toxoid...intraperitoneally with botulinum Type C toxin which has been...
Group B Streptococcus (GBS) type III capsular polysaccharide (CPS III) was conjugated to recombinant cholera toxin B subunit (rCTB) using three different methods which employed (i) cystamine and N-succin- imidyl-3-(2-pyridyldithio)propionate (SPDP), (ii) carbodiimide with adipic acid dihydrazide (ADH) as a spacer, or (iii) reductive amination (RA). The CPS III-rCTB conjugates were divided into large- and small- molecular-weight (Mr) fractions, and
XUZHUANG SHEN; T. Lagergard; YONGHONG YANG; MARIANNE LINDBLAD; MARGARETA FREDRIKSSON; JAN HOLMGREN
A meningococcal group A polysaccharide (PS) conjugate vaccine (PsA-TT) has been developed for African countries affected by epidemic meningitis caused by Neisseria meningitidis. Complement-mediated serum bactericidal antibody (SBA) assays are used to assess protective immune responses to meningococcal vaccination. Human complement (hC') was used in early studies demonstrating antibody-mediated protection against disease, but it is difficult to obtain and standardize. We developed and evaluated a method for sourcing hC' and then used the SBA assay with hC' (hSBA) to measure bactericidal responses to PsA-TT vaccination in 12- to 23-month-old African children. Sera with active complement from 100 unvaccinated blood donors were tested for intrinsic bactericidal activity, SBA titer using rabbit complement (rSBA), and anti-group A PS antibody concentration. Performance criteria and pooling strategies were examined and then verified by comparisons of three independently prepared hC' lots in two laboratories. hSBA titers of clinical trial sera were then determined using this complement sourcing method. Two different functional antibody tests were necessary for screening hC'. hSBA titers determined using three independent lots of pooled hC' were within expected assay variation among lots and between laboratories. In African toddlers, PsA-TT elicited higher hSBA titers than meningococcal polysaccharide or Hib vaccines. PsA-TT immunization or PS challenge of PsA-TT-primed subjects resulted in vigorous hSBA memory responses, and titers persisted in boosted groups for over a year. Quantifying SBA using pooled hC' is feasible and showed that PsA-TT was highly immunogenic in African toddlers. PMID:24671551
Bash, Margaret C; Lynn, Freyja; Mocca, Brian; Borrow, Ray; Findlow, Helen; Hassan-King, Musa; Preziosi, Marie-Pierre; Idoko, Olubukola; Sow, Samba; Kulkarni, Prasad; Laforce, F Marc
To investigate the trends in incidence and the characteristics of bacterial meningitis in Japan where Haemophilus influenzae type b (Hib) vaccine and 7-valent pneumococcal conjugated vaccine (PCV7) were introduced in 2008 and 2010, respectively, which was 5-20 years after their introduction in western countries. The nationwide Japanese survey of pediatric and neonatal bacterial meningitis was performed in 2011 and 2012. We analyzed the epidemiological and clinical data, and compared the information obtained in the previous nationwide survey database. We also investigated the risk factors for disease outcome. In the 2011-2012 surveys, 357 patients were evaluated. H. influenzae, Streptococcus pneumoniae, Streptococcus agalactiae and Escherichia coli were the main organisms. The number of patients hospitalized with bacterial meningitis per 1000 admissions decreased from 1.31 in 2009 to 0.43 in 2012 (p < 0.001). The incidence of H. influenzae and S. pneumoniae meningitis also decreased from 0.66 to 0.08 (p < 0.001), and 0.30 to 0.06 (p < 0.001), respectively. Only 0-2 cases with Neisseria meningitidis were reported each year throughout 2001-2012. The median patient age was 10-12 months in 2001-2011, and became lower in 2012 (2 month old) (p < 0.001). The fatality rate for S. agalactiae is the highest (5.9% (11/187)) throughout 2001-2012 among the four organisms. Risk factors for death and sequelae were convulsions at onset, low CSF glucose, S. agalactiae etiology, and persistent positive CSF culture. Hib vaccine and PCV7 decreased the rate of bacterial meningitis. Earlier introduction of these vaccines may have prevented bacterial meningitis among Japanese children. PMID:24855913
Shinjoh, Masayoshi; Iwata, Satoshi; Yagihashi, Tatsuhiko; Sato, Yoshitake; Akita, Hironobu; Takahashi, Takao; Sunakawa, Keisuke
Results The greatest risk factor for pneumonia among children ? 2 years of age was day-care centre attendance (P ? 0.001). Of the study participants, 83.3% (1072\\/1287) were classified as vaccinated according to immunization card and 16.7% (215\\/1287) were considered unvaccinated. By using conditional logistic regression the vaccine effectiveness was estimated as 31.0% (95% CI: ? 9.0%, 57.0%) after adjusting
João Guimarães de Andrade; Celina Maria Turchi Martelli; Simonne Almeida; Renato Maurício de Oliveira; Maria Selma Neves Costa; Cristina Borges Laval; Luiza Helena; Vilela Ribeiro; Jose Luis Di Fabio
A single dose of 15 ?g (0·6 mg/kg) Actinomycin-D administered to female BDF1 mice after intraperitoneal injections of pertussis vaccine and tetanus toxoid caused: (1) a prolonged depression in thymic and splenic weights; (2) an inhibition of the bone marrow leucocytosis which normally occurs between the 2nd and 14th days after antigen injection; (3) a blood leucopenia and marked decrease in the number of mononuclear cells in the inflammatory exudate during both the primary response and a secondary response initiated 4 weeks later; and (4) an inhibition of primary immunization, as evidenced by low antitoxin titres 4 weeks after priming, and by the failure to achieve a normal secondary response to a challenging injection of antigen given 4 weeks later. It was suggested that the sensitivity of mononuclear cells to Actinomycin-D may be responsible for the suppression of priming, possibly by preventing RNA synthesis and differentiation induced by antigen.
Geller, B. D.; Speirs, R. S.
Background The relationship between pneumococcal conjugate vaccine–induced antibody responses and protection against community-acquired pneumonia (CAP) and acute otitis media (AOM) is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) on these end points. The primary objective was to demonstrate vaccine efficacy (VE) in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ? 40 µg/ml); other protocol-specified outcomes were also assessed. Methods and Findings This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster) at 2, 4, 6, and 15–18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ?2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n?=?10,295; control, n?=?10,201), per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p?=?0.002) against B-CAP (conclusive for primary objective) and 25.7% (95% CI: 8.4%, 39.6%) against World Health Organization–defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1%) against B-CAP and 23.4% (95% CI: 8.8%, 35.7%) against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28–30 mo for CAP and invasive pneumococcal disease (IPD) (PHiD-CV, n?=?10,211; control, n?=?10,140) and AOM (n?=?3,010 and 2,979, respectively). Per-protocol VE was 16.1% (95% CI: ?1.1%, 30.4%; one-sided p?=?0.032) against clinically confirmed AOM, 67.1% (95% CI: 17.0%, 86.9%) against vaccine serotype clinically confirmed AOM, 100% (95% CI: 74.3%, 100%) against vaccine serotype IPD, and 65.0% (95% CI: 11.1%, 86.2%) against any IPD. Results were consistent between intent-to-treat and per-protocol analyses. Serious adverse events were reported for 21.5% (95% CI: 20.7%, 22.2%) and 22.6% (95% CI: 21.9%, 23.4%) of PHiD-CV and control recipients, respectively. There were 19 deaths (n?=?11,798; 0.16%) in the PHiD-CV group and 26 deaths (n?=?11,799; 0.22%) in the control group. A significant study limitation was the lower than expected number of captured AOM cases. Conclusions Efficacy was demonstrated against a broad range of pneumococcal diseases commonly encountered in young children in clinical practice. Trial registration www.ClinicalTrials.gov NCT00466947 Please see later in the article for the Editors' Summary
Tregnaghi, Miguel W.; Saez-Llorens, Xavier; Lopez, Pio; Abate, Hector; Smith, Enrique; Posleman, Adriana; Calvo, Arlene; Wong, Digna; Cortes-Barbosa, Carlos; Ceballos, Ana; Tregnaghi, Marcelo; Sierra, Alexandra; Rodriguez, Mirna; Troitino, Marisol; Carabajal, Carlos; Falaschi, Andrea; Leandro, Ana; Castrejon, Maria Mercedes; Lepetic, Alejandro; Lommel, Patricia; Hausdorff, William P.; Borys, Dorota; Guinazu, Javier Ruiz; Ortega-Barria, Eduardo; Yarzabal, Juan P.; Schuerman, Lode
Does a 10-valent pneumococcal-Haemophilus influenzae protein D conjugate vaccine prevent respiratory exacerbations in children with recurrent protracted bacterial bronchitis, chronic suppurative lung disease and bronchiectasis: protocol for a randomised controlled trial
Background Recurrent protracted bacterial bronchitis (PBB), chronic suppurative lung disease (CSLD) and bronchiectasis are characterised by a chronic wet cough and are important causes of childhood respiratory morbidity globally. Haemophilus influenzae and Streptococcus pneumoniae are the most commonly associated pathogens. As respiratory exacerbations impair quality of life and may be associated with disease progression, we will determine if the novel 10-valent pneumococcal-Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) reduces exacerbations in these children. Methods A multi-centre, parallel group, double-blind, randomised controlled trial in tertiary paediatric centres from three Australian cities is planned. Two hundred six children aged 18 months to 14 years with recurrent PBB, CSLD or bronchiectasis will be randomised to receive either two doses of PHiD-CV or control meningococcal (ACYW135) conjugate vaccine 2 months apart and followed for 12 months after the second vaccine dose. Randomisation will be stratified by site, age (<6 years and ?6 years) and aetiology (recurrent PBB or CSLD/bronchiectasis). Clinical histories, respiratory status (including spirometry in children aged ?6 years), nasopharyngeal and saliva swabs, and serum will be collected at baseline and at 2, 3, 8 and 14 months post-enrolment. Local and systemic reactions will be recorded on daily diaries for 7 and 30 days, respectively, following each vaccine dose and serious adverse events monitored throughout the trial. Fortnightly, parental contact will help record respiratory exacerbations. The primary outcome is the incidence of respiratory exacerbations in the 12 months following the second vaccine dose. Secondary outcomes include: nasopharyngeal carriage of H. influenzae and S. pneumoniae vaccine and vaccine- related serotypes; systemic and mucosal immune responses to H. influenzae proteins and S. pneumoniae vaccine and vaccine-related serotypes; impact upon lung function in children aged ?6 years; and vaccine safety. Discussion As H. influenzae is the most common bacterial pathogen associated with these chronic respiratory diseases in children, a novel pneumococcal conjugate vaccine that also impacts upon H. influenzae and helps prevent respiratory exacerbations would assist clinical management with potential short- and long-term health benefits. Our study will be the first to assess vaccine efficacy targeting H. influenzae in children with recurrent PBB, CSLD and bronchiectasis. Trial registration Australia and New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12612000034831.
7-Valent pneumococcal conjugate vaccine (PCV7) immunization in adulthood can inhibit allergic asthma in mouse model. The aim of this study is to investigate the effects of infant PCV7 immunization on young adulthood CD4(+)T cell subsets in a murine allergic airway disease (AAD) model. Our study indicated that infant PCV7 immunization can inhibit young adulthood airway inflammation and airway hyperresponsiveness (AHR) by inducing the production of Foxp3(+)Treg, Th1 cells and their cytokines IL-10 and IFN-?, inhibiting the production of Th2, Th17 cells and their cytokines IL-13 and IL-17A in BALB/c mice model. These results suggested that infant PCV7 immunization may serve as an effective measure to prevent young adulthood mice AAD. PMID:24560673
Zhang, Liqun; Gao, Hui; Yang, Ting; Yang, Baohui; Jiang, Xiaoli; Wang, Lijia; Wang, Qinghong; Luo, Zhengxiu; Liu, Enmei; Fu, Zhou
Injectable silicone implants were assessed as vaccine delivery vehicles in sheep, using either the model antigen avidin or Clostridium tetani and Clostridium novyi toxoids. Two types of implant were compared, the matrix type, that has been shown to deliver antigen in vitro in a first-order profile over approximately 1 month, and the covered rod type, that delivers antigen for several
S. A Lofthouse; M Kajihara; S Nagahara; A Nash; G. J Barcham; B Sedgmen; M. R Brandon; A Sano
Background Combining meningococcal vaccination with routine immunization in infancy may reduce the burden of meningococcal meningitis, especially in the meningitis belt of Africa. We have evaluated the immunogenicity, persistence of immune response, immune memory and safety of an investigational DTPw-HBV/Hib-MenAC conjugate vaccine given to infants in Northern Ghana. Methods and Findings In this phase II, double blind, randomized, controlled study, 280 infants were primed with DTPw-HBV/Hib-MenAC or DTPw-HBV/Hib vaccines at 6, 10 and 14 weeks of age. At 12 months of age, children in each group received a challenge dose of serogroup A+C polysaccharides. Antibody responses were assessed pre, and one month-post dose 3 of the priming schedule and pre and 1 month after administration of the challenge dose. One month post-dose 3, 87.8% and 88.2% of subjects in the study group had bactericidal meningococcal serogroup A (SBA-MenA) and meningococcal serogroup C (SBA-MenC) antibody titres ?1?8 respectively. Seroprotection/seropositivity rates to the 5 antigens administered in the routine EPI schedule were non-inferior in children in the study group compared to those in the control group. The percentages of subjects in the study group with persisting SBA-MenA titres ? 1?8 or SBA-MenC titres ?1?8 at the age of 12 months prior to challenge were significantly higher than in control group (47.7% vs 25.7% and 56.4% vs 5.1% respectively). The administration of 10 ?g of serogroup A polysaccharide increased the SBA-MenA GMT by 14.0-fold in the DTPW-HBV/HibMenAC-group compared to a 3.8 fold increase in the control-group. Corresponding fold-increases in SBA-MenC titres following challenge with 10 ?g of group C polysaccharide were 18.8 and 1.9 respectively. Reactogenicity following primary vaccination or the administration of the challenge dose was similar in both groups, except for swelling (Grade 3) after primary vaccination which was more frequent in children in the vaccine than in the control group (23.7%; 95%CI [19.6–28.1] of doses vs 14.1%; 95% CI [10.9–17.8] of doses). Fifty-nine SAEs (including 8 deaths), none of them related to vaccination, were reported during the entire study. Conclusions Three dose primary vaccination with DTPw-HBV/Hib-MenAC was non-inferior to DTPw-HBV/Hib for the 5 common antigens used in the routine EPI schedule and induced bactericidal antibodies against Neisseria meningitidis of serogroups A and C in the majority of infants. Serogroup A and C bactericidal antibody levels had fallen below titres associated with protection in nearly half of the infants by the age of 12 months confirming that a booster dose is required at about that age. An enhanced memory response was shown after polysaccharide challenge. This vaccine could provide protection against 7 important childhood diseases (including meningococcal A and C) and be of particular value in countries of the African meningitis belt. Trial Registration Controlled-Trials.com ISRCTN35754083
Hodgson, Abraham; Forgor, Abudulai Adams; Chandramohan, Daniel; Reed, Zarifah; Binka, Fred; Bevilacqua, Cornelia; Boutriau, Dominique; Greenwood, Brian
Decreasing incidence and changes in serotype distribution of invasive pneumococcal disease in persons aged under 18 years since introduction of 10-valent and 13-valent conjugate vaccines in Portugal, July 2008 to June 2012.
The 10-valent pneumococcal conjugate vaccine (PCV10) became available in Portugal in mid-2009 and the 13-valent vaccine (PCV13) in early 2010. The incidence of invasive pneumococcal disease (IPD) in patients aged under 18 years decreased from 8.19 cases per 100,000 in 2008–09 to 4.52/100,000 in 2011–12. However, IPD incidence due to the serotypes included in the 7-valent conjugate vaccine (PCV7) in children aged under two years remained constant. This fall resulted from significant decreases in the number of cases due to: (i) the additional serotypes included in PCV10 and PCV13 (1, 5, 7F; from 37.6% to 20.6%), particularly serotype 1 in older children; and (ii) the additional serotypes included in PCV13 (3, 6A, 19A; from 31.6% to 16.2%), particularly serotype 19A in younger children. The decrease in serotype 19A before vaccination indicates that it was not triggered by PCV13 administration. The decrease of serotype 1 in all groups, concomitant with the introduction of PCV10, is also unlikely to have been triggered by vaccination, although PCVs may have intensified and supported these trends. PCV13 serotypes remain major causes of IPD, accounting for 63.2% of isolates recovered in Portugal in 2011–12, highlighting the potential role of enhanced vaccination in reducing paediatric IPD in Portugal. PMID:24698140
Aguiar, S I; Brito, M J; Horacio, A N; Lopes, J P; Ramirez, M; Melo-Cristino, J
Data suggest that the O-specific polysaccharide (O-SP) domain of the lipopolysaccharide (LPS) of Shigella species is both an essential virulence factor and a protective antigen and that a critical level of serum immunoglobulin G (IgG) to this antigen will confer immunity to shigellosis. Because covalent attachment of polysaccharides to proteins increases their immunogenicity, especially in infants and in young children, the O-SP of Shigella species were bound to medically useful proteins, and the safety and immunogenicity of the resultant conjugates were confirmed in adults and 4- to 7-year-old children. Succinylation of the carrier protein improved the immunogenicity of Shigella conjugates in mice and increased their yield. Based on these results, a clinical trial of O-SP conjugates of Shigella sonnei and Shigella flexneri 2a bound to succinylated mutant Pseudomonas aeruginosa exotoxin A (rEPAsucc) or native or succinylated Corynebacterium diphtheriae toxin mutant (CRM9 or CRM9succ) was conducted in healthy adults. The conjugates were safe and immunogenic. S. sonnei-CRM9, S. sonnei-CRM9succ, and S. sonnei-rEPAsucc elicited significant rises of geometric mean (GM) IgG anti-LPS within 1 week of injection (P < 0.001). At 26 weeks, the GM anti-LPS levels elicited by these three conjugates were similar and higher than their prevaccination levels (P < 0.0001). GM IgG anti-LPS levels elicited by S. flexneri 2a-rEPAsucc were significantly higher than those elicited by S. flexneri 2a-rCRM9succ at all intervals after injection. At 26 weeks, the levels of IgG anti-LPS in vaccinees were higher than their prevaccination levels (P < 0.0001). The serum antibody responses were specific, as there was no significant rise of anti-LPS to the heterologous O-SP in any vaccinee. Both conjugates elicited statistically significant rises of serum antibodies to the injected carrier protein. At 6 months, these five Shigella conjugates elicited higher fold rises than similar conjugates (D. N. Taylor et al., Infect. Immun. 61:3678–3687, 1993). Based on these data, we chose S. sonnei-CRM9 and S. flexneri 2a-rEPAsucc for evaluation in children.
Passwell, Justen H.; Harlev, Efrat; Ashkenazi, Shai; Chu, Chiayung; Miron, Dan; Ramon, Reut; Farzan, Naheed; Shiloach, Joseph; Bryla, Dolores A.; Majadly, Fathy; Roberson, Robin; Robbins, John B.; Schneerson, Rachel
We measured IgA and IgG antibodies to pertussis toxin (PT) and filamentous hemagglutinin (FHA) in sera from 203 1-year-old children who had received one to three doses of a monocomponent PT toxoid vaccine. Ten children (5%) had IgA antibody to PT indicating recent infection; seven of these children had received three doses of vaccine. PT IgA responders did not have significantly longer coughing episodes than PT IgA non-responders. Since an IgA antibody response occurs in only ?50% of infected children, the actual infection rate in our cohort is estimated to ?10%. The apparent high Bordetella pertussis infection rate in Danish infants suggests that the monocomponent PT toxoid vaccine used in Denmark has limited efficacy against B. pertussis infection. A prospective immunization study comparing a multi-component vaccine with the present monocomponent PT toxoid vaccine should be undertaken.
von Linstow, Marie-Louise; Pontoppidan, Peter Lotko; von Konig, Carl-Heinz Wirsing; Hogh, Birthe
Haemophilus influenzae type b (Hib) conjugate vaccine for infants (6, 10, and 14 weeks of age) was introduced into the Malian Expanded Program on Immunization in July 2005, to diminish invasive Hib disease in young children. Antibodies to Hib capsular polysaccharide (PRP) were measured in infants and toddlers from an area already served by the Hib immunization program (Bamako) and in unimmunized children of the same age in a district (Kangaba) where Hib immunization had not yet begun. Among vaccinated Bamako children 6–23 months of age, 77–93% exhibited PRP titers ? 1.0 ?g/mL, indicating long-term protection, versus only 10–23% of Kangaba children of that age. High PRP antibody titers in immunized children persisted through 2 years of age. Moreover, ?50% of Bamako children exhibited anti-PRP titers ? 5.0 ?g/mL; a level that impedes Hib upper respiratory carriage, and may thereby diminish the Hib transmission to the unimmunized susceptible population (i.e., providing indirect protection).
Hutter, Julia; Pasetti, Marcela F.; Sanogo, Doh; Tapia, Milagritos D.; Sow, Samba O.; Levine, Myron M.
Oligosaccharide (OS)-protein conjugates are promising candidate vaccinesagainst encapsulated bacteria, such as Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae. Although the effects of several variables such as OS chain length and protein carrier have been studied, little is known about the influence of adjuvants on the immunogenicity of OS-protein conjugates. In this study, a minimal protective trisaccharide epitope of Streptococcus pneumoniae type 3 conjugated to the cross-reacting material of diphtheria toxin was used for immunization of BALB/c mice in the presence of different adjuvants. Subsequently, half of the mice received a booster immunization with conjugate alone. Independent of the use and type of adjuvant, all mice produced long-lasting anti-polysaccharide type 3 (PS3) antibody levels, which provided full protection against challenge with pneumococcal type 3 bacteria. All adjuvants tested increased the anti-PS3 antibody levels and opsonic capacities as measured by an enzyme-linked immunosorbent assay and an in vitro phagocytosis assay. The use of QuilA or a combination of the adjuvants CpG and dimethyl dioctadecyl ammonium bromide resulted in the highest phagocytic capacities and the highest levels of Th1-related immunoglobulin G (IgG) subclasses. Phagocytic capacity correlated strongly with Th1-associated IgG2a and IgG2b levels, to a lesser extent with Th2-associated IgG1 levels, and weakly with thiocyanate elution as a measure of avidity. Thus, the improved immunogenicity of OS-protein conjugates was most pronounced for Th1-directing adjuvants.
Lefeber, Dirk J.; Benaissa-Trouw, Barry; Vliegenthart, Johannes F. G.; Kamerling, Johannis P.; Jansen, Wouter T. M.; Kraaijeveld, Kees; Snippe, Harm
We review the major advances that have recently occurred in the area of antifertility vaccines by examining the immunogenic potential of gamete, embryonic and placental antigens. In human trials using ?-human chorionic gonadotropin coupled with tetanus toxoid as the immunogen, the major problems with antifertility vaccines relate to specificity and maintaining an adequate antibody titer to disrupt gestation. Possible complications include cross-reaction with other body tissues, immune complex deposition, cytotoxicity, impaired immunologic tumor surveillance and nonreversibility.
Moore, Donald E.; Covey, Dana C.; O'Brien, Kelvin D.
A bivalent conjugate vaccine in the treatment of biochemically relapsed prostate cancer: a study of glycosylated MUC2KLH and Globo HKLH conjugate vaccines given with the new semi-synthetic saponin immunological adjuvant GPI-0100 OR QS-21
GPI-0100 is a semi-synthetic saponin with modifications designed to augment stability and diminish toxicity. Two batches of GPI-0100 (the second with higher purity) were tested with doses ranging between 100 and 5000?g in groups of five treated prostate cancer patients who had no evidence of disease except for rising PSA levels. GPI-0100 was mixed with a bivalent vaccine containing the
Susan F. Slovin; Govind Ragupathi; Celina Fernandez; Matthew P. Jefferson; Meghan Diani; Andrew S. Wilton; Shemeeakah Powell; Maria Spassova; Celso Reis; Henrick Clausen; Samuel Danishefsky; Philip Livingston; Howard I. Scher
The capsular polysaccharide of Salmonella typhi, Vi, is an essential virulence factor and a protective vaccine for people older than 5 years. The safety and immunogenicity of two investigational Vi conjugate vaccines were evaluated in adults, 5- to 14-year-old children, and 2- to 4-year-old children in Vietnam. The conjugates were prepared with Pseudomonas aeruginosa recombinant exoprotein A (rEPA) as the carrier, using either N-succinimidyl-3-(2-pyridyldithio)-propionate (SPDP; Vi-rEPA(1)) or adipic acid dihydrazide (ADH; Vi-rEPA(2)) as linkers. None of the recipients experienced a temperature of >38.5 degrees C or significant local reactions. One injection of Vi-rEPA(2) into adults elicited a geometric mean (GM) increase in anti-Vi immunoglobulin G (IgG) from 9.62 enzyme-linked immunosorbent assay units/ml (EU) to 465 EU at 6 weeks; this level fell to 119 EU after 26 weeks. In the 5- to 14-year-old children, anti-Vi IgG levels at 6 weeks elicited by Vi-rEPA(2), Vi-rEPA(1), and Vi were 169, 22.8, and 18.9 EU, respectively (P = 0.0001 for Vi-rEPA(1) and Vi with respect to Vi-rEPA(2)). At 26 weeks, the anti-Vi IgG levels for recipients of Vi-rEPA(2), Vi-rEPA(1), and Vi were 30.0, 10.8, and 13.4 EU, respectively (P < 0.001 for Vi-rEPA(1) and Vi with respect to Vi-rEPA(2)); all were higher than the preinjection levels (P = 0. 0001). Vi-rEPA(2) also elicited the highest anti-Vi IgM and IgA levels of the three vaccines. In the 2- to 4-year-old children at 6 weeks following the first injection, Vi-rEPA(2) elicited an anti-Vi IgG level of 69.9 EU compared to 28.9 EU for Vi-rEPA(1) (P = 0.0001). Reinjection increased Vi antibody levels from 69.9 to 95.4 EU for Vi-rEPA(2) and from 28.9 to 83.0 EU for Vi-rEPA(1). At 26 weeks, anti-Vi IgG levels remained higher than those at preinjection (30.6 versus 0.18 for Vi-rEPA(2) and 12.8 versus 0.33 for Vi-rEPA(1); P = 0.0001 for both). Vi vaccine is recommended for individuals of 5 years of age or older. In the present study, the GM level of anti-Vi IgG elicited by two injections of Vi-rEPA(2) in the 2- to 4-year-old children was higher than that elicited by Vi in the 5- to 14-year-old children (30.6 versus 13.4; P = 0.0001). The safety and immunogenicity of the Vi-rEPA(2) conjugate warrant further investigation. PMID:10531232
Kossaczka, Z; Lin, F Y; Ho, V A; Thuy, N T; Van Bay, P; Thanh, T C; Khiem, H B; Trach, D D; Karpas, A; Hunt, S; Bryla, D A; Schneerson, R; Robbins, J B; Szu, S C
The capsular polysaccharide of Salmonella typhi, Vi, is an essential virulence factor and a protective vaccine for people older than 5 years. The safety and immunogenicity of two investigational Vi conjugate vaccines were evaluated in adults, 5- to 14-year-old children, and 2- to 4-year-old children in Vietnam. The conjugates were prepared with Pseudomonas aeruginosa recombinant exoprotein A (rEPA) as the carrier, using either N-succinimidyl-3-(2-pyridyldithio)-propionate (SPDP; Vi-rEPA1) or adipic acid dihydrazide (ADH; Vi-rEPA2) as linkers. None of the recipients experienced a temperature of >38.5°C or significant local reactions. One injection of Vi-rEPA2 into adults elicited a geometric mean (GM) increase in anti-Vi immunoglobulin G (IgG) from 9.62 enzyme-linked immunosorbent assay units/ml (EU) to 465 EU at 6 weeks; this level fell to 119 EU after 26 weeks. In the 5- to 14-year-old children, anti-Vi IgG levels at 6 weeks elicited by Vi-rEPA2, Vi-rEPA1, and Vi were 169, 22.8, and 18.9 EU, respectively (P = 0.0001 for Vi-rEPA1 and Vi with respect to Vi-rEPA2). At 26 weeks, the anti-Vi IgG levels for recipients of Vi-rEPA2, Vi-rEPA1, and Vi were 30.0, 10.8, and 13.4 EU, respectively (P < 0.001 for Vi-rEPA1 and Vi with respect to Vi-rEPA2); all were higher than the preinjection levels (P = 0.0001). Vi-rEPA2 also elicited the highest anti-Vi IgM and IgA levels of the three vaccines. In the 2- to 4-year-old children at 6 weeks following the first injection, Vi-rEPA2 elicited an anti-Vi IgG level of 69.9 EU compared to 28.9 EU for Vi-rEPA1 (P = 0.0001). Reinjection increased Vi antibody levels from 69.9 to 95.4 EU for Vi-rEPA2 and from 28.9 to 83.0 EU for Vi-rEPA1. At 26 weeks, anti-Vi IgG levels remained higher than those at preinjection (30.6 versus 0.18 for Vi-rEPA2 and 12.8 versus 0.33 for Vi-rEPA1; P = 0.0001 for both). Vi vaccine is recommended for individuals of 5 years of age or older. In the present study, the GM level of anti-Vi IgG elicited by two injections of Vi-rEPA2 in the 2- to 4-year-old children was higher than that elicited by Vi in the 5- to 14-year-old children (30.6 versus 13.4; P = 0.0001). The safety and immunogenicity of the Vi-rEPA2 conjugate warrant further investigation.
Kossaczka, Zuzana; Lin, Feng-Ying C.; Ho, Vo Anh; Thuy, Nguyen Thi Thanh; Bay, Phan Van; Thanh, Tran Cong; Khiem, Ha Ba; Trach, Dang Duc; Karpas, Arthur; Hunt, Steven; Bryla, Dolores A.; Schneerson, Rachel; Robbins, John B.; Szu, Shousun C.
Immunogenicity and Safety of a Multicomponent Meningococcal Serogroup B Vaccine and a Quadrivalent Meningococcal CRM197 Conjugate Vaccine against Serogroups A, C, W-135, and Y in Adults Who Are at Increased Risk for Occupational Exposure to Meningococcal Isolates?
Laboratory staff who work with meningococcal isolates are at increased risk for developing invasive disease relative to the general population. This was the first study of laboratory workers who received both a conjugate vaccine against meningococcal serogroups A, C, W-135, and Y (Men ACWY-CRM, Menveo) and an investigational multicomponent vaccine against serogroup B containing factor H binding protein, neisserial adhesin A, Neisseria heparin binding antigen, and New Zealand strain outer membrane vesicles (4CMenB). Healthy adults (18 to 50 years of age) received three doses of 4CMenB at baseline, 2 months, and 6 months followed by a single dose of MenACWY-CRM 1 month later. Immunogenicity was assessed via serum bactericidal assay using human complement (hSBA) at 1 month postvaccination; solicited reactogenicity and adverse events were monitored. Fifty-four participants enrolled. Bactericidal immune responses were evident after each dose of 4CMenB, as assessed by hSBA geometric mean titers and percentages of subjects with hSBA titers of ?4 against the test strains or a 4-fold rise in titer over baseline. At 1 month postvaccination, most MenACWY-CRM recipients had hSBA titers of ?8 against serogroups A, C, W-135, and Y. Few participants discontinued due to an adverse event or vaccine reaction. Rates of solicited reactions were lower after MenACWY-CRM than after 4CMenB administration. Sequential administration of 4CMenB and MenACWY-CRM provided robust evidence of an immune response against serogroups A, B, C, W-135, and Y in laboratory workers routinely exposed to meningococcal isolates.
Kimura, Alan; Toneatto, Daniela; Kleinschmidt, Annett; Wang, Huajun; Dull, Peter
Immunogenicity and safety of a multicomponent meningococcal serogroup B vaccine and a quadrivalent meningococcal CRM197 conjugate vaccine against serogroups A, C, W-135, and Y in adults who are at increased risk for occupational exposure to meningococcal isolates.
Laboratory staff who work with meningococcal isolates are at increased risk for developing invasive disease relative to the general population. This was the first study of laboratory workers who received both a conjugate vaccine against meningococcal serogroups A, C, W-135, and Y (Men ACWY-CRM, Menveo) and an investigational multicomponent vaccine against serogroup B containing factor H binding protein, neisserial adhesin A, Neisseria heparin binding antigen, and New Zealand strain outer membrane vesicles (4CMenB). Healthy adults (18 to 50 years of age) received three doses of 4CMenB at baseline, 2 months, and 6 months followed by a single dose of MenACWY-CRM 1 month later. Immunogenicity was assessed via serum bactericidal assay using human complement (hSBA) at 1 month postvaccination; solicited reactogenicity and adverse events were monitored. Fifty-four participants enrolled. Bactericidal immune responses were evident after each dose of 4CMenB, as assessed by hSBA geometric mean titers and percentages of subjects with hSBA titers of ?4 against the test strains or a 4-fold rise in titer over baseline. At 1 month postvaccination, most MenACWY-CRM recipients had hSBA titers of ?8 against serogroups A, C, W-135, and Y. Few participants discontinued due to an adverse event or vaccine reaction. Rates of solicited reactions were lower after MenACWY-CRM than after 4CMenB administration. Sequential administration of 4CMenB and MenACWY-CRM provided robust evidence of an immune response against serogroups A, B, C, W-135, and Y in laboratory workers routinely exposed to meningococcal isolates. PMID:21177912
Kimura, Alan; Toneatto, Daniela; Kleinschmidt, Annett; Wang, Huajun; Dull, Peter
Background The World Allergy Organization in 2011 estimated that 30 to 40% of the world population is now affected by one or more allergic conditions. Since the IgE plays a central role in the expansion and regulation of allergic response that seems the IgE elimination is the best approach in the control of asthma and allergic diseases. Now, an anti-IgE antibody as a drug (Xolair) is available and efficient but is expensive with short half-life. As good and more efficient substitution IgE peptide-based vaccines has been proposed. Methods In this study, we analyzed all potential antigenic peptides on the constant region of the Ig epsilon chain (Fc?). For determination of B cell immunodominant epitope, we used the antibody epitope prediction tools. In continuing candidate peptides were done BlastP to avoid nonspecific antibody reactions with other human proteins in the NCBI database. And then, to preparation of vaccines, peptides were synthesized and conjugated by Tetanus toxoid (TT). To immunogenicity analysis of vaccines, the rats are being immunized with vaccines or TT as control. Results By Kolaskar and Tongaonkar antigenicity algorithms 20 peptides with putative epitopes were selected. Homologous sequences and also previous studies peptides were excluded, 13 peptides remained that used for vaccine preparation. The produced vaccines are being analyzed for their effect on induction of anti-IgE antibody production. Peptides based on antibody production or not, were divided in 2 groups. Conclusions Active immunization by IgE peptide based vaccines can be triggering production antibodies against self-IgE that are effective in preventing and control of IgE levels as an important factor in asthma and allergic diseases.
Kardar, Gholam Ali; Shahandashtic, Tina; Zarec, Ahad
Background Neonatal tetanus remains an important and preventable cause of neonatal mortality globally. Large reductions in neonatal tetanus deaths have been reported following major increases in the coverage of tetanus toxoid immunization, yet the level of evidence for the mortality effect of tetanus toxoid immunization is surprisingly weak with only two trials considered in a Cochrane review. Objective To review the evidence for and estimate the effect on neonatal tetanus mortality of immunization with tetanus toxoid of pregnant women, or women of childbearing age. Methods We conducted a systematic review of multiple databases. Standardized abstraction forms were used. Individual study quality and the overall quality of evidence were assessed using an adaptation of the GRADE approach. Meta-analyses were performed. Results Only one randomised controlled trial (RCT) and one well-controlled cohort study were identified, which met inclusion criteria for meta-analysis. Immunization of pregnant women or women of childbearing age with at least two doses of tetanus toxoid is estimated to reduce mortality from neonatal tetanus by 94% [95% confidence interval (CI) 80–98%]. Additionally, another RCT with a case definition based on day of death, 3 case–control studies and 1 before-and-after study gave consistent results. Based on the consistency of the mortality data, the very large effect size and that the data are all from low/middle-income countries, the overall quality of the evidence was judged to be moderate. Conclusion This review uses a standard approach to provide a transparent estimate of the high impact of tetanus toxoid immunization on neonatal tetanus.
Blencowe, Hannah; Lawn, Joy; Vandelaer, Jos; Roper, Martha
Worldwide, invasive meningococcal disease affects about 500,000 people annually. Case fatality in developed countries averages 10%, and higher rates are reported in less prosperous regions. According to the World Health Organization, the most important pathogenic serogroups are A, B, C, W-135, X, and Y. Clinical features of invasive meningococcal disease make diagnosis and management difficult. Antibiotic measures are recommended for prophylaxis after exposure and for treatment of invasive meningococcal disease cases; however, resistant strains may be emerging. Vaccines are generally regarded as the best preventative measure for invasive meningococcal disease. Polysaccharide vaccines against serogroups A, C, W-135, and Y using protein conjugation technology have clear advantages over older plain polysaccharide formulations without a protein component. The first quadrivalent meningococcal conjugate vaccine (MenACWY-D) was licensed in the US in 2005. More recently, MenACWY-CRM (Menveo®) was licensed in Europe, the US, the Middle East, and Latin America. MenACWY-CRM uses cross-reactive material 197, a nontoxic mutant of diphtheria toxin, as the carrier protein. MenACWY-CRM offers robust immunogenicity in all age groups, with a tolerability profile similar to that of a plain polysaccharide vaccine. Given its potential for protecting persons from infancy to old age, MenACWY-CRM offers the opportunity to protect broad populations against invasive meningococcal disease. The most optimal strategy for use of the vaccine has to be assessed country by country on the basis of local epidemiology, individual health care systems, and need.
Broker, Michael; Cooper, Brian; DeTora, Lisa M; Stoddard, Jeffrey J
The magnitude of the antibody and memory B cell responses during priming with a protein-polysaccharide conjugate vaccine in human infants is associated with the persistence of antibody and the intensity of booster response.
Rapid waning of anti-polysaccharide bactericidal Ab and vaccine effectiveness is observed following infant immunization with the serogroup C meningococcal (MenC) glycoconjugate vaccine. This is despite the demonstrable presence of immunological memory. Persistence of functional Ab, therefore, appears to be the key determinant of MenC conjugate vaccine effectiveness. Ab persistence is thought to depend in the short term on the survival of plasma cells generated during priming and in the longer term on the production of new Ab secreting cells from memory B cells. In this study, we found a strong association between the level of MenC-specific Ab and the frequency of memory B cells measured at 5 mo of age (1 mo after 3-dose primary immunization with MenC conjugate vaccine), and the persistence of functional Ab at one year of age. These findings suggest that these two parameters are good markers of B cell responses to priming and can be used as predictors of long term humoral immunity induced by glycoconjugate vaccines received in early infancy. PMID:18250423
Blanchard Rohner, Geraldine; Snape, Matthew D; Kelly, Dominic F; John, Tessa; Morant, Anita; Yu, Ly-Mee; Borkowski, Astrid; Ceddia, Francesca; Borrow, Ray; Siegrist, Claire-Anne; Pollard, Andrew J
Capsular polysaccharides (CPS) and lipopolysaccharides from bacteria are employed for the production of vaccines against human diseases. Initial development of CPS as a vaccine was followed by the development and introduction of conjugate polysaccharide-protein vaccines. The principles leading to both developments are reviewed.
Santana, Violeta Fernández; Balbin, Yury Valdés; Calderón, Janoi Chang; Icart, Luis Peña; Verez-Bencomo, Vicente
Influenza vaccine development is reviewed as an example of ongoing translational research, which is moving fundamental advances in biology into useful products. The types of new influenza vaccines span the gamut of modern biology research and include new methods of vaccine production (tissue culture compared with egg-produced vaccine). New vaccines being studied include recombinant proteins, polynucleotide vaccines, conjugate vaccines, peptides,
R B Belshe
Patients with B cell chronic lymphocytic leukemia (B-CLL) have decreased capacity to mount relevant antibody responses upon immunization, and development of hypogammaglobulinemia is part of the natural history of the disease. We investigated the influence of histamine type-2 (H2) receptor blockade by ranitidine on the in vivo antibody production in B-CLL patients following vaccination. Anti-polysaccharide antibodies in B-CLL patients, vaccinated with a tetanus-toxoid conjugated vaccine against Haemophilus influenzae type-B (Hib), reached long-term protective levels in more than 90% of B-CLL patients randomized to ranitidine treatment, as compared to 43% of the untreated patients (P = 0.024). No difference in the response to vaccination against influenza virus types A and B protein could be detected between the two groups. Plasma histamine levels were 2-fold to 20-fold higher in 23 out of 31 B-CLL patients, compared to normal controls, and these levels showed a significant positive correlation to disease duration. These findings indicate the possibility of improving in vivo antibody production against a highly relevant pathogen in B-CLL patients by histamine type-2 receptor blockade, and the combined finding of an immune-stimulatory effect of ranitidine and increased plasma histamine levels, strongly suggests the involvement of histamine in the pathogenesis of B-CLL immunodeficiency. PMID:7475282
Jurlander, J; de Nully Brown, P; Skov, P S; Henrichsen, J; Heron, I; Obel, N; Mortensen, B T; Hansen, M M; Geisler, C H; Nielsen, H J
This study quantifies the impact of Heptavalent-Pneumococcal Conjugate Vaccine (PCV7) in Panama on indigenous children younger than 5 years old, based on clinical pneumonia cases. This study demonstrates a significant 41.2% reduction in hospitalizations and 38.6% reduction in referrals for pneumonia following the introduction of PCV7. Burden of disease from pneumonia appears reduced in the ?12-month- and 13-to-24-month-old groups. PMID:23762081
Nieto Guevara, Javier; Daza, Carlos; Smith, Rebecca
Neisseria meningitidis is a major cause of invasive bacterial infections worldwide. For this reason, efforts to control the disease have been directed at optimizing meningococcal vaccines and implementing appropriate vaccination policies. In the past, plain polysaccharide vaccines containing purified capsular polysaccharides A, C, Y and W135 were developed, but failed to protect infants, who are at greatest risk. Experience with the conjugate Haemophilus vaccine suggested that this approach might well empower meningococcal vaccines. Thus, a very efficacious vaccine against serogroup C Neisseria meningitidis was optimized and has been widely used in developed nations since 1999. On the basis of epidemiological changes in the circulation of pathogenic serogroups in the United States, a quadrivalent conjugate vaccine against A, C, Y and W135 serogroups (Menactra™) has been developed and was approved by the US FDA (Food and Drug Administration) in 2005. Recently, another tetravalent conjugate meningococcal vaccine (Menveo™) has been licensed and made available in the United States of America and in the European Union. Finally, in response to large epidemics caused by serogroup A meningococcus in Africa, a new, safe, immunogenic and affordable vaccine has been developed. This review highlights the evolution of conjugate meningococcal vaccines in general and discusses how this kind of vaccine can contribute to preventing meningococcal disease.
Background Streptococcus pneumoniae remains a major cause of childhood morbidity and mortality worldwide. Nasopharyngeal colonization plays an important role in the development and transmission of pneumococcal diseases, and infants and young children are considered to be the main reservoir of this pathogen. The aim of this study was to evaluate the rates and characteristics associated with nasopharyngeal carriage, the distribution of serotypes and the antimicrobial resistance profiles of Streptococcus pneumoniae among children in a large metropolitan area in Brazil before the introduction of the 10-valent pneumococcal conjugate vaccine. Methods Between March and June 2010, nasopharyngeal swabs were collected from 242 children aged <6 years attending one day care center and the emergency room of a pediatric hospital. Pneumococcal isolates were identified by conventional methods and serotypes were determined by a sequential multiplex PCR assay and/or the Quellung reaction. The antimicrobial susceptibilities of the pneumococci were assessed by the disk diffusion method. MICs for erythromycin and penicillin were also performed. Erythromycin resistance genes were investigated by PCR. Results The overall colonization rate was 49.2% and it was considerably higher among children in the day care center. Pneumococcal carriage was more common among day care attenders and cohabitants with young siblings. The most prevalent serotypes were 6B, 19F, 6A, 14, 15C and 23F, which accounted for 61.2% of the isolates. All isolates were susceptible to clindamycin, levofloxacin, rifampicin and vancomycin. The highest rate of non-susceptibility was observed for sulphamethoxazole-trimethoprim (51.2%). Penicillin non-susceptible pneumococci (PNSP) accounted for 27.3% of the isolates (MICs of 0.12-4 ?g/ml). Penicillin non-susceptibility was strongly associated with serotypes 14 and 23F. Hospital attendance and the presence of respiratory or general symptoms were frequently associated with PNSP carriage. The two erythromycin-resistant isolates (MICs of 2 and 4 ?g/ml) belonged to serotype 6A, presented the M phenotype and harbored the mef(A/E) gene. Conclusions Correlations between serotypes, settings and penicillin non-susceptibility were observed. Serotypes coverage projected for the 10-valent pneumococcal conjugate vaccine was low (45.5%), but pointed out the potential reduction of PNSP nasopharyngeal colonization by nearly 20%.