Therapeutic immunisation plus cytokine and hormone therapy improves CD4 T-cell counts,restores anti-HIV-1 responses and reduces immune activation in treated chronic HIV-1 infection

BackgroundThis randomised, open label, phase I, immunotherapeutic study investigated the effects of interleukin (IL)-2, granulocyte-macrophage colony-stimulating factor (GM-CSF), recombinant human growth hormone (rhGH), and therapeutic immunisation (a Clade B DNA vaccine) on combination antiretroviral therapy (cART)-treated HIV-1-infected individuals, with the objective to reverse residual T-cell dysfunction.MethodsTwelve HIV-1⁺ patients on suppressive cART with baseline CD4 T-cell counts >400 cells/mm³ blood were randomised into one of three groups: (1) vaccine, IL-2, GM-CSF and rhGH (n = 3); (2) vaccine alone (n = 4); or (3) IL-2, GM-CSF and rhGH (n = 5). Samples were collected at weeks 0, 1, 2, 4, 6, 8, 12, 16, 24 and 48. Interferon (IFN)-γ, IL-2, IL-4 and perforin ELISpot assays performed at each time point quantified functional responses to Gag p17/p24, Nef, Rev, and Tat peptides; and detailed T-cell immunophenotyping was undertaken by flow cytometry. Proviral DNA was also measured.ResultsMedian baseline CD4 T-cell count was 757 cells/mm³ (interquartile range [IQR] 567–886 cells/mm³), median age 48 years (IQR 42–51 years), and plasma HIV-1-RNA <50 copies/ml for all subjects. Patients who received vaccine plus IL-2, GM-CSF and rhGH (group 1) showed the most marked changes. Assessing mean changes from baseline to week 48 revealed significantly elevated numbers of CD4 T cells (p = 0.0083) and improved CD4/CD8 T-cell ratios (p = 0.0033). This was accompanied by a significant reduction in expression of CD38 on CD4 T cells (p = 0.0194), significantly increased IFN-γ and IL-2 production in response to Gag (p = 0.0122) and elevated IFN-γ production in response to Tat (p = 0.041) at week 48 compared to baseline. Subjects in all treatment groups showed significantly reduced PD-1 expression at week 48 compared to baseline, with some reductions in proviral DNA.ConclusionsMultifarious immunotherapeutic approaches in the context of fully suppressive cART further reduce immune activation, and improve both CD4 T-lymphocyte counts and HIV-1-specific T-cell responses (NCT01130376).     

Impact of polymorphisms in the HCP5 and HLA-C,and ZNRD1 genes on HIV viral load

AIMSSingle nucleotide polymorphisms (SNPs) in the human leucocyte antigen (HLA) complex P5 (HCP5), HLA-C, and near the zinc ribbon domain containing 1 (ZNRD1) have been shown to influence viral load (VL) set point in HIV-infected individuals with a known seroconversion onset. We aimed to determine the influence of HCP5 rs2395029, HLA-C rs9264942, and ZNRD1 rs3869068 on VL in antiretroviral-naïve individuals and on time to the first VL < 51 copies/ml and on CD4⁺ T-cell recovery after initiation of combination antiretroviral therapy (cART).Material and methodsWe genotyped the rs2395029 (A > C), rs9264942 (T > C), and rs3869068 (C > T) SNPs in 1897 Caucasians from The Danish HIV Cohort Study — a prospective, nationwide, population-based study of HIV-infected individuals in Denmark. General linear models evaluated the effect of SNPs on VL in antiretroviral-naïve individuals 0–18 months after diagnosis and on CD4⁺ T-cell recovery during cART. Cox proportional hazard regression analysis assessed the association with time to first VL < 51 copies/ml. All models were assuming additive genetic effects.ResultsThe rs2395029, rs9264942, and rs3869068 minor alleles were associated with lower VL in antiretroviral-naïve individuals (rs2395029: [mean VL (copies/ml)], A/A: 70,795 [61,660–79,433], A/C: 33,884 [19,498–58,884], P = 0.002; rs9264942: TT: 81,283 [67,608–97,724], T/C: 63,096 [54,954–75,858], CC: 38,905 [25,119–58,884], P < 0.0001; rs3869068, CC: 72,444 [63,096–83,176], C/T: 45,709 [33,113–64,565], TT: 58,884 [20,417–169,824], P = 0.01). Moreover, the C-alleles of rs2395029 and rs9264942 were associated with shorter time to VL < 51 copies/ml: (HR [95% confidence interval], 1.67 [1.09–1.72], P = 0.008; 1.16 [1.06–1.28], P = 0.002; 1.30 [1.08–1.53], P = 0.005, respectively, adjusted for last VL before cART). None of the SNPs predicted CD4⁺ T-cell recovery during cART.ConclusionsThe minor alleles of rs2395029, rs9264942, and rs3689068 associate with lower VL among antiretroviral-naïve individuals and with shorter time to first VL < 51 copies/ml during cART even after adjustment for VL before cART.     

Hepatitis B vaccination uptake and correlates of serologic response among HIV-infected and uninfected men who have sex with men (MSM) in Bangkok,Thailand

BackgroundVaccination against hepatitis B virus (HBV) is recommended for all HBV-susceptible men who have sex with men (MSM). There is limited information on correlates of immunity to HBV vaccination in this group. We present serologic response rates to hepatitis B vaccine and identify factors associated with impaired response among HIV-uninfected and HIV-infected Thai MSM.MethodologyHBV-susceptible volunteers were offered hepatitis B vaccination at months zero, one, and six. We measured baseline (pre-vaccination) total serum IgG and IgG subclasses (all participants), baseline CD4 count, and plasma HIV-1 viral load (PVL) (HIV+ participants). HBV serologies were retested at 12 months. Serologic responses were compared between all groups in men receiving three vaccine doses.Results511/651 HIV-negative and 64/84 HIV-positive participants completed the three-dose series. Response rates in HIV-uninfected and -infected participants were 90.1% vs. 50.0% (p < 0.0001). Median pre-vaccination IgG was higher among non-responders than responders overall (1238.9.0 vs. 1057.0 mg/dL, p = 0.003) and among HIV-infected participants (1534.0 vs. 1244.5 mg/dL, p = 0.005), but not significantly among HIV-uninfected participants (1105.5 vs. 1054.3 mg/dL, p = 0.96). Pre-vaccination IgG1 and IgG3 levels were higher among HIV-positive than HIV-negative participants (median 866.0 vs. 520.3, and 105.8 vs. 83.1 mg/dL, respectively, p < 0.0001). Among HIV-infected participants, median CD4 count in non-responders was 378 cells/μL vs. 431 cells/μL in responders (p = 0.20). Median PVL in non-responders was 64,800 copies/mL vs. 15500 copies/mL in responders (p = 0.04). Participants with pre-vaccination plasma IgG >1550 mg/dL and PVL >10,000 copies/mL were almost always non-responsive (p < 0.01).ConclusionsHIV infection was associated with poor vaccine responses. High plasma viral load, elevated pre-vaccination total serum IgG and elevated pre-vaccination IgG1 are associated with poorer response to vaccination among HIV-infected MSM. In this group, the combination of high PVL and pre-vaccination total IgG is highly predictive of vaccine failure.     

Pneumococcal vaccination in patients with systemic lupus erythematosus: A multicenter placebo-controlled randomized double-blind study

BackgroundInvasive pneumococcal disease and respiratory tract infections are both frequent and severe in patients with systemic lupus erythematosus (SLE). This study aimed to compare the immunological efficacy and safety of pneumococcal vaccination with the 23-valent polysaccharide (PPS) vaccine alone to a sequential immunization with the 7-valent pneumococcal conjugate (PnCj) vaccine followed by PPS in patients with SLE and stable diseaase.MethodsMulticenter randomized placebo-controlled double-blind trial: PPS vaccine alone (placebo-PPS group) or PnCj vaccine followed by PPS vaccine (PnCj-PPS group) 24 weeks later. The primary endpoint was the rate of responders at week 28 to at least 5 of the 7 serotypes (4, 6B, 9V, 14, 18C, 19F and 23F) shared by both PPS and PnCj. Pneumococcal IgG antibodies’ opsonophagocytic activity (OPA) were also assessed.ResultsTwenty-five patients in the placebo-PPS group and 17 in the PnCj-PPS group were included in a modified intention-to-treat analysis. The primary endpoint was reached in 72% (18/25) in the placebo-PPS and 76% (13/17) in the PnCj-PPS group (p = 0.75). There was no difference in the rates of responders with OPA. At week 52, 13/18 (72%) patients in the placebo-PPS group and 10/13 (77%) patients in the PnCj-PPS group (p = 0.77) that met the primary endpoint at week 28 were still responders to ≥5/7 serotypes shared by both PPS and PnCj vaccines. Nine SLE flares were reported in 6 patients (4 in the placebo-PPS and 2 in the PnCj-PPS groups respectively, p = 0.70).ConclusionSequential administration of PnCj vaccine followed by PPS vaccine is safe and shows short-term immunological efficacy in patients with SLE but was not superior to the PPS vaccine alone.Trial registration: www.clinicaltrials.gov, NCT NCT00611663     

Replication-defective lymphocytic choriomeningitis virus vectors expressing guinea pig cytomegalovirus gB and pp65 homologs are protective against congenital guinea pig cytomegalovirus infection

BackgroundCongenital cytomegalovirus infection can be life-threatening and often results in significant developmental deficits and/or hearing loss. Thus, there is a critical need for an effective anti-CMV vaccine.ObjectiveTo determine the efficacy of replication-defective lymphocytic choriomeningitis virus (rLCMV) vectors expressing the guinea pig CMV (GPCMV) antigens, gB and pp65, in the guinea pig model of congenital CMV infection.MethodsFemale Hartley strain guinea pigs were divided into three groups: Buffer control group (n = 9), rLCMV-gB group (n = 11), and rLCMV-pp65 (n = 11). The vaccines were administered three times IM at 1.54 × 10⁶ FFU per dose at 21-day intervals. At two weeks after vaccination, the female guinea pigs underwent breeding. Pregnant guinea pigs were challenged SQ at ∼45–55 days of gestation with 1 × 10⁵ PFU of GPCMV. Viremia in the dams, pup survival, weights of pups at delivery, and viral load in both dam and pup tissues were determined.ResultsPup survival was significantly increased in the LCMV-gB vaccine group. There was 23% pup mortality in the gB vaccine group (p = 0.044) and 26% pup mortality in the pp65 vaccine group (p = 0.054) compared to 49% control pup mortality. The gB vaccine induced high levels of gB binding and detectable neutralizing antibodies, reduced dam viremia, and significantly reduced viral load in dam tissues compared to control dams (p < 0.03). Reduced viral load and transmission in pups born to gB-vaccinated dams was observed compared to pups from pp65-vaccinated or control dams.ConclusionsThe rLCMV-gB vaccine significantly improved pup survival and also increased pup weights and gestation time. The gB vaccine was also more effective at decreasing viral load in dams and pups and limiting congenital transmission. Thus, rLCMV vectors that express CMV antigens may be an effective vaccine strategy for congenital CMV infection.     

Short and long-term immunogenicity and safety following the 23-valent polysaccharide pneumococcal vaccine in juvenile idiopathic arthritis patients under conventional DMARDs with or without anti-TNF therapy

ObjectivesTo assess immunogenicity and safety of the 23-valent polysaccharide pneumococcal vaccine (PPV23) in juvenile idiopathic arthritis (JIA) patients under conventional DMARDs with or without anti-TNF therapy. The influences of demographic data, disease activity and treatment on immune response and the potential deleterious effects of vaccine on disease itself were also evaluated.Methods17 JIA patients immediately pre-etanercept (Group 1) and 10 JIA patients on stable dose of methotrexate (Group 2) received one dose of PPV23. All patients were evaluated pre-vaccination, 2 months and 12 months post-vaccination for seven pneumoccocal serotypes. Serology was performed by enzyme immunoassay and the immunogenicity endpoints included seroprotection (SP), seroconversion (SP) and geometric mean concentration of antibodies(GMC). Clinical and laboratorial parameters of JIA were evaluated before and after vaccination.ResultsGroups 1 and 2 were comparable regarding age, gender, disease duration and other DMARDs use (p > 0.05). Pre-immunization SP and GMC were alike in patients with and without anti-TNF therapy (p > 0.05). The frequencies of patients achieving adequate vaccine response (seroconversion in ≥50% of all serotypes) at 2 months (53 vs. 30%, p = 0.424) and 12 months (36 vs. 40%, p = 1.0) were similar in JIA patients with and without anti-TNF therapy. Further comparison of patients with and without adequate response at 2 months revealed no influence of demographic, clinical and laboratorial JIA parameters (p > 0.05). Serious adverse events were not observed.ConclusionsAnti-TNF therapy in JIA patients does not seem to have an additional deleterious effect on short/long-term PPV23 immunogenicity compared to MTX alone and no influence on disease parameters was observed with this vaccine.     

HIV viral suppression results in higher antibody responses in HIV-positive women vaccinated with the quadrivalent human papillomavirus vaccine

ObjectiveTo evaluate the immunogenicity and safety of the quadrivalent HPV (qHPV) vaccine in HIV-positive women over 24 months.DesignBetween November 2008 and December 2012, 372 women aged 15 and older were enrolled from 14 Canadian HIV outpatient clinics in an open label cohort study. The qHPV vaccine (0.5 mL) was administered intramuscularly at months 0, 2 and 6. The primary study endpoint was seroconversion to any of the HPV types targeted by the qHPV vaccine. Antibody levels were measured at 0, 2, 7, 12, 18, and 24 months. Adverse events were recorded throughout.ResultsOf 372 participants enrolled, 310 (83%) received at least one dose of the qHPV vaccine and 277 (74%) received all three doses. Ninety-five percent (293/308) were seronegative for at least one vaccine type at baseline. The median age was 38 years (IQR 32–45, range 15–66), 36% were white, 44% black and 13% were of Indigenous origin. Seventy-two percent of participants had a suppressed HIV viral load (VL < 40 c/ml) at baseline, with a median CD4 count of 510 cells/mm³ (376–695). Month 7 HPV type-specific seroconversion rates were 99.0%, 98.7%, 98.1% and 93.6% for HPV types 6, 11, 16 and 18 respectively in the per-protocol population. Participants with suppressed HIV VL at first vaccine had a 1.74–3.05 fold higher peak antibody response compared to those without (p from 0.006 to <0.0001).ConclusionsThis study is the first to examine the qHPV vaccine in HIV-positive women out to 24 months and the first to include HIV-positive women through to age 66. The qHPV vaccine was well tolerated, and highly immunogenic. As women with suppressed viral load had higher antibody responses, planning HPV vaccination to occur when persons are virologically suppressed would be optimal for maximizing immune response. Findings provide strong evidence that older HIV-positive women can still benefit from HPV vaccination.Clinical trial registration: http://www.isrctn.com/ISRCTN33674451     

Factors related to vaccine uptake by young adult women in the catch-up phase of the National HPV Vaccination Program in Australia: Results from an observational study

BackgroundAustralia commenced a publically-funded, National Human Papillomavirus (HPV) Vaccination Program in 2007 with a two year catch-up phase for females aged 12–26 years.ObjectiveTo identify the factors associated with the uptake of the HPV vaccine (which has a recommended 3-dose schedule in Australia) by young adult women vaccinated by general practitioners and community-based programs within the catch-up phase.Methods1139 women who were eligible to receive the free HPV vaccine during the catch-up period were recruited in 2008–2009 (age 20–29 years at recruitment), in New South Wales, after having a normal (negative) cervical smear result recorded on the NSW Pap Test Register. Participants completed a self-administered questionnaire providing information on vaccination status, and sociodemographic and other factors.ResultsOverall, 880 (77%) women reported receiving ≥1 dose of the vaccine and 777 women (68%) reported receiving ≥2 doses. In multivariable analysis (adjusting for the period for which each woman was eligible for free HPV vaccination), uptake of ≥1 dose of the vaccine was significantly associated with being born in Australia (p < 0.01), being single (p = 0.02), being nulliparous (p < 0.01), living in a higher socioeconomic status area (p-trend = 0.03), living in more remote areas (p = 0.03), drinking alcohol (p < 0.01) and using hormonal contraceptives (p < 0.01). Although vaccinated women were more likely to have fewer sexual partners than unvaccinated women (p-trend = 0.02), they were also more likely to report a prior sexually transmitted infection (STI) (p = 0.03). Similar factors were associated with receiving ≥2 doses.ConclusionsIn this group, women living in higher socioeconomic status areas were more likely to be vaccinated against HPV in the catch-up phase of the national program. Although vaccinated women tended to have fewer sexual partners, they also reported prior STIs, which may be a marker of increased risk of prior exposure to HPV. The findings of this study reinforce the continuing need to prioritise equitable delivery of vaccination to various population subgroups.     

Exploring evidence for behavioral risk compensation among participants in an HIV vaccine clinical trial

BackgroundHIV vaccine trial participants may engage in behavioral risk compensation due to a false sense of protection. We conducted an ancillary study of an HIV Vaccine Trials Network (HVTN) vaccine efficacy trial to explore risk compensation among trial participants compared to persons who were willing to participate but ineligible based on previous exposure to the Ad5 virus (Ad5+) across three timepoints.MethodsParticipants were drawn from the Atlanta, GA site of the HVTN 505 vaccine trial. From 2011–2013, all persons who met prescreening criteria for the clinical trial and presented for Ad5 antibody testing were invited to participate in the ancillary study. Data were collected from vaccine trial participants (n = 51) and Ad5+ participants (n = 60) via online surveys across three timepoints: baseline, T2 (after trial participants received 2/4 injections) and T3 (after trial participants received 4/4 injections). Data analyses assessed demographic, psychosocial, and behavioral differences at baseline and changes at each timepoint.ResultsAt baseline, Ad5+ participants were less likely to have some college education (p = 0.024) or health insurance (p = 0.008), and were more likely to want to participate in the vaccine trial “to feel safer having unprotected sex” (p = 0.005). Among vaccine trial participants, unprotected anal sex with a casual partner (p = 0.05), HIV transmission worry (p = 0.033), and perceived chance of getting HIV (p = 0.027), decreased across timepoints.ConclusionsStudy findings suggest that persons with previous exposure to Ad5 may be systematically different from their Ad5-negative peers. Unprotected anal sex with a casual partner significantly decreased among HIV vaccine trial participants, as did HIV worry and perceived chance of getting HIV. Findings did not support evidence of risk compensation among HIV vaccine trial participants compared to Ad5+ participants.     

Hepatitis B vaccine alone may be enough for preventing hepatitis B virus transmission in neonates of HBsAg (+)/HBeAg (−) mothers

Background and aimTo prospectively evaluate the efficacy of vaccine alone compared with vaccine plus HBIG for preventing HBV transmission in neonates of HBsAg (+)/HBeAg (−) mothers.MethodsCombined immunization is currently recommended for neonates of HBsAg (+) mothers in China. As a result, a randomized design is infeasible due to ethical reasons. In practice, Guangxi Zhuang Autonomous Region and Jiangsu Province implement vaccine alone and vaccine plus HBIG strategies for neonates born to HBsAg (+)/HBeAg (−) mothers, respectively. We alternatively enrolled neonates of HBsAg (+)/HBeAg (−) mothers from these two regions. Three doses of a recombinant yeast-derived hepatitis B vaccine were given at 0, 1 and 6 months with or without HBIG at birth.ResultsAt 7 months, sera were collected from 132 neonates in Guangxi Zhuang Autonomous Region and 752 neonates in Jiangsu Province. Baseline characteristics of both mothers and neonates were comparable in the two regions. No differences were revealed regarding the occurrence of perinatal HBV transmission with or without HBIG at birth [0.1% (1/752) vs. 0.0% (0/132), p = 1.000]. The anti-HBs response rates were 97.7% (129/132) and 98.5% (740/751) for the neonates with vaccine alone and with HBIG (p = 0.758), respectively. Vaccine alone induced a significantly higher anti-HBs GMC as compared to vaccine plus HBIG at 7 months of age (1555.3 mIU/mL vs. 654.9 mIU/mL, p < 0.0001). At 12 months of age, protective levels of anti-HBs remained in 97.4% (596/612) and 98.3% (118/120) of the neonates receiving and not receiving HBIG, respectively (p = 0.771). The neonates receiving combined prophylaxis had a markedly lower anti-HBs GMC (210.7 mIU/mL vs. 297.0 mIU/mL, p = 0.011). Horizontal HBV transmission occurred in none of the successfully immunized neonates for both compared groups at 12 months of age.ConclusionsVaccine alone may be enough for preventing HBV transmission in neonates of HBsAg (+)/HBeAg (−) mothers.     

Factors affecting the causality assessment of adverse events following immunisation in paediatric clinical trials: An online survey

BackgroundSerious adverse events (SAEs) in clinical trials require reporting within 24 h, including a judgment of whether the SAE was related to the investigational product(s). Such assessments are an important component of pharmacovigilance, however classification systems for assigning relatedness vary across study protocols. This on-line survey evaluated the consistency of SAE causality assessment among professionals with vaccine clinical trial experience.MethodsMembers of the clinical advisory forum of experts (CAFÉ), a Brighton Collaboration online-forum, were emailed a survey containing SAEs from hypothetical vaccine trials which they were asked to classify. Participants were randomised to either two classification options (related/not related to study immunisation) or three options (possibly/probably/unrelated). The clinical scenarios, were (i) leukaemia diagnosed 5 months post-immunisation with a live RSV vaccine, (ii) juvenile idiopathic arthritis (JIA) 3 months post-immunisation with a group A streptococcal vaccine, (iii) developmental delay diagnosed at age 10 months after infant capsular group B meningococcal vaccine, (iv) developmental delay diagnosed at age 10 months after maternal immunisation with a group B streptococcal vaccine.ResultsThere were 140 respondents (72 two options, 68 three options). Across all respondents, SAEs were considered related to study immunisation by 28% (leukaemia), 74% (JIA), 29% (developmental delay after infant immunisation) and 42% (developmental delay after maternal immunisation). Having only two options made respondents significantly less likely to classify the SAE as immunisation-related for two scenarios (JIA p = 0.0075; and maternal immunisation p = 0.045). Amongst study investigators (n = 43) this phenomenon was observed for three of the four scenarios: (JIA p = 0.0236; developmental delay following infant immunisation p = 0.0266; and developmental delay after maternal immunisation p = 0.0495).ConclusionsSAE causality assessment is inconsistent amongst study investigators and can be influenced by the classification systems available to them. There is a pressing need for SAE classification systems to be standardised across study protocols.     

Safety and immunogenicity of the novel H4:IC31 tuberculosis vaccine candidate in BCG-vaccinated adults: Two phase I dose escalation trials

BackgroundNovel vaccine strategies are required to provide protective immunity in tuberculosis (TB) and prevent development of active disease. We investigated the safety and immunogenicity of a novel TB vaccine candidate, H4:IC31 (AERAS-404) that is composed of a fusion protein of M. tuberculosis antigens Ag85B and TB10.4 combined with an IC31® adjuvant.MethodsBCG-vaccinated healthy subjects were immunized with various antigen (5, 15, 50, 150 μg) and adjuvant (0, 100, 500 nmol) doses of the H4:IC31 vaccine (n = 106) or placebo (n = 18) in two randomized, double-blind, placebo-controlled phase I studies conducted in a low TB endemic setting in Sweden and Finland. The subjects were followed for adverse events and CD4⁺ T cell responses.ResultsH4:IC31 vaccination was well tolerated with a safety profile consisting of mostly mild to moderate self-limited injection site pain, myalgia, arthralgia, fever and post-vaccination inflammatory reaction at the screening tuberculin skin test injection site. The H4:IC31 vaccine elicited antigen-specific CD4⁺ T cell proliferation and cytokine production that persisted 18 weeks after the last vaccination. CD4⁺ T cell expansion, IFN-γ production and multifunctional CD4⁺ Th1 responses were most prominent after two doses of H4:IC31 containing 5, 15, or 50 μg of H4 in combination with the 500 nmol IC31 adjuvant dose.ConclusionsThe novel TB vaccine candidate, H4:IC31, demonstrated an acceptable safety profile and was immunogenic, capable of triggering multifunctional CD4⁺ T cell responses in previously BCG-vaccinated healthy individuals. These dose-escalation trials provided evidence that the optimal antigen-adjuvant dose combinations are 5, 15, or 50 μg of H4 and 500 nmol of IC31.Trial registration: ClinicalTrials.gov, NCT02066428 and NCT02074956.     

A randomized clinical trial in adults and newborns in South Africa to compare the safety and immunogenicity of bacille Calmette-Guérin (BCG) vaccine administration via a disposable-syringe jet injector to conventional technique with needle and syringe

IntroductionIntradermal bacille Calmette-Guérin (BCG) vaccination by needle-free, disposable-syringe jet injectors (DSJI) is an alternative to the Mantoux method using needle and syringe (NS). We compared the safety and immunogenicity of BCG administration via the DSJI and NS techniques in adults and newborn infants at the South African Tuberculosis Vaccine Initiative (SATVI) research site in South Africa.MethodThirty adults and 66 newborn infants were randomized 1:1 to receive intradermal BCG vaccine (0.1 mL in adults; 0.05 mL in infants) via DSJI or NS. Wheal diameter (mm) and skin fluid deposition at the site of injection (SOI) were measured immediately post-vaccination. Adverse events and SOI reactogenicity data were collected 30 min and 1, 2, 4, and 12 weeks after vaccination for adults and at 30 min and 4, 10, and 14 weeks for infants. Blood was collected in infants at 10 and 14 weeks to assess BCG-specific T-cell immune responses.ResultsMore infant BCG vaccinations by DSJI deposited >5 μL fluid on the skin surface, compared to NS (49% versus 9%, p = 0.001). However, all 12 infant vaccinations that did not produce any SOI wheal occurred in the NS group (36%, p < 0.001). Median wheal diameter, in participants for which an SOI wheal formed, did not differ significantly between groups in infants (combined 3.0 mm IQR 2.0 to 4.0, p = 0.59) or in adults (combined 9.0 mm IQR 7.0 to 10.0, p = 0.13). Adverse events were similar between study arms. Proportion of participants with BCG scars after three months did not differ in adults (combined 97%, p = 0.67) or infants (combined 62%, p = 0.13). Frequencies of BCG-specific clusters of differentiation 4 (CD4) and clusters of differentiation 8 (CD8) T-cells co-expressing IFN-γ, TNF-α, IL-2, and/or IL-17 were not different in the DSJI and NS groups.ConclusionBCG vaccination of newborn infants via DSJI was more likely to deliver an appropriate intradermal wheal at the SOI as compared to NS, despite leaving more fluid on the surface of the skin. Safety, reactogenicity, and antigen-specific T-cell immune responses did not differ between DSJI and NS techniques.     

Variation of growth in the production of the BCG vaccine and the association with the immune response. An observational study within a randomised trial

IntroductionBacille Calmette–Guérin (BCG) vaccine has beneficial non-specific effects on overall survival. After BCG vaccination, positive PPD response and scar formation are associated with increased survival. During a trial randomising low-birth-weight neonates to BCG at birth or the usual delayed BCG, the manufacturer of the BCG vaccine experienced a period with relatively slow growth rate of the BCG. We investigated the association between growth rate of BCG when manufacturing the vaccine and its capability to induce immune responses in vivo and in vitro.Methods1633 neonates were randomised to BCG at birth and examined for scar at 12 months; a subgroup was tested for PPD response at 2 and 6 months. The BCG batches from the Slow growth period were compared with the precedent and subsequent Normal growth batches with regard to prevalence and size of BCG scar and PPD response. We also tested the effect of batches on in vitro cytokine responses.ResultsAt 12 months, the Slow growth batches were associated with higher BCG scar prevalence (98.2%) than the precedent batches (92.3%, p = 0.01) but the prevalence remained high after return to normal growth (98.8%, p = 0.52). The Slow growth batches were associated with larger scar size (5.0 mm) than precedent (4.4 mm, p < 0.01) and subsequent batches (4.8 mm, p = 0.03). Compared with Normal growth batches, the Slow growth batches were associated with a higher prevalence of positive PPD responses, and among PPD positive children, a larger PPD reaction (geometric mean ratio: 1.40 (1.20–1.63)) at 2 months. In response to secondary heterologous stimulation, monocytes primed with Slow growth batches induced higher IL-6 (p = 0.03) and TNF-α responses (p = 0.03) compared with Normal growth batches.ConclusionThe study indicates that variations in the production of BCG vaccine may influence important immunological effects of the vaccine.Trial registrationclinicaltrials.gov (NCT00625482).     

Immune response in infants after universal high-dose hepatitis B vaccination: A community-based study in Beijing,China

BackgroundVaccination of infants beginning at birth is recommended to prevent Hepatitis B virus (HBV) infection in China. Compared to 5 μg/dose vaccine administered in other regions in China, a three-dose HB recombinant yeast vaccine at 10 μg/dose has been administered for infants within 24 h after birth, 1 month and 6 months of age in Beijing since 2006. In a community-based retrospective cohort study, factors influencing immunologic vaccine response were evaluated.MethodsA total of 3670 infants who completed a 3-dose 10 μg recombinant HB vaccine regimen and born to hepatitis B antigen negative mothers were included. The effect on anti-HBs titers of maternal nutrient status, infants’ birth condition, growth factors, timeliness of vaccination, dosing interval and the interval until post-vaccination serologic testing (PVST) were evaluated.ResultsA total of 3666 infants with no markers of HBV infection were included in analysis. The mean anti-HB titers were 1767.17 mIU/ml. Only 16.9% of the infants completed their PVST within 30–59 days after the final dose of vaccination. Multivariate linear regression analysis showed that delay in PVST (β = −0.097, p < 0.0001) and maternal folic acid supplementation (β = 0.067, p = 0.002) were associated with log-transformed anti-HB titers. Also a trend toward significant association was observed between the calcium supplementation of infants and log-transformed anti-HBs titers (β = 0.062, p = 0.057). Longer interval between dose 2 and dose 3 was not observed to increase the anti-HB titers after cofactors adjustment.ConclusionsOur findings illustrate the importance of timing of PVST to avoid unnecessary revaccination. Multi-center large cohort studies should verify the effect and magnitude of folate and calcium supplementation on HB vaccine response.     

Vaccine Adjuvant Systems containing monophosphoryl lipid A and QS-21 induce strong humoral and cellular immune responses against hepatitis B surface antigen which persist for at least 4 years after vaccination

BackgroundRecombinant hepatitis B surface antigen (HBsAg) was used as a model antigen to evaluate persistence of cellular and humoral immune responses when formulated with three different Adjuvant Systems containing 3-O-desacyl-4′-monophosphoryl lipid A (MPL) and QS-21, in an oil-in-water emulsion (AS02_B and AS02_V), or with liposomes (AS01_B).MethodsThis is an open, 4-year follow-up of a previous randomised, double-blind study. Healthy subjects aged 18–40 years received three vaccine doses on a month 0, 1, 10 schedule and were initially followed for 18 months. A total of 93 subjects (AS02_B: n = 30; AS02_V: n = 28; AS01_B: n = 35) were enrolled in this follow-up and had an additional blood sample taken at Year 4 (NCT02153320). The primary endpoint was the frequency of HBsAg-specific CD4⁺ and CD8⁺ T-cells expressing cytokines upon short-term in vitro stimulation of peripheral blood mononuclear cells with HBsAg-derived peptides. Secondary endpoints were anti-HBs antibody titres and frequency of HBsAg-specific memory B-cells.ResultsA strong and persistent specific CD4⁺ T-cell response was observed at Year 4 in all groups. HBsAg-specific CD4⁺ T-cells expressed mainly CD40L and IL-2, and to a lesser extent TNF-α and IFN-γ. HBsAg-specific CD8⁺ T-cells were not detected in any group. A high, persistent HBsAg-specific humoral immune response was observed in all groups, with all subjects seroprotected (antibody titre ≥10 mIU/mL) at Year 4. The geometric mean antibody titre at Year 4 was above 100,000 mIU/mL in all groups. A strong memory B-cell response was observed post-dose 2, which tended to increase post-dose 3 and persisted at Year 4 in all groups.ConclusionThe MPL/QS-21/HBsAg vaccine formulations induced persistent immune responses up to 4 years after first vaccination. These Adjuvant Systems offer potential for combination with recombinant, synthetic or highly purified subunit vaccines, particularly for vaccination against challenging diseases, or in specific populations, although additional studies are needed.     

Decrease in circulating CD25hiFoxp3+ regulatory T cells following vaccination with the candidate malaria vaccine RTS,S

Regulatory T (Treg) cells have been shown in some cases to limit vaccine-specific immune responses and impact efficacy. Very little is known about the regulatory responses to the leading malaria vaccine candidate, RTS,S. The goal of this study was to begin to characterize the regulatory responses to the RTS,S vaccine. Using multi-parameter flow cytometry, we examined responses in 13 malaria naïve adult volunteers who received 2 doses of RTS,S given eight weeks apart. Five of these volunteers had previously received 3 doses of a candidate DNA-CSP vaccine, with the final dose given approximately one year prior to the first dose of the RTS,S vaccine.We found that the frequency of CD25^hiFoxp3⁺ Treg cells decreased following administration of RTS,S (p = 0.0195), with no differences based on vaccine regimen. There was a concomitant decrease in CTLA-4 expression on CD25^hiFoxp3⁺ Treg cells (p = 0.0093) and PD-1 levels on CD8⁺ T cells (p = 0.0002). Additionally, the frequency of anergic CTLA-4⁺CCR7⁺ T cells decreased following vaccination. An inverse correlation was observed between the frequency of Plasmodium falciparum circumsporozoite protein (PfCSP)-specific IFN-γ and PfCSP-specific IL-10, as well as an inverse correlation between IL-10 induced by Hepatitis B surface antigen, the carrier of RTS,S, and PfCSP-specific IFN-γ, suggesting that immunity against the vaccine backbone could impact vaccine immunogenicity. These results have implications for future malaria vaccine design.     

Baseline serum interleukin-6 to interleukin-2 ratio is associated with the response to seasonal trivalent influenza vaccine in solid organ transplant recipients

BackgroundThe analysis of pre- and post-vaccination B-cell-associated cytokines might be useful in predicting the immunogenicity of seasonal trivalent influenza vaccine (TIV) in solid organ transplant (SOT) recipients.MethodsWe performed a subanalysis of a clinical trial that compared the safety and efficacy of high-dose intradermal (ID) versus intramuscular (IM) TIV in SOT recipients. Serum levels of selected cytokines (interferon [IFN]-γ, interleukin [IL]-2, IL-4, IL-5, IL-6, IL-12 and IL-21, and tumor necrosis factor [TNF]-α) were measured pre- and one month post-vaccination in 155 patients (with 84 and 71 receiving the ID and IM vaccines, respectively). Cytokine profiles were compared according to vaccine response (seroconversion [≥4-fold increase in hemagglutination inhibition antibody titers] to ≥1 influenza vaccine antigen).ResultsMean baseline IL-6 levels were higher (1.20 versus 0.65 pg/mL; P-value = 0.021) and IL-2 levels were lower (0.01 versus 0.50 pg/mL; P-value = 0.051) in patients achieving vaccine response. After adjusting for clinical variables, baseline IL-6/IL-2 ratio remained predictive of vaccine response (odds ratio per 10-unit increment: 1.06; 95% confidence interval: 1.02–1.10; P-value = 0.002). Vaccination induced an increase in TNF-α (P-value <0.0001) and a decrease in IL-5 levels (P-value = 0.0007). There were no significant differences in cytokine kinetics between vaccine responders and non-responders. Mean baseline TNF-α levels were higher in patients experiencing moderate-to-severe adverse events after vaccination (1.93 versus 1.72 pg/mL; P-value = 0.009).ConclusionsBaseline serum IL-6 and IL-2 levels, two cytokines that modulate the role of CD4⁺ T follicular helper cells and the terminal differentiation of B-cells, predict vaccine response in SOT recipients.     

Improving immunity to Haemophilus influenzae in children with chronic suppurative lung disease

BackgroundEndobronchial infections related to non-typeable Haemophilus influenzae (NTHi) are common in children and adults with suppurative airway disease such as bronchiectasis and COPD. Impaired cell mediated immune responses to NTHi have been described in these patients. Currently there are no interventions known to correct the deficiency in cell mediated immune responses to NTHi. The aim of this study was to determine if receipt of a conjugate vaccine containing protein D from H. influenzae is associated with improvement in NTHi-specific cytokine responses in children with chronic suppurative lung disease.MethodsBlood mononuclear cells from 107 young children with chronic suppurative lung disease and 32 healthy control children were stimulated in vitro with NTHi. We compared the cytokine production of stimulated mononuclear cells from children who had received the pneumococcal H. influenzae protein D conjugate vaccine with cells from children who received pneumococcal vaccines without protein D. Protein D-specific IgG1 was quantified in plasma.ResultsChildren with chronic suppurative lung disease who received ≥3 doses of the protein D conjugate vaccine produced significantly more IFNγ than children who received the alternative vaccines without protein D (median 939 versus 338 pg/ml; p = 0.007). Importantly, the amount of IFNγ produced by those vaccinated with the conjugate vaccine approached the levels observed in cells from healthy children. The conjugate vaccine was also associated with small but significant increases in IL-13 (p < 0.001) and IL-5 (p = 0.007). Protein D-specific IgG1 levels correlated with the number of PHiD-CV doses (p = 0.02).ConclusionVaccination with PHiD-CV is associated with improvements in NTHi-specific cell-mediated and humoral immune responses in children with chronic suppurative lung disease.     

Immune response to pneumococcal conjugate vaccine in patients with systemic vasculitis receiving standard of care therapy

AimTo study the effect of standard of care therapy on antibody response and functionality following immunization with 13-valent pneumococcal conjugate vaccine (PCV13) in patients with primary systemic vasculitis compared to healthy controls.Methods49 patients with vasculitis and 49 controls received a single dose (0.5 ml) PCV13 intramuscularly. Ongoing treatments: azathioprine (AZA; n = 11), cyclophosphamide (CYC; n = 6), methotrexate (MTX; n = 9), rituximab (n = 3); anti-TNF (n = 2), mycophenolate mofetil (n = 2), prednisolone alone (n = 15) and no active treatment (n = 2). Specific antibody concentrations for serotypes 6B and 23F were determined using ELISA and opsonophagocytic activity (OPA) assay (23F) was performed, on serum samples taken immediately before and 4–6 weeks after vaccination. Proportion of individuals with putative protective antibody concentration (≥1.0 µg/mL) and positive antibody response (≥2-fold increase from prevaccination concentration) for both serotypes were calculated and groups were compared.ResultsAt baseline, 6 patients (12%) and 12 controls (24%) had protective antibody levels for both serotypes. After vaccination, antibodies increased for both serotypes in patients and controls (p < 0.001), 32 patients (65%) and 35 controls (71%) reached protective level for 6B, and 32 patients (65%) and 37 controls (76%) for 23 F. Compared to controls, patients had lower prevaccination geometric mean concentration (23F, p = 0.01) and a numerical trend towards lower prevaccination level (6B) and postvaccination levels (both serotypes). Patients with prednisolone alone had lower prevaccination OPA (p < 0.01) compared to controls. OPA increased after vaccination in both patients and controls (p < 0.001), but improvement was better in controls (p = 0.001). AZA, CYC or MTX, but not prednisolone alone, tended towards a lower proportion of patients reaching protective antibody levels (p = 0.06), compared to controls.ConclusionsPneumococcal conjugate vaccine was safe and immunogenic in patients with established vasculitis. Treatment with DMARDs, mostly AZA, CYC and MTX but not systemic prednisolone may impair antibody response.Trial registration. ClinicalTrials.gov Identifier: NCT02240888. Registered 4 September, 2014