Metabolic Phenotypes of Response to Vaccination in Humans.

Herpes zoster (shingles) causes significant morbidity in immune compromised hosts and older adults. Whereas a vaccine is available for prevention of shingles, its efficacy declines with age. To help to understand the mechanisms driving vaccinal responses, we constructed a multiscale, multifactorial response network (MMRN) of immunity in healthy young and older adults immunized with the live attenuated shingles vaccine Zostavax. Vaccination induces robust antigen-specific antibody, plasmablasts, and CD4+ T cells yet limited CD8+ T cell and antiviral responses. The MMRN reveals striking associations between orthogonal datasets, such as transcriptomic and metabolomics signatures, cell populations, and cytokine levels, and identifies immune and metabolic correlates of vaccine immunity. Networks associated with inositol phosphate, glycerophospholipids, and sterol metabolism are tightly coupled with immunity. Critically, the sterol regulatory binding protein 1 and its targets are key integrators of antibody and T follicular cell responses. Our approach is broadly applicable to study human immunity and can help to identify predictors of efficacy as well as mechanisms controlling immunity to vaccination.

Detection of Viral RNA and DNA and Immune Response Following Administration of Live Attenuated Measles and Varicella Vaccines in Children with Chronic Liver Disease.

Infections preventable by live virus vaccines are surging in the setting of decreased herd immunity. Many children with chronic liver diseases (CLD) are unimmunized and at increased risk for infection due to guidelines recommending against live vaccines within 4 weeks pre-transplant. This prospective study of 21 children with CLD and 13 healthy controls defined the timing of measles and varicella RNA- and DNA-emia following vaccination and compared immune responses to measles and varicella vaccines in both groups. Measles RNA and varicella DNA real-time PCR were measured weekly following vaccination; measles RNA was undetectable in all by 14 days post-vaccination, but varicella DNA, which can be managed with antivirals, was detected in one child in the CLD group at 21 days and one control at 28 days post-vaccination. Humoral or cell-mediated vaccine response was 100% to measles and 94% to varicella in the CLD group post-vaccination, while it was 100% to both vaccines in controls. Our pilot study suggests that both live vaccines can be safely and effectively administered up to 14-days prior to transplantation in children with CLD. We anticipate this will improve vaccination rates and thus decrease rates of vaccine preventable infections in vulnerable children with CLD.

Immune Responses to Varicella-Zoster Virus Vaccines.

The live attenuated varicella vaccine is intended to mimic the tempo and nature of the humoral and cell-mediated immune responses to varicella infection. To date, two doses of varicella vaccine administered in childhood have been very effective in generating varicella-zoster virus (VZV) immune responses that prevent natural infection for at least several decades. After primary infection, the infecting VZV establishes latency in sensory and cranial nerve ganglia with the potential to reactivate and cause herpes zoster. Although, the immune responses developed during varicella are important for preventing herpes zoster they wane with increasing age (immune senescence) or with the advent of immune suppression. Protection can be restored by increasing cell-mediated immune responses with two doses of an adjuvanted recombinant VZV glycoprotein E vaccine that stimulates both VZV-and gE-specific immunity. This vaccine provides ~85-90% protection against herpes zoster for 7-8 years (to date).

Predictors of 5-Year Persistence of Antibody Responses to Zoster Vaccines.

BACKGROUND: Protection against herpes zoster is primarily conferred by cell-mediated immunity. However, anti-varicella-zoster virus (VZV) glycoprotein (anti-gp) antibody responses to zoster vaccine live (ZVL) are correlated with protection, suggesting a potential protective role for antibody. Detailed studies of antibody responses to the recombinant zoster vaccine (RZV) are provided. METHODS: We compared enzyme-linked immunosorbent assay-measured anti-VZV glycoproteins (anti-gp) and glycoprotein E (anti-gE) antibody levels and avidity in 159 participants randomized to RZV (n = 80) or ZVL (n = 79) recipients over 5 years after vaccination and identified predictors of antibody persistence. RESULTS: The comparison between vaccine groups showed higher anti-gE and anti-gp antibody levels after RZV than after ZVL over the 5-year study duration. RZV recipients also had higher anti-gE avidity for 5 years and higher anti-gp avidity in the first year after vaccination. Compared with prevaccination levels, RZV recipients maintained higher levels of anti-gE antibodies and avidity for 5 years, whereas ZVL recipients only maintained higher anti-gE avidity. Anti-gp antibody levels and avidity decreased to prevaccination levels or below beyond 1 year after vaccination in both groups. Independent predictors of persistence of antibody levels and avidity included vaccine type, prevaccination and peak antibody levels and avidity, prevaccination and peak cell-mediated immunity, and age. Sex or prior ZVL administration did not affect persistence. CONCLUSIONS: Antibody responses and avidity were higher and more persistent in RZV than in ZVL recipients. The effect of age on antibody persistence in RZV recipients is novel.

Breastfeeding Among People With Human Immunodeficiency Virus in North America: A Multisite Study.

BACKGROUND: In North American countries, national guidelines have strongly recommended formula over breastmilk for people with human immunodeficiency virus (HIV) because of concern for HIV transmission. However, data from resource-limited settings suggest the risk is <1% among virally suppressed people. Information regarding breastfeeding experience in high-resource settings is lacking. METHODS: A retrospective multisite study was performed for individuals with HIV who breastfed during 2014-2022 in the United States (8 sites) and Canada (3 sites). Descriptive statistics were used for data analysis. RESULTS: Among the 72 cases reported, most had been diagnosed with HIV and were on antiretroviral therapy prior to the index pregnancy and had undetectable viral loads at delivery. Most commonly reported reasons for choosing to breastfeed were health benefits, community expectations, and parent-child bonding. Median duration of breastfeeding was 24 weeks (range, 1 day to 72 weeks). Regimens for infant prophylaxis and protocols for testing of infants and birthing parents varied widely among institutions. No neonatal transmissions occurred among the 94% of infants for whom results were available ≥6 weeks after weaning. CONCLUSIONS: This study describes the largest cohort to date of people with HIV who breastfed in North America. Findings demonstrate high variability among institutions in policies, infant prophylaxis, and infant and parental testing practices. The study describes challenges in weighing the potential risks of transmission with personal and community factors. Finally, this study highlights the relatively small numbers of patients with HIV who chose to breastfeed at any 1 location, and the need for further multisite studies to identify best care practices.

Cytomegalovirus Immune reconstitution in cord blood transplant recipients on letermovir prophylaxis.

INTRODUCTION: Cytomegalovirus (CMV) can cause significant morbidity and mortality in cord blood transplant (CBT) recipients. Development of CMV-specific cell-mediated immunity (CMV-CMI) has been associated with protection against CMV clinically significant reactivation (CsCMV). In this study, we evaluated CMV-CMI reconstitution during letermovir prophylactic therapy, which prevents CsCMV without complete suppression of CMV reactivation. METHODS: We measured CMV-CMI in CMV-seropositive CBT recipients pre-transplant after Day+90 of letermovir prophylaxis and at Days +180, and +360- post-transplant using a dual color CMV-specific IFNγ/IL2 FLUOROSpot. CsCMV and nonCsCMV reactivations were abstracted from medical records. CsCMV was defined as CMV viral load ≥5,000 IU/ml using a whole blood assay. RESULTS: Among 70 CBT recipients, 31 developed CMV-CMI by Day+90 and an additional eight and five participants by Days +180 and +360, respectively. Thirty-eight participants developed CMV reactivation, including nine with CsCMV. Most reactivations (33 of 38) occurred before Day+180. Early CMV-CMI was present in six out of nine participants with CsCMV, indicating a lack of protection against CsCMV. Moreover, the magnitude of CMV-CMI at Day+90 did not differ between participants with CsCMV and nonCsCMV. CONCLUSION: Approximately 50% of CBT recipients reconstituted CMV-CMI during letermovir prophylactic therapy. However, CMV-CMI did not reach levels protective against CsCMV. Extension of CMV prophylaxis beyond Day+90 may be considered in CMV-seropositive CBT recipients.

Cell-Mediated Immune Responses After Administration of the Live or the Recombinant Zoster Vaccine: 5-Year Persistence.

We compared glycoprotein E (gE)- and varicella zoster virus (VZV)-specific Th1 immunity in 160 adults, aged 50-85 years, randomized to receive live or recombinant zoster vaccine (RZV). gE-specific responses measured by interferon-γ (IFN-γ) and interleukin 2 (IL-2) dual-color Fluorospot were significantly higher at all time points postimmunization in RZV recipients. VZV-specific IL-2+ memory, but not IFN-γ+ or IFN-γ+IL-2+ effector responses, were higher in RZV recipients at ≥3 months postimmunization. Only RZV recipients maintained higher postvaccination gE-specific IL-2+ and IFN-γ+ and VZV-specific IL-2+ responses for 5 years. The 5-year persistence of VZV-specific memory and gE-specific Th1 immunity may underlie superior RZV efficacy. Clinical Trials Registration NCT02114333.

Immunogenicity of Conjugated and Polysaccharide Pneumococcal Vaccines Administered During Pregnancy or Postpartum to Women With HIV.

BACKGROUND: Pneumococcal vaccination is recommended in people with HIV, prioritizing PCV. We compared the immunogenicity of PCV-10 and PPV-23 administered antepartum or postpartum. METHODS: This double-blind study randomized 346 pregnant women with HIV on antiretrovirals to PCV-10, PPV-23, or placebo at 14-34 weeks gestational age. Women who received placebo antepartum were randomized at 24 weeks postpartum to PCV-10 or PPV-23. Antibodies against 7 serotypes common to both vaccines and 1 serotype only in PPV-23 were measured by ELISA/chemiluminescence; B- and T-cell responses to serotype 1 by FLUOROSPOT; and plasma cytokines/chemokines by chemiluminescence. RESULTS: Antibody responses were higher after postpartum versus antepartum vaccination. PCV-10 generated lower antibody levels than PPV-23 against 4 and higher against 1 of 7 common serotypes. Additional factors associated with high postvaccination antibody concentrations were high prevaccination antibody concentrations and CD4+ cells; low CD8+ cells and plasma HIV RNA; and several plasma cytokines/chemokines. Serotype 1 B- and T-cell memory did not increase after vaccination. CONCLUSIONS: Antepartum immunization generated suboptimal antibody responses, suggesting that postpartum booster doses may be beneficial and warrant further studies. Considering that PCV-10 and PPV-23 had similar immunogenicity, but PPV-23 covered more serotypes, use of PPV-23 may be prioritized in women with HIV on antiretroviral therapy. CLINICAL TRAILS REGISTRATION: NCT02717494.

Effect of Maternal Immunization With 10-Valent Pneumococcus Conjugate Vaccine (PCV-10), 23-Valent Pneumococcus Polysaccharide Vaccine, or Placebo on the Immunogenicity of PCV-10 in Human Immunodeficiency Virus-Exposed Uninfected Infants: A Randomized Clinical Trial.

BACKGROUND: The effect of pneumococcal vaccination of mothers with human immunodeficiency virus (HIV) on infant responses to childhood vaccination has not been studied. We compared the immunogenicity of 10-valent pneumococcus conjugate vaccine (PCV-10) in HIV-exposed uninfected infants born to mothers who received PCV-10, 23-valent pneumococcus polysaccharide vaccine (PPV-23), or placebo during pregnancy. METHODS: Antibody levels against 7 serotypes were measured at birth, before the first and second doses of PCV-10m and after completion of the 2-dose regimen in 347 infants, including 112 born to mothers who received PPV-23, 112 who received PCV-10, and 119 who received placebo during pregnancy. Seroprotection was defined by antibody levels ≥0.35 µg/mL. RESULTS: At birth and at 8 weeks of life, antibody levels were similar in infants born to PCV-10 or PPV-23 recipients and higher than in those born to placebo recipient. After the last dose of PCV-10, infants in the maternal PCV-10 group had significantly lower antibody levels against 5 serotypes than those in the maternal PPV-23 group and against 3 serotypes than those in the maternal placebo group, and they did not have higher antibody levels against any serotype. The seroprotection rate against 7 serotypes was 50% in infants in the maternal PCV-10 group, compared with 71% in both of the maternal PPV-23 and placebo groups (P < .001). CONCLUSIONS: Administration of PCV-10 during pregnancy was associated with decreased antibody responses to PCV-10 and seroprotection rates in infants. Considering that PCV-10 and PPV-23 had similar immunogenicity in pregnant women with HIV and that administration of PPV-23 did not affect the immunogenicity of PCV-10 in infants, PPV-23 in pregnancy may be preferred over PCV-10.

Isoniazid Preventive Therapy in HIV-Infected Pregnant and Postpartum Women.

BACKGROUND: The safety, efficacy, and appropriate timing of isoniazid therapy to prevent tuberculosis in pregnant women with human immunodeficiency virus (HIV) infection who are receiving antiretroviral therapy are unknown. METHODS: In this multicenter, double-blind, placebo-controlled, noninferiority trial, we randomly assigned pregnant women with HIV infection to receive isoniazid preventive therapy for 28 weeks, initiated either during pregnancy (immediate group) or at week 12 after delivery (deferred group). Mothers and infants were followed through week 48 after delivery. The primary outcome was a composite of treatment-related maternal adverse events of grade 3 or higher or permanent discontinuation of the trial regimen because of toxic effects. The noninferiority margin was an upper boundary of the 95% confidence interval for the between-group difference in the rate of the primary outcome of less than 5 events per 100 person-years. RESULTS: A total of 956 women were enrolled. A primary outcome event occurred in 72 of 477 women (15.1%) in the immediate group and in 73 of 479 (15.2%) in the deferred group (incidence rate, 15.03 and 14.93 events per 100 person-years, respectively; rate difference, 0.10; 95% confidence interval [CI], -4.77 to 4.98, which met the criterion for noninferiority). Two women in the immediate group and 4 women in the deferred group died (incidence rate, 0.40 and 0.78 per 100 person-years, respectively; rate difference, -0.39; 95% CI, -1.33 to 0.56); all deaths occurred during the postpartum period, and 4 were from liver failure (2 of the women who died from liver failure had received isoniazid [1 in each group]). Tuberculosis developed in 6 women (3 in each group); the incidence rate was 0.60 per 100 person-years in the immediate group and 0.59 per 100 person-years in the deferred group (rate difference, 0.01; 95% CI, -0.94 to 0.96). There was a higher incidence in the immediate group than in the deferred group of an event included in the composite adverse pregnancy outcome (stillbirth or spontaneous abortion, low birth weight in an infant, preterm delivery, or congenital anomalies in an infant) (23.6% vs. 17.0%; difference, 6.7 percentage points; 95% CI, 0.8 to 11.9). CONCLUSIONS: The risks associated with initiation of isoniazid preventive therapy during pregnancy appeared to be greater than those associated with initiation of therapy during the postpartum period. (Funded by the National Institutes of Health; IMPAACT P1078 TB APPRISE ClinicalTrials.gov number, NCT01494038.).

Comparative Antibody Responses to the Live-Attenuated and Recombinant Herpes Zoster Vaccines.

Two herpes zoster (HZ) vaccines licensed in the United States are recommended by the Advisory Committee on Immunization Practices (ACIP): (i) live-attenuated vaccine (ZVL) using vOka strain varicella-zoster virus (VZV) and (ii) recombinant adjuvanted vaccine (RZV) containing recombinant varicella-zoster virus (VZV) glycoprotein E (gE). Two phase 3 clinical trials of RZV led the Advisory Committee on Immunization Practices (ACIP) to recommend it with preferred status. VZV T cell-mediated immunity (CMI), but not humoral immunity, is considered essential for protection against HZ. Published studies of humoral immunity focused on VZV-specific IgG concentration. To complement reports comparing the CMI responses to these vaccines, we compared humoral responses in ZVL and RZV recipients, emphasizing functional qualities (avidity and neutralization). Baseline avidities to a VZV glycoprotein mixture (gp) were near the upper limit of detection, but avidity to gE was much lower. Small increases in gp avidity were observed for both RZV and ZVL vaccination (19 and 12 avidity index units [AIU], respectively). RZV boosted both gE avidity and VZV neutralizing antibody significantly more than ZVL (mean gE avidity boost, 47 AIU versus 22 AIU; mean neutralizing antibody boost, 22-fold versus 8-fold). Increases in neutralizing antibodies strongly correlated with gE avidity increases (r = 0.5) and moderately with gp avidity increases (r = 0.23). After 1 year, 81% of RZV recipients and only 18% of ZVL recipients retained >50% of their peak avidity boosts. These results are consistent with the CMI responses to these vaccines: RZV responses are skewed to long-term memory, whereas ZVL preferentially induces transient effector responses.IMPORTANCE These observations further distinguish the immunogenicity and duration of the immune response of the two vaccines. In addition, measurements of functional humoral immunity (IgG avidity and neutralizing antibody) in response to zoster immunization, alone or combined with other immune markers, might contribute to practical in vitro correlates of protection. Combined with previous observations of the cell-mediated response to these vaccines, this study suggests that vaccine development will benefit from more expansive and granular assessments of acquired immunity during early phase 1 immunogenicity trials.

Humoral and cellular immune responses to recombinant herpes zoster vaccine in patients with chronic lymphocytic leukemia and monoclonal B cell lymphocytosis.

Monoclonal B-cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL) are clonal B-cell disorders associated with an increased risk of infections and impaired vaccination responses. We investigated the immunogenicity of recombinant zoster vaccine (RZV) in these patients. Individuals with MBL/untreated CLL and Bruton tyrosine kinase inhibitor (BTKi)-treated CLL patients were given two doses of RZV separated by 2 months. Responses assessed at 3 and 12 months from the first dose of RZV by an anti-glycoprotein E ELISA antibody assay and by dual-color Interferon-γ and Interleukin-2FLUOROSPOT assays were compared to historic controls matched by age and sex. About 62 patients (37 MBL/untreated CLL and 25 BTKi-treated CLL) were enrolled with a median age of 68 years at vaccination. An antibody response at 3 months was seen in 45% of participants, which was significantly lower compared to historic controls (63%, p = .03). The antibody response did not significantly differ between MBL/untreated CLL and BTKi-treated CLL (51% vs. 36%, respectively, p = .23). The CD4+ T-cell response to vaccination was significantly lower in study participants compared to controls (54% vs. 96%, p < .001), mainly due to lower responses among BTKi-treated patients compared to untreated MBL/CLL (32% vs. 73%, p = .008). Overall, only 29% of participants achieved combined antibody and cellular responses to RZV. Among participants with response assessment at 12 months (n = 47), 24% had antibody titers below the response threshold. Hypogammaglobulinemia and BTKi therapy were associated with reduced T-cell responses in a univariate analysis. Strategies to improve vaccine response to RZV among MBL/CLL patients are needed.

Immunologic and Virologic Factors Associated With Hospitalization in Human Immunodeficiency Virus-Exposed, Uninfected Infants in the United States.

BACKGROUND: Human immunodeficiency virus (HIV)-exposed, uninfected (HEU) infants experience higher rates of morbidity and mortality than HIV-unexposed, uninfected (HUU) infants. Few studies have examined whether particular infections and/or immune responses are associated with hospitalization among HEU infants born in the United States. METHODS: We evaluated a subset of HEU infants enrolled in the International Maternal Pediatric Adolescent AIDS Clinical Trials Group P1025 and/or Pediatric HIV/AIDS Cohort Study Surveillance Monitoring for ART Toxicities studies. We determined seroconversion to 6 respiratory viruses and measured antibody concentrations to 9 vaccine antigens using quantitative ELISA or electrochemiluminescence. Multivariable modified Poisson regression models were fit to evaluate associations of seroconversion to each respiratory virus/family and antibody concentrations to vaccine antigens with risk of hospitalization in the first year of life. Antibody concentrations to vaccine antigens were compared between HEU infants and HUU infants from a single site using multivariable linear regression models. RESULTS: Among 556 HEU infants, seroconversion to respiratory syncytial virus (RSV) and parainfluenza was associated with hospitalization (adjusted risk ratio, 1.95 [95% CI, 1.21-3.15] and 2.30 [1.42-3.73], respectively). Antibody concentrations to tetanus toxoid, pertussis, and pneumococcal vaccine antigens were higher among 525 HEU compared with 100 HUU infants. No associations were observed between antibody concentrations with any vaccine and hospitalization among HEU infants. CONCLUSIONS: RSV and parainfluenza contribute to hospitalization among HEU infants in the first year of life. HEU infants demonstrate robust antibody responses to vaccine antigens; therefore, humoral immune defects likely do not explain the increased susceptibility to infection observed in this population.

Using a Composite Maternal-Infant Outcome Measure in Tuberculosis-Prevention Studies Among Pregnant Women.

BACKGROUND: Tuberculosis (TB-)-preventive therapy (TPT) among pregnant women reduces risk of TB in mothers and infants, but timing of initiation should consider potential adverse effects. We propose an analytical approach to evaluate the risk-benefit of interventions. METHODS: A novel outcome measure that prioritizes maternal and infant events was developed with a 2-stage Delphi survey, where a panel of stakeholders assigned scores from 0 (best) to 100 (worst) based on perceived desirability. Using data from TB APPRISE, a trial among pregnant women living with human immunodeficiency virus (WLWH) that randomized the timing of initiation of isoniazid, antepartum versus postpartum, was evaluated. RESULTS: The composite outcome scoring/ranking system categorized mother-infant paired outcomes into 8 groups assigned identical median scores by stakeholders. Maternal/infant TB and nonsevere adverse pregnancy outcomes were assigned similar scores. Mean (SD) composite outcome scores were 43.7 (33.0) and 41.2 (33.7) in the antepartum and postpartum TPT initiation arms, respectively. However, a modifying effect of baseline antiretroviral regimen was detected (P = .049). When women received nevirapine, composite scores were higher (worse outcomes) in the antepartum versus postpartum arms (adjusted difference, 14.3; 95% confidence interval [CI], 2.4-26.2; P = .02), whereas when women received efavirenz there was no difference by timing of TPT (adjusted difference, .62; 95% CI, -3.2-6.2; P = .53). CONCLUSIONS: For TPT, when used by otherwise healthy persons, preventing adverse events is paramount from the perspective of stakeholders. Among pregnant WLWH in high-TB-burden regions, it is important to consider the antepartum antiretroviral regimen taken when deciding when to initiate TPT. Clinical Trials Registration. NCT01494038 (IMPAACT P1078).

Effects of Pregnancy and Isoniazid Preventive Therapy on Mycobacterium tuberculosis Interferon Gamma Response Assays in Women With HIV.

BACKGROUND: Pregnancy is accompanied by immune suppression. We hypothesized that Mycobacterium tuberculosis-specific inflammatory responses used to identify latent tuberculosis infection (LTBI) lose positivity during pregnancy. We also hypothesized that isoniazid preventive therapy (IPT) may revert LTBI diagnoses because of its sterilizing activity. METHODS: 944 women with human immunodeficiency virus infection (HIV) participating in a randomized, double-blind, placebo-controlled study comparing 28 weeks of IPT antepartum versus postpartum, were tested by QuantiFERON-gold-in-tube (QGIT) antepartum and by QGIT and tuberculin skin test (TST) at delivery and postpartum. Serial QGIT positivity was assessed by logistic regression using generalized estimating equations. RESULTS: From entry to delivery, 68 (24%) of 284 QGIT-positive women reverted to QGIT-negative or indeterminate. Of these, 42 (62%) recovered QGIT positivity postpartum. The loss of QGIT positivity during pregnancy was explained by decreased interferon gamma (IFNγ) production in response to TB antigen and/or mitogen. At delivery, LTBI was identified by QGIT in 205 women and by TST in 113 women. Corresponding numbers postpartum were 229 and 122 women. QGIT and TST kappa agreement coefficients were 0.4 and 0.5, respectively. Among QGIT-positive women antepartum or at delivery, 34 (12%) reverted to QGIT-negative after IPT. There were no differences between women who initiated IPT antepartum or postpartum. CONCLUSIONS: Decreased IFNγ responses in pregnancy reduced QGIT positivity, suggesting that this test cannot reliably rule out LTBI during pregnancy. TST was less affected by pregnancy, but had lower positivity compared to QGIT at all time points. IPT was associated with loss of QGIT positivity, the potential clinical consequences of which need to be investigated.

Individual and Composite Adverse Pregnancy Outcomes in a Randomized Trial on Isoniazid Preventative Therapy Among Women Living With Human Immunodeficiency Virus.

BACKGROUND: International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) P1078, a randomized noninferiority study designed to compare the safety of starting isoniazid preventive therapy (IPT) in women living with human immunodeficiency virus (HIV) either during pregnancy or after delivery, showed that IPT during pregnancy increased the risk of composite adverse pregnancy outcomes, but not individual outcomes. Many known factors are associated with adverse pregnancy outcomes: these factors' associations and effect modifications with IPT and pregnancy outcomes were examined. METHODS: Pregnant women living with HIV from 8 countries with tuberculosis incidences >60/100 000 were randomly assigned to initiate 28 weeks of IPT either during pregnancy or at 12 weeks after delivery. Using univariable and multivariable logistic regression and adjusting for factors associated with pregnancy outcomes, composite and individual adverse pregnancy outcome measures were analyzed. RESULTS: This secondary analysis included 925 mother-infant pairs. All mothers were receiving antiretrovirals. The adjusted odds of fetal demise, preterm delivery (PTD), low birth weight (LBW), or a congenital anomaly (composite outcome 1) were 1.63 times higher among women on immediate compared to deferred IPT (95% confidence interval [CI], 1.15-2.31). The odds of fetal demise, PTD, LBW, or neonatal death within 28 days (composite outcome 2) were 1.62 times higher among women on immediate IPT (95% CI, 1.14-2.30). The odds of early neonatal death within 7 days, fetal demise, PTD, or LBW (composite outcome 3) were 1.74 times higher among women on immediate IPT (95% CI, 1.22-2.49). CONCLUSIONS: We confirmed higher risks of adverse pregnancy outcomes associated with the initiation of IPT during pregnancy, after adjusting for known risk factors for adverse pregnancy outcomes.

Human Immunodeficiency Virus Exposure but Not Early Cytomegalovirus Infection Is Associated With Increased Hospitalization and Decreased Memory T-Cell Responses to Tetanus Vaccine.

BACKGROUND: Human immunodeficiency virus (HIV)-exposed, uninfected (HEU) infants experience high rates of infectious morbidity. We hypothesized that early cytomegalovirus (CMV) infection was associated with increased hospitalization rates and decreased vaccine responses in HEU compared with HIV-unexposed (HUU) infants. METHODS: Among infants enrolled in the Tshipidi study in Botswana, we determined CMV infection status by 6 months of age and compared hospitalization rates and responses to tetanus and Bacille Calmette-Guérin vaccines among HEU and HUU vaccinees. RESULTS: Fifteen of 226 (6.6%) HEU infants and 17 (19.3%) of 88 HUU infants were CMV-infected by 6 months. The HEU infants were approximately 3 times as likely to be hospitalized compared with HUU infants (P = .02). The HEU peripheral blood cells produced less interleukin (IL)-2 (P = .004), but similar amounts of interferon-γ, after stimulation with tetanus toxoid. Antitetanus immunoglobulin G titers were similar between groups. Cellular responses to purified protein derivative stimulation did not differ between groups. Maternal receipt of 3-drug antiretroviral therapy compared with zidovudine was associated with increased IL-2 expression after tetanus toxoid stimulation. The infants' CMV infection status was not associated with clinical or vaccine response outcomes. CONCLUSIONS: We observed that increased rates of hospitalization and decreased memory T-cell responses to tetanus vaccine were associated with HIV exposure and incomplete treatment of maternal HIV infection, but not early CMV infection.

Adjuvanted Recombinant Glycoprotein E Herpes Zoster Vaccine.

The adjuvanted recombinant glycoprotein E herpes zoster (HZ) vaccine is superior to the live attenuated HZ vaccine, with an efficacy >90% against HZ in healthy immunocompetent adults aged ≥50 years after vaccination. In pivotal studies, the efficacy of the new vaccine varied very little with the age of the vaccinee and decreased only by 5-10% in the 3.5 years after immunization. This nonlive vaccine was successfully administered to small cohorts of immunocompromised individuals; initial trials showed efficacy of >60-80% in several such settings. Potential drawbacks include the requirement for 2 vaccine doses separated by 2-6 months, local and systemic reactogenicity that is significantly greater than observed with commonly used vaccines, and the inclusion of a strong adjuvant that has been minimally studied in clinical settings where it might be problematic, such as in people with autoimmune diseases. Postmarketing studies are underway to address some of the drawbacks.

The Effect of Age on the Immunogenicity of the Live Attenuated Zoster Vaccine Is Predicted by Baseline Regulatory T Cells and Varicella-Zoster Virus-Specific T Cell Immunity.

Older age is associated with increased infectious morbidity and decreased immune responses to vaccines, but the mechanisms that mediate this effect are incompletely understood. The efficacy and immunogenicity of the live attenuated zoster vaccine (ZVL) have a very-well-described negative association with the age of the vaccinee. In a study of 600 ZVL recipients 50 to >80 years of age, we investigated immunological factors that might explain the effect of age on the immunogenicity of ZVL. Using FluoroSpot assays and flow cytometry, we determined that varicella-zoster virus (VZV)-specific peak T helper 1 (VZV-Th1) responses to ZVL were independently predicted by prevaccination VZV-Th1 responses, regulatory T cells (Treg), and PD1-expressing immune checkpoint T cells (Tcheck) but not by the age of the vaccinee. Persistence of VZV-Th1 1 year after vaccination was independently predicted by the factors mentioned above, by peak VZV-Th1 responses to ZVL, and by the age of the vaccinee. We further demonstrated by ex vivo blocking experiments the mechanistic role of PD1 and CTLA4 as modulators of decreased VZV-Th1 responses in the study participants. VZV-specific cytotoxic T cell (VZV-CTL) and T follicular helper responses to ZVL did not correlate with age, but similar to other Th1 responses, VZV-CTL peak and baseline responses were independently correlated. These data expand our understanding of the factors affecting the magnitude and kinetics of T cell responses to ZVL in older adults and show the importance of prevaccination Treg and Tcheck in modulating the immunogenicity of ZVL. This presents new potential interventions to increase vaccine responses in older adults.IMPORTANCE Vaccination is the most effective method to protect older adults against viral infections. However, the immunogenicity of viral vaccines in older adults is notoriously poor. The live attenuated zoster vaccine (ZVL) provides the best example of a gradual decrease of vaccine immunogenicity with every 10-year age increase above 50 years. Here we show that the abundance of regulatory T cells before vaccine administration to older adults has a significant inhibitory effect on immune responses to ZVL and, together with baseline immunity to varicella-zoster virus, explains the effect of age on the immunogenicity of ZVL. Moreover, in vitro blockade of regulatory T cell mechanisms of action with biologic modulators restores immune responses to varicella-zoster virus in vaccinees. Collectively, these observations suggest that immune modulators that block regulatory T cell activity may increase responses to viral attenuated vaccines in older adults.

Persistence of Varicella-Zoster Virus Cell-Mediated Immunity After the Administration of a Second Dose of Live Herpes Zoster Vaccine.

Protection against zoster conferred by zoster vaccine live (ZVL; Zostavax) wanes over time. We compared varicella-zoster virus cell-mediated immunity (VZV-CMI) of adults ≥70 years who received a second dose of ZVL ≥10 years after the initial dose with de novo-immunized age-matched controls. Before and during the first year after vaccination, VZV-CMI was significantly higher in reimmunized compared with de novo vaccinees. At 3 years, VZV-CMI differences between groups decreased and only memory responses remained marginally higher in reimmunized participants. In conclusion, the increase in VZV-CMI generated by reimmunization with ZVL is at least equally persistent compared with de novo immunization.