Defective T Memory Cell Differentiation after Varicella Zoster Vaccination in Older Individuals.

Vaccination with attenuated live varicella zoster virus (VZV) can prevent zoster reactivation, but protection is incomplete especially in an older population. To decipher the molecular mechanisms underlying variable vaccine responses, T- and B-cell responses to VZV vaccination were examined in individuals of different ages including identical twin pairs. Contrary to the induction of VZV-specific antibodies, antigen-specific T cell responses were significantly influenced by inherited factors. Diminished generation of long-lived memory T cells in older individuals was mainly caused by increased T cell loss after the peak response while the expansion of antigen-specific T cells was not affected by age. Gene expression in activated CD4 T cells at the time of the peak response identified gene modules related to cell cycle regulation and DNA repair that correlated with the contraction phase of the T cell response and consequently the generation of long-lived memory cells. These data identify cell cycle regulatory mechanisms as targets to reduce T cell attrition in a vaccine response and to improve the generation of antigen-specific T cell memory, in particular in an older population.

Enhanced natural killer-cell and T-cell responses to influenza A virus during pregnancy.

Pregnant women experience increased morbidity and mortality after influenza infection, for reasons that are not understood. Although some data suggest that natural killer (NK)- and T-cell responses are suppressed during pregnancy, influenza-specific responses have not been previously evaluated. Thus, we analyzed the responses of women that were pregnant (n = 21) versus those that were not (n = 29) immediately before inactivated influenza vaccination (IIV), 7 d after vaccination, and 6 wk postpartum. Expression of CD107a (a marker of cytolysis) and production of IFN-γ and macrophage inflammatory protein (MIP) 1ß were assessed by flow cytometry. Pregnant women had a significantly increased percentage of NK cells producing a MIP-1ß response to pH1N1 virus compared with nonpregnant women pre-IIV [median, 6.66 vs. 0.90% (P = 0.0149)] and 7 d post-IIV [median, 11.23 vs. 2.81% (P = 0.004)], indicating a heightened chemokine response in pregnant women that was further enhanced by the vaccination. Pregnant women also exhibited significantly increased T-cell production of MIP-1ß and polyfunctionality in NK and T cells to pH1N1 virus pre- and post-IIV. NK- and T-cell polyfunctionality was also enhanced in pregnant women in response to the H3N2 viral strain. In contrast, pregnant women had significantly reduced NK- and T-cell responses to phorbol 12-myristate 13-acetate and ionomycin. This type of stimulation led to the conclusion that NK- and T-cell responses during pregnancy are suppressed, but clearly this conclusion is not correct relative to the more biologically relevant assays described here. Robust cellular immune responses to influenza during pregnancy could drive pulmonary inflammation, explaining increased morbidity and mortality.

Pregnancy Does Not Attenuate the Antibody or Plasmablast Response to Inactivated Influenza Vaccine.

BACKGROUND: Inactivated influenza vaccine (IIV) is recommended during pregnancy to prevent influenza infection and its complications in pregnant women and their infants. However, the extent to which pregnancy modifies the antibody response to vaccination remains unclear, and prior studies have focused primarily on hemagglutinin inhibition (HI) titers. A more comprehensive understanding of how pregnancy modifies the humoral immune response to influenza vaccination will aid in maximizing vaccine efficacy. METHODS: Healthy pregnant women and control women were studied prior to, 7 days after, and 28 days after vaccination with IIV. HI titers, microneutralization (MN) titers, and the frequency of circulating plasmablasts were evaluated in pregnant versus control women. RESULTS: Pregnant women and control women mount similarly robust serologic immune responses to IIV, with no significant differences for any influenza strain in postvaccination geometric mean HI or MN titers. HI and MN titers correlate, though MN titers demonstrate more robust changes pre- versus postvaccination. The induction of circulating plasmablasts is increased in pregnant women versus controls (median fold-change 2.60 vs 1.49 [interquartile range, 0.94-7.53 vs 0.63-2.67]; P = .03). CONCLUSIONS: Pregnant women do not have impaired humoral immune responses to IIV and may have increased circulating plasmablast production compared to control women.

Engagement With Remote Delivery Channels in a Physical Activity Intervention for Senior Women in the US.

PURPOSE: Identify the effects of engagement with different intervention delivery channels on physical activity (PA), and the participant subgroups engaging with the different channels, among Women's Health Initiative Strong and Healthy (WHISH) PA trial participants. DESIGN: Secondary analysis of data from WHISH, a pragmatic trial that used passive randomized consent. SETTING: United States (remote intervention in all 50 states). SAMPLE: 18,080 U.S. women, aged 68-99 years, assigned to the WHISH PA intervention arm. MEASURES: 6 dichotomous variables operationalized engagement: Engagement with Targeted Inserts, Email (opened), Email (clicked links), Website (logging in), Website (tracking), Interactive Voice Response (IVR). PA was measured using the CHAMPS PA questionnaire. ANALYSIS: Linear regressions evaluated effects of engagement on PA. Conditional Inference Trees identified subgroups of participants engaging with different channels based on demographic and psychosocial variables. RESULTS: Engagement with each channel, except IVR, was associated with significantly more hours/week of PA (square root coefficients .29 - .13, P values <.001). Consistently across channels, features that identified subgroups of participants with higher engagement included younger age, and higher levels of PA and physical function. Subgroups with the highest engagement differed from those with the lowest in most participant characteristics. CONCLUSIONS: For equitable population-level impact via large-scale remotely-delivered PA programs, it may be necessary to identify strategies to engage and target harder to reach subgroups more precisely. CLINICAL TRIAL REGISTRATION: The WHISH trial is registered at ClinicalTrials.gov (No. NCT02425345).

What moves you? Physical activity strategies in older women.

Physical activity improves quality of life and extends independence in older adults. Yet, how to motivate older adults to engage in physical activity is unclear. In the present study, 4108 older women, aged 70-99, reported how they motivated themselves to move when they did not feel like it, and their hours of physical activity and walking each week. Findings indicated that participants who endorsed more strategies had more hours of physical activity and walking. Strategic categories that correlated with more physical activity include focusing on the benefits and utilizing the surrounding environment to help motivate movement.

Physical activity, well-being, and priorities of older women during the COVID-19 pandemic: a survey of Women's Health Initiative Strong and Healthy (WHISH) intervention participants.

Sheltering-in-place, social distancing, and other strategies to minimize COVID-19 transmission may impact physical activity (PA) and well-being in older adults. To assess self-reported PA changes, well-being, and priorities of older women across the USA early in the COVID-19 pandemic. In May 2020, a 10-question survey was emailed to 5,822 women, aged over 70 years, who had been assigned to the Women's Health Initiative (WHI) Strong and Healthy (WHISH) trial PA intervention and had provided email addresses. The survey assessed general and physical well-being, current priorities, and PA levels before and during the COVID-19 pandemic. Demographic and physical function data were collected previously. Descriptive analyses characterized participants' priorities and PA changes from before the pandemic to the time of data collection during the pandemic. Differences in PA change by age, physical function, and geographic region were assessed by Kruskal-Wallis and post hoc Dunn tests. Among 2,876 survey respondents, 89% perceived their general well-being as good, very good, or excellent, despite 90% reporting at least moderate (to extreme) concern about the pandemic, with 18.2% reporting increased PA levels, 27.1% reporting no changes, and 54.7% reporting decreased PA levels. Top priorities "in the midst of the COVID-19 outbreak" were staying in touch with family/friends (21%) and taking care of one's body (20%). Among priorities related to physical well-being, staying active was selected most frequently (33%). Support for maintaining PA in older populations should be a priority during a pandemic and similarly disruptive events.

Women's Health Initiative Strong and Healthy Pragmatic Physical Activity Intervention Trial for Cardiovascular Disease Prevention: Design and Baseline Characteristics.

BACKGROUND: National guidelines promote physical activity to prevent cardiovascular disease (CVD), yet no randomized controlled trial has tested whether physical activity reduces CVD. METHODS: The Women's Health Initiative (WHI) Strong and Healthy (WHISH) pragmatic trial used a randomized consent design to assign women for whom cardiovascular outcomes were available through WHI data collection (N = 18 985) or linkage to the Centers for Medicare and Medicaid Services (N30 346), to a physical activity intervention or "usual activity" comparison, stratified by ages 68-99 years (in tertiles), U.S. geographic region, and outcomes data source. Women assigned to the intervention could "opt out" after receiving initial physical activity materials. Intervention materials applied evidence-based behavioral science principles to promote current national recommendations for older Americans. The intervention was adapted to participant input regarding preferences, resources, barriers, and motivational drivers and was targeted for 3 categories of women at lower, middle, or higher levels of self-reported physical functioning and physical activity. Physical activity was assessed in both arms through annual questionnaires. The primary outcome is major cardiovascular events, specifically myocardial infarction, stroke, or CVD death; primary safety outcomes are hip fracture and non-CVD death. The trial is monitored annually by an independent Data Safety and Monitoring Board. Final analyses will be based on intention to treat in all randomized participants, regardless of intervention engagement. RESULTS: The 49 331 randomized participants had a mean baseline age of 79.7 years; 84.3% were White, 9.2% Black, 3.3% Hispanic, 1.9% Asian/Pacific Islander, 0.3% Native American, and 1% were of unknown race/ethnicity. The mean baseline RAND-36 physical function score was 71.6 (± 25.2 SD). There were no differences between Intervention (N = 24 657) and Control (N = 24 674) at baseline for age, race/ethnicity, current smoking (2.5%), use of blood pressure or lipid-lowering medications, body mass index, physical function, physical activity, or prior CVD (10.1%). CONCLUSION: The WHISH trial is rigorously testing whether a physical activity intervention reduces major CV events in a large, diverse cohort of older women. Clinical Trials Registration Number: NCT02425345.

Longitudinal Kinetics of Cytomegalovirus-Specific T-Cell Immunity and Viral Replication in Infants With Congenital Cytomegalovirus Infection.

BACKGROUND: Congenital cytomegalovirus (CMV) is reported to affect up to 1% of all live births in the United States. T-cell immunity may be important for controlling CMV replication in congenital CMV-infected infants. We describe the natural history of CMV-specific T-cell evolution and CMV replication in infants with congenital CMV infection. METHODS: Cytomegalovirus viral load, CMV urine culture, and CMV-specific CD4 and CD8 T-cell responses were assessed in a prospective longitudinal cohort of 51 infants with congenital CMV infection who were observed from birth to 3 years of age. RESULTS: We found a kinetic pattern of decreasing urinary CMV replication and increasing CMV-specific CD4 and CD8 T-cell responses during the first 3 years of life. We also found higher CMV-specific CD8 T-cell responses were associated with subsequent reduction of urine CMV viral load. CONCLUSION: For infants with congenital CMV infection, our data suggest an age-related maturation of both CMV-specific CD4 and CD8 T-cell immunity that is associated with an age-related decline in urinary CMV replication.

Lineage tracing of human B cells reveals the in vivo landscape of human antibody class switching.

Antibody class switching is a feature of the adaptive immune system which enables diversification of the effector properties of antibodies. Even though class switching is essential for mounting a protective response to pathogens, the in vivo patterns and lineage characteristics of antibody class switching have remained uncharacterized in living humans. Here we comprehensively measured the landscape of antibody class switching in human adult twins using antibody repertoire sequencing. The map identifies how antibodies of every class are created and delineates a two-tiered hierarchy of class switch pathways. Using somatic hypermutations as a molecular clock, we discovered that closely related B cells often switch to the same class, but lose coherence as somatic mutations accumulate. Such correlations between closely related cells exist when purified B cells class switch in vitro, suggesting that class switch recombination is directed toward specific isotypes by a cell-autonomous imprinted state.

Defective Signaling in the JAK-STAT Pathway Tracks with Chronic Inflammation and Cardiovascular Risk in Aging Humans.

Chronic inflammation, a decline in immune responsiveness, and reduced cardiovascular function are all associated with aging, but the relationships among these phenomena remain unclear. Here, we longitudinally profiled a total of 84 signaling conditions in 91 young and older adults and observed an age-related reduction in cytokine responsiveness within four immune cell lineages, most prominently T cells. The phenotype can be partially explained by elevated baseline levels of phosphorylated STAT (pSTAT) proteins and a different response capacity of naive versus memory T cell subsets to interleukin 6 (IL-6), interferon α (IFN-α), and, to a lesser extent, IL-21 and IFN-γ. Baseline pSTAT levels tracked with circulating levels of C-reactive protein (CRP), and we derived a cytokine response score that negatively correlates with measures of cardiovascular disease, specifically diastolic dysfunction and atherosclerotic burden, outperforming CRP. Thus, we identified an immunological link between inflammation, decreased cell responsiveness in the JAK-STAT pathway, and cardiovascular aging. Targeting chronic inflammation may ameliorate this deficiency in cellular responsiveness and improve cardiovascular function.

Diversification of the antigen-specific T cell receptor repertoire after varicella zoster vaccination.

Diversity and size of the antigen-specific T cell receptor (TCR) repertoire are two critical determinants for successful control of chronic infection. Varicella zoster virus (VZV) that establishes latency during childhood can escape control mechanisms, in particular with increasing age. We examined the TCR diversity of VZV-reactive CD4 T cells in individuals older than 50 years by studying three identical twin pairs and three unrelated individuals before and after vaccination with live attenuated VZV. Although all individuals had a small number of dominant T cell clones, the breadth of the VZV-specific repertoire differed markedly. A genetic influence was seen for the sharing of individual TCR sequences from antigen-reactive cells but not for repertoire richness or the selection of dominant clones. VZV vaccination favored the expansion of infrequent VZV antigen-reactive TCRs, including those from naïve T cells with lesser boosting of dominant T cell clones. Thus, vaccination does not reinforce the in vivo selection that occurred during chronic infection but leads to a diversification of the VZV-reactive T cell repertoire. However, a single-booster immunization seems insufficient to establish new clonal dominance. Our results suggest that repertoire analysis of antigen-specific TCRs can be an important readout to assess whether a vaccination was able to generate memory cells in clonal sizes that are necessary for immune protection.

Mapping epitopes of U1-70K autoantibodies at single-amino acid resolution.

The mechanisms underlying development of ribonucleoprotein (RNP) autoantibodies are unclear. The U1-70K protein is the predominant target of RNP autoantibodies, and the RNA binding domain has been shown to be the immunodominant autoantigenic region of U1-70K, although the specific epitopes are not known. To precisely map U1-70K epitopes, we developed silicon-based peptide microarrays with >5700 features, corresponding to 843 unique peptides derived from the U1-70K protein. The microarrays feature overlapping peptides, with single-amino acid resolution in length and location, spanning amino acids 110-170 within the U1-70K RNA binding domain. We evaluated the serum IgG of a cohort of patients with systemic lupus erythematosus (SLE; n = 26) using the microarrays, and identified multiple reactive epitopes, including peptides 116-121 and 143-148. Indirect peptide ELISA analysis of the sera of patients with SLE (n = 88) revealed that ∼14% of patients had serum IgG reactivity to 116-121, while reactivity to 143-148 appeared to be limited to a single patient. SLE patients with serum reactivity to 116-121 had significantly lower SLE Disease Activity Index (SLEDAI) scores at the time of sampling, compared to non-reactive patients. Minimal reactivity to the peptides was observed in the sera of healthy controls (n = 92). Competitive ELISA showed antibodies to 116-121 bind a common epitope in U1-70K (68-72) and the matrix protein M1 of human influenza B viruses. Institutional Review Boards approved this study. Knowledge of the precise epitopes of U1-70K autoantibodies may provide insight into the mechanisms of development of anti-RNP, identify potential clinical biomarkers and inform ongoing clinical trails of peptide-based therapeutics.

Randomized, placebo-controlled trial to assess the safety and immunogenicity of an adenovirus type 35-based circumsporozoite malaria vaccine in healthy adults.

Malaria results in over 650,000 deaths each year; thus, there is an urgent need for an effective vaccine. Pre-clinical studies and recently reported human trials suggest that pre-erythrocytic stage vaccines can provide protection against infection. A Phase 1, randomized, placebo-controlled, dose-escalation study was conducted with a vaccine composed of a replication-deficient adenovirus-35 backbone with P. falciparum circumsporozoite (CS) surface antigen (Ad35.CS.01). Healthy adult subjects received three doses of 10 (8), 10 (9), 10 (10), or 10 (11) vp/mL Ad35.CS.01 vaccine or saline placebo intramuscularly at 0, 1, and 6-mo intervals. Adverse events were assessed and anti-CS antibody responses were determined by ELISA. Seventy-two individuals were enrolled, with age, gender, and ethnicity similar across each study arm. While the vaccine was generally well tolerated, adverse events were more frequent in the highest dose groups (10 (10) and 10 (11) vp/mL). More robust humoral responses were also noted at the highest doses, with 73% developing a positive ELISA response after the three dose series of 10 (11) vp/mL. The Ad35.CS.01 vaccine was most immunogenic at the highest dosages (10 (10) and 10 (11) vp/mL). Reactogenicity findings were more common after the 10 (11) vp/mL dose, although most were mild or moderate in nature and resolved without therapy.

Genetic and environmental determinants of human NK cell diversity revealed by mass cytometry.

Natural killer (NK) cells play critical roles in immune defense and reproduction, yet remain the most poorly understood major lymphocyte population. Because their activation is controlled by a variety of combinatorially expressed activating and inhibitory receptors, NK cell diversity and function are closely linked. To provide an unprecedented understanding of NK cell repertoire diversity, we used mass cytometry to simultaneously analyze 37 parameters, including 28 NK cell receptors, on peripheral blood NK cells from 5 sets of monozygotic twins and 12 unrelated donors of defined human leukocyte antigen (HLA) and killer cell immunoglobulin-like receptor (KIR) genotype. This analysis revealed a remarkable degree of NK cell diversity, with an estimated 6000 to 30,000 phenotypic populations within an individual and >100,000 phenotypes in the donor panel. Genetics largely determined inhibitory receptor expression, whereas activation receptor expression was heavily environmentally influenced. Therefore, NK cells may maintain self-tolerance through strictly regulated expression of inhibitory receptors while using adaptable expression patterns of activating and costimulatory receptors to respond to pathogens and tumors. These findings further suggest the possibility that discrete NK cell subpopulations could be harnessed for immunotherapeutic strategies in the settings of infection, reproduction, and transplantation.