Impact of aging and HIV infection on serologic response to seasonal influenza vaccination

Soluble Plasma Proteins of Tumor Necrosis Factor and Immunoglobulin Superfamilies Reveal New Insights into Immune Regulation in People with HIV and Opioid Use Disorder

People with HIV (PWH) frequently suffer from Opioid (OP) Use Disorder (OUD). In an investigation of the impact of OUD on underlying immune dysfunction in PWH, we previously reported that OP use exacerbates inflammation in virally controlled PWH followed in the Infectious Diseases Elimination Act (IDEA) Syringe Services Program (SSP). Unexpectedly, Flu vaccination-induced antibody responses in groups with OUD were superior to PWH without OUD. Here, we investigated the profile of 48 plasma biomarkers comprised of TNF and Ig superfamily (SF) molecules known to impact interactions between T and B cells in 209 participants divided into four groups: (1) HIV+OP+, (2) HIV-OP+, (3) HIV+OP-, and (4) HIV-OP-. The differential expression of the top eight molecules ranked by median values in individual Groups 1-3 in comparison to Group 4 was highly significant. Both OP+ groups 1 and 2 had higher co-stimulatory TNF SF molecules, including 4-1BB, OX-40, CD40, CD30, and 4-1BBL, which were found to positively correlate with Flu Ab titers. In contrast, HIV+OP- exhibited a profile dominant in Ig SF molecules, including PDL-2, CTLA-4, and Perforin, with PDL-2 showing a negative correlation with Flu vaccine titers. These findings are relevant to vaccine development in the fields of HIV and OUD.

Immunological and Clinical Responses to Vaccinations among Adults Living with HIV

People living with human immunodeficiency virus (HIV) are at higher risk of morbidity and mortality due to vaccine-preventable diseases. At the same time, they are less likely to respond to vaccinations, and might have a higher rate of vaccine adverse event and faster waning of protective effect. International and national guidelines emphasize the importance of vaccinating people living with HIV against respiratory system disease pathogens including seasonal influenza, Streptococcus pneumoniae, and COVID-19, as well as against sexually transmitted infections, i.e., Hepatitis A and B (HAV, HBV) and human papillomavirus (HPV). This narrative review aims to provide a comprehensive examination of the current knowledge regarding the immune and clinical responses elicited by vaccinations in the older adult population living with HIV.

Factors Associated with Neutralizing Antibody Responses following 2-Dose and 3rd Booster Monovalent COVID-19 Vaccination in Japanese People Living with HIV

People living with HIV (PLWH) could be at risk of blunted immune responses to COVID-19 vaccination. We investigated factors associated with neutralizing antibody (NAb) responses against SARS-CoV-2 and variants of concern (VOCs), following two-dose and third booster monovalent COVID-19 mRNA vaccination in Japanese PLWH. NAb titers were assessed in polyclonal IgG fractions by lentiviral-based pseudovirus assays. Overall, NAb titers against Wuhan, following two-dose vaccination, were assessed in 82 PLWH on treatment, whereby 17/82 (20.73%) were classified as low-NAb participants. Within the low-NAb participants, the third booster vaccination enhanced NAb titers against Wuhan and VOCs, albeit to a significantly lower magnitude than the rest. In the multivariate analysis, NAb titers against Wuhan after two-dose vaccination correlated with age and days since vaccination, but not with CD4+ count, CD4+/CD8+ ratio, and plasma high-sensitivity C-Reactive protein (hsCRP). Interestingly, an extended analysis within age subgroups revealed NAb titers to correlate positively with the CD4+ count and negatively with plasma hsCRP in younger, but not older, participants. In conclusion, a third booster vaccination substantially enhances NAb titers, but the benefit may be suboptimal in subpopulations of PLWH exhibiting low titers at baseline. Considering clinical and immune parameters could provide a nuanced understanding of factors associated with vaccine responses in PLWH.

A meta-analysis of immunogenicity and safety of two versus single-doses of influenza A (H1N1) vaccine in person living with HIV

Purpose: Influenza vaccination of person living with HIV (PLWH) is a powerful means to tackle severe clinical outcomes. Few data on two doses of influenza vaccine in PLWH are available.Research Design: To evaluate the immunogenicity and safety of two doses of vaccine as compared with single dose in PLWH, we searched Pubmed, Embase, and web of science databases for relevant articles (January 2009 to April 2023). Pooled SMD or RR and 95% CI were calculated.Results: A total of 2436 participants from 14 studies were included. Compared to single dose influenza vaccine regimen, the pooled RR of seroprotection and seroconversion for two doses of vaccines was 1.14 (95%CI: 1.08-1.21) and 1.25 (95%CI: 1.16-1.34), respectively; the SMD of GMT was 0.42 (95%CI: 0.35, 0.49). Regarding safety, the fever risk in PLWH receiving two doses of vaccine was 3.42 fold higher than that of single dose vaccine, and the risk of myalgia had a quarter reduction. No serious vaccine-related adverse events were reported.Conclusions: Collectively, two doses of the vaccine are associated with a better immunogenicity and an acceptable safety in PLWH. Two doses of the adjuvant vaccination might be a superior vaccination regimen.nation regimen.

Preservation of memory B cell homeostasis in an individual producing broadly neutralising antibodies against HIV-1

Immunological determinants favouring emergence of broadly neutralising antibodies are crucial to the development of HIV-1 vaccination strategies. Here, we combined RNAseq and B cell cloning approaches to isolate a broadly neutralising antibody (bnAb) ELC07 from an individual living with untreated HIV-1. Using single particle cryogenic electron microscopy (cryo-EM), we show that the antibody recognises a conformational epitope at the gp120-gp41 interface. ELC07 binds the closed state of the viral glycoprotein causing considerable perturbations to the gp41 trimer core structure. Phenotypic analysis of memory B cell subsets from the ELC07 bnAb donor revealed a lack of expected HIV-1-associated dysfunction, specifically no increase in CD21-/CD27- cells was observed whilst the resting memory (CD21+/CD27+) population appeared preserved despite uncontrolled HIV-1 viraemia. Moreover, single cell transcriptomes of memory B cells from this bnAb donor showed a resting memory phenotype irrespective of the epitope they targeted or their ability to neutralise diverse strains of HIV-1. Strikingly, single memory B cells from the ELC07 bnAb donor were transcriptionally similar to memory B cells from HIV-negative individuals. Our results demonstrate that potent bnAbs can arise without the HIV-1-induced dysregulation of the memory B cell compartment and suggest that sufficient levels of antigenic stimulation with a strategically designed immunogen could be effective in HIV-negative vaccine recipients.

Trends in COVID-19 admissions and deaths among people living with HIV in South Africa: analysis of national surveillance data

BACKGROUND

In 2021, the HIV prevalence among South African adults was 18% and more than 2 million people had uncontrolled HIV and, therefore, had increased risk of poor outcomes with SARS-CoV-2 infection. We investigated trends in COVID-19 admissions and factors associated with in-hospital COVID-19 mortality among people living with HIV and people without HIV.

METHODS

In this analysis of national surveillance data, we linked and analysed data collected between March 5, 2020, and May 28, 2022, from the DATCOV South African national COVID-19 hospital surveillance system, the SARS-CoV-2 case line list, and the Electronic Vaccination Data System. All analyses included patients hospitalised with SARS-CoV-2 with known in-hospital outcomes (ie, who were discharged alive or had died) at the time of data extraction. We used descriptive statistics for admissions and mortality trends. Using post-imputation random-effect multivariable logistic regression models, we compared characteristics and the case fatality ratio of people with HIV and people without HIV. Using modified Poisson regression models, we compared factors associated with mortality among all people with COVID-19 admitted to hospital and factors associated with mortality among people with HIV.

FINDINGS

Among 397 082 people with COVID-19 admitted to hospital, 301 407 (75·9%) were discharged alive, 89 565 (22·6%) died, and 6110 (1·5%) had no recorded outcome. 270 737 (68·2%) people with COVID-19 had documented HIV status (22 858 with HIV and 247 879 without). Comparing characteristics of people without HIV and people with HIV in each COVID-19 wave, people with HIV had increased odds of mortality in the D614G (adjusted odds ratio 1·19, 95% CI 1·09-1·29), beta (1·08, 1·01-1·16), delta (1·10, 1·03-1·18), omicron BA.1 and BA.2 (1·71, 1·54-1·90), and omicron BA.4 and BA.5 (1·81, 1·41-2·33) waves. Among all COVID-19 admissions, mortality was lower among people with previous SARS-CoV-2 infection (adjusted incident rate ratio 0·32, 95% CI 0·29-0·34) and with partial (0·93, 0·90-0·96), full (0·70, 0·67-0·73), or boosted (0·50, 0·41-0·62) COVID-19 vaccination. Compared with people without HIV who were unvaccinated, people without HIV who were vaccinated had lower risk of mortality (0·68, 0·65-0·71) but people with HIV who were vaccinated did not have any difference in mortality risk (1·08, 0·96-1·23). In-hospital mortality was higher for people with HIV with CD4 counts less than 200 cells per μL, irrespective of viral load and vaccination status.

INTERPRETATION

HIV and immunosuppression might be important risk factors for mortality as COVID-19 becomes endemic.

FUNDING

South African National Institute for Communicable Diseases, the South African National Government, and the United States Agency for International Development.

IL-21-IgFc immunotherapy alters transcriptional landscape of lymph node cells leading to enhanced flu vaccine response in aging and SIV infection

Aging people living with HIV (PWH) frequently manifest impaired antibody (Ab) responses to seasonal flu vaccination which has been attributed to ongoing inflammation and immune activation. We have recently reported a similar scenario in old simian immunodeficiency virus (SIV) infected rhesus macaques (RM) with controlled viremia and have been able to compensate for this deficiency by immunotherapy with interleukin (IL)-21-IgFc. To understand the underlying mechanisms of IL-21-induced immunomodulation leading to enhanced flu vaccine response in aging and SIV, we have investigated draining lymph node (LN) cells of IL-21-treated and -untreated animals at postvaccination. We observed IL-21-induced proliferation of flu-specific LN memory CD4 T cells, expansion of B cells expressing IL-21 receptor (IL-21R), and modest expansion of T follicular helper cells (Tfh) co-expressing T-cell immunoreceptor with Ig and ITIM domains (TIGIT) and DNAX accessory molecule (DNAM-1). Transcriptional analysis of LN cells of IL-21-treated animals revealed significant inhibition of germinal center (GC) Tfh and B-cell interferon signaling pathways along with enhanced B-cell development and antigen presentation pathways. We conclude that IL-21 treatment at the time of flu vaccination in aging SIV-infected animals modulates the inductive LN GC activity, to reverse SIV-associated LN Tfh and B-cell dysfunction. IL-21 is a potential candidate molecule for immunotherapy to enhance flu vaccine responses in aging PWH who have deficient antibody responses.

Antibody neutralization capacity after coronavirus disease 2019 vaccination in people with HIV in Canada

OBJECTIVES

Many vaccines require higher/additional doses or adjuvants to provide adequate protection for people with HIV (PWH). Here, we compare coronavirus disease 2019 (COVID-19) vaccine-induced antibody neutralization capacity in PWH vs. HIV-negative individuals following two vaccine doses.

DESIGN

In Canadian prospective observational cohorts, including a multicentre study of PWH receiving at least two COVID-19 vaccinations (mRNA or ChAdOx1-S), and a parallel study of HIV-negative controls (Stop the Spread Ottawa Cohort), we measured vaccine-induced neutralization capacity 3 months post dose 2 (±1 month).

METHODS

COVID-19 neutralization efficiency was measured by calculating the half maximal inhibitory dilution (ID50) using a high-throughput protein-based neutralization assay for Ancestral (Wuhan), Delta and Omicron (BA.1) spike variants. Univariable and multivariable quantile regression were used to compare COVID-19-specific antibody neutralization capacity by HIV status.

RESULTS

Neutralization assays were performed on 256 PWH and 256 controls based on specimen availability at the timepoint of interest, having received two vaccines and known date of vaccination. There was a significant interaction between HIV status and previous COVID-19 infection status in median ID50. There were no differences in median ID50 for HIV+ vs. HIV-negative persons without past COVID-19 infection. For participants with past COVID-19 infection, median ICD50 was significantly higher in controls than in PWH for ancestral SARS-CoV-2 and Omicron variants, with a trend for the Delta variant in the same direction.

CONCLUSION

Vaccine-induced SARS-CoV-2 neutralization capacity was similar between PWH vs. HIV-negative persons without past COVID-19 infection, demonstrating favourable humoral-mediated immunogenicity. Both HIV+ and HIV-negative persons demonstrated hybrid immunity.

TRIAL REGISTRATION

clinicaltrials.gov NCT04894448.

Immunogenicity and Efficacy of Vaccination in People Living with Human Immunodeficiency Virus

People living with HIV (PLWH) remain at high risk of mortality and morbidity from vaccine-preventable diseases, even though antiretroviral therapy (ART) has restored life expectancy and general well-being. When, which, and how many doses of vaccine should be administered over the lifetime of PLWH are questions that have become clinically relevant. Immune responses to most vaccines are known to be impaired in PLWH. Effective control of viremia with ART and restored CD4+ T-cell count are correlated with an improvement in responsiveness to routine vaccines. However, the presence of immune alterations, comorbidities and co-infections may alter it. In this article, we provide a comprehensive review of the literature on immune responses to different vaccines in the setting of HIV infection, emphasizing the potential effect of HIV-related factors and presence of comorbidities in modulating such responses. A better understanding of these issues will help guide vaccination and prevention strategies for PLWH.

Serological response following COVID-19 vaccines in patients living with HIV: a dose-response meta-analysis

To quantify the pooled rate and risk ratio of seroconversion following the uncomplete, complete, or booster dose of COVID-19 vaccines in patients living with HIV. PubMed, Embase and Cochrane library were searched for eligible studies to perform a systematic review and meta-analysis based on PRIMSA guidelines. The pooled rate and risk ratio of seroconversion were assessed using the Freeman-Tukey double arcsine method and Mantel-Haenszel approach, respectively. Random-effects model was preferentially used as the primary approach to pool results across studies. A total of 50 studies involving 7160 patients living with HIV were analyzed. We demonstrated that only 75.0% (56.4% to 89.9%) patients living with HIV achieved a seroconversion after uncomplete vaccination, which improved to 89.3% (84.2% to 93.5%) after complete vaccination, and 98.4% (94.8% to 100%) after booster vaccination. The seroconversion rates were significantly lower compared to controls at all the stages, while the risk ratios for uncomplete, complete, and booster vaccination were 0.87 (0.77 to 0.99), 0.95 (0.92 to 0.98), and 0.97 (0.94 to 0.99), respectively. We concluded that vaccine doses were associated with consistently improved rates and risk ratios of seroconversion in patients living with HIV, highlighting the significance of booster vaccination for patients living with HIV.

Adverse events and SARS-CoV-2 antibody responses after immunization with Sputnik V, ChAdOx1-S, and BBIBP-CorV vaccines in people with HIV

OBJECTIVE

This study describes adverse events following immunization (AEFIs) and the development of SARS-COV-2 antibodies after Sputnik V, AstraZeneca, and Sinopharm COVID-19 vaccination in people with HIV (PWH).

METHODS

In total, 595 adult PWH at an HIV center in Argentina from March to December 2021 were enrolled. Analysis included participants who received COVID-19 vaccination with Sputnik V, AstraZeneca, and Sinopharm, and did not receive mRNA COVID-19 vaccines. Clinical data, and local or systemic AEFI variables were collected using an online questionnaire after the first dose. Detection of S1-RBD IgG antibodies was performed between days 28 and 60 after the second dose in a subsample (SARS-CoV-2 IgG chemiluminescent immunoassay; Siemens). A multivariable logistic regression and spearman test were used for analyses.

RESULTS

Mean age was 46.1 years (SD = 11.8); 70.4% were men; and median CD4 + T cells count was 659 (500-852) cells/μl. AEFIs were reported in 214 (36.0%) participants. More participants reported AEFIs after Sputnik V (29.4%) and AstraZeneca (47.5%) than Sinopharm (13.9%) (χ 2  = 35.85, P  < 0.001). Higher odds of reporting an AEFIs were associated with receiving Sputnik V [aOR = 2.90; 95% confidence interval (95% CI) = 1.40-6.04; P  = 0.004] and AstraZeneca (aOR = 5.38; 95% CI = 2.63-11.01; P  < 0.001) compared with Sinopharm. Lower odds were associated with age (aOR = 0.97; 95% CI = 0.95-0.99; P  < 0.001). Overall, 76 (95.0%) individuals assessed for the presence of SARS-CoV-2 antibody reached S1-RBD IgG antibody titers at least 1 U/ml; mean titer was 51.3 (SD = 51.07) U/ml. Higher antibody titers correlated with higher CD4 + T cells count (Rho = 0.280; P  = 0.012).

CONCLUSION

NonmRNA vaccines showed a good safety profile and adequate SARS-CoV-2 antibody responses among PWH suggesting adequate protection to SARS-CoV-2.

Living with HIV and Getting Vaccinated: A Narrative Review

After 40 years of its appearance, human immunodeficiency virus (HIV) infection remains a leading public health challenge worldwide. Since the introduction of antiretroviral treatment (ART), HIV infection has become a chronic condition, and people living with HIV could have life expectancies close to those of the general population. People with HIV often have an increased risk of infection or experience more severe morbidity following exposure to vaccine-preventable diseases. Nowadays, several vaccines are available against bacteria and viruses. However, national and international vaccination guidelines for people with HIV are heterogeneous, and not every vaccine is included. For these reasons, we aimed to perform a narrative review about the vaccinations available for adults living with HIV, reporting the most updated studies performed for each vaccine among this population. We performed a comprehensive literature search through electronic databases (Pubmed-MEDLINE and Embase) and search engines (Google Scholar). We included English peer-reviewed publications (articles and reviews) on HIV and vaccination. Despite widespread use and guideline recommendations, few vaccine trials have been conducted in people with HIV. In addition, not all vaccines are recommended for people with HIV, especially for those with low CD4 cells count. Clinicians should carefully collect the history of vaccinations and patients' acceptance and preferences and regularly check the presence of antibodies for vaccine-preventable pathogens.

Correlation between CD4 T-Cell Counts and Seroconversion among COVID-19 Vaccinated Patients with HIV: A Meta-Analysis

Objective: To evaluate the potential factors for predicting seroconversion due to the coronavirus disease 2019 (COVID-19) vaccine in people living with HIV (PLWH). Method: We searched the PubMed, Embase and Cochrane databases for eligible studies published from inception to 13th September 2022 on the predictors of serologic response to the COVID-19 vaccine among PLWH. This meta-analysis was registered with PROSPERO (CRD42022359603). Results: A total of 23 studies comprising 4428 PLWH were included in the meta-analysis. Pooled data demonstrated that seroconversion was about 4.6 times in patients with high CD4 T-cell counts (odds ratio (OR) = 4.64, 95% CI 2.63 to 8.19) compared with those with low CD4 T-cell counts. Seroconversion was about 17.5 times in patients receiving mRNA COVID-19 vaccines (OR = 17.48, 95% CI 6.16 to 49.55) compared with those receiving other types of COVID-19 vaccines. There were no differences in seroconversion among patients with different ages, gender, HIV viral load, comorbidities, days after complete vaccination, and mRNA type. Subgroup analyses further validated our findings about the predictive value of CD4 T-cell counts for seroconversion due to COVID-19 vaccines in PLWH (OR range, 2.30 to 9.59). Conclusions: The CD4 T-cell counts were associated with seroconversion in COVID-19 vaccinated PLWH. Precautions should be emphasized in these patients with low CD4 T-cell counts, even after a complete course of vaccination.

Effect of host factors and COVID-19 infection on the humoral immune repertoire in treated HIV

People with HIV (PWH) appear to be at higher risk for suboptimal pathogen responses and for worse COVID-19 outcomes, but the effects of host factors and COVID-19 on the humoral repertoire remain unclear. We assessed the antibody isotype/subclass and Fc-receptor binding Luminex arrays of non-SARS-CoV-2 and SARS-CoV-2 humoral responses among antiretroviral therapy-treated (ART-treated) PWH. Among the entire cohort, COVID-19 infection was associated with higher cytomegalovirus (CMV) responses (vs. the COVID- cohort ), potentially signifying increased susceptibility or a consequence of persistent inflammation. Among the COVID+ participants, (a) higher BMI was associated with a striking amplification of SARS-CoV-2 responses, suggesting exaggerated inflammatory responses, and (b) lower nadir CD4 was associated with higher SARS-CoV-2 IgM and FcγRIIB binding capacity, indicating poorly functioning extrafollicular and inhibitory responses. Among the COVID-19- participants, female sex, older age, and lower nadir CD4 were associated with unique repertoire shifts. In this first comprehensive assessment of the humoral repertoire in a global cohort of PWH, we identify distinct SARS-CoV-2-specific humoral immune profiles among PWH with obesity or lower nadir CD4+ T cell count, underlining plausible mechanisms associated with worse COVID-19-related outcomes in this setting. Host factors associated with the humoral repertoire in the COVID-19- cohort enhance our understanding of these important shifts among PWH.

Immunogenicity of an Additional mRNA-1273 SARS-CoV-2 Vaccination in People With HIV With Hyporesponse After Primary Vaccination

BACKGROUND

The COVIH study is a prospective coronavirus disease 2019 (COVID-19) vaccination study in 1154 people with HIV (PWH), of whom 14% showed reduced antibody levels after primary vaccination. We evaluated whether an additional vaccination boosts immune responses in these hyporesponders.

METHODS

The primary end point was the increase in antibodies 28 days after additional mRNA-1273 vaccination. Secondary end points included neutralizing antibodies, S-specific T-cell and B-cell responses, and reactogenicity.

RESULTS

Of the 66 participants, 40 previously received 2 doses ChAdOx1-S, 22 received 2 doses BNT162b2, and 4 received a single dose Ad26.COV2.S. The median age was 63 years (interquartile range [IQR], 60-66), 86% were male, and median CD4+ T-cell count was 650/μL (IQR, 423-941). The mean S1-specific antibody level increased from 35 binding antibody units (BAU)/mL (95% confidence interval [CI], 24-46) to 4317 BAU/mL (95% CI, 3275-5360) (P < .0001). Of all participants, 97% showed an adequate response and the 45 antibody-negative participants all seroconverted. A significant increase in the proportion of PWH with ancestral S-specific CD4+ T cells (P = .04) and S-specific B cells (P = .02) was observed.

CONCLUSIONS

An additional mRNA-1273 vaccination induced a robust serological response in 97% of PWH with a hyporesponse after primary vaccination. Clinical Trials Registration. EUCTR2021-001054-57-N.

Attenuated humoral responses in HIV after SARS-CoV-2 vaccination linked to B cell defects and altered immune profiles

We assessed a cohort of people living with human immunodeficiency virus (PLWH) (n = 110) and HIV negative controls (n = 64) after 1, 2 or 3 SARS-CoV-2 vaccine doses. At all timepoints, PLWH had significantly lower neutralizing antibody (nAb) titers than HIV-negative controls. We also observed a delayed development of neutralization in PLWH that was underpinned by a reduced frequency of spike-specific memory B cells (MBCs). Improved neutralization breadth was seen against the Omicron variant (BA.1) after the third vaccine dose in PLWH but lower nAb responses persisted and were associated with global MBC dysfunction. In contrast, SARS-CoV-2 vaccination induced robust T cell responses that cross-recognized variants in PLWH. Strikingly, individuals with low or absent neutralization had detectable functional T cell responses. These PLWH had reduced numbers of circulating T follicular helper cells and an enriched population of CXCR3+CD127+CD8+T cells after two doses of SARS-CoV-2 vaccination.

COVID-19 vaccine immunogenicity in people with HIV

OBJECTIVES

Many vaccines require higher/additional doses or adjuvants to provide adequate protection for people with HIV (PWH). Our objective was to compare COVID-19 vaccine immunogenicity in PWH to HIV-negative individuals.

DESIGN

In a Canadian multi-center prospective, observational cohort of PWH receiving at least two COVID-19 vaccinations, we measured vaccine-induced immunity at 3 and 6 months post 2nd and 1-month post 3rd doses.

METHODS

The primary outcome was the percentage of PWH mounting vaccine-induced immunity [co-positivity for anti-IgG against SARS-CoV2 Spike(S) and receptor-binding domain proteins] 6 months post 2nd dose. Univariable and multivariable logistic regressions were used to compare COVID-19-specific immune responses between groups and within subgroups.

RESULTS

Data from 294 PWH and 267 controls were analyzed. Immunogenicity was achieved in over 90% at each time point in both groups. The proportions of participants achieving comparable anti-receptor-binding domain levels were similar between the group at each time point. Anti-S IgG levels were similar by group at month 3 post 2nd dose and 1-month post 3rd dose. A lower proportion of PWH vs. controls maintained vaccine-induced anti-S IgG immunity 6 months post 2nd dose [92% vs. 99%; odds ratio: 0.14 (95% confidence interval: 0.03, 0.80; P = 0.027)]. In multivariable analyses, neither age, immune non-response, multimorbidity, sex, vaccine type, or timing between doses were associated with reduced IgG response.

CONCLUSION

Vaccine-induced IgG was elicited in the vast majority of PWH and was overall similar between groups. A slightly lower proportion of PWH vs. controls maintained vaccine-induced anti-S IgG immunity 6 months post 2nd dose demonstrating the importance of timely boosting in this population.

Attenuated humoral responses in HIV infection after SARS-CoV-2 vaccination are linked to global B cell defects and cellular immune profiles

People living with HIV (PLWH) on suppressive antiretroviral therapy (ART) can have residual immune dysfunction and often display poorer responses to vaccination. We assessed in a cohort of PLWH (n=110) and HIV negative controls (n=64) the humoral and spike-specific B-cell responses following 1, 2 or 3 SARS-CoV-2 vaccine doses. PLWH had significantly lower neutralizing antibody (nAb) titers than HIV-negative controls at all studied timepoints. Moreover, their neutralization breadth was reduced with fewer individuals developing a neutralizing response against the Omicron variant (BA.1) relative to controls. We also observed a delayed development of neutralization in PLWH that was underpinned by a reduced frequency of spike-specific memory B cells (MBCs) and pronounced B cell dysfunction. Improved neutralization breadth was seen after the third vaccine dose in PLWH but lower nAb responses persisted and were associated with global, but not spike-specific, MBC dysfunction. In contrast to the inferior antibody responses, SARS-CoV-2 vaccination induced robust T cell responses that cross-recognized variants in PLWH. Strikingly, a subset of PLWH with low or absent neutralization had detectable functional T cell responses. These individuals had reduced numbers of circulating T follicular helper cells and an enriched population of CXCR3 + CD127 + CD8 + T cells after two doses of SARS-CoV-2 vaccination, which may compensate for sub-optimal serological responses in the event of infection. Therefore, normalisation of B cell homeostasis could improve serological responses to vaccines in PLWH and evaluating T cell immunity could provide a more comprehensive immune status profile in these individuals and others with B cell imbalances.

Immunogenicity and efficacy of COVID-19 vaccines in people living with HIV: a systematic review and meta-analysis

OBJECTIVES

Available data show that COVID-19 vaccines may be less effective in people living with HIV (PLWH) who are at increased risk for severe COVID-19. This meta-analysis aimed to compare the immunogenicity and efficacy of COVID-19 vaccines in PLWH with healthy individuals.

METHODS

Pubmed/Medline, EMBASE, and the Cochrane Library were searched. Risk ratios of seroconversion were separately pooled using random-effects meta-analysis, and a systematic review without meta-analysis of SARS-CoV-2 antibody titer levels was performed after the first and second doses of a COVID-19 vaccine.

RESULTS

A total of 22 studies with 6522 subjects met the inclusion criteria. After the first vaccine dose, seroconversion in PLWH was comparable to that in healthy individuals. After a second dose, seroconversion was slightly lower in PLWH compared with healthy controls, and antibody titers did not seem to be significantly affected or reduced among participants of both groups.

CONCLUSION

COVID-19 vaccines show favorable immunogenicity and efficacy in PLWH. A second dose is associated with consistently improved seroconversion, although it is slightly lower in PLWH than in healthy individuals. Additional strategies, such as a booster vaccination with messenger RNA COVID-19 vaccines, might improve seroprotection for these patients.

SARS-CoV-2 and Influenza Vaccines in People with Excessive Body Mass-A Narrative Review

In the face of a growing number of overweight people and two widely known viral diseases, SARS-CoV-2 and influenza, it is crucial to be aware of the impact of excess body weight on immunisation against these diseases. The aim of this review is to show the effectiveness of SARS-CoV-2 and influenza vaccines in overweight and obese patients. Excessive adipose tissue releases cytokines and maintains local hypoxia, which causes persistent low-grade inflammation. These factors make excess body mass patients' immune systems weaker. Under such conditions, the humoral response becomes less efficient, leading to a weakened ability to fight against infection and an increased risk of developing lower antibody titres. Vaccines help to reduce morbidity both in normal-weight and excess body mass people, although most studies show that patients with higher BMI tend to lose the antibodies produced more quickly. It is shown that the most effective vaccines (in terms of preventing the infection and potential post-illness complications) are the BNT162b2 vaccine against SARS-CoV-2 and the inactivated influenza vaccine against influenza among both obese and non-obese subjects.

Immunogenicity and reactogenicity of SARS-CoV-2 vaccines in people living with HIV in the Netherlands: A nationwide prospective cohort study

BACKGROUND

Vaccines can be less immunogenic in people living with HIV (PLWH), but for SARS-CoV-2 vaccinations this is unknown. In this study we set out to investigate, for the vaccines currently approved in the Netherlands, the immunogenicity and reactogenicity of SARS-CoV-2 vaccinations in PLWH.

METHODS AND FINDINGS

We conducted a prospective cohort study to examine the immunogenicity of BNT162b2, mRNA-1273, ChAdOx1-S, and Ad26.COV2.S vaccines in adult PLWH without prior COVID-19, and compared to HIV-negative controls. The primary endpoint was the anti-spike SARS-CoV-2 IgG response after mRNA vaccination. Secondary endpoints included the serological response after vector vaccination, anti-SARS-CoV-2 T-cell response, and reactogenicity. Between 14 February and 7 September 2021, 1,154 PLWH (median age 53 [IQR 44-60] years, 85.5% male) and 440 controls (median age 43 [IQR 33-53] years, 28.6% male) were included in the final analysis. Of the PLWH, 884 received BNT162b2, 100 received mRNA-1273, 150 received ChAdOx1-S, and 20 received Ad26.COV2.S. In the group of PLWH, 99% were on antiretroviral therapy, 97.7% were virally suppressed, and the median CD4+ T-cell count was 710 cells/μL (IQR 520-913). Of the controls, 247 received mRNA-1273, 94 received BNT162b2, 26 received ChAdOx1-S, and 73 received Ad26.COV2.S. After mRNA vaccination, geometric mean antibody concentration was 1,418 BAU/mL in PLWH (95% CI 1322-1523), and after adjustment for age, sex, and vaccine type, HIV status remained associated with a decreased response (0.607, 95% CI 0.508-0.725, p < 0.001). All controls receiving an mRNA vaccine had an adequate response, defined as >300 BAU/mL, whilst in PLWH this response rate was 93.6%. In PLWH vaccinated with mRNA-based vaccines, higher antibody responses were predicted by CD4+ T-cell count 250-500 cells/μL (2.845, 95% CI 1.876-4.314, p < 0.001) or >500 cells/μL (2.936, 95% CI 1.961-4.394, p < 0.001), whilst a viral load > 50 copies/mL was associated with a reduced response (0.454, 95% CI 0.286-0.720, p = 0.001). Increased IFN-γ, CD4+ T-cell, and CD8+ T-cell responses were observed after stimulation with SARS-CoV-2 spike peptides in ELISpot and activation-induced marker assays, comparable to controls. Reactogenicity was generally mild, without vaccine-related serious adverse events. Due to the control of vaccine provision by the Dutch National Institute for Public Health and the Environment, there were some differences between vaccine groups in the age, sex, and CD4+ T-cell counts of recipients.

CONCLUSIONS

After vaccination with BNT162b2 or mRNA-1273, anti-spike SARS-CoV-2 antibody levels were reduced in PLWH compared to HIV-negative controls. To reach and maintain the same serological responses as HIV-negative controls, additional vaccinations are probably required.

TRIAL REGISTRATION

The trial was registered in the Netherlands Trial Register (NL9214). https://www.trialregister.nl/trial/9214.

SARS-CoV-2 immunity and vaccine strategies in people with HIV

Current severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines, based on the ancestral Wuhan strain, were developed rapidly to meet the needs of a devastating global pandemic. People living with Human Immunodeficiency Virus (PLWH) have been designated as a priority group for SARS-CoV-2 vaccination in most regions and varying primary courses (two- or three-dose schedule) and additional boosters are recommended depending on current CD4+ T cell count and/or detectable HIV viraemia. From the current published data, licensed vaccines are safe for PLWH, and stimulate robust responses to vaccination in those well controlled on antiretroviral therapy and with high CD4+ T cell counts. Data on vaccine efficacy and immunogenicity remain, however, scarce in PLWH, especially in people with advanced disease. A greater concern is a potentially diminished immune response to the primary course and subsequent boosters, as well as an attenuated magnitude and durability of protective immune responses. A detailed understanding of the breadth and durability of humoral and T cell responses to vaccination, and the boosting effects of natural immunity to SARS-CoV-2, in more diverse populations of PLWH with a spectrum of HIV-related immunosuppression is therefore critical. This article summarizes focused studies of humoral and cellular responses to SARS-CoV-2 infection in PLWH and provides a comprehensive review of the emerging literature on SARS-CoV-2 vaccine responses. Emphasis is placed on the potential effect of HIV-related factors and presence of co-morbidities modulating responses to SARS-CoV-2 vaccination, and the remaining challenges informing the optimal vaccination strategy to elicit enduring responses against existing and emerging variants in PLWH.

Immune response and safety to inactivated COVID-19 vaccine: a comparison between people living with HIV and HIV-naive individuals

BACKGROUND

Multi-types COVID-19 vaccines have shown safety and efficacy against COVID-19 in adults. Although current guidelines encourage people living with HIV (PLWH) to take COVID-19 vaccines, whether their immune response to COVID-19 vaccines is distinct from HIV-free individuals is still unclear.

METHODS

Between March to June 2021, 48 PLWH and 40 HNC, aged 18 to 59 years, were enrolled in the study in Wuchang district of Wuhan city. All of them received inactivated COVID-19 vaccine (Sinopharm, WIBP-CorV, Wuhan Institute of Biological Products Co. Ltd) at day 0 and the second dose at day 28. The primary safety outcome was the combined adverse reactions within 7 days after each injection. The primary immunogenicity outcomes were SARS-CoV-2 neutralizing antibodies (nAbs) responses by chemiluminescence and total specific IgM and IgG antibodies responses by ELISA and colloidal gold at baseline (day 0), day 14, day 28, day 42, and day 70.

RESULTS

In total, the study included 46 PLWH and 38 HNC who finished 70 days' follow-up. The frequency of adverse reactions to the first and second dose was not different between PLWH (30% and 11%) vs. HNC (32% and 24%). NAbs responses among PLWH peaked at day 70, while among HNC peaked at day 42. At day 42, the geometric mean concentration (GMC) and seroconversion rate of nAbs among PLWH were 4.46 binding antibody units (BAU)/mL (95% CI 3.18-5.87) and 26% (95% CI 14-41), which were lower than that among HNC [GMC (18.28 BAU/mL, 95% CI 10.33-32.33), seroconversion rate (63%, 95% CI 44-79)]. IgG responses among both PLWH and HNC peaked at day 70. At day 70, the geometric mean ELISA units (GMEU) and seroconversion rate of IgG among PLWH were 0.193 ELISA units (EU)/mL (95% CI 0.119-0.313) and 51% (95% CI 34-69), which was lower than that among HNC [GMEU (0.379 EU/mL, 95% CI 0.224-0.653), seroconversion rate (86%, 95% CI 64-97)]. There were no serious adverse events.

CONCLUSIONS

Early humoral immune response to the inactivated COVID-19 vaccine was weaker and delayed among the PLWH population than that among HNC. This observation remained consistent regardless of a high CD4 count with effective antiretroviral therapy.

High seroprotection rates and geometric mean titre increases after repeated annual influenza vaccinations in a cohort of HIV-infected adults in Austria

INTRODUCTION

Vaccination against seasonal influenza is recommended for all HIV-infected persons. Few data have been reported on the effect of repeated annual vaccination in this population.

METHODS

We measured haemagglutination inhibition antibody responses and investigated seroprotection rates in 344 HIV-infected adults before and 12 weeks after influenza vaccination with a trivalent subunit vaccine.

RESULTS

68.3% of patients were male, the median age was 45 years. 83.7% had a viral load < 50 copies/mL. The median CD4 count was 604/µL. 304 patients (88.4%) had received influenza vaccinations in previous years. Seroprotection rates for A/H1N1 and B were over 90% in all age groups before vaccination and close to 100% after vaccination. For A/H3N2, seroprotection rates were lowest in individuals below 30 years both before and after vaccination (22.2% and 50.0%) and higher in older age groups (48.4% and 83.9% in people over 60 years). GMT fold increases were not significantly different across the age groups (3.0 to 4.2, p = 0.425). Previous influenza vaccinations were associated with higher seroprotection rates before and after vaccination (62.2% and 84.2% in patients with 8 or more previous vaccinations vs. 15.0% and 57.5% without previous vaccinations, respectively). Individuals with detectable viral load, elevated immune activation (urine neopterin ≥ 250 µmol/mol creatinine), and higher CD4 nadir (≥200 cells/µL) showed a trend towards inferior immune responses to vaccination, whereas gender and CD4 count did not have an effect.

CONCLUSION

The lower seroprotection rates observed in younger individuals may be explained by the higher proportion of patients without HIV treatment and with fewer previous encounters with influenza strains. Good seroprotection rates can be achieved in elderly HIV-infected patients and after repeated annual vaccinations.

Influenza Vaccination Results in Differential Hemagglutinin Stalk-Specific Fc-Mediated Functions in Individuals Living With or Without HIV

Influenza virus hemagglutinin (HA) stalk-specific antibodies have been shown to potently induce Fc-mediated effector functions which are important in protection from disease. In placebo-controlled maternal influenza (MatFlu) vaccination trials of pregnant women living with or without HIV, reduced risk of influenza illness was associated with high HA stalk antibody titers following trivalent inactivated vaccination (TIV). However, the mechanisms of immunity conferred by the HA stalk antibodies were not well understood. Here, we investigated HA stalk-specific Fc effector functions including antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent complement deposition (ADCD), and FcγRIIa and FcγRIIIa binding in response to seasonal influenza vaccination. These were measured pre- and 1-month post-vaccination in 141 HIV-uninfected women (67 TIV and 74 placebo recipients) and 119 women living with HIV (WLWH; 66 TIV and 53 placebo recipients). In contrast to HIV-uninfected women, where HA stalk-specific ADCP and FcγRIIa binding were significantly boosted, WLWH showed no increase in response to vaccination. HA stalk-specific ADCC potential and FcγRIIIa binding were not boosted regardless of HIV status but were higher in WLWH compared with HIV-uninfected women prior to vaccination. HA stalk-specific ADCD was significantly increased by vaccination in all women, but was significantly lower in the WLWH both pre- and post- vaccination. Co-ordination between HA stalk-specific ADCP and ADCD in WLWH was improved by vaccination. Fc polyfunctionality was enhanced by vaccination in HIV-uninfected women and driven by the HA stalk antibody titers. However, in the WLWH, higher pre-vaccination Fc polyfunctionality was maintained post-vaccination but was decoupled from titer. Overall, we showed differential regulation of Fc effector HA stalk responses, suggesting that HIV infection results in unique humoral immunity in response to influenza vaccination, with relevance for future strategies that aim to target the HA stalk in this population.

Distinct Molecular Signatures of Aging in Healthy and HIV-Infected Individuals

BACKGROUND

Virally suppressed chronic HIV-infected individuals on antiretroviral therapy experience similar immune impairments as HIV-uninfected elderly. However, they manifest symptoms of premature immune aging such as suboptimal responses to vaccination at a younger age. Mechanisms underlying premature immune aging are unclear.

SETTING

The study site was University of Miami Miller School of Medicine.

METHODS

In this study, we aimed to identify molecular signatures of aging in HIV-infected (HIV) individuals compared with age-matched healthy control (HC) participants. Transcriptomic profiles of peripheral blood mononuclear cells collected cross-sectionally from study participants were evaluated using RNA sequencing, and genes and pathways associated with age and HIV status were identified and compared between study groups. Generalized linear modeling was used to identify transcriptional signatures associated with age.

RESULTS

Despite that fewer differentially expressed genes between young (<40 yrs) and old (>59 yrs) were observed in the HIV group, metabolic and innate immune activation pathways were associated with increasing age in both HIV and HC. Age was also associated with pathways involved with T-cell immune activation in HC and with interferon signaling pathways in HIV. We observed signs of precocious immune aging at the transcriptional level in HIV and defined a transcriptional perturbation associated with innate immunity and glucose metabolism induced by aging in both HC and HIV.

CONCLUSION

In this study, we identified distinct molecular signatures predictive of age in HIV versus HC, which suggest precocious immune aging in HIV. Overall, our results highlight the molecular pathways of immune aging in both HC and HIV that may be targeted for additional mechanistic insights or in a therapeutic setting.

A Longitudinal Analysis of SARS-CoV-2 Antibody Responses Among People With HIV

Background

The concentration and duration of antibodies (Ab) to SARS-CoV-2 infection predicts the severity of the disease and the clinical outcomes. Older people and those with HIV have impaired immune responses, worse outcomes after SARS-CoV-2 infection, and lower antibody responses after viral infection and vaccination. This study evaluated an Ab response to SARS-CoV-2 in people with HIV (PWH) and without HIV (HIV-) and its association with age.

Methods

A total of 23 COVID+PWH and 21 COVID+HIV- participants were followed longitudinally for 6 months post-mild COVID-19. Immunoglobin G (IgG) and immunoglobin M (IgM) Ab responses were measured by an in-house developed ELISA. Time points and HIV status interaction were analyzed using Poisson generalized estimating equations, and correlations were analyzed using non-parametric tests.

Results

Median age in PWH was 55 years with 28.6% women, while in the HIV- group was 36 years with 60.9% women. The mean time from COVID-19 diagnosis to study enrollment was 16 days for PWH and 11 days for HIV-. The mean CD4+ T-cell count/μl for PWH was 772.10 (±365.21). SARS-CoV-2 IgM and IgG were detected at all time points and Ab response levels did not differ by HIV status (p > 0.05). At entry, age showed a weak direct association with IgG responses (ρ = 0.44, p < 0.05) in HIV- but did not show any association in PWH. Similar associations between age, IgG, and HIV status emerged at day 14 (T1; ρ = 0.50, p < 0.05), 3 months (T3; ρ = 0.50, p < 0.05), and 6 months visit (T4; ρ = 0.78, p < 0.05) in the HIV- group.

Conclusion

The Ab responses in the 6-month post-SARS-CoV-2 infection did not differ by HIV status, though a positive association was found between age and Ab response in older PWH. Results suggest that immune protection and vaccine responses are similar for PWH than for those without HIV infection.

Age Associated Microbiome and Microbial Metabolites Modulation and Its Association With Systemic Inflammation in a Rhesus Macaque Model

Aging is associated with declining immunity and inflammation as well as alterations in the gut microbiome with a decrease of beneficial microbes and increase in pathogenic ones. The aim of this study was to investigate the age associated gut microbiome in relation to immunologic and metabolic profile in a non-human primate (NHP) model. 12 geriatric (age 19-24 years) and 4 young adult (age 3-4 years) Rhesus macaques were included in this study. Immune cell subsets were characterized in peripheral blood mononuclear cells (PBMC) by flow cytometry and plasma cytokines levels were determined by bead based multiplex cytokine analysis. Stool samples were collected by ileal loop and investigated for microbiome analysis by shotgun metagenomics. Serum, gut microbial lysate, and microbe-free fecal extract were subjected to metabolomic analysis by mass-spectrometry. Our results showed that the gut microbiome in geriatric animals had higher abundance of Archaeal and Proteobacterial species and lower Firmicutes than the young adults. Highly abundant microbes in the geriatric animals showed a direct association with plasma biomarkers of inflammation and immune activation such as neopterin, CRP, TNF, IL-2, IL-6, IL-8 and IFN-γ. Significant enrichment of metabolites that contribute to inflammatory and cytotoxic pathways was observed in serum and feces of geriatric animals compared to the young adults. We conclude that aging NHP undergo immunosenescence and age associated alterations in the gut microbiome that has a distinct metabolic profile. Aging NHP can serve as a model for investigating the relationship of the gut microbiome to particular age-associated comorbidities and for strategies aimed at modulating the microbiome.

Immunological age prediction in HIV-infected, ART-treated individuals

Anti-retroviral therapy (ART) improves life expectancy in people living with HIV (PWH), but it remains unclear how chronic HIV infection affects normal aging of the immune system. Plasma cell-free protein expression and immune phenotypes were assessed in blood from ART treated PWH (19-77yrs, n = 106) and age-matched, HIV-negative controls (HC, n = 103). Using univariate spearman correlation, we identified 277 and 491 age-associated parameters out of a total 1,357 in HC and PWH, respectively. PWH exhibited shared and distinct age-associated immune profiles compared to HC highlighting the effect of HIV infection on immunological aging. Our analysis resulted in an 8-parameter, plasma-detectable inflammatory index that correlated with chronological age of all study participants but was higher overall in PWH. Additionally, predictive modeling for age in HC participants and age-associated parameters generated a 25-parameter signature, IMAP-25, with 70% and 53% accuracy in HC and PWH, respectively. Applying the IMAP-25 signature to immunological data from PWH revealed accelerated aging in PWH by 5.6 yrs. Overall, our results demonstrate that immune signatures, easily monitored in human blood samples, can be used as an indicator of one’s ‘immunological age’ during ART-treated HIV infection and can be applied to other disease states that affect the immune system.

Pressing Questions and Challenges in the HIV-1 and SARS-CoV-2 Syndemic

Since emerging into the human population in late 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has reached across the globe to infect >80 million people. The coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 can range in severity from mild and asymptomatic to severe and fatal. Identifying risk factors for adverse outcomes in COVID-19 is a major challenge. In the context of the existing HIV-1 pandemic, whether COVID-19 disproportionately burdens people living with HIV-1 infection (PLWH) is unclear. The following discussion highlights pressing questions and challenges in the HIV-1 and SARS-CoV-2 syndemic, including (i) age, sex, and race as drivers of COVID-19 severity; (ii) whether chronic inflammation common in PLWH influences immune response; (iii) whether disease severity and trajectory models for COVID-19 ought to be calibrated for PLWH; (iv) vaccine considerations, and finally, (v) long-term health outcomes in PLWH that are further burdened by coinfection with SARS-CoV-2.

Cytomegalovirus as an Uninvited Guest in the Response to Vaccines in People Living with HIV

In stark contrast to the rapid development of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an effective human immunodeficiency virus (HIV) vaccine is still lacking. Furthermore, despite virologic suppression and CD4 T-cell count normalization with antiretroviral therapy (ART), people living with HIV (PLWH) still exhibit increased morbidity and mortality compared to the general population. Such differences in health outcomes are related to higher risk behaviors, but also to HIV-related immune activation and viral coinfections. Among these coinfections, cytomegalovirus (CMV) latent infection is a well-known inducer of long-term immune dysregulation. Cytomegalovirus contributes to the persistent immune activation in PLWH receiving ART by directly skewing immune response toward itself, and by increasing immune activation through modification of the gut microbiota and microbial translocation. In addition, through induction of immunosenescence, CMV has been associated with a decreased response to infections and vaccines. This review provides a comprehensive overview of the influence of CMV on the immune system, the mechanisms underlying a reduced response to vaccines, and discuss new therapeutic advances targeting CMV that could be used to improve vaccine response in PLWH.

Vaccine responses in ageing and chronic viral infection

Over the last few decades, changing population demographics have shown that there are a growing number of individuals living past the age of 60. With this expanding older population comes an increase in individuals that are more susceptible to chronic illness and disease. An important part of maintaining health in this population is through prophylactic vaccination, however, there is growing evidence that vaccines may be less effective in the elderly. Furthermore, with the success of anti-viral therapies, chronic infections such as HIV are becoming increasingly prevalent in older populations and present a relatively unstudied population with respect to the efficacy of vaccination. Here we will examine the evidence for age-associated reduction in antibody and cellular responsiveness to a variety of common vaccines and investigate the underlying causes attributed to this phenomenon, such as inflammation and senescence. We will also discuss the impact of chronic viral infections on immune responses in both young and elderly patients, particularly those living with HIV, and how this affects vaccinations in these populations.

Transcriptional and Immunologic Correlates of Response to Pandemic Influenza Vaccine in Aviremic, HIV-Infected Children

People living with HIV (PWH) often exhibit poor responses to influenza vaccination despite effective combination anti-retroviral (ART) mediated viral suppression. There exists a paucity of data in identifying immune correlates of influenza vaccine response in context of HIV infection that would be useful in improving its efficacy in PWH, especially in younger individuals. Transcriptomic data were obtained by microarray from whole blood isolated from aviremic pediatric and adolescent HIV-infected individuals (4-25 yrs) given two doses of Novartis/H1N1 09 vaccine during the pandemic H1N1 influenza outbreak. Supervised clustering and gene set enrichment identified contrasts between individuals exhibiting high and low antibody responses to vaccination. High responders exhibited hemagglutination inhibition antibody titers >1:40 post-first dose and 4-fold increase over baseline. Baseline molecular profiles indicated increased gene expression in metabolic stress pathways in low responders compared to high responders. Inflammation-related and interferon-inducible gene expression pathways were higher in low responders 3 wks post-vaccination. The broad age range and developmental stage of participants in this study prompted additional analysis by age group (e.g. <13yrs and ≥13yrs). This analysis revealed differential enrichment of gene pathways before and after vaccination in the two age groups. Notably, CXCR5, a homing marker expressed on T follicular helper (Tfh) cells, was enriched in high responders (>13yrs) following vaccination which was accompanied by peripheral Tfh expansion. Our results comprise a valuable resource of immune correlates of vaccine response to pandemic influenza in HIV infected children that may be used to identify favorable targets for improved vaccine design in different age groups.

Characterization of HIV-1 Envelope V3 Region Sequences from Virologically Controlled HIV-Infected Older Patients on Long Term Antiretroviral Therapy

Although many HIV-infected patients have attained older age owing to the success of antiretroviral therapy (ART) in controlling viremia and increasing CD4 T cell counts, HIV continues to persist in several target cells. We have characterized 514 HIV-1 envelope V3 region sequences (94-96 amino acids [aa]) from 25 HIV-infected older patients' peripheral blood mononuclear cell DNA on long-term ART with controlled viremia (undetectable viral load) and improved CD4 T cell counts. Phylogenetic analysis revealed that the V3 region sequences of each patient formed distinct clusters that were well separated and discriminated from other patients' sequences. The coding potential of the V3 region, including several patient-specific amino acid motifs and functional domains, including the two cysteines sandwiching the V3 loop, the central GPGR motif with variation at one position in some sequences, the base GDIR motif, and the N-glycosylation sites were generally conserved. The patients' V3 region sequences contained amino acid motifs conferring affinity mostly for CCR5 coreceptor, suggesting R5 phenotype. There was a low degree of heterogeneity and lower estimates of genetic diversity in all 25 patients' V3 region sequences. Twelve of 25 patients' V3 region sequences were found to be under positive selection pressure. Analysis of the several cytotoxic T lymphocytes (CTL) epitopes showed variation, whereas some of known neutralizing antibodies (nAbs) epitopes showed conservation in patients' V3 region sequences. In conclusion, a low degree of genetic variability and maintenance of functional domains with R5 phenotypes, and variation in CTL and conservation of nAb epitopes were the hallmarks of V3 region sequences from our 25 virologically controlled HIV-infected older patients on long-term ART.

Distinct Features of Germinal Center Reactions in Macaques Infected by SIV or Vaccinated with a T-Dependent Model Antigen

B-cell follicles constitute large reservoirs of infectious HIV/SIV associated to follicular dendritic cells and infecting follicular helper (TFH) and regulatory (TFR) T-cells in germinal centers (GCs). Thus, follicular and GC B-cells are persistently exposed to viral antigens. Despite recent development of potent HIV immunogens, numerous questions are still open regarding GC reaction during early HIV/SIV infection. Here, we dissect the dynamics of B- and T-cells in GCs of macaques acutely infected by SIV (Group SIV+) or vaccinated with Tetanus Toxoid (Group TT), a T-dependent model antigen. Systemic inflammation and mobilization of antigen-presenting cells in inguinal lymph nodes and spleen are lower in Group TT than in Group SIV+. Despite spleen GC reaction of higher magnitude in Group SIV+, the development of protective immunity could be limited by abnormal helper functions of TFH massively polarized into TFH1-like cells, by inflammation-induced recruitment of fCD8 (either regulatory or cytotoxic) and by low numbers of TFR limiting TFH/TFR competition for high affinity B-cells. Increased GC B-cells apoptosis and accumulation of CD21lo memory B-cells, unable to further participate to GC reaction, likely contribute to eliminate SIV-specific B-cells and decrease antibody affinity maturation. Surprisingly, functional GCs and potent TT-specific antibodies develop despite low levels of CXCL13.

Impact of repeated yearly vaccination on immune responses to influenza vaccine in an elderly population

BACKGROUND

The effectiveness of repeated vaccination for seasonal influenza remains controversial. Here, we measured antibody responses to the influenza virus (A/H1N1, A/H3N2 and B) in a closed cohort of older participants vaccinated against influenza virus in each of 5 consecutive years.

METHODS

One hundred and 11 volunteers aged >61 years were vaccinated subcutaneously with 1 dose (0.5 ml) of inactivated influenza vaccine as recommended by the World Health Organization from the 2005-2006 season through the 2009-2010 season. Hemagglutination inhibition (HI) antibody titers were determined.

RESULTS

HI antibody titers against all 3 virus strains were significantly higher at 4 weeks after vaccination than at a time point prior to vaccination in each of the 5 seasons (P < .01); HI antibody titers were detected at the original prevaccination levels just prior to re-vaccination the following year. Sero-protection and HI antibody titers at 4 weeks after vaccination were similar against all influenza strains and during most of the 5 seasons evaluated. Vaccine strain changes were associated with specific immune responses in 9 of 12 (75%) intervals.

CONCLUSIONS

Taken together, our results suggest that annual vaccination is necessary to maintain humoral immunity for the elderly population. Furthermore, our findings revealed that annual seasonal vaccination was not associated with reduced vaccine effectiveness, and that the reformation of the vaccine resulted in amplified immune responses among those undergoing yearly vaccination in the elderly population.

Immunity to acute virus infections with advanced age

New infections in general, and new viral infections amongst them, represent a serious challenge to an older organism. This review discusses the age-related alterations in responsiveness to infection from the standpoint of virus:host relationship and the host physiological whole-organism and specific immune response to the virus. Changes with age in the innate and adaptive immune system homeostasis and function are reviewed briefly. This is followed by a review of specific alterations and defects in the response of older organisms (chiefly mice and humans) to acute (particularly emerging and re-emerging) viral infections, with a very brief summary of the response to latent persistent infections. Finally, we provide a brief summary of the perspectives for possible interventions to enhance antiviral immunity.

Implications of Immune Checkpoint Expression During Aging in HIV-Infected People on Antiretroviral Therapy

Immune checkpoint molecules (ICMs) regulate T cell responses. In chronic viral infections and cancer, where antigens can persistently stimulate the immune system, ICMs can serve as a barrier to effective immune responses. The role of ICMs in the setting of systemic low-grade inflammation as in aging and antiretroviral therapy (ART)-suppressed HIV infection is not known. In this study, we made use of stored samples from the FLORAH cohort of HIV-infected ART-suppressed adults (age range 19-77 years.) and age-matched HIV-uninfected controls. We measured the expression levels of ICMs: PD-1, LAG-3, TIGIT, TIM-3, and 2B4 on resting CD4 and CD8 T cells and maturation subsets. To determine how expression of these molecules can affect T cell function, we stimulated peripheral blood mononuclear cell with HIV Gag or p09/H1N1 antigen and performed intracellular cytokine staining by multiparameter flow cytometry. ICMs were expressed at higher levels in CD8 compared with CD4. PD-1 was the only molecule that remained significantly higher in HIV-infected individuals compared with controls. LAG-3 expression increased with age in CD4 and CD8 T cells. 2B4 expression on CD8 T cells was negatively associated with IL-2 production but showed no effect on CD4 T cell function. TIM-3 expression was negatively associated with IL-21 production in CD4 and CD8 T cells and also negatively correlated with flu vaccine responses in HIV-negative individuals. Taken altogether, this study demonstrates the marked variation in ICM expression in T cells among adults and sheds light on the biology of these molecules and their effects on antigen-specific T cell functions. Overall, our results point to TIM-3 as a potential biomarker for immune function in HIV⁺ individuals on ART.

Pathogenesis of Aging and Age-related Comorbidities in People with HIV: Highlights from the HIV ACTION Workshop

People with HIV (PWH) experience accentuated biological aging, as defined by markers of inflammation, immune dysfunction, and the epigenetic clock. They also have an elevated risk of multiple age-associated comorbidities. To discuss current knowledge, research gaps, and priorities in aging and age-related comorbidities in treated HIV infection, the NIH program staff organized a workshop held in Bethesda, Maryland in September 2019. This review article describes highlights of discussions led by the Pathogenesis/Basic Science Research working group that focused on three high priority topics: immunopathogenesis; the microbiome/virome; and aging and senescence. We summarize knowledge in these fields and describe key questions for research on the pathogenesis of aging and age-related comorbidities in PWH. Understanding the drivers and mechanisms underlying accentuated biological aging is a high priority that will help identify potential therapeutic targets to improve healthspan in older PWH.

Recent advances in influenza vaccines

Seasonal influenza remains a major public health problem, responsible for hundreds of thousands of deaths every year, mostly of elderly people. Despite the wide availability of vaccines, there are multiple problems decreasing the effectiveness of vaccination programs. These include viral variability and hence the requirement to match strains by estimating which will become prevalent each season, problems associated with vaccine and adjuvant production, and the route of administration as well as the perceived lower vaccine efficiency in older adults. Clinical protection is still suboptimal for all of these reasons, and vaccine uptake remains too low in most countries. Efforts to improve the effectiveness of influenza vaccines include developing universal vaccines independent of the circulating strains in any particular season and stimulating cellular as well as humoral responses, especially in the elderly. This commentary assesses progress over the last 3 years towards achieving these aims. Since the beginning of 2020, an unprecedented international academic and industrial effort to develop effective vaccines against the new coronavirus SARS-CoV-2 has diverted attention away from influenza, but many of the lessons learned for the one will synergize with the other to mutual advantage. And, unlike the SARS-1 epidemic and, we hope, the SARS-CoV-2 pandemic, influenza will not be eliminated and thus efforts to improve influenza vaccines will remain of crucial importance.

Early Insights into COVID-19 in Persons Living with HIV and Cardiovascular Manifestations

Persons living with HIV-1 (PLHIV) are at increased risk of cardiovascular complications in part due to the persistent inflammatory state despite viral suppression. SARS-CoV-2, the virus causing COVID-19, was declared a pandemic virus in March 2020, and caused over 30 million cases and 900,000 deaths worldwide to date. Individuals with COVID-19 are manifesting acute cardiovascular complications because of the inflammatory response associated with SARS-CoV-2 infection. It is not yet known whether having COVID-19 in the context of ongoing HIV-1 infection results in worse cardiovascular complications than in PLHIV who have not had COVID-19 infection. In this review, the potential for exacerbated cardiovascular manifestations in persons coinfected with HIV-1 and COVID-19 is considered.

Harvard HIV and Aging Workshop: Perspectives and Priorities from Claude D. Pepper Centers and Centers for AIDS Research

People aging with HIV (PAWH) infection experience greater impairments in physical and cognitive function, in addition to higher rates of peripheral comorbid conditions (e.g., renal failure, diabetes, bone fracture, hypertension, cardiovascular disease, polypharmacy, and multimorbidity). While multifactorial drivers, including HIV infection itself, antiretroviral therapy-related toxicities, disparities in care, and biobehavioral factors, likely contribute, there remains an overarching question as to what are the relevant age-related mechanisms and models that could inform interventions that promote health span and life span in PAWH? This workshop was convened to hear from experts on the biology of aging and HIV researchers studying PAWH to focus on advancing investigations at the interface of HIV and Aging. In this study, we summarize the discussions from the Harvard Center for AIDS Research and Boston Claude D. Pepper cosponsored workshop on HIV and Aging, which took place in October 2018.

Responses to Quadrivalent Influenza Vaccine Reveal Distinct Circulating CD4+CXCR5+ T Cell Subsets in Men Living with HIV

T cell help for B cells may be perturbed in people living with HIV (PLWH), even when HIV is suppressed, as evidenced by reports of suboptimal responses to influenza vaccination. We investigated cT_FH responses to the 2017-18 inactivated quadrivalent influenza vaccine (QIV) in men living with antiretroviral therapy (ART)-suppressed HIV infection who were treated in the early or chronic phase of infection, and control subjects. Here we show that seroprotective antibody responses in serum and oral fluid correlated with cT_FH activation and were equivalent in all three groups, irrespective of when ART was started. These responses were attenuated in those reporting immunisation with influenza vaccine in the preceding three years, independent of HIV infection. Measurement of influenza-specific IgG in oral fluid was closely correlated with haemagglutination inhibition titre. T-SNE and two-dimensional analysis revealed a subset of CD4⁺CXCR3⁺CXCR5⁺ cT_FH activated at one week after vaccination. This was distinguishable from cTFH not activated by vaccination, and a rare, effector memory CD4⁺CXCR5^hiCD32^hi T cell subset. The data support the use of QIV for immunisation of PLWH, reveal distinct circulating CD4⁺CXCR5⁺ T cell subsets and demonstrate oral fluid sampling for influenza-specific IgG is an alternative to phlebotomy.

Current Challenges and Solutions in Research and Clinical Care of Older Persons Living with HIV: Findings Presented at the 9th International Workshop on HIV and Aging

In the era of effective antiretroviral therapy, the number of older people with HIV (PWH) is increasing, and those aging with HIV are experiencing an increasing burden of age-associated comorbidities. Life expectancy among older PWH is approaching that of demographically comparable HIV-uninfected (HIV-) adults. With this changing demographic of PWH come new challenges for researchers and clinicians in how to identify, address, and manage the complex interplay of treated HIV infection and aging-associated factors. In response to these challenges, the annual International Workshop on HIV and Aging was initiated in 2009 as a multidisciplinary platform for scientific discourse on the research and clinical complications arising from the aging population of PWH. The multidisciplinary nature of the workshop has resulted in a wide range of topics addressed over the past 9 years, from basic mechanisms in aging and HIV pathogenesis, to epidemiology of aging within large cohorts, interventions, and implementation of clinical programs. Herein, we summarize the key topics discussed at the 9th Annual International Workshop on HIV and Aging 2018, including "inflammaging," mitochondrial dysfunction, exercise interventions, HIV-associated neurocognitive impairment, metabolic dysfunction, menopause, and polypharmacy. In addition to recent developments in research and clinical care, we discuss open questions and future research directions required to better understand the interaction of HIV and aging.

Single Cell Profiling Reveals PTEN Overexpression in Influenza-Specific B cells in Aging HIV-infected individuals on Anti-retroviral Therapy

Memory B cells (MBC) respond to secondary antigen challenge to protect against infection and to boost immunity following vaccinations. Despite effective treatment, chronic HIV infection disturbs MBCs by reducing numbers and altering functionality due to hyper-activation and increased apoptosis leading to suboptimal antibody responses against common infectious agents. We used single cell gene expression analysis to evaluate antigen-specific memory B cells in peripheral blood of virally-suppressed HIV-infected individuals and healthy controls stratified by serum H1N1 antibody response 3 weeks post-administration of the seasonal trivalent inactivated influenza vaccine. We used a fluorescent probe to isolate influenza H1N1-specific B cells and a multiplexed and targeted RT-PCR approach to measure expression levels of 96 genes involved in B cell activation and function. Gene profiling revealed a 4-gene predictive signature containing the phosphoinositide-3 kinase (PI3K) inhibitor, PTEN, for identifying antigen-specific MBC from HIV-infected individuals compared to healthy controls. Gene co-expression analysis showed that in addition to overexpression of PTEN, there was increased co-expression of type I interferon-associated genes with PTEN on single cell level in HIV compared to controls. This study highlights the persistent defects in MBC from HIV-infected individuals and points to the PI3K signaling pathway as a target for potential immune intervention.

Reduction in terminally differentiated T cells in virologically controlled HIV-infected aging patients on long-term antiretroviral therapy

Several studies have shown an increased accumulation of terminally differentiated T cells during HIV infection, suggestive of exhaustion/senescence, causing dysregulation of T cell homeostasis and function and rapid HIV disease progression. We have investigated whether long-term antiretroviral therapy (ART), which controls viremia and restores CD4 T cell counts, is correlated with reduction in terminally differentiated T cells, improved ratios of naïve to memory and function of T cells in 100 virologically controlled HIV-infected patients. We show that while the median frequencies of terminally differentiated CD4⁺ and CD8⁺ T cells (CD28^-, CD27^-, CD57⁺ and CD28^-CD57⁺), were higher in the virologically controlled HIV-infected patients’ cohort compared with uninfected individuals’ cohort, the frequencies of these cells significantly decreased with increasing CD4 T cell counts in HIV-infected patients. Although, the naïve CD4⁺ and CD8⁺ T cells were lower in HIV patients’ cohort than uninfected cohort, there was a significant increase in both naïve CD4⁺ and CD8⁺ T cells with increasing CD4 T cell counts in HIV-infected patients. The underlying mechanism behind this increased naïve CD4⁺ and CD8⁺ T cells in HIV-infected patients was due to an increase in recent thymic emigrants, CD4⁺CD31⁺, as compared to CD4⁺CD31^-. The CD4⁺ T cells of HIV-infected patients produced cytokines, including IL-2, IL-10 and IFN-γ comparable to uninfected individuals. In conclusion, virologically controlled HIV-infected patients on long-term ART show a significant reduction in terminally differentiated T cells, suggestive of decreased exhaustion/senescence, and improvement in the ratios of naïve to memory and function of T cells.