Improve Vaccine Effectiveness Research Articles

A laponite-based immunologically active gel delivery system for long-acting tumor vaccine

Traditional bolus vaccines typically require multiple doses, which complicates the vaccination process and may cause missed shots, leading to sub-optimal immunity and reduced vaccine effectiveness. Herein, a gel-based long-acting vaccine system with self-adjuvant properties based on laponite was constructed to simplify vaccination procedures and improve vaccine effectiveness. Firstly, the gel system could recruit multiple types of immune cells to form immune niches. Secondly, it could achieve sustained delivery of antigens to lymph nodes by active transport and passive drainage. Then, the gel system triggered the formation of a large number of germinal centers, which elicited enhanced and durable humoral immune responses, as well as strong cellular immune responses. As a result, it eventually showed good prophylactic and therapeutic effects in a variety of tumor models including melanoma, colorectal cancer and peritoneal metastasis models. By further combining the immunoadjuvant CpG ODN and cytokine IL-12, the effect of the gel-vaccine could be further enhanced. In a murine peritoneal metastasis model of colorectal carcinoma, a single administration of the gel-vaccine resulted in complete tumor eradication in 8/9 mice. In summary, this study developed an immunologically active gel-vaccine system. And as a robust and versatile vaccine platform, by loading different antigens and adjuvants, this gel-vaccine system is expected to realize its better therapeutic potential.

Vaccination in Patients with Liver Cirrhosis: A Neglected Topic.

Patients with liver cirrhosis, due to their weakened innate and adaptive immunity, are more prone to frequent and severe vaccine-preventable infections. Moreover, impaired adaptive immunity results in a limited antibody response to vaccines. Despite this suboptimal antibody response, vaccines have proven to be very effective in reducing severe outcomes and deaths in these patients. In the Western world, regulatory authorities and scientific liver societies (e.g., AASLD and EASL) have recommended vaccinations for cirrhotic patients. However, despite these strong recommendations, vaccine coverage remains suboptimal. Improving vaccine effectiveness and safety information, providing comprehensive counseling to patients, fact-checking to combat fake news and disinformation and removing barriers to vaccination for disadvantaged individuals may help overcome the low coverage rate. In view of this, vaccines should be administered early in the course of chronic liver diseases, as their efficacy declines with the increasing severity of the disease.

A Comprehensive Review of Hepatitis B Vaccine Nonresponse and Associated Risk Factors.

Hepatitis B virus (HBV) infection remains a significant global health concern worldwide, contributing to high rates of mortality and morbidity, including chronic hepatitis B, cirrhosis, and hepatocellular carcinoma (HCC). Universal vaccination programs have significantly reduced the rate of HBV transmission; however, a subset of individuals fail to develop a protective immune response following vaccination and are termed nonresponders. A comprehensive search strategy using the PubMed, Google Scholar, and Web of Science databases was employed to search for relevant studies using keywords including "hepatitis B vaccine", "vaccine nonresponse", "immunogenicity", "immune response to the hepatitis B vaccine", and "associated risk factors". Factors influencing the vaccine's response include demographic factors, such as age and sex, with increased nonresponse rates being observed in older adults and males. Obesity, smoking, and alcohol consumption are lifestyle factors that decrease the vaccine response. Medical conditions, including diabetes, chronic kidney and liver diseases, HIV, celiac disease, and inflammatory bowel disease, affect the vaccine response. Major histocompatibility complex (MHC) haplotypes and genetic polymorphisms linked to immune regulation are genetic factors that further influence the vaccine's effectiveness. To reduce the global burden of hepatitis B infection, it is essential to understand these factors to improve vaccine effectiveness and develop individualized vaccination strategies.

Effectiveness of the varicella vaccine in the real world, a matched case-control study

BackgroundUniversal varicella vaccination has been introduced in many countries, but there are a number of important differences in their vaccination strategies. It is essential to establish a vaccination program that can maximize the benefits of varicella vaccine, but there is a lack of comprehensive research on the effectiveness of varicella vaccine in different vaccination status. MethodsUsing data from population-based surveillance platforms we conducted a 1:2 matched case-control study. The cases were clinically diagnosed varicella with onset from 2017 to 2021, 1–14 years old in Chaoyang District, Beijing. The controls were matched according to date of birth (±1 month), sex and residence. The vaccination data of the subjects were obtained from the Childhood Immunization Information Management System in Beijing. Using conditional logistic regression models with or without interaction terms, we evaluated the effectiveness of varicella vaccine in different vaccination status. ResultsA total of 2528 cases and 5056 controls were enrolled. This study found that whether the time since last vaccination was adjusted had a substantial effect on the comparing vaccine effectiveness (VE) between subgroups. After adjustment for the time since last vaccination, 1) the incremental VE of 2-dose was 49.6 % (95 % Confidence Interval [CI], 38.8–58.6) compared with 1-dose (93.9 % vs. 88.0 %); 2) Among children who received one dose, the risk of chickenpox in children vaccinated at 18–23 months was 1.382 (95 %CI, 1.084–1.762) times that in children vaccinated at 12–17 months. 3) the VE with less than one, two, and three year intervals is higher than that with six-year-intervals (P < 0.05), respectively. ConclusionsWhen comparing VE between subgroups of different vaccination status, the time since last vaccination should be adjusted. The first dose of varicella vaccine should be given as early as the second year of life, and the second dose can improve vaccine effectiveness.

Dendritic cell targeting peptide plus Salmonella FliCd flagellin fused outer membrane protein H (OmpH) demonstrated increased efficacy against infections caused by different Pasteurella multocida serogroups in mouse models

As the major outer membrane protein (OMP) presents in the Pasteurella multocida envelope, OmpH was frequently expressed for laboratory assessments of its immunogenicity against P. multocida infections, but the results are not good. In this study, we modified OmpH with dendritic cell targeting peptide (Depeps) and/or Salmonella FliCd flagellin, and expressed three types of recombinant proteins with the MBP tag (rDepeps-FliC-OmpH-MBP, rDepeps-OmpH-MBP, rFliC-OmpH-MBP). Assessments in mouse models revealed that vaccination with rDepeps-FliC-OmpH-MBP, rDepeps-OmpH-MBP, or rFliC-OmpH-MBP induced significant higher level of antibodies as well as IFN-γ and IL-4 in murine sera than vaccination with rOmpH-MBP (P < 0.5). Vaccination with the three modified proteins also provided increased protection (rDepeps-FliC-OmpH-MBP, 70 %; rDepeps-OmpH-MBP, 50 %; rFliC-OmpH-MBP, 60 %) against P. multocida serotype D compared to vaccination with rOmpH-MBP (30 %). In mice vaccinated with different types of modified OmpHs, a significantly decreased bacterial strains were recovered from bloods, lungs, and spleens compared to rOmpH-MBP-vaccinated mice (P < 0.5). Notably, our assessments also demonstrated that vaccination with rDepeps-FliC-OmpH-MBP provided good protection against infections caused by a heterogeneous group of P. multocida serotypes (A, B, D). Our above findings indicate that modification with DCpep and Salmonella flagellin could be used as a promising strategy to improve vaccine effectiveness.

Influenza burden averted with a cell-based quadrivalent seasonal influenza vaccine compared with egg-based quadrivalent seasonal influenza vaccine

ABSTRACT Background Cell-based quadrivalent inactivated influenza vaccines (IIV4c) avoid egg-adaptive mutations found in egg-based production, improving vaccine effectiveness (VE). Studies demonstrate improved VE for IIV4c relative to egg-based quadrivalent inactivated influenza vaccines (IIV4). Research Design and Methods We built on a static compartmental model developed by the CDC to estimate the influenza burden in persons 0–64 years that would be additionally averted by vaccination with IIV4c vs. IIV4. Model inputs were based on published data from 2017–2018, 2018–2019, and 2019–2020 Northern Hemisphere influenza seasons for the US. Results Over 3 influenza seasons, relative to IIV4, IIV4c would avert 31–39% more symptomatic cases, 29–40% more outpatient visits, 29–38% more hospitalizations and ICU admissions, and 34–49% more deaths vs. IIV4. In a deterministic sensitivity analysis, the main drivers were the relative VE of IIV4c vs. IIV4 in the 2017–2018 season and influenza burden estimates for the 2018–2019 and 2019–2020 seasons. Probabilistic sensitivity analysis showed that the interquartile range of symptomatic cases was ± 13% of baseline in 2017–2018, ±8% in 2018–2019, and ± 7% in 2019–2020. Conclusions IIV4c prevented significantly more symptomatic cases, outpatient visits, hospitalizations, and deaths than IIV4 in persons aged 0–64 years over 3 influenza seasons.

Impact of Immunomodulatory Therapy on COVID-19 Vaccine Response in Patients with Autoimmune Inflammatory Rheumatic Diseases.

Coronavirus disease 2019 (COVID-19) vaccination is essential for patients with autoimmune inflammatory rheumatic diseases (AIIRD) to reduce the risk of morbidity and mortality associated with serious COVID-19 infection. With endemicity, waning of vaccine- and infection-acquired immunity, and development of SARS-CoV-2 variants, the need for additional doses of vaccines against serious illness in high-risk immunocompromised persons remains imperative. This review examines how immunomodulatory therapies affect vaccine-induced immune response in patients with AIIRD. Glucocorticoids, methotrexate, azathioprine, calcineurin inhibitors, mycophenolate mofetil, tumor necrosis factor inhibitors, and abatacept have been shown to variably attenuate both humoral and cellular immune responses to vaccination. Janus kinase inhibitors reduce humoral immune response. In contrast, sulfasalazine, leflunomide, belimumab, interleukin (IL)-17, IL-12/23, IL-6, and IL-1 inhibitors appear favorable, with mild or no impact on vaccine response. Although rituximab is known to profoundly diminish humoral immune response, cellular immunity is relatively preserved. Administering a third and subsequent vaccine dose or temporally coordinating the dosing of immunomodulatory drugs may improve vaccine effectiveness. Further research is needed to personalise vaccination strategies for AIIRD patients, considering their specific immunomodulatory treatments.

Intranasal delivery of LaAg vaccine improves immunity of aged mice against visceral Leishmaniasis

There are no approved vaccines yet for human visceral leishmaniasis (VL), the most severe form of the leishmaniasis clinical manifestations that is fatal in over 95 % of untreated cases. It is well-accepted that immunological changes during aging have deleterious impact on the efficacy of vaccines and response to infections. In this work, we compared the response of young and aged mice to intranasal vaccination with killed Leishmania amazonensis promastigote antigens (LaAg) that were then challenged with L. infantum infection, a species that causes visceral leishmaniasis. Intranasal vaccination with LaAg induced a similar reduction in parasitism and hepatosplenomegaly in both young and aged mice compared to their unvaccinated counterparts. Following infection, there was also a less prominent inflammatory profile particularly in the vaccinated aged group, with lower production of TNF-α and nitrite compared to the respective unvaccinated group. Interestingly, the LaAg intranasal vaccination promoted increased production of IFN-γ that was observed in both young- and aged vaccinated groups. Additionally, CD4+ and CD8+T cells from both vaccinated groups presented decreased expression of the inhibitory receptors PD-1 and KLRG1 compared to their unvaccinated controls. Interestingly, a strong positive correlation was observed between the expression of both inhibitory receptors PD-1 and KLRG1 and parasitism, which was more conspicuous in the unvaccinated-aged mice than in the others. Overall, this study helps define new strategies to improve vaccine effectiveness and provides a perspective for prophylactic alternatives against leishmaniasis.

Redirecting antibody responses from egg-adapted epitopes following repeat vaccination with recombinant or cell culture-based versus egg-based influenza vaccines

Repeat vaccination with egg-based influenza vaccines could preferentially boost antibodies targeting the egg-adapted epitopes and reduce immunogenicity to circulating viruses. In this randomized trial (Clinicaltrials.gov: NCT03722589), sera pre- and post-vaccination with quadrivalent inactivated egg-based (IIV4), cell culture-based (ccIIV4), and recombinant (RIV4) influenza vaccines were collected from healthcare personnel (18-64 years) in 2018−19 (N = 723) and 2019−20 (N = 684) influenza seasons. We performed an exploratory analysis. Vaccine egg-adapted changes had the most impact on A(H3N2) immunogenicity. In year 1, RIV4 induced higher neutralizing and total HA head binding antibodies to cell- A(H3N2) virus than ccIIV4 and IIV4. In year 2, among the 7 repeat vaccination arms (IIV4-IIV4, IIV4-ccIIV4, IIV4-RIV4, RIV4-ccIIV4, RIV4-RIV4, ccIIV4-ccIIV4 and ccIIV4-RIV4), repeat vaccination with either RIV4 or ccIIV4 further improved antibody responses to circulating viruses with decreased neutralizing antibody egg/cell ratio. RIV4 also had higher post-vaccination A(H1N1)pdm09 and A(H3N2) HA stalk antibodies in year 1, but there was no significant difference in HA stalk antibody fold rise among vaccine groups in either year 1 or year 2. Multiple seasons of non-egg-based vaccination may be needed to redirect antibody responses from immune memory to egg-adapted epitopes and re-focus the immune responses towards epitopes on the circulating viruses to improve vaccine effectiveness.

Cost-effectiveness analysis of cell-based versus egg-based quadrivalent influenza vaccines in the pediatric population in Taiwan.

Cell-based influenza vaccines avoid egg-adaptive mutations, potentially improving vaccine effectiveness. We assessed the one-season cost-effectiveness of cell-based quadrivalent influenza vaccine (QIVc) against that of egg-derived quadrivalent influenza vaccines (QIVe) in children (6 months to 17 years of age) from payer and societal perspectives in Taiwan using an age-stratified static model. Base case and high egg adaptation scenarios were assessed. Deterministic and probabilistic sensitivity analyses were performed. The incremental cost-effectiveness ratio (ICER) threshold in Taiwan was assumed to be USD 99 177/quality-adjusted life year (QALY). Compared to QIVe, QIVc would prevent 15 665 influenza cases, 2244 complicated cases, and 259 hospitalizations per year. The base case ICER was USD 68 298/QALY and USD 40 085/QALY from the payer and societal perspective, respectively. In the high egg adaptation scenario, the ICER was USD 45 782/QALY from the payer's perspective and USD 17 489/QALY from the societal perspective. Deterministic sensitivity analyses indicated that infection incidence rate, vaccination coverage, and prevalence of the A/H3N2 strain were the main drivers of ICER. In conclusion, switching the immunization strategy from QIVe to QIVc is predicted to reduce the influenza-associated disease burden and be cost-effective for the pediatric population in Taiwan. The potential benefits of QIVc would be even higher during influenza seasons with high levels of egg adaptation.

Exploring structural engineering approach to formulate and characterize next-generation adjuvants.

It is critical to emphasize the importance of vaccination as it protects us against harmful pathogens. Despite significant progress in vaccine development, there is an ongoing need to develop vaccines that are not only safe but also highly effective in protecting against severe infections. Subunit vaccines are generally safe, but they frequently fail to elicit strong immune responses. As a result, there is a need to improve vaccine effectiveness by combining them with adjuvants, which have the potential to boost the immune system many folds. The process of developing these adjuvants requires searching for molecules capable of activating the immune system, combining these promising compounds with an antigen, and then testing this combination using animal models before approving it for clinical use. Liposomal adjuvants work as delivery adjuvants and its activity depends on certain parameters such as surface charge, vesicle size, surface modification and route of administration. Self-assembly property of peptide adjuvants and discovery of hybrid peptides have widened the scope of peptides in vaccine formulations. Since most pathogenic molecules are not peptide based, phage display technique allows for screening peptide mimics for such pathogens that have potential as adjuvants. This chapter discusses about peptide and liposome-based adjuvants focusing on their properties imparting adjuvanticity along with the methods of formulating them. Methods of adjuvant characterization important for an adjuvant to be approved for clinical trials are also discussed. These include assays for cytotoxicity, T-lymphocyte proliferation, dendritic cell maturation, cytokine and antibody production, toll-like receptor dependent signaling and adjuvant half-life.

TLR agonists as vaccine adjuvants in the prevention of viral infections: an overview.

Tol-like receptor (TLR) agonists, as potent adjuvants, have gained attention in vaccine research for their ability to enhance immune responses. This study focuses on their application in improving vaccine efficacy against key viral infections, including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), SARS-CoV-2, influenza virus, and flaviviruses, including West Nile virus, dengue virus, and chikungunya virus. Vaccines are crucial in preventing microbial infections, including viruses, and adjuvants play a vital role in modulating immune responses. However, there are still many diseases for which effective vaccines are lacking or have limited immune response, posing significant threats to human health. The use of TLR agonists as adjuvants in viral vaccine formulations holds promise in improving vaccine effectiveness. By tailoring adjuvants to specific pathogens, such as HBV, HCV, HIV, SARS-CoV-2, influenza virus, and flavivirus, protective immunity against chronic and emerging infectious disease can be elicited.

Antibody-Mediated Suppression Regulates the Humoral Immune Response to Influenza Vaccination in Humans.

Preexisting immunity, including memory B cells and preexisting antibodies, can modulate antibody responses to influenza in vivo to antigenically related antigens. We investigated whether preexisting hemagglutination inhibition (HAI) antibodies targeting the K163 epitope on the hemagglutinin (K163 antibodies) could affect antibody responses following vaccination with A/California/07/2009-like A(H1N1)pdm09 influenza viruses in humans. Pre- and postvaccination sera collected from 300 adults (birth years, 1961-1998) in 6 seasons (2010-2016) were analyzed by HAI assays with 2 reverse genetics viruses and A(H1N1) viruses circulated from 1977 to 2018. Antibody adsorption assays were used to verify the preexisting K163 antibody-mediated suppression effect. Preexisting K163 antibody titers ≥80 affected HAI antibody responses following influenza vaccination containing A/California/07/2009-like antigens. At high K163 antibody concentrations (HAI antibody titers ≥160), all HAI antibody responses were suppressed. However, at moderate K163 antibody concentrations (HAI antibody titer, 80), only K163 epitope-specific antibody responses were suppressed, and novel HAI antibody responses targeting the non-K163 epitopes were induced by vaccination. Novel antibodies targeting non-K163 epitopes cross-reacted with newly emerging A(H1N1)pdm09 strains with a K163Q mutation rather than historic 1977-2007 A(H1N1) viruses. K163 antibody-mediated suppression shapes antibody responses to A(H1N1)pdm09 vaccination. Understanding how preexisting antibodies suppress and redirect vaccine-induced antibody responses is of great importance to improve vaccine effectiveness.

Dynamics Analysis of an 11-Dimensional Multiscale COVID-19 Model with Interval Parameters

This paper investigates an 11-dimensional slow–fast system of multiscale COVID-19 model with interval parameters. For the slow subsystem, the local dynamics of disease-free equilibrium (DFE) and endemic equilibrium (EE) are studied by using the fast–slow theory. Two criteria of the existence of forward and backward bifurcations are further obtained. When the basic reproduction number [Formula: see text] is less than unity, we show that bistabilities of DFE and EE for [Formula: see text] can be caused by backward bifurcation. Thus, controlling [Formula: see text] below critical value [Formula: see text] is effective to eliminate endemic diseases. Meanwhile, the slow subsystem undergoes saddle-node bifurcation at [Formula: see text] and undergoes pitchfork bifurcation at [Formula: see text] for EE. Moreover, the stability and bifurcation of the multiscale full system are established. As an application, the numerical simulations of real data of COVID-19 in Hong Kong are used to verify these results, which show that increasing vaccination rate, improving vaccine effectiveness and decreasing the fraction of individuals in risky state 2 are necessary to control the COVID-19.

Alpha-galactosylceramide as adjuvant induces protective cell-mediated immunity against Leishmania mexicana infection in vaccinated BALB/c mice.

Adjuvants represent a promising strategy to improve vaccine effectiveness against infectious diseases such as leishmaniasis. Vaccination with the invariant natural killer T cell ligand α-galactosylceramide (αGalCer) has been used successfully as adjuvant, generating a Th1-biased immunomodulation. This glycolipid enhances experimental vaccination platforms against intracellular parasites including Plasmodium yoelii and Mycobacterium tuberculosis. In the present study, we assessed the protective immunity induced by a single-dose intraperitoneal injection of αGalCer (2μg) co-administrated with a lysate antigen of amastigotes (100μg) against Leishmania mexicana infection in BALB/c mice. The prophylactic vaccination led to 5.0-fold reduction of parasite load at the infection site, compared to non-vaccinated mice. A predominant pro-inflammatory response was observed in challenged vaccinated mice, represented by a 1.9 and 2.8-fold-increase of IL-1β and IFN-γ producing cells, respectively, in the lesions, and by 23.7-fold-increase of IFN-γ production in supernatants of restimulated splenocytes, all compared to control groups. The co-administration of αGalCer also stimulated the maturation of splenic dendritic cells and modulated a Th1-skewed immune response, with high amounts of IFN-γ production in serum. Furthermore, peritoneal cells of αGalCer-immunized mice exhibited an elevated expression of Ly6G and MHCII. These findings indicate that αGalCer improves protection against cutaneous leishmaniasis, supporting evidence for its potential use as adjuvant in Leishmania-vaccines.

Modeling the potential health impacts of delayed strain selection on influenza hospitalization and mortality with mRNA vaccines

BackgroundInfluenza viruses are constantly evolving through antigenic drift, which makes vaccines potentially ill-matched to circulating strains due to the time between strain selection and distribution. mRNA technology could improve vaccine effectiveness (VE) by reducing this time. Significant private and public investments would be required to accommodate accelerated vaccine development and approval. Hence, it is important to understand the potential impact of mRNA technology on influenza hospitalizations and mortality. MethodsWe developed an age-stratified dynamic model of influenza transmission to evaluate the potential impact of increased VE (increased protection against either infection or only hospitalization) on hospitalizations and mortality in the United States. We assume that mRNA technology allows for delaying the time to strain choice, which might increase efficacy, but it does not reduce the time needed for distribution and administration, which might reduce availability. To assess this tradeoff, we evaluated two scenarios where strain choice was delayed until late summer resulting in a more effective vaccine available to (1) all age groups by October, or (2) adults 65 years and older starting in August. ResultsIf not available until October, the vaccine would need a minimum of 95% effectiveness against infection to see a decrease in hospitalizations and deaths in all age groups. When delayed until November, even a 100% effective vaccine had no significant impact. For the elderly, the minimum required VE (against infection) was 50% to reduce hospitalizations and deaths. Moreover, a vaccine with 80% VE against infection available in August for the 65 + age group was better than a 95% effective vaccine available in October for all ages. ConclusionsAs the majority of influenza-associated hospitalizations and deaths are in adults 65 years and older, a combination policy targeting higher VE and coverage for this age group in the short term would be the most efficacious.

SARS-CoV-2 Antibody Responses to the Ancestral SARS-CoV-2 Strain and Omicron BA.1 and BA.4/BA.5 Variants in Nursing Home Residents After Receipt of Bivalent COVID-19 Vaccine — Ohio and Rhode Island, September–November 2022

Introduction of monovalent COVID-19 mRNA vaccines in late 2020 helped to mitigate disproportionate COVID-19-related morbidity and mortality in U.S. nursing homes (1); however, reduced effectiveness of monovalent vaccines during the period of Omicron variant predominance led to recommendations for booster doses with bivalent COVID-19 mRNA vaccines that include an Omicron BA.4/BA.5 spike protein component to broaden immune response and improve vaccine effectiveness against circulating Omicron variants (2). Recent studies suggest that bivalent booster doses provide substantial additional protection against SARS-CoV-2 infection and severe COVID-19-associated disease among immunocompetent adults who previously received only monovalent vaccines (3).* The immunologic response after receipt of bivalent boosters among nursing home residents, who often mount poor immunologic responses to vaccines, remains unknown. Serial testing of anti-spike protein antibody binding and neutralizing antibody titers in serum collected from 233 long-stay nursing home residents from the time of their primary vaccination series and including any subsequent booster doses, including the bivalent vaccine, was performed. The bivalent COVID-19 mRNA vaccine substantially increased anti-spike and neutralizing antibody titers against Omicron sublineages, including BA.1 and BA.4/BA.5, irrespective of previous SARS-CoV-2 infection or previous receipt of 1 or 2 booster doses. These data, in combination with evidence of low uptake of bivalent booster vaccination among residents and staff members in nursing homes (4), support the recommendation that nursing home residents and staff members receive a bivalent COVID-19 booster dose to reduce associated morbidity and mortality (2).

HPV genotyping in biopsies of HSIL and invasive cervical cancers in women living with HIV: A cohort- and a nested -case control study

ObjectiveTo characterize HPV genotype distribution in HSIL and ICC- biopsies, of WLWH, in Europe, as compared to HIV-negative women. DesignCohort- and nested -case control study. MethodWe characterized HPV genotype distribution by performing PCR on HSIL and ICC biopsies from WLWH (n = 170); 85 cases were compared to 85 HIV-negative matched controls. The proportion of patients that might be protected by HPV vaccines was estimated. ResultsAmong WLWH (median age 36 years-old, median duration of HIV infection 70,5 months, 79% under cART): the most frequently detected HPV were HPV16 (30%), HPV35 (16%), HPV58 (14,7%), HPV31 (13,5%), and HPV52 (11,7%). HPV16 was less frequently found in WLWH, originating from Central Africa (20,5%) compared to other African regions (35,5%) (p = 0,05) or world regions (38,8%) (p = 0,007). Multiple versus single high-risk HPV infections were associated with younger age (≤35 years)(odds ratio (OR) 2,65 (95%IC: 1,3–5,2,p = 0,002), lymphocyte CD4 count < 350 cells / µL (OR 2,7 (95%IC: 2–8,5; p = 0,005), use of cART for < 18 month OR 2,2 (95%IC: 1,1–4,5),p = 0,04) or a cumulative time with undetectable HIV viral load of less than 12 months (OR 4,2 (95%IC: 2–8.5,p = 0,001). HPV 31, 33 and 35 were more frequently detected in samples from WLWH than in HIV-negative controls (p < 0,05). The 9-valent vaccine would increase HPV protection, in HIV-positive and negative women (p < 0,001). ConclusionWLWH are more frequently infected with high-risk HPV other than 16 and 18 than HIV-negative ones. The use of 9-valent vaccine may prevent HSIL or ICC in up to 85% of the women. Adding HPV 35 to the HPV vaccine panel, might improve vaccine effectiveness in WLWH.

Association between regular physical activity and the protective effect of vaccination against SARS-CoV-2 in a South African case–control study

BackgroundBoth vaccination and physical activity have been shown to independently decrease the likelihood of severe COVID-19 infection.ObjectiveTo assess the association between regular physical activity and vaccination against COVID-19 among healthcare...

Characteristics and Roles of T Follicular Helper Cells in SARS-CoV-2 Vaccine Response.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is critical to controlling the coronavirus disease 2019 (COVID-19) pandemic. However, a weak response to the vaccine and insufficient persistence of specific antibodies may threaten the global impact of mass vaccination campaigns. This study summarizes the internal factors of the body that affect the effectiveness of the SARS-CoV-2 vaccine. T follicular helper (Tfh) cells support germinal center B cells to produce vaccine-specific immunoglobulins. A reduction in the Tfh cell number and a shift in the subset phenotypes caused by multiple factors may impair the production and persistence of high-affinity antibodies. Besides efficacy differences caused by the different types of vaccines, the factors that affect vaccine effectiveness by intervening in the Tfh cell response also include age-related defects, the polarity of the body microenvironment, repeated immunization, immunodeficiency, and immunosuppressive treatments. Assessing the phenotypic distribution and activation levels of Tfh cell subsets after vaccination is helpful in predicting vaccine responses and may identify potential targets for improving vaccine effectiveness.