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Nature Immunology Jun 2024
PubMed: 38877179
DOI: 10.1038/s41590-024-01891-0 -
Frontiers in Immunology 2024The VH6-1 class of antibodies includes some of the broadest and most potent antibodies that neutralize influenza A virus. Here, we elicit and isolate anti-idiotype...
The VH6-1 class of antibodies includes some of the broadest and most potent antibodies that neutralize influenza A virus. Here, we elicit and isolate anti-idiotype antibodies against germline versions of VH6-1 antibodies, use these to sort human leukocytes, and isolate a new VH6-1-class member, antibody L5A7, which potently neutralized diverse group 1 and group 2 influenza A strains. While its heavy chain derived from the canonical IGHV6-1 heavy chain gene used by the class, L5A7 utilized a light chain gene, IGKV1-9, which had not been previously observed in other VH6-1-class antibodies. The cryo-EM structure of L5A7 in complex with Indonesia 2005 hemagglutinin revealed a nearly identical binding mode to other VH6-1-class members. The structure of L5A7 bound to the isolating anti-idiotype antibody, 28H6E11, revealed a shared surface for binding anti-idiotype and hemagglutinin that included two critical L5A7 regions: an FG motif in the third heavy chain-complementary determining region (CDR H3) and the CDR L1 loop. Surprisingly, the chemistries of L5A7 interactions with hemagglutinin and with anti-idiotype were substantially different. Overall, we demonstrate anti-idiotype-based isolation of a broad and potent influenza A virus-neutralizing antibody, revealing that anti-idiotypic selection of antibodies can involve features other than chemical mimicry of the target antigen.
Topics: Humans; Influenza A virus; Antibodies, Viral; Antibodies, Neutralizing; Antibodies, Anti-Idiotypic; Hemagglutinin Glycoproteins, Influenza Virus; Influenza, Human; Animals; Immunoglobulin Heavy Chains
PubMed: 38873606
DOI: 10.3389/fimmu.2024.1399960 -
Life Sciences Jun 2024
PubMed: 38866604
DOI: 10.1016/j.lfs.2024.122831 -
BMC Public Health Jun 2024As of 2024, vaccination remains the main mitigation measure against COVID-19, but there are contradictory results on whether people living with HIV (PLWH) are less...
BACKGROUND
As of 2024, vaccination remains the main mitigation measure against COVID-19, but there are contradictory results on whether people living with HIV (PLWH) are less protected by vaccines than people living without HIV (PLWoH). In this study we compared the risk of SARS-CoV-2 infection and COVID-19 hospitalisation following full vaccination in PLWH and PLWoH.
METHODS
We linked data from the vaccination registry, the COVID-19 surveillance system and from healthcare/pharmacological registries in four Italian regions. We identified PLWH fully vaccinated (14 days post completion of the primary cycle) and matched them at a ratio of 1:4 with PLWoH by week of vaccine administration, age, sex, region of residence and comorbidities. Follow-up started on January 24, 2021, and lasted for a maximum of 234 days. We used the Kaplan-Meier estimator to calculate the cumulative incidence of infection and COVID-19 hospitalisation in both groups, and we compared risks using risk differences and ratios taking PLWoH as the reference group.
RESULTS
We matched 42,771 PLWH with 171,084 PLWoH. The overall risk of breakthrough infection was similar in both groups with a rate ratio (RR) of 1.10 (95% confidence interval (CI):0.80-1.53). The absolute difference between groups at the end of the study period was 8.28 events per 10,000 person-days in the PLWH group (95%CI:-18.43-40.29). There was a non-significant increase the risk of COVID-19 hospitalisation among PLWH (RR:1.90; 95%CI:0.93-3.32) which corresponds to 6.73 hospitalisations per 10,000 individuals (95%CI: -0.57 to 14.87 per 10,000).
CONCLUSIONS
Our findings suggest PLWH were not at increased risk of breakthrough SARS-CoV-2 infection or COVID-19 hospitalisation following a primary cycle of mRNA vaccination.
Topics: Humans; Hospitalization; Italy; COVID-19; Male; Female; Middle Aged; HIV Infections; Adult; COVID-19 Vaccines; Aged; SARS-CoV-2; Registries; Young Adult; Risk Factors; Vaccination; Incidence; Breakthrough Infections
PubMed: 38862939
DOI: 10.1186/s12889-024-19071-y -
Scientific Reports Jun 2024African Green (Vervet) monkeys have been extensively studied to understand the pathogenesis of infectious diseases. Using vervet monkeys as pre-clinical models may be an...
African Green (Vervet) monkeys have been extensively studied to understand the pathogenesis of infectious diseases. Using vervet monkeys as pre-clinical models may be an attractive option for low-resourced areas as they are found abundantly and their maintenance is more cost-effective than bigger primates such as rhesus macaques. We assessed the feasibility of using vervet monkeys as animal models to examine the immunogenicity of HIV envelope trimer immunogens in pre-clinical testing. Three groups of vervet monkeys were subcutaneously immunized with either the BG505 SOSIP.664 trimer, a novel subtype C SOSIP.664 trimer, CAP255, or a combination of BG505, CAP255 and CAP256.SU SOSIP.664 trimers. All groups of vervet monkeys developed robust binding antibodies by the second immunization with the peak antibody response occurring after the third immunization. Similar to binding, antibody dependent cellular phagocytosis was also observed in all the monkeys. While all animals developed potent, heterologous Tier 1 neutralizing antibody responses, autologous neutralization was limited with only half of the animals in each group developing responses to their vaccine-matched pseudovirus. These data suggest that the vervet monkey model may yield distinct antibody responses compared to other models. Further study is required to further determine the utility of this model in HIV immunization studies.
Topics: Animals; HIV Antibodies; Chlorocebus aethiops; Antibodies, Neutralizing; AIDS Vaccines; HIV-1; Antibody Formation; HIV Infections; env Gene Products, Human Immunodeficiency Virus; Disease Models, Animal; Immunization
PubMed: 38858452
DOI: 10.1038/s41598-024-63703-7 -
The Lancet. HIV Jul 2024
Topics: Humans; HIV Infections; British Columbia; Male; Female
PubMed: 38848737
DOI: 10.1016/S2352-3018(24)00117-6 -
Cell Reports Jun 2024The development of vaccines and therapeutics that are broadly effective against known and emergent coronaviruses is an urgent priority. We screened the circulating B...
The development of vaccines and therapeutics that are broadly effective against known and emergent coronaviruses is an urgent priority. We screened the circulating B cell repertoires of COVID-19 survivors and vaccinees to isolate over 9,000 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific monoclonal antibodies (mAbs), providing an expansive view of the SARS-CoV-2-specific Ab repertoire. Among the recovered antibodies was TXG-0078, an N-terminal domain (NTD)-specific neutralizing mAb that recognizes diverse alpha- and beta-coronaviruses. TXG-0078 achieves its exceptional binding breadth while utilizing the same VH1-24 variable gene signature and heavy-chain-dominant binding pattern seen in other NTD-supersite-specific neutralizing Abs with much narrower specificity. We also report CC24.2, a pan-sarbecovirus neutralizing antibody that targets a unique receptor-binding domain (RBD) epitope and shows similar neutralization potency against all tested SARS-CoV-2 variants, including BQ.1.1 and XBB.1.5. A cocktail of TXG-0078 and CC24.2 shows protection in vivo, suggesting their potential use in variant-resistant therapeutic Ab cocktails and as templates for pan-coronavirus vaccine design.
PubMed: 38848216
DOI: 10.1016/j.celrep.2024.114307 -
Vaccine Jun 2024Priming with two doses of AZD1222 (Oxford-AstraZeneca; ChAd) followed by a third mRNA vaccine boosting is considered in several countries, yet comparisons between...
BACKGROUND
Priming with two doses of AZD1222 (Oxford-AstraZeneca; ChAd) followed by a third mRNA vaccine boosting is considered in several countries, yet comparisons between heterologous and homologous booster efficacy remain unexplored.
AIM
To evaluate and contrast the immunogenicity of homologous and heterologous boosting regimens.
METHOD
The study examined antibody responses in 1113 subjects, comprising 895 vaccine-naïve individuals across different vaccination strategies (partial, primary series, heterologous booster, homologous booster) and 218 unvaccinated, naturally infected individuals. Assessments included neutralizing total antibodies (NTAbs), total antibodies (TAbs), anti-S-RBD IgG, and anti-S1 IgA levels.
RESULTS
The study found mRNA vaccines to exhibit superior immunogenicity in primary series vaccination compared to ChAd, with mRNA-1273 significantly enhancing NTAbs, TAbs, anti-S-RBD IgG, and anti-S1 IgA levels (p < 0.001). Both booster types improved antibody levels beyond primary outcomes, with no significant difference in TAbs and anti-S-RBD IgG levels between regimens. However, homologous mRNA boosters significantly outperformed heterologous boosters in enhancing NTAbs and anti-S1 IgA levels, with the BNT/BNT/BNT regimen yielding particularly higher enhancements (p < 0.05).
CONCLUSION
The study concludes that although TAbs and anti-S-RBD IgG antibody levels are similar for both regimens, homologous mRNA boosting outperform heterologous regimen by enhancing anti-S1 IgA and neutralizing antibody levels.
PubMed: 38845303
DOI: 10.1016/j.vaccine.2024.06.010 -
Nature Communications Jun 2024Kaposi sarcoma associated herpesvirus (KSHV) is associated with around 1% of all human tumors, including the B cell malignancy primary effusion lymphoma (PEL), in which...
Kaposi sarcoma associated herpesvirus (KSHV) is associated with around 1% of all human tumors, including the B cell malignancy primary effusion lymphoma (PEL), in which co-infection with the Epstein Barr virus (EBV) can almost always be found in malignant cells. Here, we demonstrate that KSHV/EBV co-infection of mice with reconstituted human immune systems (humanized mice) leads to IgM responses against both latent and lytic KSHV antigens, and expansion of central and effector memory CD4 and CD8 T cells. Among these, KSHV/EBV dual-infection allows for the priming of CD8 T cells that are specific for the lytic KSHV antigen K6 and able to kill KSHV/EBV infected B cells. This suggests that K6 may represent a vaccine antigen for the control of KSHV and its associated pathologies in high seroprevalence regions, such as Sub-Saharan Africa.
Topics: Animals; Herpesvirus 8, Human; Humans; B-Lymphocytes; Mice; CD8-Positive T-Lymphocytes; Epstein-Barr Virus Infections; Coinfection; CD4-Positive T-Lymphocytes; Herpesvirus 4, Human; Herpesviridae Infections; Immunoglobulin M; Antigens, Viral; Mice, SCID; Lymphoma, Primary Effusion; Antibodies, Viral
PubMed: 38844783
DOI: 10.1038/s41467-024-49209-w -
Journal of Controlled Release :... Jun 2024Influenza outbreaks are a major burden worldwide annually. While seasonal vaccines do provide protection against infection, they are limited in that they need to be...
Influenza outbreaks are a major burden worldwide annually. While seasonal vaccines do provide protection against infection, they are limited in that they need to be updated every year to account for the constantly mutating virus. Recently, lipid nanoparticles (LNPs) encapsulating mRNA have seen major success as a vaccine platform for SARS-CoV-2. Herein, we applied LNPs to deliver an mRNA encoding a computationally optimized broadly active (COBRA) influenza immunogen. These COBRA mRNA LNPs induced a broadly active neutralizing antibody response and protection after lethal influenza challenge. To further increase the immunogenicity of the COBRA mRNA LNPs, we combined them with acetalated dextran microparticles encapsulating a STING agonist. Contrary to recent findings, the STING agonist decreased the immunogenicity of the COBRA mRNA LNPs which was likely due to a decrease in mRNA translation as shown in vitro. Overall, this work aids in future selection of adjuvants to use with mRNA LNP vaccines.
PubMed: 38844178
DOI: 10.1016/j.jconrel.2024.06.007