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1.
biorxiv; 2023.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2023.03.15.532728

ABSTRACT

The immune escape of Omicron-sublineage variants significantly subsides by the third dose of an mRNA vaccine. However, it is unclear how Omicron variant-neutralizing antibodies develop under repeated vaccination. We collected blood samples from 41 BNT162b2 vaccinees following the course of three injections and analyzed their B-cell receptor (BCR) repertoires at six time points in total. Five Omicron variant-neutralizing BCR heavy chain (HC) clonotypes were tracked chronologically in identical vaccinees before and after the third dose. Before the third injection, all five BCR HC clonotypes showed reactivity to the ancestral receptor-binding domain (RBD), and two BCR HC clonotypes developed similar reactivity to the Omicron RBD. The other three BCR HC clonotypes showed minimal or reduced reactivity to the Omicron RBD before the third dose, which induced further somatic hypermutation (SHM) and dramatically increased their affinity for the Omicron RBD. In the public IGHV3-53/3-66 and IGHJ6 clonotypes found in 19 vaccinees (46%), concomitant reactivity to the ancestral and Omicron RBDs resulted from SHMs such as Y58F and F27V and diversification of HCDR3 by SHM. Our findings suggest that SHM occurrence in the BCR space to broaden its specificity for unseen antigens is a counterprotective mechanism against the immune escape of virus variants.


Subject(s)
Heavy Chain Disease
2.
medrxiv; 2022.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2022.07.23.22277888

ABSTRACT

Background Coronavirus disease 2019 (COVID-19) pandemic affected millions of individuals and patients with cancer are known to be more susceptible. Vaccines against SARS-CoV-2 have been developed and used for patients with cancer, but scarce data is available on their efficacy in patients under active anti-cancer therapies. Materials and Methods In this study, we semi-quantitatively measured the titers of the immunoglobulin G against the anti-spike protein subunit 1 of SARS-CoV-2 after vaccination in early breast cancer patients with concurrent chemotherapy, endocrinal or targeted non-cytotoxic treatments, and no treatments. Results Standard doses of COVID-19 vaccines provided sufficient immune responses in patients with early breast cancer, regardless of the type of anticancer therapies. However, the post-vaccination serum anti-spike antibody titers were significantly lower in the patients under cytotoxic chemotherapy. Conclusion Our study emphasizes the importance of the personalized risk stratification and consideration for booster doses in more vulnerable populations.


Subject(s)
Endocrine System Diseases , Neoplasms , Breast Neoplasms , COVID-19
3.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.07.09.21260221

ABSTRACT

Genomic regions have been associated with COVID-19 susceptibility and outcomes, including the chr12q24.13 locus encoding antiviral proteins OAS1-3. Here, we report genetic, functional, and clinical insights into genetic associations within this locus. In Europeans, the risk of hospitalized vs. non-hospitalized COVID-19 was associated with a single 19Kb-haplotype comprised of 76 OAS1 variants included in a 95% credible set within a large genomic fragment introgressed from Neandertals. The risk haplotype was also associated with impaired spontaneous but not treatment-induced SARS-CoV-2 clearance in a clinical trial with pegIFN-{lambda}1. We demonstrate that two exonic variants, rs10774671 and rs1131454, affect splicing and nonsense-mediated decay of OAS1. We suggest that genetically-regulated loss of OAS1 expression contributes to impaired spontaneous clearance of SARS-CoV-2 and elevated risk of hospitalization for COVID-19. Our results provide the rationale for further clinical studies using interferons to compensate for impaired spontaneous SARS-CoV-2 clearance, particularly in carriers of the OAS1 risk haplotypes.


Subject(s)
COVID-19
4.
medrxiv; 2020.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2020.11.25.20233163

ABSTRACT

Acquired somatic mutations in hematopoietic stem and progenitor cells (clonal hematopoiesis or CH) are associated with advanced age, increased risk of cardiovascular and malignant diseases, and decreased overall survival. These adverse sequelae may be mediated by altered inflammatory profiles observed in patients with CH. A pro-inflammatory immunologic profile is also associated with worse outcomes of certain infections, including SARS-CoV-2 and its associated disease Covid-19. Whether CH predisposes to severe Covid-19 or other infections is unknown. Among 515 individuals with Covid-19 from Memorial Sloan Kettering (MSK) and the Korean Clonal Hematopoiesis (KoCH) consortia, we found that CH was associated with severe Covid-19 outcomes (OR=1.9, 95%=1.2-2.9, p=0.01). We further explored the relationship between CH and risk of other infections in 14,211 solid tumor patients at MSK. CH was significantly associated with risk of Clostridium Difficile (HR=2.0, 95% CI: 1.2-3.3, p=6x10-3) and Streptococcus/Enterococcus infections (HR=1.5, 95% CI=1.1-2.1, p=5x10-3). These findings suggest a relationship between CH and risk of severe infections that warrants further investigation.


Subject(s)
COVID-19 , Neoplasms , Infections
5.
biorxiv; 2020.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2020.06.26.174557

ABSTRACT

In six of seven severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients, VH clonotypes, encoded by either immunoglobin heavy variable (IGHV)3-53 or IGHV3-66 and immunoglobin heavy joining (IGHJ)6, were identified in IgG1, IgA1, and IgA2 subtypes, with minimal mutations, and could be paired with diverse light chains, resulting in binding to the SARS-CoV-2 receptor-binding domain (RBD). Because most human antibodies against the RBD neutralized the virus by inhibiting host cell entry, we selected one of these clonotypes and demonstrated that it could potently inhibit viral replication. Interestingly, these VH clonotypes pre-existed in six of 10 healthy individuals, predominantly as IgM isotypes, which could explain the expeditious and stereotypic development of these clonotypes among SARS-CoV-2 patients.One Sentence Summary Stereotypic-naïve SARS-CoV-2 neutralizing antibody clonotypes, encoded by IGHV3-53/IGHV3-66 and IGHJ6, were identified in most patients and pre-exist in the majority of the healthy population, predominantly as an IgM isotype.Competing Interest StatementThe authors have declared no competing interest.View Full Text


Subject(s)
COVID-19
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