Seroconversion rates following COVID-19 vaccination among patients with cancer.

https://cdr.lib.unc.edu/downloads/vx021q731

SARS-CoV-2 mRNA vaccine induces robust specific and cross-reactive IgG and unequal neutralizing antibodies in naive and previously infected people

Immunogenicity of a heterologous COVID-19 vaccine after failed vaccination in a lymphoma patient.

It is well established that COVID-19 carries a higher risk of morbidity and mortality in patients with hematologic malignancies, however, very little data on ethnicity specific responses in this particular patient population currently exist. We established a program of rapid vaccination and evaluation of antibody-mediated response to all EUA COVID-19 vaccines in an inner city minority population to determine the factors that contribute to the poor seroconversion to COVID-19 vaccination in this population. We conducted a cross-sectional cohort study of 126 patients with hematologic malignancies in the outpatient practices of our institution who completed their vaccination series with one of the three FDA EUA COVID-19 vaccines, Moderna, Pfizer, or Johnson & Johnson (J&J). We qualitatively measured Spike IgG production in all patients using the AdviseDx SARS-CoV-2 IgG II assay and quantitatively in 106 patients who completed their vaccination series with at least 14 days after the 2nd dose of the Moderna or Pfizer vaccines or 28d after the single J&J vaccine. Patient characteristics were analyzed using standard descriptive statistics and associations between patient characteristics, cancer subtypes, treatments, and vaccine response were assessed using Fisher Exact test or Kruskal-Wallis Rank Sum test. The majority of patients (74%) were minorities. Seventy patients (60%) received Pfizer, 36 patients (31%) Moderna, and 10 patients (9%) J&J. We observed a high-rate of seropositivity (86%) with 16 pts (14%) having a negative Spike IgG. Of the 86 minority patients included, 94% Blacks (30/32) and 87% (39/45) Hispanics showed seropositivity. The factors that contributed to significantly lower seroconversion rates included patients with Non-Hodgkin lymphoma (p=0.005), those who received cytotoxic chemotherapy (p=0.002), IVIG (p=0.01), CAR-T cell therapy (p=0.00002), and CD20 monoclonal antibodies (Ab) (p=0.0000008). Plasma cell neoplasms (p=0.02), immunomodulatory agents (p=0.01), and proteasome inhibitors (p=0.01) had significantly higher seroconversion rates, and those with a history of prior COVID-19 (11%, 12/106) had significantly higher antibody titers (p=0.0003). The positivity rate was 86% (37 seropositive, 6 seronegative) for autologous HSCT and 75% (3 seropositive, 1 seronegative) for allogeneic HSCT. No life-threatening AE were observed. We show high seroconversion rates after SARS-CoV-2 vaccination in non-White patients with hematologic malignancies treated with a wide spectrum of therapeutic modalities. Vaccination is safe, effective, and should be encouraged in most patients with hematologic malignancies. Our minorities based study could be employed as an educational tool to dispel myths and provide data driven evidence to overcome vaccine hesitancy.

/pdf/high-seroconversion-rates-amongst-black-and-hispanics-with-49tquq8jp2.pdf

High Seroconversion Rates Amongst Black and Hispanics With Hematologic Malignancies after SARS-CoV-2 Vaccination

With the advance of SARS-CoV-2 vaccines, the outlook for overcoming the global COVID-19 pandemic has improved. However, understanding of immunity and protection offered by the SARS-CoV-2 vaccines against circulating variants of concern (VOC) is rapidly evolving. We investigated the mRNA vaccine-induced antibody responses against the referent WIV04 (Wuhan) strain, circulating variants, and human endemic coronaviruses in 168 naive and previously infected people at three-time points. Samples were collected prior to vaccination, after the first and after the second doses of one of the two available mRNA-based vaccines. After full vaccination, both naive and previously infected participants developed comparable robust SARS-CoV-2 specific spike IgG levels, modest IgM and IgA binding antibodies, and varying degrees of HCoV cross-reactive antibodies. However, the strength and frequency of neutralizing antibodies produced in naive people were significantly lower than in the previously infected group. We also found that 1/3rd of previously infected people had undetectable neutralizing antibodies after the first vaccine dose; 40% of this group developed neutralizing antibodies after the second dose. In all subjects neutralizing antibodies produced against the B.1.351 and P.1 variants were weaker than those produced against the reference and B.1.1.7 strains. Our findings provide support for future booster vaccinations modified to be active against the circulating variants.

https://biorxiv.org/content/10.1101/2021.06.19.449100v1.full.pdf

SARS-CoV-2 mRNA Vaccine Induces Robust Specific and Cross-reactive IgG and Unequal Strain-specific Neutralizing Antibodies in Naïve and Previously Infected Recipients

With the availability of widespread SARS-CoV-2 vaccination, high-throughput quantitative anti-spike serological testing will likely become increasingly important. Here, we investigated the performance characteristics of the recently FDA authorized semi-quantitative anti-spike AdviseDx SARS-CoV-2 IgG II assay compared to the FDA authorized anti-nucleocapsid Abbott Architect SARS-CoV-2 IgG, Roche elecsys Anti-SARS-CoV-2-S, EuroImmun Anti-SARS-CoV-2 ELISA, and GenScript surrogate virus neutralization assays and examined the humoral response associated with vaccination, natural protection, and breakthrough infection. The AdviseDx assay had a clinical sensitivity at 14 days post-symptom onset or 10 days post PCR detection of 95.6% (65/68, 95% CI: 87.8-98.8%) with two discrepant individuals seroconverting shortly thereafter. The AdviseDx assay demonstrated 100% positive percent agreement with the four other assays examined using the same symptom onset or PCR detection cutoffs. Using a recently available WHO International Standard for anti-SARS-CoV-2 antibody, we provide assay unit conversion factors to international units for each of the assays examined. We performed a longitudinal survey of healthy vaccinated individuals, finding median AdviseDx immunoglobulin levels peaked seven weeks post-first vaccine dose at approximately 4,000 IU/mL. Intriguingly, among the five assays examined, there was no significant difference in antigen binding level or neutralizing activity between two seropositive patients protected against SARS-CoV-2 infection in a previously described fishing vessel outbreak and five healthcare workers who experienced vaccine breakthrough of SARS-CoV-2 infection – all with variants of concern. These findings suggest that protection against SARS-CoV-2 infection cannot currently be predicted exclusively using in vitro antibody assays against wildtype SARS-CoV-2 spike. Further work is required to establish protective correlates of protection for SARS-CoV-2 infection.

/pdf/anti-sars-cov-2-antibody-levels-are-concordant-across-1sa9ykwyys.pdf

Anti-SARS-CoV-2 antibody levels are concordant across multiple platforms but are not fully predictive of sterilizing immunity

BACKGROUND & AIMS: Silymarin, an extract from the seeds of the milk thistle plant Silybum marianum, has been used for centuries for the treatment of chronic liver diseases. Despite common use by patients with hepatitis C in the United States, its clinical efficacy remains uncertain. The goal of this study was to determine whether silymarin has in vitro effects on immune function that might have implications for its potential effect on hepatitis C virus (HCV)-induced liver disease. METHODS: Freshly isolated peripheral blood mononuclear cells (PBMC) and T cells from HCV-infected and uninfected subjects were tested in vitro for responses to nonspecific and antigenic stimulation in the presence and absence of a standardized preparation of silymarin (MK001). RESULTS: Minimal MK001 toxicity on PBMC was found at concentrations between 5 and 40 g/mL. MK001 dose dependently inhibited the proliferation and secretion of tumor necrosis factor (TNF)-, interferon (IFN)-, and interleukin (IL)-2 by PBMC stimulated with anti-CD3. In addition, MK001 inhibited proliferation by CD4 T cells to HCV, Candida, and tetanus protein antigens and by HLA-A2/HCV 1406‐1415-specific CD8 T cells to allogeneic stimulation. MK001 inhibited T-cell TNF- and IFN- cytokine secretion to tetanus and Candida protein antigens. Finally, MK001 inhibited nuclear factor-B transcriptional activation after T-cell receptor-mediated stimulation of Jurkat T cells, consistent with its ability to inhibit Jurkat T-cell proliferation and secretion of IL-2. CONCLUSIONS: Silymarin’s ability to inhibit the proliferation and proinflammatory cytokine secretion of T cells, combined with its previously described antiviral effect, suggests a possible mechanism of action that could lead to clinical benefit during HCV infection.

https://www.gastrojournal.org/article/S0016-5085(09)01662-X/pdf

Chihiro Morishima

Papers

Anti-SARS-CoV-2 antibody levels are concordant across multiple platforms but are not fully predictive of sterilizing immunity

BASIC—LIVER, PANCREAS, AND BILIARY TRACT Silymarin Inhibits In Vitro T-Cell Proliferation and Cytokine Production in Hepatitis C Virus Infection