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2.
Cell Rep Med ; 2(7): 100354, 2021 07 20.
Article En | MEDLINE | ID: mdl-34250512

Ending the COVID-19 pandemic will require long-lived immunity to SARS-CoV-2. Here, we evaluate 254 COVID-19 patients longitudinally up to 8 months and find durable broad-based immune responses. SARS-CoV-2 spike binding and neutralizing antibodies exhibit a bi-phasic decay with an extended half-life of >200 days suggesting the generation of longer-lived plasma cells. SARS-CoV-2 infection also boosts antibody titers to SARS-CoV-1 and common betacoronaviruses. In addition, spike-specific IgG+ memory B cells persist, which bodes well for a rapid antibody response upon virus re-exposure or vaccination. Virus-specific CD4+ and CD8+ T cells are polyfunctional and maintained with an estimated half-life of 200 days. Interestingly, CD4+ T cell responses equally target several SARS-CoV-2 proteins, whereas the CD8+ T cell responses preferentially target the nucleoprotein, highlighting the potential importance of including the nucleoprotein in future vaccines. Taken together, these results suggest that broad and effective immunity may persist long-term in recovered COVID-19 patients.


Antibodies, Viral/blood , Antibody Formation , COVID-19/immunology , Immunologic Memory , Spike Glycoprotein, Coronavirus/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Longitudinal Studies , Male , Memory B Cells , Memory T Cells , Middle Aged , Young Adult
3.
medRxiv ; 2021 Jun 18.
Article En | MEDLINE | ID: mdl-33948610

Ending the COVID-19 pandemic will require long-lived immunity to SARS-CoV-2. Here, we evaluate 254 COVID-19 patients longitudinally up to eight months and find durable broad-based immune responses. SARS-CoV-2 spike binding and neutralizing antibodies exhibit a bi-phasic decay with an extended half-life of >200 days suggesting the generation of longer-lived plasma cells. SARS-CoV-2 infection also boosts antibody titers to SARS-CoV-1 and common betacoronaviruses. In addition, spike-specific IgG+ memory B cells persist, which bodes well for a rapid antibody response upon virus re-exposure or vaccination. Virus-specific CD4+ and CD8+ T cells are polyfunctional and maintained with an estimated half-life of 200 days. Interestingly, CD4+ T cell responses equally target several SARS-CoV-2 proteins, whereas the CD8+ T cell responses preferentially target the nucleoprotein, highlighting the potential importance of including the nucleoprotein in future vaccines. Taken together, these results suggest that broad and effective immunity may persist long-term in recovered COVID-19 patients.

4.
Cell Host Microbe ; 29(4): 516-521.e3, 2021 04 14.
Article En | MEDLINE | ID: mdl-33798491

The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies. We compared antibody binding and live virus neutralization of sera from naturally infected and Moderna-vaccinated individuals against two SARS-CoV-2 variants: B.1 containing the spike mutation D614G and the emerging B.1.351 variant containing additional spike mutations and deletions. Sera from acutely infected and convalescent COVID-19 patients exhibited a 3-fold reduction in binding antibody titers to the B.1.351 variant receptor-binding domain of the spike protein and a 3.5-fold reduction in neutralizing antibody titers against SARS-CoV-2 B.1.351 variant compared to the B.1 variant. Similar results were seen with sera from Moderna-vaccinated individuals. Despite reduced antibody titers against the B.1.351 variant, sera from infected and vaccinated individuals containing polyclonal antibodies to the spike protein could still neutralize SARS-CoV-2 B.1.351, suggesting that protective humoral immunity may be retained against this variant.


Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Binding Sites , COVID-19/prevention & control , Humans , Neutralization Tests , Receptors, Virus/chemistry
5.
bioRxiv ; 2021 Feb 22.
Article En | MEDLINE | ID: mdl-33655254

The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies to neutralize these variants. We compared antibody binding and live virus neutralization of sera from naturally infected and spike mRNA vaccinated individuals against a circulating SARS-CoV-2 B.1 variant and the emerging B.1.351 variant. In acutely-infected (5-19 days post-symptom onset), convalescent COVID-19 individuals (through 8 months post-symptom onset) and mRNA-1273 vaccinated individuals (day 14 post-second dose), we observed an average 4.3-fold reduction in antibody titers to the B.1.351-derived receptor binding domain of the spike protein and an average 3.5-fold reduction in neutralizing antibody titers to the SARS-CoV-2 B.1.351 variant as compared to the B.1 variant (spike D614G). However, most acute and convalescent sera from infected and all vaccinated individuals neutralize the SARS-CoV-2 B.1.351 variant, suggesting that protective immunity is retained against COVID-19.

6.
Am J Mens Health ; 11(4): 834-844, 2017 07.
Article En | MEDLINE | ID: mdl-26400715

Alcohol, the most widely used substance among men who have sex with men (85%), remains an important factor in HIV research among this high-risk population. However, research on alcohol use among Black and Latino men who have sex with men (BLMSM), a population disproportionately affected by HIV in the United States, is limited and inconclusive. This study explored sociodemographic and HIV risk with daily heavy and low-risk drinking patterns among BLMSM. BLMSM ( N = 188) aged 18 to 40 years were recruited through social media, local colleges, heteronormative clubs, private men's groups, gay establishments, and organized events in Los Angeles County. Participants completed self-administered questionnaires. Fisher's exact tests revealed significant relationships between drinking patterns and condomless insertive anal intercourse ( p = .001), race ( p < .001), age ( p = .02), and perception of alcohol-related HIV risk ( p = .007). The Fisher's exact tests findings for age held true in the multiple regression model ( p = .014). Findings suggest that BLMSM who engage in higher risk drinking also engage in alcohol-related HIV risk. Culturally competent interventions should consider including a combined focus to explore the synergy between risky drinking patterns and HIV risk among BLMSM.


Alcohol Drinking/epidemiology , Black or African American/statistics & numerical data , HIV Infections/epidemiology , Hispanic or Latino/statistics & numerical data , Homosexuality, Male/statistics & numerical data , Risk-Taking , Adult , Comorbidity , Humans , Los Angeles , Male , Risk Factors , Young Adult
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