HIV skews the SARS-CoV-2 B cell response toward an extrafollicular maturation pathway (preprint)

Background: HIV infection dysregulates the B cell compartment, affecting memory B cell formation and the antibody response to infection and vaccination. Understanding the B cell response to SARS-CoV-2 in people living with HIV (PLWH) may explain the increased morbidity, reduced vaccine efficacy, reduced clearance, and intra-host evolution of SARS-CoV-2 observed in some HIV-1 coinfections. Methods: We compared B cell responses to COVID-19 in PLWH and HIV negative (HIV-ve) patients in a cohort recruited in Durban, South Africa, during the first pandemic wave in July 2020 using detailed flow cytometry phenotyping of longitudinal samples with markers of B cell maturation, homing and regulatory features. Results: This revealed a coordinated B cell response to COVID-19 that differed significantly between HIV-ve and PLWH. Memory B cells in PLWH displayed evidence of reduced germinal center (GC) activity, homing capacity and class-switching responses, with increased PD-L1 expression, and decreased Tfh frequency. This was mirrored by increased extrafollicular (EF) activity, with dynamic changes in activated double negative (DN2) and activated naive B cells, which correlated with anti-RBD-titres in these individuals. An elevated SARS-CoV-2 specific EF response in PLWH was confirmed using viral spike and RBD bait proteins. Conclusions: Despite similar disease severity, these trends were highest in participants with uncontrolled HIV, implicating HIV in driving these changes. EF B cell responses are rapid but give rise to lower affinity antibodies, less durable long-term memory, and reduced capacity to adapt to new variants. Further work is needed to determine the long-term effects of HIV on SARS-CoV-2 immunity, particularly as new variants emerge.

HIV infection alters SARS-CoV-2 responsive immune parameters but not clinical outcomes in COVID-19 disease (preprint)

HIV infection alters the immune response and can compromise protective immunity to multiple pathogens following vaccination. We investigated the impact of HIV on the immune response to SARS-CoV-2 using longitudinal samples from 124 participants from KwaZulu-Natal, South Africa, an area of extremely high HIV prevalence. 44% of participants were people living with HIV (PLWH) and commonly had other co-morbidities, including obesity, hypertension, and diabetes. The majority of PLWH but not HIV negative participants showed CD8 T cell expansion above the normal range post-SARS-CoV-2. Yet, in participants with HIV suppressed by antiretroviral therapy (ART), CD8 expansion was associated with milder COVID-19 disease. There were multiple differences in T cell, B cell, and natural killer cell correlations in PLWH compared to HIV negative participants, including lower tissue homing CXCR3+ CD8 T cells in the presence of SARS-CoV-2 RNA in PLWH but not HIV negative and a pronounced early antibody secreting cell (ASC) expansion in HIV negative but not PLWH. These changes were COVID-19 associated: low CXCR3 correlated with increased COVID-19 disease severity across groups, and high ASC correlated with increased disease severity in HIV negative participants and waned when SARS-CoV-2 was cleared. Despite the altered response of immune cell subsets, COVID-19 disease in PLWH was mostly mild and similar to HIV negative participants. This likely reflects the heterogeneity of an effective COVID-19 immune response. Whether the differences in immune cell dynamics in PLWH will lead to different long-term consequences or compromise vaccination is yet to be determined.