Persons with HIV Develop Spike-Specific Lymph Node Germinal Center Responses following SARS-CoV-2 Vaccination

Area of Science:

• Immunology
• Virology
• Vaccinology

Background:

• COVID-19 disproportionately impacts persons with HIV (PWH), particularly where SARS-CoV-2 vaccines are scarce.
• PWH often have altered immune responses to vaccines, with abnormal lymph node structure potentially hindering germinal center (GC) formation.
• It remains unclear if lymph node abnormalities in PWH impede antigen-specific GC responses post-vaccination.

Purpose of the Study:

• To investigate the capacity of persons with HIV (PWH) to mount antigen-specific germinal center (GC) responses in draining lymph nodes following SARS-CoV-2 vaccination.
• To compare immune responses in PWH receiving mRNA vaccines versus Ad26.COV2.S vaccines.

Main Methods:

• Longitudinal collection of blood and fine needle aspirate samples from the draining lymph node before and after SARS-CoV-2 vaccination.
• Analysis of a prospective, observational cohort of 11 PWH on antiretroviral therapy.
• Assessment of spike-specific antibodies, B cells, T cells, GC B cells, and T follicular helper cells in blood and lymph node samples.

Main Results:

• Both mRNA vaccine recipients showed spike-specific antibodies, B cells, T cells in blood, and GC B/T follicular helper cell responses in lymph nodes.
• All Ad26.COV2.S vaccine recipients developed spike-specific antibodies in blood.
• Only one of six Ad26.COV2.S recipients exhibited detectable spike-specific GC B and T follicular helper cell responses in the draining lymph node.

Conclusions:

• Persons with HIV (PWH) are capable of mounting antigen-specific germinal center (GC) immune responses in draining lymph nodes after SARS-CoV-2 vaccination.
• The study suggests variability in GC response induction depending on the vaccine type (mRNA vs. Ad26.COV2.S).
• Further research is needed to identify factors contributing to the less frequent GC response observed in Ad26.COV2.S recipients within this PWH cohort.