Patients with immunodeficiency are at higher risk of severe disease and death following SARS-CoV-2 infection compared to the general population. Here, we describe humoral and cellular immune responses in 5 patients with immunodeficiency, 2 patients with multiple sclerosis, 1 patient with chronic lymphocytic leukemia (CLL), 1 patient with Good's syndrome, and 1Human Immunodeficiency Virus (HIV) positive with developed Acquired immunodeficiency syndrome (AIDS)- patient. T-cell responses were evaluated using the QuantiFERON SARS-CoV-2 assay following incubation with the SARS-CoV-2 Ag1, Ag2, and Ag3 viral antigens. Immunophenotyping of CD4+ and CD8+ T cells and CD19+ and CD20+ B cells was determined by flow cytometry. All studied immunocompromised patients or those with acquired immune dysregulation patients showed reduced cellular immune responses (release of interferon (IFN)-g) to SARS-CoV-2 antigens than healthy controls [patients; Ag1, Ag2 and Ag3 and Nil (Median 5-95% percentile) (12 (1-95), 12 (1.5-78), 13.5 (12-95) and 3 (1-98) U/mL)], controls; Ag1, Ag2 and Ag3 and Nil (Median 5-95% percentile) 24.5 (7-89), 65 (31-173), 53.5 (13-71.5) and 3 (1-14) U/mL)]. The frequency of peripheral blood B cells was also reduced in these patients compared to healthy control subjects. T-cell-dependent antibody responses require the activation of B cells by helper T cells. Reduced B cell numbers in immunocompromised patients infected with SARS-CoV-2 indicate the need for these patients to take additional precautions to prevent COVID-19 infection.
Keywords: COVID-19; Immunologic deficiency syndromes; SARS-COV-2; Vaccine.