Features of T-cell and humoral immunity of patients with acute coronary syndrome, with and without COVID-19, depending on/peripheral blood B-lymphocytes with the phenotype CD3–CD19+CD5+ level

The aim of the work was to assess the T-cell and humoral immune arms in patients with acute coronary syndrome (ACS) recovered from or not exposed to COVID-19. 86 men with ACS aged 40 to 65 years old, who suffered or not exposed to COVID-19, which required stenting of coronary arteries, were examined. Depending on the peripheral blood B-lymphocyte CD3–CD19+CD5+ level and the former COVID-19 history, all patients were divided into 6 groups. Of the previously COVID-19 exposed subjects CD3–CD19+CD5+ lymphocytes were at: reduced (group 1), normal (group 2), increased (group 3) level. COVID-19 unexposed subjects had CD3–CD19+CD5+ lymphocyte level: reduced (group 4), normal (group 5), increased (group 6). The most severe clinical manifestations were observed in group 1: with a larger rate of stent thrombosis and increased mortality. In absolute numbers, T-lymphocytes were significantly lower in group 1 compared to other groups, except group 4. The lowest both relative and absolute T-helper cell counts were recorded in covid-19 patients, with reduced CD3–CD19+CD5+ cell level. NK-lymphocytes both in relative and absolute level were significantly (p 0.05) higher in patients who suffered from COVID-19 as compared to those in patients unexposed to previous COVID-19. Percentage of late-activation T-regulatory cells was minimal in patients with former COVID-19 along with high B-lymphocyte CD3–CD19+CD5+ level, which significantly (p 0.05) differed from those in subjects lacking former COVID-19 history. In addition, significantly lower B-lymphocyte CD3–CD19+CD5– level was found in group 1 and 4. The IgM level peaked in group 5 — subjects lacking former COVID-19 history and having normal CD3–CD19+CD5+ cell level that significantly differed in comparison with that of in group 1, 2, 3. At the same time, the maximum value of IgG level was recorded in COVID-19 patients with normal CD3–CD19+CD5+ cells, and significantly differed from those found in group 5 and 6. C1-inhibitor level was higher in group 3 that significantly differed from that in other groups. SARS-CoV-2-specific IgG and IgM levels were significantly higher in COVID-19-positive vs. COVID-19-negative patients. Conclusion. In patients who have suffered COVID-19 with low B-lymphocyte CD3–CD19+CD5+ level, a significantly compromised immune protection was noted in comparison with other groups: a decline in total T-lymphocyte, T-helper, early- and late-activation T-lymphocyte, T-regulatory cell, B-lymphocyte CD3–CD19+CD5– levels, which was associated with a more severe disease course characterized by stent thrombosis and large mortality.