Anti cd4 rd1

Fresh whole blood was stained with anti-CD45-FITC, anti-CD3-PC5, anti-CD4-RD1, anti-CD8-ECD (CYTO-STAT tetraCHROME), anti-CD45-FITC, anti-CD3-PC5, anti-CD56-RD1, and anti-CD19 ECD monoclonal antibodies (CYTO-STAT tetraCHROME; all from Beckman Coulter, Milan, Italy). After the lysis of the red blood cells, the absolute CD3 + (Tcells), CD3 + CD4 + (Helper T cells), CD3 + CD8 + (Suppressor T cells), CD3-CD56 + (NK cells) and CD19 + (B cells) (cells/μL) were determined by flow cytometry (Navios, Beckman Coulter) using Flow-Count Fluorospheres in a single platform and lysed no-wash preparation. The gating strategy was set up on CD45 + and side scatter (SSC).

Based on hsTnI levels, we divided COVID-19 patients into hsTnI-L and hsTnI-H groups, and healthy physical examiners were selected as the control group. Lymphocyte subsets were compared among the three groups.
Peripheral blood samples were collected in ethylenediaminetetraacetic acid K2 (EDTA-K2) collection tubes for lymphocyte subset and hemoglobin A1c detection. Antibodies, including anti-CD3-PC5, anti-CD4-RD1, anti-CD8-ECD, anti-CD45-FITC, anti-CD56-RD1, and anti-CD19-ECD, were purchased from Beckman Coulter (USA). CD3⁺CD4⁺ cells represent T helper cells, CD3+CD8+ cells represent T suppressor cells, and CD4⁺CD25⁺CD127^Dim cells represent T regulatory cells, respectively. Lymphocyte subsets were detected using a flow cytometer (FC500MCL; Beckman Coulter, USA). Hemoglobin A1c was detected using a glycated hemoglobin analyzer (Premier Hb9210, USA).