Association of follicular helper T and follicular regulatory T cells with severity and hyperglycemia in hospitalized COVID-19 patients.

We aimed to determine the levels of follicular helper T (Tfh) and follicular regulatory T (Tfr) cells in COVID-19 patients and determine whether their levels correlated with disease severity and presence of hyperglycemia. This study was carried out in 34 hospitalized COVID-19 patients and 20 healthy controls. Levels of total circulating Tfh, inducible T-cell costimulator (ICOS)+ activated Tfh, and Tfr cells were assessed in all participants by flow cytometry. Total CD4+CXCR5+ Tfh cells and ICOS+Foxp3-activated Tfh cells increased and ICOS+Foxp3+ Tfr cells decreased in COVID-19 patients, especially in diabetic patients and those with severe disease. Activated ICOS+ Tfh cells were directly correlated with lactate dehydrogenase, D-dimer, ferritin, and respiratory rate and inversely correlated with the partial pressure of carbon dioxide. COVID-19 is associated with marked activation of Tfh cells and a profound drop in Tfr cells, especially in severe and diabetic patients. Future studies on expanded cohorts of patients are needed to clarify the relationship between SARS-CoV-2 and acute-onset diabetes.

Impact of CD39 expression on CD4+ T lymphocytes and 6q deletion on outcome of patients with chronic lymphocytic leukemia.

OBJECTIVE/BACKGROUND: Chronic lymphocytic leukemia is one of the commonest leukemias affecting adults. CD39 inhibits T-cell and Natural killer (NK) cell responses by hydrolyzing adenosine triphosphate and adenosine diphosphate, suppressing the immune system. We investigated expression of CD39 on CD4+ T Lymphocytes in chronic lymphocytic leukemia (CLL) patients and its relationship with deletion 6q, its association with disease stage and survival. METHODS: Thirty CLL patients and 20 matched controls were included in the study. Bone marrow studies with immunophenotyping, CD39, CD38, and ZAP-70, and detection of del 6q by FISH were performed. RESULTS: CD39+ CD4+ T helper cells in CLL patients were significantly expressed compared with the controls (p < .001). Levels of CD39+ CD4+ T cells were significantly expressed in high risk CLL patients. Del 6q was detected in 63.3% of patients and it correlated with CD39, CD38, and ZAP-70, and advanced stage disease. There was a significant relation between response to treatment and CD39 expression and del 6q, also there was a significant difference in overall survival (OS) between patients with and without Del 6q. CONCLUSION: CD39 expression on CD4+ Tcells and del 6q act as prognostic markers in CLL. Blocking or inhibition of CD39 may be a target for new immune therapy for CLL.