Foxp3 expressing CD4+ CD25+ and CD8+CD28- T regulatory cells in the peripheral blood of patients with lung cancer and pleural mesothelioma.

The role of T regulatory (Treg) cells in human cancer has not yet been clarified. We assessed the presence and function of CD4+ and CD8+ Treg cell subsets in the peripheral blood of patients with lung cancer (LC) and pleural mesothelioma (PM). We found a low but significant increase in the number of CD4+ T cells with phenotype and functional features of Treg cells in LC patients compared to normal healthy controls (NHC). Furthermore, total CD4+ T cells from LC pa- tients proliferated less than cells from controls, suggesting that the increase in the CD4+ Treg cell pool has func- tional importance. LC patients also showed an expansion of the CD8+CD28- T cell subset and these cells ex- pressed Foxp3 mRNA, as recently observed in alloanti- gen-specific CD8+CD28- T suppressor cells. No varia- tion of peripheral Treg cell subsets was found in patients with PM, a disease with a predominantly localized nature. However, the lack of correlation between cancer stage and the number or the function of peripheral Treg cells in LC patients refuted the hypothesis that these cells are in- volved in tumor spreading. A possible involvement of the peripheral Treg cell pool in cancer development and/or in inducing systemic immunosuppression in LC patients can be hypothesized

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed