Immune recovery and the role of recent thymic emigrated T lymphocytes after pediatric hematopoietic stem cell transplantation.

Background Aims: Adequate re-establishment of thymopoiesis is critical for long-term immune reconstitution after hematopoietic cell transplantation (HCT), potentially impacting patient survival rates. This study aimed to evaluate immune reconstitution in pediatric HCT recipients by quantifying recent thymic emigrants (RTEs), specifically CD3CD31CD45RA cells.

Methods: We conducted a retrospective analysis of 186 pediatric patients transplanted between 2013 and 2020, undergoing their first allogeneic HCT, who were alive in the first 100 days after transplantation with immune recovery evaluation at three time points: day 100, day 180 and day 360 after HCT.

Evaluation of lymphocyte count, T-cell subsets and neutrophil-to-lymphocyte ratio as early predictors for severity and outcome of COVID-19 disease-a report from a highly complex hospital in Brazil.

Introduction: Lymphopenia is a laboratory marker of poor prognosis and severity of disease in the SARS-CoV-2 infection. This study aims to describe the immune profile of a Brazilian population.

Methods: A total of 121 consecutive patients with severe acute respiratory syndrome (SARS) were analyzed between April and June 2020.