Lymphocyte subset reference intervals in blood donors from northeastern Brazil

Alex J L Torres, Patrícia Cisneiros, Rosa Guedes, Maria Fernanda R Grassi, Roberto Meyer, Maria T Bendicho, Tais G S L Lopes, Gabriela Félix, Eduardo M Netto, Carlos Brites, Kiyoko Abe-Sandes, Claudio Brandão, Neuza Alcantara-Neves, Songeli M Freire

The reference intervals for leukocytes and lymphocytes currently used by most clinical laboratories present limitations as they are primarily derived from individuals of North American and European origin. The objective this study was to determine reference values for peripheral blood B lymphocytes, T lymphocyte subsets (CD4+, CD8+, naïve, memory, regulatory, TCRαβ and TCRγδ+) and NK cells from blood donors in Salvador-Bahia, Brazil. The proportion of included male subjects was 73.7% and the median ages of males (34) and females (35) were found to be similar. Absolute counts total lymphocytes subsets to both gender was 1,956 (1,060-4,186) cells and relative values 34%. The T CD4+ and T CD8+ lymphocytes relative values was 51% (20-62) and 24% (9-28), respectively. The most statistically significant finding observed was a higher percentage of B lymphocytes (p=0.03) in females. Commonly cited subset reference intervals were found to be consistent with values in several populations from different geographic areas.