Novel human T-cell proliferation markers

Abstract

The standard method to study T-cell proliferation is flow cytometric evaluation of the intracellular Ki67 expression. However, this analysis requires preliminary cell fixation and permeabilization that limits further research. The aim of the present work was to evaluate the possibility of using the surface molecule CD71 as an alternative marker for T-cell proliferation. Frequencies of CD71+ and Ki67+ T-lymphocytes and candidate proliferation markers’ expression levels were studied in unstimulated and phytohemagglutinin-stimulated human peripheral blood cells using flow cytometry. We found that stimulation increases the frequency and level of Ki67 and CD71 expression in CD4+ and CD8+ T-cells. We revealed a strong positive correlation between the two molecules in different T-cell subsets. It should be noted that all Ki67+ T-cells expressed CD71, while the majority of CD71+ cells did not express Ki67. Based on the data obtained, one can conclude that CD71 is not a complete analog of Ki67, but it can be used for investigations of activated/cycling T-lymphocytes.