Different expression of CD180, CD284 and CD14 receptors on the CD19+ subpopulation of normal and B-CLL lymphocytes.

Abstract

Numerous experimental data indicate that B-CLL development and progression are influenced by antigenic pressure. It can not be excluded that these antigens may originate from bacteria and viruses. Toll like receptors (TLRs) interact with pathogen associated molecular patterns as part of innate immunity. TLRs are currently used to target different subclasses of B-cell leukemia, and TLR agonists are being evaluated in clinical trials. It is little known regarding the repertoire and function of TLR in B-CLL. The aim of the study was to assess the CD180, CD284 and mCD14 levels in CD19+ subpopulation of B-CLL peripheral blood lymphocytes and compare them with respective levels in the normal B-cells of adult volunteers, before and after LPS stimulation. We investigated the percentage of the CD19+CD180+, CD19+CD284+, CD19+CD14+ cells and the mean fluorescence intensity (MFI) of CD180, CD284 and CD14 antigens among CD19+ B-CLL as well as in the normal B cells for comparison. MFI analysis revealed that CD180, CD284 and CD14 expression was higher on normal B cells then on CD19+ B-CLL (MFI CD180: 99.16 vs. 25.3, MFI CD284: 7.37 vs. 5.79 and MFI CD14 25.07 vs. 8.32). After 24-hour LPS activation of B-cells, CD180 MFI appeared to decrease, in both healthy and B-CLL patients. CD284 MFI in healthy controls decreased after LPS stimulation while slight increase of MFI was observed in leukemic cells. CD14 MFI in leukemic cells was moderately higher after LPS in comparison to CD14 MFI without LPS stimulation, whereas CD14 MFI in normal CD19+ cells after LPS stimulation decreased over three times. Variations observed in expression of both normal and leukemic receptors may be due to their different sensitivity to antigenic stimulation.