Chronic lymphocytic leukemia specific T-cell subset alterations are clone-size dependent and not present in monoclonal B lymphocytosis.
In patients with chronic lymphocytic leukemia (CLL), effector and memory CD4 + and CD8 + T cells are expanded. We investigated whether these CLL specific T-cell expansions also occur in monoclonal B lymphocytosis (MBL), the pre-leukemic state of CLL, which is currently distinguished from CLL by an arbitrarily chosen cut-off value of CD19 of 5.0 × 10(9)/L. Whereas an increase in effector and memory CD4 + and CD8 + T cells was found in CLL, these expansions could not be found in MBL. Although a significant correlation was found between absolute B cell count (CD19) and T cell numbers, correlation coefficients were rather low. Therefore, we analyzed whether an optimal threshold for CD19 number could be defined which best related to an expansion of T cells. The B-cell threshold that best predicted expansion of CD3 +, CD4 + and CD8 + T cells, respectively, was 10 × 10(9)/L. Our study indicates that a higher cut-off value than the current 5.0 × 10(9)/L relates better to the biological impact of CLL.
Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands.
G Doreen
GD
te Raa
Sanne H
SH
Tonino
Ester B M
EB
Remmerswaal
Arend Jan
AJ
van Houte
Harry R
HR
Koene
Marinus H
MH
van Oers
Arnon P
AP
Kater
D018941:Antigens, CD19 / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D017252:CD3 Complex / Q000032:analysis; D006801:Humans; D007156:Immunologic Memory; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology*; D008218:Lymphocytosis / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D018941:Antigens, CD19; D017252:CD3 Complex