[Significance of CMV-seropositivity in the alterations of CD4[+] T- cell subsets and expression of their phenotyping markers in B-cell chronic lymphocytic leukemia]

ABSTRACT

B-cell chronic lymphocytic leukemia [B-CLL] is a B-cell malignancy which has been associated with a variety of abnormalities in non-malignant T cells. Viral antigens are able to produce profound alterations in T-cell and cytomegalovirus [CMV] has been involved in T-cell abnormalities in healthy elderly individuals. Therefore, the relationship between these changes and CMV was studied in CLL patients. This was a cross sectional study and included 79 B-CLL patients [41 CMV seropositive and 38 CMV seronegative]. The cell counting was done by Coulter cell counter. The T-cell subgroups and cell phenotype were studied by monoclonal antibodies and flow cytometry. The secretion of cytokine was detected by intracellular cytokine staining post stimulation and short time culture. CD8[+] and CD4[+]CD8[dim] T cell subgroups were significantly more in CMV[+] patients than CMV negatives [P<0.01]. IFN-gamma producing T cells were significantly more in CMV [+] patients, whereas IL-2 producing T cells were more in CMV[-] patients [P<0.05 and P<0.01, respectively]. A prominent decrease was seen in the expression of CD27, CD28, CD45RA and CCR7 in CMV[+] patients, whereas CD45RO and CD57 showed significant rise [P<0.05 and P<0.001, respectively]. CMV seropositivity causes broad alterations in T-cells and expression of terminally differentiated phenotype in B-CLL patients. Therefore, such profile in B-CLL is highly related to CMV seropositivity