[High level of CMV -specific CD4[+] and CD8[+] cells immune response and correlation between them in B-cell Chronic Lymphocytic Leukemia Patients]

ABSTRACT

Chronic lymphocytic leukemia [CLL] is characterized by a monoclonal proliferation of lymphocytes mainly B cells [B-CLL] in the blood and bone marrow. Morphological and functional abnormalities of T cells and monoclonality of them have been documented in CLL. Such expanded cells may be specific for recognition of pathogens. Cytomegalovirus [CMV] is most likely involved in this phenomenon in CLL. CMV infection causes a high level of immune response in immunodeficient patients. In this study, the association between expanded T cells and the immune responses of CWV-specific CD4[+] and CD8[+] cells in B-CLL was investigated. This was a cross sectional study and the study group were 41 CMV seropositive B-CLL patients and 35 CMV seropositive healthy donors [control group]. The level of CMV-specific CD4[+] and CD8[+] cells immune responses were detected by intracellular cytokine response to antigenic activation and CMV tetramer respectively. The level of CMV-specific CD4[+] cells responses was significantly higher in patients with a median of 10.99% and 1 1% for IFN-y and TNF-a producing CD4+T cells respectively than age-matched controls with a median of 4.3% and 4.6 [p= 0.0001 for IFN-[gamma] and p= 0.003 for TNF-[alpha]]. The level of CMV-specific CD8[+] cells immune responses was also higher in patients compared to control group [p= 0.03 for NLV]. There was a positive correlation between the level of CD4[+] and CD8[+] cells immune responses [p=0.009]. These results show the deep influence of CMV infection and the immune response to it in T-cell alteration in CLL patients. The increased level of CMV-specific T cells may be the cause of increased level of absolute T cells in these patients