ABSTRACT
Background and aim: Cytomegalovirus [CMV] infects the majority of human population in their life time and triggers strong immune responses from all arms of the immune system. However the cellular immune response is the major mechanism by which CMV replication is controlled. CMV-specific CD4[+] T cells have a substantial role in maintenance of CMV-specific CD8+ T cell response. The aim of the study was an overview of CD4[+]T cell response to CMV in healthy donors and patients with hematological malignancies
Methods: In this review, abstract or full text articles related to CMV-specific CD4[+] T cell response, published during 1990 until 2010, were collected from the Medline. The Persian articles were searched through the IranMedex database and used if they were appropriate
Results: In chronic infection, the CMV-specific CD4[+] T cells secrete interferon-gamma [IFN-gamma], tumor necrosis factor-alpha [TNF-alpha] and interleukin-2 [IL-2]. CMV-specific CD4[+] response increases with age and the response has been up to 32% with intracellular cytokine detection technique. The cells have also lower activation threshold. The CMV-specific CD4[+] T cell response increases and comprises up to 47% of whole CD4[+] compartment in patients who received hematopoietic stem cells transplants. It was up to 44% in chronic lymphocytic leukemia patients and broad phenotyping alterations have also been observed in relation to CMV-seropositivity
Conclusion: Considering the high level of CMV-specific CD4[+] T cell response, the viral replication can be controlled and the reactivation can be prevented. Because of the possibility of intracellular cytokine, it is now possible to determine the phenotype of the cells. Therefore, CMV has served as an excellent model for effectors-memory phenotype studies and could be a possible tool in the way to achieve immunotherapy