A Comparison of Immune Functionality in Viral versus Non-Viral CFS Subtypes.

Participants with CFS were grouped into viral and non-viral onset fatigue categories and assessed for differential immunological marker expression. Peripheral Blood Mononuclear Cells were assessed for differential phenotypic expression of surface adherence glycoproteins on circulating lymphocytes. The flow cytometric analysis employed fluorescent monoclonal antibody labeling. The viral in comparison to the non-viral group demonstrated significant elevations in several Th1 type subsets including: the percentage and number of CD4+ cells, the percentage and number of CD2+CD26+ cells, the percentage and number of CD2+CD4+CD26+ cells, the percentage and number of CD4+ CD26+ cells, and the percentage of Th2 naïve cells (CD4+ CD45RA+CD62L+). Of the remaining significant findings, the non viral group demonstrated significant elevations in comparison to the viral group for the following Th1 type subsets: the percentage of CD8+ cells, the percentage of T-cytotoxic suppressor cells (CD3+8+), and the percentage and number of Th1 memory cells (CD8+CD45RA-CD62L-). The viral group demonstrated a pattern of activation that differed from that of the group with a non-viral etiology, as evidenced by an elevated and out of range percentage and number of CD4+ cells, the percentage of CD2+CD26+, and the percentage of Th2 naïve cells (CD4+CD45RA+CD62L+). Both groups demonstrated reduced and out of range Natural Killer Cell Cytotoxicity and percentage of B-1 cells (CD5+CD19). In addition, both groups demonstrated an elevated and out of range percentage of CD2+CD8+CD26+, percentage of the Th1 memory subset (CD4+CD45RA-CD62L-), the percentage of Th1 memory and naïve cells (CD8+CD45RA-CD62L-, CD8+CD45RA+CD62L-), the percentage and number of Th2 memory cells (CD4+CD45RA-CD62L+), and the percentage of Th2 memory and naïve cells (CD8+CD45RA-CD62L+, CD8+CD45RA+CD62L+). These findings imply that the homeostatic mechanism responsible for the regulation of the Th1 (cell mediated) and Th2 (humoral) immune responses is disturbed in CFS. The implications of these findings are discussed.