Study of the Hemodialysis on Immunomodulation of TH1/TH2 balance

ABSTRACT

Patients on chronic intermittent haemodialysis [HD] show an impaired cellular and humoral immune response that clinically appears with frequent infectious complications and low vaccination responses. This immune defect strongly correlates with reduced in vitro proliferative responses of T cells. The defect is localized in antigen presenting cells, which show a decreased co-stimulatory activity. Furthermore, the impaired immune response correlates with an increased production of pro-inflammatory cytokines. In response to primary, activation, CD4 positive T helper [Th] cells mainly differentiate into either Th1 or Th2 cells. Th1 cells support cell mediated immunity whereas Th2 cells enhance humoral immune responses. Since both types of responses mutually inhibit each other, the impaired humoral immune response seen in HD patients could either be due to a reduced number of Th2 cells or to a predominant Th1 response. The current study was to analyze the outcome of the Th1 or Th2 cell responses in HD patients compared with healthy controls and to place them in the context of the altered cellular characteristics and impaired immune status seen in HD patients. The study protocol was approved in 50 Patients in Damnhour National Medical Institute. In HD patients, a significantly higher percentage of CD4 cells are characterized by a Th1-type cytokine secretion pattern compared with healthy controls. Our findings contribute to a better understanding of the pathogenesis of impaired cellular immune functions in dialysis patients. They provide a link between overproduction of pro-inflammatory cytokines [IL-12] and imbalanced T-cell activation