Immunophenotype of peripheral blood lymphocytes following thermal injury in patients

Background: Severe immunosuppression occurs after large thermal burn and probably contributes substantially to patient morbidity and mortality.In this study we investigated the range and distribution of T-lymphocyte. Subsets CD3 (T cells) CD4 (T helper/inducer cell,.th ), CD8 (T suppressor /Cytotoxic cells ,TS/C), CD3 CD4/CD3CD8 ratio, CD19 (B cells) and CD16 (NK cells ) in patiens following thermal injury. Methods: Forty male, aging 18-60 years with major thermal injury were studied.The total body surface area of the burn injury, ranged from 30 to >70%. Whole blood samples were collected at three and seven days postburn. Partec flowcytometry system and triple color flowcytometry reagents (Dako Co), were used to evaluate peripheral blood lymphocytes population of patients admitted at the Motahary Burn Center in Tehran. Results: Compare to healthy controls, patients with burns have shown a significant reduction in relative number of CD3, CD4 and CD8 T cells at three and seven adys postburn.CD4/CD8 ratio were below normal range in three days and remained in normal range in seven days following injury. CD19 B cell populations were elevated in burn patients at both three and seven days. The number of CD16 NK cells were significantly declined in three days and moderately increased on day seven, following injury. Thus, the data showed that thermal burn injury suppressed T-lymphocyte subsets proliferation in various days .In addition, all compartments of showed phenotypic changes in the 3th and seventh days after burn, in different groups of age. Thermal burn injury suppressed T cell subsets proliferation on day 3 and 7 postburn, when compared to normal controls. (P _ <0.05) at 3 and 7 days post burn. Conclusion: Significant changes in lymphocytes population could be an important factor in immunosuppression and development of sepsis in thermal burn patients.