Function and Phenotype of Lymphocytes in Normal and Inflamed Appendix in Appendicitis Patients

Appendicitis is one of the most common abdominal inflammatory diseases. The function of appendix is not clearly defined. In this study to understand the immunological function of the appendix, we investigated the function and phenotypic pattern of lymphocyte in appendix of patients with normal and inflamed appendix tissue. Appendix tissue and appendiceal mononuclear cells obtained from 81 patients (mean age; 23±10.5), who was clinicallysuspected of having appendicitis were collected. Based on histopathological examination, twenty-five patients had normal appendix while 40 and 16 were diagnosed with suppurative and gangrene appendicitis, respectively. The phenotypic characteristics of lymphocyte subsets in appendix was analyzed using three color-flow cytometry. In addition, the proliferative response of tissue mononuclear cells was assayed by MTT method. A significant difference (p<0. 01) was observed in the percentage of CD19/HLA-DR, HLA-DR and CD19 cellsfrom patients suffering from suppurative appendicitis in comparison with the patients having normal appendix or gangrene one. There was also a significant difference (p<0.01) in the proliferative responses of the appendiceal mononuclear cells to PHA and LPS from pathients with suppurative appendicitis when compare with other groups. The phenotypic and function of lymphocytes are different between normal and inflamed appendix tissue. These results showed that the appendix tissue with special lymphocyte profile may be effective in preventing or reducing intestinal infections.