OBJECTIVETo observe the immune reaction in the mixed culture of host lymphocytes with allogenic and host endothelial cells.

METHODSThe host epithelial cells and lymphocytes from burn patients and allogenic epithelial cells were mix-cultured in different ratios, so as to simulate the local immune micro-environment of host skin island in intermingled skin grafting. In addition, the cells from normal human subjects were also mix-cultured as control. The lymphocyte cpm values were detected by (3)H-TdR and HLA molecules and T cell subgroup were determined by immunohistological technique.

RESULTS(1) The lymphocyte proliferation reaction could be effectively inhibited by the epithelial cells from burn patients but not from normal control. (2) The inhibition of host lymphocyte proliferation could not be mediated by the HLA-DQ molecules of epithelium from burn patients. (3) The positive expression rate of HLA-DR of epithelia from burn patients was evidently higher that that from normal control (P < 0.05), (4) The CD8 expression of lymphocyte in burn patients was significantly higher than that in normal control (P < 0.01), while the CD4 expression in burn patients was lower than that in normal control (P < 0.01). But there was no obvious difference of the CD3 expression between patients and normal subjects (P > 0.05).

CONCLUSIONThe lymphocyte proliferation reaction could be obviously inhibited by the host epithelium, which might be related to the specific immune state of the host lymphocytes and epithelium of burn patients.

Cell Communication ; immunology ; physiology ; Cell Culture Techniques ; Cell Division ; Epithelial Cells ; immunology ; physiology ; Humans ; Lymphocytes ; immunology ; physiology ; Skin Transplantation ; immunology

Objective:To investigate T cell epitope spectrum of alpha fetoprotein (AFP) restricted by 13 dominant human leukocyte antigen A (HLA-A) molecules in Chinese population.Methods:AFP T cell epitope candidates presented by 13 HLA-A molecules were in silico predicted using multiple epitope prediction algorithms. Then, the candidate epitope peptides were co-cultured in vitro with fresh peripheral blood mononuclear cells (PBMCs) from hepatocellular carcinoma (HCC) patients, followed by intracellular cytokine staining (ICS) and flow cytometry to verify the immunogenicity of the candidate epitope peptides. Peptide competition binding assay of HLA-A molecules were performed using 12 HMy2.CIR cell lines expressing the indicated HLA-A molecules to analyze the affinity and cross-restriction of candidate epitope peptides with HLA-A molecules. Results:PBMCs from 67 AFP + HCC patients were co-cultured in vitro with 42 candidate T cell epitope peptides, and the result showed that 20 epitope peptides stimulated CD8 + T cell responses (named as positive epitope peptides). Peptide competitive binding assay revealed 22 candidate epitope peptides with high affinity, 13 with inter affinity, six with low affinity, and 10 without affinity with indicated HLA-A molecules, respectively. The 20 positive epitope peptides presented high or inter affinity with corresponding HLA-A molecules and most of them displayed cross-binding properties with several HLA-A molecules. Conclusions:Twenty AFP-specific CD8 + T cell epitope peptides restricted by the predominant HLA-A molecules in Chinese population are obtained by the HCC patients-derived T-cell functional experiments, and the cross-binding ability of these epitope peptides to the corresponding HLA-A molecules is preliminary identified. These results provide systematic and fundamental data for the design of AFP-specific T cell detection systems and T cell epitope-based vaccines universal for the Chinese population.