Fresh rat corneas as well as corneas preserved in several different corneal preservation media were stained with Avidin-Biotin-peroxidase Complex method in order to evaluate major histocompatibility complex (MHC) antigen expression. In fresh corneas, class I antigen was identified in corneal epithelium, stroma and endothelium. Class II antigen was identified only in stroma. In corneas preserved in the media which contained chondroitin and dextran for 7 days, class I antigen was somewhat decreased but class II antigen was increased. In corneas preserved in the medium which contained insulin or epidermal growth factor for 7 days, class II antigens seemed to be increased compaired to the fresh cornea. Expression of MHC antigens of corneas in the medium with fetal bovine serum were similar to those of fresh corneas.
Animals ; Cornea/*metabolism ; Culture Media ; Histocompatibility Antigens Class I/*biosynthesis ; Histocompatibility Antigens Class II/*biosynthesis ; Immunoenzyme Techniques ; Major Histocompatibility Complex ; Organ Preservation/methods ; Rats ; Rats, Inbred Lew

Killer cell immunoglobulin-like receptors (KIRs) are members of the immunoglobulin superfamily expressed on natural killer (NK) cells and a subset of T cells. Given the receptor-ligand relationship between certain KIR and human leukocyte antigen (HLA) classⅠmolecules, the KIRs are involved in the regulation of NK cell activation through conveying activating or inhibitory signals, which plays an important role in immunities involved in transplantation, tumor, infection as well as autoimmune diseases. This paper has provided a review for the research on KIR gene polymorphisms and summarized the characteristics of the sequence-based typing method for KIR genes.
HLA Antigens ; genetics ; Histocompatibility Antigens Class I ; genetics ; Humans ; Killer Cells, Natural ; metabolism ; Polymorphism, Genetic ; genetics ; Receptors, KIR ; genetics

In order to construct prokaryotic expression system of MHC classI chain-related gene A (mica) and purify MICA protein, RNAs were extracted from the peripheral blood samples and mica cDNA fragments were obtained by RT-PCR method. The cDNA for mica was ligated with cloning vector by TOPO method. The recombinant cloning vector and prokaryotic expression vector pET-28a were digested by two restriction enzymes and ligated to construct pET-28a-MICA recombinant expression vector, then the pET-28a-MICA vector was transformed and expressed in E. coli BL21 DE3. The recombinant protein was purified by Ni-NTA Spin method. The results showed that the recombinant MICA protein expressed with soluble form in host with pET-28a-MICA vector after IPTG induction. The recombinant target protein was obtained by Ni-NTA spin purification. In conclusion, this study has constructed prokaryotic expression system of mica gene and has purified MICA protein which would help to explore the interaction between MICA and transplantation immunology.
Cloning, Molecular ; Escherichia coli ; metabolism ; Genetic Vectors ; Histocompatibility Antigens Class I ; genetics ; metabolism ; Humans ; Recombinant Proteins ; genetics ; metabolism

OBJECTIVETo explore the putative effects of Vitamin C (Vit C) on inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells (HPBMCs) induced by deoxynivalenol (DON) in vitro.

METHODSThe effects of Vit C on the changes of HLA-I expression of HPBMCs induced by DON in vitro were evaluated with cell culture, flow cytometry (FCM), Western blotting and immunocytochemical methods.

RESULTSFCM analysis showed that HLA-I expression of HPBMCs in DON treated cells was significantly lower than that in controls (FI 0.88 +/- 0.02 vs 1.00 +/- 0.03, P < 0.05). As compared with DON group, the HLA-I expressions of HPBMCs in the two Vit C (25 micromol/L and 100 micromol/L) pretreatment groups were all significantly increased (1.15 +/- 0.06 and 1.10 +/- 0.02 vs 0.88 +/- 0.02, P < 0.05). Exposure to different dosage of Vit C alone could dramatically increase the expression of HLA-I of HPBMCs in vitro as compared with that in the normal control (FI for 25 micromol/L and 100 micromol/L Vit C treatment group was 1.28 +/- 0.03 and 1.25 +/- 0.05 respectively, P < 0.05). Immunocytochemical results showed that the percentages of HLA-I positive expression of HPBMCs in Vit C pretreatment groups at different dosages were significantly higher than those in DON group (70.10 +/- 6.90)%, (64.50 +/- 5.50)% vs (42.20 +/- 4.30)%, P < 0.05. Western blotting confirmed the results of FCM and immunocytochemistry.

CONCLUSIONSVitamin C pretreatment at different dosages could reverse at some extent the inhibitive effects of DON on HLA-I expression of HPBMCs.

Ascorbic Acid ; pharmacology ; Cells, Cultured ; Flow Cytometry ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Monocytes ; drug effects ; metabolism ; Trichothecenes ; pharmacology

The objective of this study was to explore the effect of astragalus polysaccharide (APS) on sensitivity of leukemic cell line HL-60 to NK cell cytotoxicity and its mechanism. The cytotoxicities of NK cells against HL-60 cells were analyzed by LDH releasing assay at different effect-to-target cell ratios (E:T) before and after treated with APS. The gene expression of MHC class I chain-related (MICA) in HL-60 cells before and after APS treatment was assayed with RT-PCR. Protein expression of MICA in HL-60 cells was assayed by flow cytometry before and after treated by APS. The results showed that after treated with APS 15 mg/ml for 48 h, the cytotoxicities of NK cells against HL-60 cells enhanced at different effect-to-target (P < 0.05), and the gene and protein expressions in MICA of HL-60 cells were up-regulated (P < 0.05). It is concluded that the APS can obviously up-regulate the expression of MICA in HL-60 cells, thus enhance sensitivity of HL-60 cells to cytotoxicity of NK cells.
Astragalus Plant ; Cytotoxicity, Immunologic ; drug effects ; HL-60 Cells ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Killer Cells, Natural ; Polysaccharides ; pharmacology

OBJECTIVETo examine the expressions of HLA class I antigen and CD8 in various cervical diseases and investigate their association with cervical cancer.

METHODSThe expressions of HLA class I antigen and CD8 in cervical tissues sampled from patients with cervical cancer, cervical intraepithelial neoplasia (CIN), and chronic cervicitis were detected using SP immunohistochemistry. The association of the expressions of HLA class I antigen and CD8 with the clinicopathologic indices of the patients was analyzed.

RESULTSThe positive expression rates of HLA class I antigen in cervical cancer, CIN, and chronic cervicitis were 22.6%, 100.0%, and 100.0%, and the positive expression rates of CD8 were 22.6%, 95.5%, and 100.0%, respectively. The positive rates of HLA class I antigen and CD8 were significantly lower in patients with cervical cancer (P<0.01). Patients with stage I cervical cancer had significantly higher positive rates of HLA class I antigen and CD8 than those with stage II cervical cancer (46.7% vs 0.0%, 46.7% vs 0.0%, both P<0.01). The expressions of HLA class I antigen and CD8 decreased with the progression of the clinicopathological stages, and may even become undetectable. The expressions of HLA class I antigen and CD8 were not related to the differentiation degree of the tumor or lymph node metastasis (P>0.05). A positive correlation was found between HLA class I antigen expression and CD8 expression.

CONCLUSIONThe expressions of HLA class I antigen and CD8 are down-regulated or deleted in CIN and cervical cancer, and they may play important roles in the development and progression of CIN and cervical cancer.

Adult ; Aged ; CD8 Antigens ; immunology ; metabolism ; Cervical Intraepithelial Neoplasia ; immunology ; pathology ; Down-Regulation ; Female ; Histocompatibility Antigens Class I ; immunology ; metabolism ; Humans ; Middle Aged ; Uterine Cervical Neoplasms ; immunology ; pathology

OBJECTIVE: To investigate the mRNA and protein expression of MICA in laryngeal squamous cell carcinoma tissue and the Hep-2 cells. METHOD: Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western-blot were used to detect the expression of MICA mRNA and protein levels in the Hep-2 cells and laryngeal cancer tissues. RESULT: The MICA mRNA showed higher expression in Hep-2 cells by RT-PCR. Compared with the control, the mRNA expression of MICA was significantly enhanced in laryngeal cancer tissues (t = 11.878, P < 0.01). The intensity of MICA expression is not related to the clinical stage of cancer. MICA protein demonstrated higher level expression by Western blot. The intensity of MICA protein expression was decreased with increased clinical stage in laryngeal cancer tissues. CONCLUSION The MICA mRNA showed stronger expression in Hep-2 cells and laryngeal cancer tissues. The intensity of its expression is not related to clinical stage of cancer. The MICA protein expression was strong in Hep-2 cells. The intensity of MICA protein expression was decreased with increased clinical stage in laryngeal cancer tissues. MICA may play an important role in laryngeal carcinoma process.
Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Line, Tumor ; Head and Neck Neoplasms ; metabolism ; pathology ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; Squamous Cell Carcinoma of Head and Neck

To obtain large quantity of human leukocyte antigen F (HLA-F) and cluster of differentiation 8alpha homodimers (CD8alphaalpha) proteins and to study their relationship, HLA-F and CD8alpha genes with rare codon in Escherichia coli were cloned using an N-terminal synonymous mutation method. High-efficiency expression protein inclusion bodies were acquired. The proteins were refolded using the dilution method and purified with gel-filtration and anion exchange chromatography. The results of gel-filtration and native-PAGE indicate that HLA-F interacts with CD8alphaalpha. This interaction may affect the binding between CD8alphaalpha and other MHC molecules to regulate immune responses. These results provide a basis for further research of HLA-F.
CD8 Antigens ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Histocompatibility Antigens Class I ; biosynthesis ; genetics ; Humans ; Mutation ; Protein Interaction Domains and Motifs ; Protein Multimerization ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification

OBJECTIVETo explore the expression of MICA/B in human esophageal cancer, and to analyze its correlation with clinicopathological features.

METHODSThe expression of MICA/B in 40 cases of esophagus carcinoma and corresponding normal esophageal mucosa tissues were examined by immunohistochemistry.

RESULTSThe positive rate of expression of MICA/B protein in the esophageal carcinoma was 75.0% (30/40), and that in the corresponding normal esophageal mucosa was 0 (0/40). Up-regulation of MICA/B expression was found in the esophageal carcinomas. The expression of MICA/B was related with histological grade of the esophageal carcinoma (P = 0.012).

CONCLUSIONMICA/B protein plays an important role in the esophageal carcinogenesis, and my become a useful molecular marker for the diagnosis of esophageal carcinoma.

Adult ; Aged ; Aged, 80 and over ; Biomarkers, Tumor ; metabolism ; Esophageal Neoplasms ; diagnosis ; metabolism ; pathology ; Female ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Neoplasm Grading ; Up-Regulation

The NOD like receptors (NLRs), a class of intracellular receptors that respond to pathogen attack or cellular stress, have gained increasing attention. NLRC5, the largest member of the NLR protein family, has recently been identified as a critical regulator of immune responses. While NLRC5 is constitutively and widely expressed, it can be dramatically induced by interferons during pathogen infections. Both in vitro and in vivo studies have demonstrated that NLRC5 is a specific and master regulator of major mistocompatibility complex (MHC) class I genes as well as related genes involved in MHC class I antigen presentation. The expression of MHC class I genes is regulated by NLRC5 in coordination with the RFX components through an enhanceosome-dependent manner. And the involvement of NLRC5 in MHC class I mediated CD8+ T cell activation, proliferation and cytotoxicity is proved to be critical for host defense against intracellular bacterial infections. Nevertheless, the role of NLRC5 in innate immunity remains to be further explored. Here, we review the research advances on the structure, expression regulation and function of NLRC5.
Animals ; CD8-Positive T-Lymphocytes ; immunology ; metabolism ; Histocompatibility Antigens Class I ; genetics ; metabolism ; Humans ; Immunity, Innate ; Intracellular Signaling Peptides and Proteins ; chemistry ; genetics ; metabolism