In this study, we prepared the acellular bone matrix of the inbred-line Banna mini-pig by using tissue engineering method and evaluated its possible application in bone tissue engineering. Histological analysis, xenoantigen expression and biomechanical measurement were performed on the matrix. HE staining and scanning electron microscopy showed the cellular components were almost removed. Immunohischemical result demonstrated that the xenoantigen, alpha-gal,was also eliminated. There was no statistically significant difference between the acellular bone matrix group and control group. The acellular bone matrix can provide appropriate space structure and strength for grafts. In conclusion, our data suggest that acellular bone matrix is a new kind of ideal bone scaffold material.
Animals ; Antigens, Heterophile ; analysis ; Biomechanical Phenomena ; Bone Matrix ; immunology ; Female ; Male ; Stress, Mechanical ; Swine ; Swine, Miniature ; Tissue Engineering ; alpha-Galactosidase ; analysis

αGal, a xenotransplantations antigen (XTA), can lead to hyper acute reaction (HAR) in xenotransplantation. α-Galactosidase from B. fragilis is a novel galactosidase belong to CAZy GH110 which can clear the terminal αGal from branched and linear oligosaccharides. This study was purposed to investigate the removal effect of a novel α-galactosidase on α-Gal XTA on surface of red blood cells. The αGal XTA from the red blood cells of cattle, pig, dog and rabbit was digested by using recombinant α-galactosidase; the α-Gal antigens on surface of cells was detected by flow cytometry. The results showed that the XTA was disappeared completely or mainly. It is concluded that the novel α-galactosidase is a potential enzyme to remove the XTA on the surface of xenotransplants and can be used to overcome the HAR in xenotransplantation.
Animals ; Antigens, Heterophile ; immunology ; Cattle ; Dogs ; Epitopes ; Erythrocytes ; immunology ; Macaca mulatta ; Mice ; Mice, Inbred BALB C ; Rabbits ; Swine ; Transplantation, Heterologous ; alpha-Galactosidase ; immunology

OBJECTIVETo investigate the therapeutic effect of sequential intratumoral injection of xenogeneic antigens in immunized tumor-bearing mice.

METHODSSequential intratumoral injection of the xenoantigens was performed in immunized mice bearing S180 tumor. The tumor size changes were observed, and the tumor-infiltrating lymphocytes (TIL) including CD3+CD4+T, CD3+CD8+T, and CD3+CD4+CD25+T lymphocytes were counted with flow cytometry. The concentrations of IL-2 and TNF-alpha in the tumor was measured using ELISA.

RESULTSNo significant difference was found in the number of CD3+T lymphocytes in the TILs between different groups. After the immunotherapy, the percentages of CD3+CD4+T, CD3+CD8+T and CD3+CD4+CD25+T lymphocytes were 54%, 22% and 2.91%, respectively, with the CD4+/CD8+ ratio of 2.49, significantly different from that in the control group (P<0.05). The concentrations of IL-2 and TNF-alpha were 100.61 pg/ml and 54.114 pg/ml, respectively, significantly different from those in the control group (P<0.05).

CONCLUSIONSequential intratumoral injection of heteragenetic antigena can significantly increase the amount of effector cells and cytokines in the micro-environment of the tumor, and decrease the expression of T regulatory.

Animals ; Antigens, Heterophile ; immunology ; CD4-CD8 Ratio ; Female ; Immunotherapy ; methods ; Lymphocytes, Tumor-Infiltrating ; cytology ; Male ; Mice ; Random Allocation ; Sarcoma 180 ; immunology ; therapy ; Streptococcus ; immunology

In Sprague Dawley (SD) rats, antibodies against strains of Orinentia tsutsugamushi, Kato, Karp and Gilliam, were produced in order to investigate their longevity and cross-reactivities to their corresponding homologous and heterologous antigens. By immunofluorescence assay (IFA) of IgG and IgM, it was shown that the immunity to the homologous strains persisted at a higher level (longevity of at least 34 weeks with higher IFA titers). On the other hand, the immunity to the heterologous strains persisted at a lower level (longevity of 10 to 34 weeks with lower IFA titers). Since infection with one strain of O. tsutsugamushi does not preclude reinfection with other strains, understanding of the antigenic diversity of O. tsutsugamushi and duration of the immunity to both homologous and heterologous strain is very important in diagnosis of scrub typhus.
Animals ; Antibodies* ; Antigenic Variation ; Antigens, Heterophile ; Diagnosis ; Fluorescent Antibody Technique ; Hand ; Immunoglobulin G ; Immunoglobulin M ; Longevity* ; Orientia tsutsugamushi* ; Rats ; Rats, Sprague-Dawley* ; Scrub Typhus

This study was aimed to explore impact of removal of cell membrane G alalpha1-3Gal beta1-4Glc NAc epitopes (called alpha-Gal) and chemical modification of other xenoantigen on bovine red blood cell (bRBC) and porcine red blood cell (pRBC) antigenicity and to compare their modified erythrocytes, in order to provide basis for development of human blood substitute with rich source, high safety and efficacy. bRBC and pRBC were subjected to both enzymatic removal of membrane alpha-Gal with recombinant coffee bean alpha-galactosidase (rC alpha-GalE) and covalent attachment of benzotriazole carbonate-linked methoxypolyethylene glycol (mPEG-BTC, MW = 20 kD). The effects of treatment were measured by hemagglutination, flow cytometric assay of IgG binding and clinical cross-match testing to human sera. The results showed that although alpha-galactosidase treatment reduced hemagglutination titers to levels similar to negative control, the combination of the treatments was most effective. Clinically used cross-match tests between bRBC, pRBC and human sera demonstrated increased compatibility. Bovine RBC were more robust than pRBC, and had less xenoantigens, and had longer half life than pRBC in vivo. These characteristics suggested that bRBCs were more suitable to investigation as an alternatives to hRBC in clinical transfusion than pRBC. These data suggested that strategies to remove or mask xenoantigens on bRBC reduce antigenicity sufficiently to allow in vitro cross-match compatibility to human sera, and therefore bRBC following modification may be considered as human blood substitute.
Animals ; Antigens, Heterophile ; immunology ; Blood Substitutes ; Cattle ; Disaccharides ; immunology ; Epitopes ; immunology ; Erythrocyte Membrane ; immunology ; Erythrocyte Transfusion ; methods ; Erythrocytes ; immunology ; metabolism ; Humans ; Swine ; alpha-Galactosidase ; immunology

To explore the changes of the antigen expression and the biomechanical characteristics of blood vessel in Banna little ear pig before and after trypsin treatment, and provide data for xenotransplantation and pig vessel using for tissue engineering. Geometric morphology and microstructure of pig cartoid artery were stuided quantitatively by histologic method and computer image analysis. The relationship between pressure and diameter was observed at different period of time before and after trypsin treatment. Affinity-immunohistochemistry assay was conducted to detect the expression of xenoantigens (alpha-Gal). The results showed that alpha-Gal antigen is only expressed in vascular endothelial cellsouly. There is no significant difference in blood vessel compliance. These demonstrate that the antigenicity of pig carotid artery is significantly reduced, however, the mechanical characteristics did not change significantly. We suppose that pig vessels treated by trypsin can be used as the substrate material for vascular tissue engineering.
Animals ; Animals, Inbred Strains ; Antigens, Heterophile ; biosynthesis ; Blood Vessels ; drug effects ; physiology ; Female ; Male ; Stress, Mechanical ; Swine ; Tissue Engineering ; Trypsin ; pharmacology

OBJECTIVETo explore the strategies which reduce the amount of xenoantigen Galalpha1,3Gal.

METHODSHuman alpha-galactosidase gene and alpha1,2-fucosyltransferase gene were transferred into cultured porcine vascular endothelial cells PEDSV.15 and human alpha-galactosidase transgenic mice were produced. The Galalpha1,3Gal on the cell surface and susceptibility of cells to human antibody-mediated lysis were analyzed.

RESULTSHuman alpha-galactosidase gene alone reduced 78% of Galalpha1,3Gal on PEDSV.15 cell surface while human alpha-galactosidase combined with alpha1,2-fucosyltransferase genes removed Galalpha1,3Gal completely. Decrease of Galalpha1,3Gal could reduce susceptibility of cells to human antibody-mediated lysis, especially during co-expression of alpha-galactosidase gene and alpha1,2-fucosyltransferase gene. RT-PCR indicated positive human alpha-galactosidase gene expression in all organs of positive human alpha-galactosidase transgenic F1 mice including heart, liver, kidney, lung, and spleen, the amount of Galalpha1,3Gal antigens on which was reduced largely. 58% of spleen cells from F1 mice were destroyed by complement-mediated lysis compared with 24% of those from normal mice.

CONCLUSIONSHuman alpha-galactosidase gene and alpha1,2-fucosyltransferase gene effectively reduce the expression of Galalpha1,3Gal antigens on endothelial cell surface and confers resistance to human serum-mediated cytolysis. The expression of human alpha-galactosidase in mice can also eliminate the Galalpha1,3Gal antigens in most tissues and decrease the susceptibility of spleen cells to human serum-mediated cytolysis.

Animals ; Antigens, Heterophile ; metabolism ; Cell Death ; Cells, Cultured ; Disaccharides ; metabolism ; Endothelial Cells ; metabolism ; Fucosyltransferases ; genetics ; metabolism ; Graft Rejection ; genetics ; Humans ; Mice ; Mice, Transgenic ; Spleen ; cytology ; Swine ; Transfection ; alpha-Galactosidase ; genetics ; metabolism

The understanding of main mechanisms that determine the ability of immune privilege related to Sertoli cells (SCs) will provide clues for promoting a local tolerogenic environment. In this study, we evaluated the property of humoral and cellular immune response modulation provided by porcine SCs. Porcine SCs were resistant to human antibody and complement-mediated formation of the membrane attack complex (38.41+/-2.77% vs. 55.02+/-5.44%, p=0.027) and cell lysis (42.95+/-1.75% vs. 87.99 +/-2.25%, p<0.001) compared to immortalized aortic endothelial cells, suggesting that porcine SCs are able to escape cellular lysis associated with complement activation by producing one or more immunoprotective factors that may be capable of inhibiting membrane attack complex formation. On the other hand, porcine SCs and their culture supernatant suppressed the up-regulation of CD40 expression (p<0.05) on DCs in the presence of LPS stimulation. These novel findings, as we know, suggest that immune modulatory effects of porcine SCs in the presence of other antigen can be obtained from the first step of antigen presentation. These might open optimistic perspectives for the use of porcine SCs in tolerance induction eliminating the need for chronic immunosuppressive drugs.
Animals ; Antibodies, Heterophile/immunology ; Antibody Formation/*immunology ; Antigens, CD40/immunology ; Aorta/cytology ; Cell Line, Transformed ; Cell Survival/immunology ; Complement Membrane Attack Complex/immunology ; Complement System Proteins/immunology ; Dendritic Cells/cytology/immunology ; Endothelial Cells/cytology/immunology ; Epitopes/immunology ; Humans ; Immune Tolerance/*immunology ; Immunity, Cellular/*immunology ; Male ; Mice ; Mice, Inbred C57BL ; Sertoli Cells/cytology/*immunology ; Swine ; *Tissue Engineering ; Transplantation, Heterologous