A liver-derived immunosuppressive factor is an arginase: identification and mechanism of immunosuppression.

We found a substance in culture medium of neonatal pig liver fragments, which suppresses an immune response monitored by (3)H-thymidine incorporation using phytohemagglutinin (PHA)-stimulated lymphocytes. We named it as an immunosuppressive factor (ISF). To purify ISF, ammonium sulfate fractionation, DE52, SP-Sephadex, hydroxyapatite, blue Sepharose, heparin Sepharose and Superdex gel filtration columns were used.

Rapid detection of human HLA transgenes in pigs by fluorescence in situ hybridization (FISH) for adjuvant study of human xenotransplantation.

Objectives: We have recently generated several lines of transgenic pigs for HLA-DP and -DQ to elucidate the role of HLA-II antigens in the modulation of cell-mediated rejection of xenotransplantation. Using fluorescence in situ hybridization (FISH) analysis, the aim of this study was to determine integration sites and to test zygosity of these transgenes in the piglets after cross mating.

Methods: Blood lymphocytes of transgenic pigs for HLA-DP and -DQ were collected and cultured.

The sharing of target-epitopes between human anti-ABO hemagglutinating and anti-Pig (xeno) endothelium or anti-Pig thyroglobulin antibodies.

To select congenial pairs between donor-pig and recipient-human for the future xenotransplantation, the levels of xeno-IgM natural antibodies (NAb) were analyzed in healthy subjects and hemodialysis patients by ELISA tests, which target swine-derived crude endothelial cells (P16N) or proteins (thyroglobulin; TG). The total IgM concentration was lower in hemodialysis patients than in healthy subjects, but there was no difference in IgM NAb titer between the two groups. Individuals with non-B blood types (A, O) exibited significantly higher IgM NAb titer compared with those with B blood types (B, AB).

Hepatocyte proliferation factors from neonatal pig liver: purification and characterization.

Two factors were found in the condition medium of neonatal pig liver fragments, which were capable of stimulating DNA synthesis in primary hepatocytes. They were named hepatocyte proliferation factor (HPF)-1 and HPF-2 and purified 1,025- and 2,580-fold, respectively. Both HPF-1 and HPF-2 seem to be anionic at pH 8.

Reduction of human-to-pig cellular response by alteration of porcine MHC with human HLA DPW0401 exogenes.

Background: In pig-to-human discordant xenotransplantation, the xenograft can be rejected by a formidable human xenogenic T-cell response, even if the graft has gone through hyperacute rejection or delayed xenograft rejection (acute vascular rejection). We therefore examined, in this study, whether the human-to-pig cellular response could be attenuated through the generation of a transgenic pig for human HLA II.

Methods: With the technique of microinjection, we produced the HLA DPw0401 transgenic pig.