Toshihiko Oiwa

Induction of antiidiotypic antibodies by donor-specific blood transfusions. Establishment of a human-mouse hybridoma secreting the MLR-inhibiting factor

We describe a patient transfused with 200 ml of donor fresh whole blood three times at 2-week intervals. Three weeks after the last transfusion, transplantation and splenectomy were done at the same time. Splenic cells from this DST pretreated patient were fused with murine myeloma cells (X63-Ag8, 653). With DST pretreatment, various clones were developed in vivo, and finally 69 human immunoglobulin-secreting clones were obtained. Modulation of the alloantigen-specific MLR by supernatants from 69 clones showed various degrees of suppression or augmentation. The hybridoma clone 7 and clone 2, which had been secreting IgG antibody for more than 6 months, showed some degree of suppression in the alloantigen-specific MLR (mean suppression = 63%, 46% respectively). According to the result of MLR, clone 7 antibody was directed against recipient lymphocytes and clone 2 antibody was against donor lymphocytes. Immunoprecipitation was carried out by clone 7-IgG and clone 2-IgG. Clone 7-IgG specifically precipitated 1 molecule from the recipient lymphocyte with a molecular weight of 120 KD, similar to the molecular weight range reported for T cell receptors. Clone 2-IgG precipitated a 20 KD molecule from the donor lymphocyte. The data suggest that DST induces antibodies directed against the blood donor alloantigen-specific receptors on the recipients T lymphocytes--and, at the same time, induces antibodies against donor lymphocyte antigens. These antibodies may be essential to prolongation of kidney allograft survival following DST.

Immunosuppressive mechanism of 15-deoxyspergualin on sinusoidal lining cells in swine liver transplantation: Suppression of MHC class II antigens and interleukin-1 production

To elucidate the precise mechanism of action of 15-deoxyspergualin (DSG) in swine liver transplantation, the expression of MHC class II antigens (Ia) on hepatic sinusoidal lining cells (SLC) and their production of interleukin-1 (IL-1) were examined. In our previous study, we isolated sinusoidal endothelial cells (SEC) and Kupffer cells (KC) by enzymatic digestion and centrifugal elutriation, and demonstrated that both SEC and KC present alloantigens effectively and generated IL-1 in response to allogenic or lipopolysaccharide stimulation. Animals were divided into three groups: group 1, nontransplanted normal controls (n = 3); group 2, no immunosuppressive treatment following liver transplantation (n = 5); group 3, DSG (0.8 mg/kg/day) intravenously for 7 days following liver transplantation (n = 5). At 1 week after transplantation, the three liver grafts in groups 2 and 3 were processed for the study of Ia expression and IL-1 production on SEC and KC. The expression of Ia was detected in 21.5 +/- 4.7% of SEC and 24.3 +/- 11.1% of KC in group 1. In group 3, Ia expression was suppressed compared with group 2, being 3.6 +/- 2.8% versus 22.0 +/- 2.8% for SEC (P less than 0.02) and 15.5 +/- 11.3% versus 24.3 +/- 7.1% for KC. IL-1 production by SEC and KC was respectively 11,483 +/- 3311 cpm and 9077 +/- 2161 cpm in group 1. In group 3, IL-1 production was inhibited compared with that in group 2, being 7190 +/- 883 cpm versus 19,297 +/- 5182 cpm for SEC (P less than 0.05) and 16,130 +/- 3769 cpm versus 25,857 +/- 3963 cpm for KC.(ABSTRACT TRUNCATED AT 250 WORDS)