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R G Gill

Publications and source records attributed to R G Gill.

65 records · Page 4Linked to original sources
PubMed1987

Autoimmune diabetes in NOD mouse is L3T4 T-lymphocyte dependent.

Cultured BALB/c islets fail to function when transplanted into diabetic nonobese diabetic (NOD) mice; such grafted tissue is rapidly destroyed by disease recurrence. The cellular requirements for this graft damage are unclear. This study was designed to investigate the role of the L3T4+ T-lymphocyte subset in disease recurrence in the NOD mouse. L3T4+ T-lymphocytes were depleted by the in vivo administration of the L3T4-specific monoclonal antibody GK1.5. This treatment reduced the level of L3T4+ T-lymphocytes from an initial 43% of the peripheral blood lymphocytes to less than 4%. L3T4 levels remained at this low level for approximately 2 wk after withdrawal of GK1.5 treatment, after which the L3T4 levels slowly began to increase in the periphery. Grafting of cultured BALB/c islet tissue into GK1.5-treated diabetic NOD mice resulted in a rapid return to normoglycemia that persisted for 2-4 wk. The gradual return to the hyperglycemic condition roughly correlated with the reappearance of L3T4+ T-lymphocytes in the peripheral circulation. From these findings we conclude that the disease process in the NOD mouse is L3T4 T-lymphocyte dependent.

Animals↗
PubMed1986

Prevention of rejection by treatment of the graft: an overview.

Two signals are required for T cell activation, and because of this transplantation antigen, of itself, is not the major barrier to grafting. The major stimulus for the rejection response come from active antigen presentation by donor APC's. It is possible to reduce allograft immunogenicity by removal of these cells from the graft prior to transplantation. This procedure has been shown to be effective in the case of thyroid, parathyroid, and islet cell transplantation in animals and in the case of parathyroid grafting in man. The cultured graft is in a metastable state in the immediate post-transplantation phase; such grafts are rejected by either active or passive immunization of the host animal. With the passage of time the metastable graft moves into a stable relationship with the host. This change is the result of tolerance induction in the adult animal. The fact that allografting can be carried out without a requirement for recipient immunosuppression suggests that the helper pathway involving processing of graft antigen and presentation on host APC's, is relatively inefficient in vivo. Experimentally, lymphokine provided by T cell triggering in the region of the metastable graft does not lead to the generation of systemic immunity, suggesting that there are much more stringent requirements for the expression of T helper function in vivo than in vitro.

Animals↗
PubMed1984

The use of Lassa fever convalescent plasma in Nigeria.

Lassa fever convalescent plasma (LFCP) has been administered to 27 patients in hospitals at Jos and Vom, Nigeria. Among serologically or virologically confirmed cases of Lassa fever (LF) given plasma on or before the 10th day, all eight survived, as did two of three possible LF cases. Of eight patients given LFCP after the 10th day, five died, as did all three possible LF cases. LFCP was also administered to five patients subsequently shown not to have LF, and to a suspected case contact; all survived without complications of therapy. There were 15 cases of LF during this time who did not receive plasma; 11 survived. Most cases of LF who received plasma and survived showed a rapid response to therapy, in contrast with the gradual recovery in those who did not receive LFCP.

Adolescent↗
PubMedDate not supplied

Immunobiology of cellular transplantation.

The goal of cellular transplantation is to allow long-term function of the grafted cells using minimal host immunosuppression. To this end, the major strategies to implant cells and tissues are through: (i) the pretreatment of the graft to reduce tissue immunogenicity; (ii) the application of immunoisolation technologies to prevent host sensitization to implanted cells; and (iii) the induction of immunological tolerance to the donor tissues. Further, a major dilemma facing clinical tissue grafting is the shortage of donor tissue for transplantation. This problem requires the consideration of tissues from other species (xenografts) as a potential source of donor material. In light of these issues, the focus of this discussion is on the T cell-dependent response to allogeneic and xenogeneic transplants and the implications of this reactivity on the field of cellular replacement therapy.

Animals↗