Influence of a DLE-extracted lymphocytic suppressor factor on CsA-induced immunosuppression.

From dialyzable leucocyte extracts (DLE) we have purified a hydrophilic low-mol. wt. factor (about 1 kDa) which we have named lymphocytic suppressor factor (LSF) as it is able to suppress antigen- and mitogen-induced lymphocyte transformation and to prolong allograft survival in C57b/6N mice (H-2b) transplanted with fully mismatched skin from C3H/HeN mice (H-2k).

Bovine seminal plasma contains factors that enhance lymphocyte transformation in vitro.

The important immunosuppressive properties of seminal plasma have significant functions in the processes of reproduction. They mask the presence of an immunostimulating activity. From bovine seminal plasma two active factors have been isolated and characterized with marked enhancing activity for in vitro PHA-dependent lymphocyte transformation.

Inhibition of in vitro adherence of antibody-coated red cells to monocytes by the dialyzable leukocyte extract.

The red cell-monocyte assay (RMA), which has been used to evaluate the clinical significance of red cell (RBC) antibodies, was employed to test the effect of the dialyzable leukocyte extract (DLE) on in vitro adherence to monocytes of human RBCs coated with alloantibodies or autoantibodies. The total association index (TAI) of the RMA, expressing the number of RBCs adhering to or phagocytosed by 100 monocytes, indicated a potent inhibitory activity of DLE in the test system. TAI values of 100.

Purification of immunomodulatory factors in human peripheral blood leukocytes.

Procedure is described for purifying low-molecular-weight factors with antigen-aspecific properties from a dialysate of human leukocyte extract. It includes gel chromatography on Sephadex G-25 and G-15, ion-exchange chromatography, reversed-phase high-performance liquid chromatography (HPLC) on a C18 hydrophobic column and gel permeation HPLC. The immunosuppressive factor (mol.

Functional C8 associated with human platelets.

Haemolytic assay for C8 revealed its association in functionally active form with washed human platelets. Platelet-bound C8 haemolytic activity was inhibited by F(ab')2 anti-C8 and was undetectable in the platelet suspension obtained from three C8 deficient patients. Incubation of platelets from C8 deficient individuals in normal plasma did not restore C8 haemolytic activity, indicating that platelets do not absorb C8 from plasma in vitro during platelet preparation.

Blood transfusion and kidney transplantation: effect of small doses of blood on kidney graft function and survival.

A controlled clinical trial was started to evaluate whether small doses of blood given pretransplant determine a transfusion effect while reducing the risk of antibody production. For this purpose, 65 consecutive never transfused patients suffering from end-stage renal failure were assigned to one of two groups: the first group was transfused with 1 unit of packed red cells (containing a mean of 2350 x 10(6) leukocytes, 900 x 10(6) mononuclear cells) 3 times at 15-day intervals. The second group received one transfusion of about 30 ml of blood adjusted to contain 100 x 10(6) mononuclear cells.

Study on the turnover of the receptor for the third component of complement on human lymphoid cells.

The in vitro turnover of the receptor for the third component of complement (C3) was studied in normal peripheral blood lymphocytes (PBL) and in lymphoblastoid cells from established cell cultures of both "normal" and "malignant" origin. The turnover was evaluated by studying i) the disappearance rate of the C3-receptor in cells in which the protein synthesis was blocked by cycloheximide and puromycin, ii) the reexpression rate of the C3-receptor after treatment of the cells with either rabbit antiserum against B lymphocytes or mouse C activated through the alternative pathway by inulin. The results show that the C3-receptor of all the lymphoid cells has roughly a half-life of about 3 to 4 hr.

The cadaver kidney transplantation programme of Milano. Immunological report.

A retrospective investigation was carried out to evaluate the infuence of HLA (A, B) matching, blood transfusions, and preexistence of lymphocytotoxic antibodies on the outcome of the cadaver kidney graft: only non-NIH standard antibodies were considered, since patients with NIH standard antibodies do not undergo transplantation in the programme of Milano. It was found that (1) about one-half the patients with transplants had antibodies in their pretransplant serum. The preexistence of antibodies directed against B lymphocytes had an unfavourable effect on the graft survival; (2) the graft did particularly well in the nonimmunized patients who had been previously transfused; the graft survival was about 80% at 3 years in these patients; and (3) the HLA (A, B) match influenced the graft survival only in patients with antibodies.