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Cell-mediated and humoral immune responses against antigens associated with primate C-type oncoviruses were evaluated in humans by microcytotoxicity and radioimmunoprecipitation assays. Five of six women tested sequentially during pregnancy developed selective cell-mediated reactivity against baboon endogenous virus (BEV)--infected human fibroblasts. Responsiveness peaked during the second and third trimesters and corresponded temporally with elevated antibody levels to BEV antigens. Similar cell-mediated reactivity was not observed in nonpregnant individuals. Selective cell-mediated reactivity directed against cells infected with the simian sarcoma virus-simian sarcoma associated virus complex (SSV--SSAV) was observed in four of 20 healthy adults (three of 14 nonpregnant, one of six pregnant). These observations suggest that cell-mediated reactivity against primate C-type oncoviruses is occasionally detected in healthy nonpregnant adults, but that during pregnancy both cell-mediated and humoral reactivity against BEV may become selectively expressed.

The phenotype and function of T lymphocyte cell lines established in vitro from kidney biopsies at the time of acute cellular rejection were studied using a nonhuman primate renal allograft model. Our objectives were to investigate the function and surface phenotype of cells that infiltrate renal allografts in animals that were untreated, that were given subtherapeutic cyclosporin, or that developed rejection after treatment with monoclonal antibodies to IL-2R B chain (CD25), immune cell adhesion molecule-1 (ICAM-1), or CD8. Lines from allograft biopsies and peripheral blood were expanded in vitro using solely human recombinant IL-2 and analyzed after 6-20 days in culture. We found that the large majority of cells cultured from cynomolgus allografts at the time of acute rejection or, when possible, assayed directly without culture, were CD3+4-8+ T lymphoblasts that possessed donor-specific cytolytic function and an NK-line, cytotoxic activity. In contrast, it was rarely possible to establish T cell lines exhibiting donor-specific cytotoxic activity from the blood except in the absence of immunosuppression or during CsA taper. A stable number of graft-derived CD4+8- cells was only observed in an unsuppressed animal 2 days after transplantation in the absence of manifest signs of rejection. Taken together, the above data indicate that similar T lymphocyte populations associated with allograft rejection are present in acutely rejecting allografts after the various types of immunosuppressive therapy. Since the infiltrating cells were similar to those obtained prior to therapy, recurrent rejection most likely represents cells that have escaped elimination. The T cells derived from monkey grafts differ from those from human renal allografts by the decreased frequency of CD4+ cells. Whether this difference is species-related or therapy-related is not known.

The authors describe two HLA identical sibling pairs with panic disorder. To their knowledge, this is the first report of histocompatibility testing in patients with anxiety disorders.

Characterization of the host immune response to human immunodeficiency virus type 1 (HIV-1) is critical to the rational design of an effective AIDS vaccine. In this study, cytotoxic T lymphocytes (CTL) specific for HIV-1 reverse transcriptase (RNA-dependent DNA polymerase) were found in blood samples from HIV-1-infected individuals. CTL targets were prepared by immortalizing B cells from ten seropositive and six seronegative individuals, and then infecting these cells with recombinant vaccinia viruses containing HIV-1 genes. CTL directed against autologous B lymphoblasts expressing HIV-1 reverse transcriptase were detected in fresh blood samples from eight HIV-1 seropositive subjects, but in no seronegative controls. The effector cells were identified as major histocompatibility complex-restricted CD3+CD8+ lymphocytes. Because the HIV-1 pol gene is highly conserved among different isolates and generates both humoral and cellular immune responses, it bears consideration for inclusion in a candidate AIDS vaccine.

The relationship between transfusion of different preparations of blood, sensitization to HLA antigens and survival of subsequent kidney transplants was investigated in 90 consecutive recipients. HLA lymphocytotoxins in transplant candidates precluded or greatly delayed receipt of an allograft (p less than 0.0005). Furthermore, only 17% of such sensitized recipients had functioning grafts one year after transplantation compared to 57% survival for nonsensitized recipients (p less than .02). A small number of nonsensitized patients who were never transfused had surprisingly poor one year graft survival (25%). If frozen blood is used for transfusion rather than whole/packed RBC, the incidence of patient sensitization can be markedly reduced without subsequent compromise in transplant survival (51%). It is concluded that as a consequence of avoiding HLA sensitization by transfusion of frozen blood (processed by agglomeration), the period of hemodialysis required for potential graft recipients will be shortened and an increased proportion of potential recipients will be successfully treated by transplantation.

The human TH lymphocyte population has been established to express a differentiation antigen (T4) which appears to function in cellular collaboration and T cell recognition of Class II MHC alloantigens. Because we observed altered immunofluorescence staining of the TH cells of some individuals using the OKT4 mAb, a systematic investigation on both the epitopic structure of the T4 glycoprotein molecule and possible polymorphism of these epitopes was undertaken. From competitive blocking assays using eight murine anti-T4 mAbs coupled with quantitative flow cytometry, at least five and possibly seven different epitopes can be recognized on the T4 molecule. Population studies showed some individuals had a reduced phenotypic expression of the OKT4 reactive determinant to one-half that of normal and others completely lacked this epitope. The OKT4 reactive epitope variations are common but have so far been racially restricted to American Blacks and do not appear related to the stage of TH cell differentiation, any identifiable immune abnormality in vitro, or a definable disease process. The OKT4 epitope cannot be unmasked by neuraminidase treatment or T cell stimulation with lectins, soluble antigens, or allogeneic lymphocytes. Coupled with a family study, the alterations in OKT4 phenotype are best explained by autosomal, codominant expression of the T4 gene product. The significance of this polymorphism on TH cell function remains unclear.

To evaluate in situ lymphocyte responses in cell-mediated immune tissue injury, we have developed an approach for propagation of human allospecific T lymphocytes directly from tissue biopsies. We have utilized renal allograft tissue obtained from eight patients undergoing cellular rejection. Needle biopsy tissue was cultured in medium containing interleukin 2 (IL 2), including recombinant-DNA-produced IL 2. In each case, lymphoblasts migrated out of the tissue and increased in numbers, especially adjacent to the tissue. In two cases in which there was no cellular infiltrate present in the biopsy, no lymphocytes proliferated in vitro. Instead, fibroblasts eventually filled the wells from these allograft biopsies. The continued presence of the allograft tissue enhanced the viability and growth of the lymphoblasts in cultures from rejecting allografts. The isolated lymphoblasts had surface markers of mature OKT3+ lymphocytes of either OKT4+ or OKT8+ subsets. OKT8+ cells predominated. There was variability (41 to 97%) in the percentage of T lymphoblasts that bore surface HLA-DR antigens. In assays of lymphoblasts obtained from eight separate renal allografts, there was donor-specific cytotoxicity, and in all but two of the cases there was donor-induced proliferation. The specificity of the cytotoxic reaction was tested by using 51Cr-labeled, PHA-stimulated target cells prepared from a panel of HLA-typed donors. Proliferation was tested after 48 hr in the presence of mitomycin C-treated peripheral blood mononuclear cells as stimulator cells by using only 10(4) responder T lymphoblasts. Of particular note was that the cytotoxicity of the isolated lymphoblasts showed specificity against both "private" HLA class I alloantigens (of the allograft donor) as well as "public" cross-reacting epitopes. This method permits the propagation and functional characterization of in vivo-activated T lymphoblasts that are obtained from the actual sites of immune-mediated injury. Preliminary studies of other tissues with diverse inflammatory processes indicate the possible widespread applicability of obtaining in vivo-activated lymphocytes.

The frequency, timing, and specificity of the humoral antibody response to a murine monoclonal antibody (OKT3, IgG2a) were measured in 21 consecutive renal allograft recipients. These patients received i.v. OKT3, 1-5 mg/day for 10-20 days as treatment for acute graft rejection. Maintenance immunosuppression consisted of azathioprine and corticosteroids. Using three different assays, an antibody response was detected in 75% of the 20 patients with adequate samples. The ELISA assay of the overall IgM and IgG reactivity to OKT3 revealed that IgM anti-OKT3 appeared in 65% and IgG anti-OKT3 in 50% of the patients, reaching a peak 20-33 days after the last dose of OKT3. The IgM preceeded the IgG in most cases (P less than 0.02) and in 8 cases was detected during therapy. One patient had high levels of IgM anti-OKT3 before therapy, yet responded normally to OKT3. Interference with the therapeutic effectiveness was evident in one patient who developed IgG antibodies during therapy. His serum blocked the binding of F-OKT3 to normal lymphocytes in the presence of normal BALB/c serum. The blocking assay, done by flow cytometry, measured anti-idiotypic (Id) reactivity since the sera did not affect the binding of OKT8 (another IgG2a) or anti-Leu4 (another anti-T3), and the blocking activity remained after affinity absorption with normal mouse IgG. Using this assay, 60% of the patients made an anti-Id response. One made only anti-Id, and several had anti-Id at times when other reactivities were undetectable. Antibodies to non-idiotypic, presumably isotypic, determinants represented on OKT8 occurred in only 44%, while other reactivity (OKT4; IgG2bK) was less common (12%) and weaker. While no adverse allergic reactions occurred in this group of patients, the anti-Id antibodies, which are a prominent feature of the immune response to this and probably other monoclonal antibodies, can block their therapeutic effectiveness and can arise despite intense immunosuppression. This response may require the use of different idiotypes for prolonged or repeated courses of therapy and may be the major obstacle to the use of human monoclonal antibodies.

Shed/soluble interleukin 2 receptor (IL2R) was measured by an enzyme-linked immunosorbent assay (ELISA) in serial samples of plasma from 32 patients with renal allografts. Patients on chronic dialysis (pretransplant) had elevated IL2R levels which fell toward normal after transplantation. Patients with acute rejection and viral infection had significantly higher levels of plasma IL2R than did patients with stable renal function or with cyclosporine nephrotoxicity (all P less than 0.005). Acute renal failure from other causes (renal artery stenosis, hemolytic-uremic syndrome) did not have a comparable rise in IL2R. The assay of shed/soluble IL2R may have diagnostic value in the clinical management of allograft recipients, a possibility that deserves further clinical evaluation.

A quantitative micro-complement fixation test capable of detecting nanogram quantities of antigen is described. The test is simple to perform and is highly reproducible. Typical results from three antigen-antibody systems are given.