Altered nucleic acid contents of mononuclear cells in blood of renal allograft recipients

The DNA and RNA contents of blood mononuclear cell populations of 29 cadaver renal allograft recipients and 49 blood donors (controls) were estimated by acridine orange flow cytometry (AO FCM) to assess their cell cycle status. All patients received azathioprine and prednisone for immunosuppression. The patients represented three clinical categories: clinically stable patients, those with acute rejections (clinically overt or impending), and those with infections. Three cell cycle compartments were analyzed for percentage (%) and RNA content (R) of cells: G0/1, consisting of all cells with diploid DNA content; 2 S.D., consisting of cells with diploid DNA content and RNA content 2 standard deviations above the mean RNA content of controls; and SG2M, consisting of cells with a DNA content higher than that of G0/1 cells. The relative coefficient of variation (rCV) of the DNA distribution of G0/1 cells was also determined. In such cell cycle evaluations, the means of rCV and SG2M% of stable recipients were significantly different from those of blood donors. Multivariate analysis of the variables of the three categories of patients resulted in the tentative formulation of two simple logistic equations: one that differentiates stable patients from those with impending or overt rejections based on 2SD% and another one that distinguishes infected patients from those with impending or overt rejections based on SG2M% and RG0/1.

In vivo effects of high-dose steroids on nucleic acid content of immunocompetent cells of renal allograft recipients

High-dose steroids administered to renal allograft recipients for treatment of acute graft rejection episodes may affect cell cycle progression of peripheral blood mononuclear (PBM) cells. DNA synthesis and cellular DNA and RNA contents of PBM cells were measured in 8 patients during clinically stable periods, and in another 10 patients both during acute rejection episodes and during 7 days of administration of high-dose steroids. Improved renal function documented successful reversal of the rejection episodes in the 10 patients. Compared with the stable patients, the rejecting patients had higher numbers of cells undergoing clonal expansion--namely, higher proportions of G1-cells and of proliferating, or S, G2, and M (SG2M) cells. Steroid treatment had no acute effects on proportions of G1 or SG2M cells in vivo or on incorporation of 3H thymidine by PBM cells in vitro. However, cells in the prereplicative compartment of the cell cycle (G0/1 cells) had significantly lower RNA content within 7 days of treatment with high doses of steroids. The results suggest that steroids do not acutely influence the posttranscriptional synthesis and the contents of nucleic acids of cells undergoing clonal expansion in vivo. The prereplicative phase of allogeneically stimulated PBM cells of renal allograft recipients may therefore be the cell cycle phase most sensitive to steroids in vivo.

Cyclosporine-induced remission of relapsing nephrotic syndrome in children

We treated 20 steroid-resistant or steroid-dependent nephrotic patients with oral cyclosporin for 8 weeks; they had been treated previously with cyclophosphamide or chlorambucil. Cyclosporine was started at 7 mg/kg/d and titrated to maintain a serum level of 100 to 200 ng/mL. Of 20 patients, 14 had a complete remission and the remaining six had a reduction in their proteinuria. By life table analysis, 40% of the responders show a sustained remission of up to a year. Pretherapy levels of interleukin 2, measured in 10 patients, were normal or supranormal in eight, six of whom were treatment responders; two patients with low levels of interleukin 2 were both nonresponders. Cyclosporine can be used to induce a remission in relapsing nephrotic patients, and short-term cyclosporine therapy does not produce nephrotoxic effects.

Adoptive immunotherapy for stage IV renal cell carcinoma: a novel protocol utilizing periodate and interleukin-2-activated autologous leukocytes and continuous infusions of low-dose interleukin-2

In a pilot study involving 13 patients with advanced stage IV renal cell carcinoma, anti-tumor effects and toxicity of a novel form of adoptive immunotherapy were determined. The protocol utilizes infusions of autologous mononuclear leukocytes treated with the oxidizing mitogen sodium periodate (IO4-) and cultured in medium containing human recombinant interleukin-2 (IL-2), and continuous infusions of low-dose IL-2 (mean +/- SD dose = 39.5 +/- 8.6 X 10(3) U/kg/24 hours). Leukocytes (5 to 10 X 10(9] were removed by leukapheresis three times per week, mononuclear cells were separated, activated with IO4- and cultured in medium containing IL-2 (500 U/ml) for 48 to 72 hours. The cells were re-infused following the next leukapheresis procedure. IL-2 was administered five days per week. Treatment was continued for two three-week cycles. An increase in peripheral blood mononuclear cells bearing the natural killer cell (NK) surface marker, Leu 11, an increase in NK- and antibody-dependent cell-mediated cytotoxicity, and a slight increase in spontaneous cytotoxicity for non-NK targets were noted. Regressions (more than 50 percent decrease in tumor mass) of pulmonary, liver, bone, or soft tissue metastases were induced in six patients. Severe fluid retention did not develop in any patient and no patient required treatment in the intensive care unit. Five of the patients who showed a response have experienced a relapse at 5.2 +/- 1.0 (mean +/- SD) months. These observations indicate that IO4-/IL-2-activated killer cells plus continuous infusions of low-dose IL-2 can result in regression of metastatic renal cell carcinoma.

Inhibitory activity of cyclosporine is dependent on the activating signal(s) provided to T cells

The effects of cyclosporine on T cell activation induced by monoclonal anti-CD3 antibodies, 12-O-tetradecanoyl phorbol-13-myristate acetate (TPA), or human recombinant interleukin 2 (IL-2) were investigated. Cyclosporine inhibited anti-CD3-mediated expression of IL-2 receptors and IL-2 factor production by peripheral blood mononuclear cells (PBM). Cyclosporine did not inhibit when TPA rather than anti-CD3 was used to activate the PBM. Effects of cyclosporine on the activation of memory T cells were also dependent on the stimulus used to activate memory T cells. Cyclosporine inhibited alloantigen associated memory T cell activation, but not when IL-2 provided the necessary triggering signal to memory T cells. IL-2-mediated memory T cell activation was inhibitable with monoclonal antibodies directed at the IL-2 receptor or at the IL-2 factor. Collectively, these findings indicate that the inhibitory activity of cyclosporine is dependent on the activating signals provided to T cells. Moreover, antibodies directed at the IL-2 system together with cyclosporine might prove to be more potent immunosuppressants than either agent alone.

Effect of immunosuppressants on OKT3 associated T cell activation: clinical implications

The monoclonal antibody directed at the T cell differentiation antigen T3 (CD3, T.gp 20-25) appears to be superior to conventional high-dose steroids in the treatment of rejection in cadaveric renal graft recipients. Re-rejection episodes and other adverse reactions, probably secondary to T cell activating potential of anti-T3, continue to be clinical problems with anti-T3 therapy. We therefore examined the relative efficacy of cyclosporin A (CSA), methylprednisolone (MP), or 6-mercaptopurine (6-MP), at concentrations that are readily accomplished in clinical practice, on the activation of T cells by anti-T3. CSA or MP mediated marked and 6-MP mediated modest inhibition of anti-T3 induced proliferation of alloimmune memory T cells. CSA- or MP-inhibited anti-T3 elicited specific secondary cytolytic activity and natural killer (NK) cell activity, and 6-MP failed to prevent the augmentation of NK cell activity mediated by anti-T3. The immunosuppressants also exhibited differential effects on anti-T3-associated lymphokine production by peripheral blood mononuclear cells. Interleukin 2 production was completely inhibited by CSA, modestly inhibited by MP and not inhibited by 6-MP. Interferon gamma production was completely inhibited by CSA or MP and not inhibited by 6-MP. Our findings, in addition to providing a plausible immunological basis for some of the complications of anti-T3 therapy, provide experimental support for therapeutic strategies that include the use of CSA and/or MP along with anti-T3.

Optimization of donor specific blood transfusion in kidney transplantation

1. One hundred milliliters of stored whole blood DST, three times at weekly intervals is a practical, less immunizing and effective approach to enhance graft survival in recipients of a living-related donor kidney. 2. This protocol could also be used in sibling donor/recipient pairs who do not share a haplotype as well as in those who share two haplotypes to enhance graft survival. 3. The use of a short course of Cs (6 mg/kg/d for three weeks) along with DST appears to reduce the sensitization rate even lower. The dose of Cs used in this study produced no clinically significant adverse reactions, whereas Aza (1 mg/kg/d) often produces leukopenia. 4. DST produces significantly suppressed donor specific MLC responses in the early post-DST period; however, it increases the response at a later time. DST modulates immune responses in such a way that secondary responses upon grafting are more readily reversible by immunosuppressive agents.

Anti-tumor properties of lymphocytes activated by the oxidizing mitogens

Human peripheral blood mononuclear cells when activated with the oxidizing mitogens, neuraminidase/galactose oxidase or sodium periodate, express cytolytic activity for freshly isolated tumor cells and for a variety of cell lines, including NK-resistant solid tumor lines. Normal lymphoid cells are not targets for cytotoxicity and do not inhibit lysis of susceptible targets mediated by the oxidizing mitogen-activated mononuclear cells. The cytotoxic response is rapidly generated and reaches peak levels at 48 hr. The oxidizing mitogens induce expression of IL 2 receptors on peripheral blood mononuclear cells. Combined treatment of cells with IL 2 and the oxidizing mitogens results in a marked enhancement of cytotoxicity. Enhancement is achieved at levels of IL 2 that alone result in minimal generation of cytotoxic cells. Growth of a human renal cancer cell line in nude mice was inhibited when the renal cancer cells were injected together with oxidizing mitogen-activated human mononuclear cells. These studies indicate that oxidizing mitogen-activated cells provide a potentially valuable source of material for the adoptive immunotherapy of tumors.

Anti-tumor properties of lymphocytes activated by the oxidizing mitogens

Human peripheral blood mononuclear cells when activated with the oxidizing mitogens, neuraminidase/galactose oxidase or sodium periodate, express cytolytic activity for freshly isolated tumor cells and for a variety of cell lines, including NK-resistant solid tumor lines. Normal lymphoid cells are not targets for cytotoxicity and do not inhibit lysis of susceptible targets mediated by the oxidizing mitogen-activated mononuclear cells. The cytotoxic response is rapidly generated and reaches peak levels at 48 hr. The oxidizing mitogens induce expression of IL 2 receptors on peripheral blood mononuclear cells. Combined treatment of cells with IL 2 and the oxidizing mitogens results in a marked enhancement of cytotoxicity. Enhancement is achieved at levels of IL 2 that alone result in minimal generation of cytotoxic cells. Growth of a human renal cancer cell line in nude mice was inhibited when the renal cancer cells were injected together with oxidizing mitogen-activated human mononuclear cells. These studies indicate that oxidizing mitogen-activated cells provide a potentially valuable source of material for the adoptive immunotherapy of tumors.

Impact of renal donation. Long-term clinical and biochemical follow-up of living donors in a single center

Forty-six renal donors who responded to a questionnaire and two additional donors with nephrotic syndrome and renal insufficiency were studied. The mean age was 46 +/- 2.0 years (mean +/- SE). Duration of follow-up was 6 +/- 0.5 years. Serum creatinine levels increased from 1.0 +/- 0.03 mg/dl before donation to 1.2 +/- 0.04 mg/dl at follow-up. The incidence of proteinuria (more than 150 mg over 24 hours) was 39 percent. The serum creatinine level was 1.0 +/- 0.08 mg/dl and 1.2 +/- 0.06 mg/dl in the proteinuric and nonproteinuric groups, respectively. The incidence of hypertension was 31 percent with a serum creatinine level of 1.1 +/- 0.11 mg/dl and 1.2 +/- 0.07 mg/dl in the hypertensive and normotensive groups, respectively. One patient with nephrotic syndrome had proliferative glomerulonephritis. It is concluded that renal donation is associated with a minimal but statistically significant increment in serum creatinine levels. The incidence of mild hypertension and proteinuria is increased, but impact on renal function is minimal as assessed by serum creatinine determination.

Human B lymphoblastoid cell lines provide an interleukin 1-like signal for mitogen-treated T lymphocytes via direct cell contact

The B lymphoblastoid cell lines (B-LCL) 8392, SB, 1788, and Daudi provide accessory cell activity for mitogen-treated T cells, whereas the T lines MOLT-4, 8402, CEM, and HSB do not provide this function. Direct cell contact is required for the accessory cell activity, and active lymphocyte growth factors could not be detected in the supernatants of the B-LCL. The B-LCL also present alloantigens to responding T cells, and this response is independent of additional accessory cells. The target for the B-LCL is the responding T cell itself, rather than a minor contaminating population of endogenous accessory cells. This conclusion is based on the finding that, under culture conditions in which T cells do not proliferate in response to PHA, accessory cell activity of the B-LCL is maintained. Paraformaldehyde- or glutaraldehyde-treated B-LCL retain their accessory cell activity at levels of these agents that completely eliminate metabolic activity of the B-LCL, as determined by incorporation of leucine, thymidine, and uridine into macromolecules. This treatment eliminates alloantigen presentation by the B-LCL. T cells treated with IO-4 or with monoclonal anti-T3 antibodies fail to respond to highly purified IL 1, and respond minimally to supra-optimal concentrations of IL 2. Nevertheless, these cells respond maximally to the accessory cell activity of the B-LCL. The IO-4 treated cells or cells exposed to anti-T3 also proliferate in response to TPA. Together, our data suggest that the B-LCL provide an IL 1-like signal for mitogen-treated T cells via direct cell contact, in the absence of detectable soluble IL 1.

Human B lymphoblastoid cell lines provide an interleukin 1-like signal for mitogen-treated T lymphocytes via direct cell contact

The B lymphoblastoid cell lines (B-LCL) 8392, SB, 1788, and Daudi provide accessory cell activity for mitogen-treated T cells, whereas the T lines MOLT-4, 8402, CEM, and HSB do not provide this function. Direct cell contact is required for the accessory cell activity, and active lymphocyte growth factors could not be detected in the supernatants of the B-LCL. The B-LCL also present alloantigens to responding T cells, and this response is independent of additional accessory cells. The target for the B-LCL is the responding T cell itself, rather than a minor contaminating population of endogenous accessory cells. This conclusion is based on the finding that, under culture conditions in which T cells do not proliferate in response to PHA, accessory cell activity of the B-LCL is maintained. Paraformaldehyde- or glutaraldehyde-treated B-LCL retain their accessory cell activity at levels of these agents that completely eliminate metabolic activity of the B-LCL, as determined by incorporation of leucine, thymidine, and uridine into macromolecules. This treatment eliminates alloantigen presentation by the B-LCL. T cells treated with IO-4 or with monoclonal anti-T3 antibodies fail to respond to highly purified IL 1, and respond minimally to supra-optimal concentrations of IL 2. Nevertheless, these cells respond maximally to the accessory cell activity of the B-LCL. The IO-4 treated cells or cells exposed to anti-T3 also proliferate in response to TPA. Together, our data suggest that the B-LCL provide an IL 1-like signal for mitogen-treated T cells via direct cell contact, in the absence of detectable soluble IL 1.

Induction of donor-specific immune modulation and successful renal transplantation with a simplified method of donor-specific blood transfusion

We developed a new method of donor-specific blood transfusion (DST) for prospective kidney transplant recipients from a living related donor. Forty-four patients were transfused with 100 ml of one-haplotype matched kidney donor's whole blood at 1, 8, and 15 days after its storage. Ten of these patients received azathioprine (1.5 mg/kg per day) in addition to DST. After DST, three patients (6.8%) developed donor-specific lymphocytotoxic antibodies. The incidence of sensitization was not different between azathioprine-treated and untreated patients. Following DST, donor-specific mixed lymphocyte culture (MLC) was significantly suppressed without any accelerated (secondary type) response in early MLC. Subsequently, 24 patients received a kidney transplant from the donor. Graft survival rates were 96% and 90% at 12 and 24 months, respectively. Nine additional patients, seven from a two-haplotype matched sibling and two from a no-haplotype matched sibling also received DST. None of these patients became sensitized following DST, and all have functioning grafts for 6 to 18 months. This study indicates that 100 ml of stored whole blood DST three times at weekly intervals is a practical, less immunizing, and effective approach to enhance graft survival in recipients of a living related donor graft, DST produces donor-specific adaptive responses that might be conductive to successful graft outcome, and this protocol could be used in sibling donor-recipient pairs who do not share a haplotype.

Cellular and humoral mechanisms in the pathogenesis of tubulointerstitial nephritis

Brown-Norway (BN) rats immunized with renal medulla from Sprague-Dawley (SD) rats developed a renal lesion characterized by focal interstitial and perivascular mononuclear cell infiltrates without glomerular involvement. The cellular infiltrates were extracted from the affected kidneys and determined to consist of monocytes 64 +/- 4% (mean +/- S.D.) and T cells 2 +/- 9%. IgG antibodies directed at tubular basement membrane and tubular cell antigens were found in the affected kidneys and in circulation. Sera of immunized rats were used in in vitro studies to determine the presence of antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). In the CDC there was cytolysis of SD kidney and spleen cells but not BN kidney cells. In the ADCC there was significant lysis of BN kidney cells as well as SD kidney cells. Antibodies have been raised in the immunized rats against major histocompatibility (MHC) antigens as well as against autologous tubular cells. The finding of monocytes bearing Fc receptors among the infiltrating cells, as well as antibodies that can function in an ADCC indicates the presence of a combined immune effector mechanism that might be operative in tubulointerstitial nephritis.

A reappraisal of the effects of monoclonal antibodies directed at T cell differentiation antigens

We examined the effects of monoclonal antibodies (Abs) directed at T3 antigen (expressed on most post-thymic T cells), T4 antigen (helper/inducer subset) and T8 antigen (suppressor/cytotoxic subset). Anti-T3 induced interleukin-2 production and proliferation of peripheral blood mononuclear cells (PBM). Anti-T4 or T8 did not exhibit such properties. Addition of methylprednisolone (MP) or cyclosporine (CsA) to PBM activated with anti-T3 resulted in 79% and 88% suppression of proliferation, respectively. Neither anti-T4 nor anti-T8 mediated significant inhibition of anti-T3-induced proliferation. Primary mixed lymphocyte cultures (MLC) were variably affected by Abs. Anti-T3 augmented proliferation found in primary MLCs at 48 hr and had an inconsistent effect on the proliferative response found at 120-136 hr of culture. Primary cytotoxic T lymphocyte (CTL) generation was consistently suppressed by anti-T3, while natural killer (NK)-cell-like activity was augmented at 72 hr and suppressed after 136 hr of culture. Anti-T4 mediated a dose-dependent suppression of proliferation and CTL generation in the primary MLC and had minimal effect on the induction of NK-cell-like activity. At high concentrations (5000-1000 ng/ml), anti-T8 mediated modest inhibition of proliferation and of the induction of cytolytic activity. Alloimmune memory cells, generated in long-term primary MLCs, were activated by anti-T3 to exhibit specific secondary cytolytic activity and NK-cell-like activity in the absence of the original priming stimulus. Neither anti-T4 nor anti-T8, under identical experimental conditions, activated memory cells. When interrelated, our experimental findings indicated that: (1) the ultimate immunity elicited by anti-T3-T3 antigen interaction is critically dependent upon the immune potential of the cell assessed; (2) MP or CsA can inhibit PBM activation by anti-T3; and (3) anti-T4 might have a role as an immunosuppressant in renal graft recipients.

Induction of cytolytic activity by anti-T3 monoclonal antibody. Activation of alloimmune memory cells and natural killer cells from normal and immunodeficient individuals

The ability of the monoclonal antibody directed at the T3 antigen (anti-T3) to induce cytolytic activity was investigated since several agents that can activate T cells induce the acquisition of cytolytic activity in a variety of test systems. Pretreatment of human alloimmune memory cells, generated in primary long-term mixed lymphocyte cultures, with anti-T3 resulted in the induction of statistically significant specific secondary cytolytic activity and natural killer (NK) cell-like activity. No such augmentation or induction of cytolytic activity was found with anti-T3 pretreatment when syngeneic cells or inappropriate allogeneic cells (HLA-A, B antigens different from the original priming stimulus) were used as target cells and pretreatment of memory cells with anti-T4 or anti-T8 did not induce cytolytic activity to allogeneic or syngeneic target cells. Differential effects were observed when anti-T3 was added to the cytotoxicity assay in which anti-T3 pretreated alloimmune memory cells were effectors. The addition of anti-T3 to the assay prior to the introduction of target cells resulted in 39 +/- 8% inhibition of specific secondary cytolytic activity and only 5 +/- 8% inhibition of NK cell activity. NK cell activity mediated by large granular lymphocyte-enriched fraction of peripheral blood mononuclear cells (PBM) obtained from normal individuals was significantly augmented by anti-T3 when NK-sensitive cell lines MOLT-4 or K-562 were used as target cells. This augmentation in NK cell activity was not associated with nonspecific cytotoxicity to syngeneic or allogeneic PBM, and anti-T3 failed to activate the LGL fraction depleted of T cells. The monoclonal antibodies, anti-T4 or anti-T8, did not increase NK cell activity. NK cell activity mediated by PBM from eight immunodeficient individuals (four with acquired immunodeficiency syndrome and four with renal allografts) was also significantly augmented by anti-T3 pretreatment. Our findings, in addition to providing a rationale for the frequent occurrence of re-rejection episodes in renal graft recipients treated with anti-T3, suggest that anti-T3 might be utilized to enhance the cytotoxic armamentarium of immunodeficient patients.

Induction of immune alterations and successful renal transplantation with a simplified method of donor-specific blood transfusion

We developed a new and simplified donor-specific blood transfusion (DSBT) protocol for prospective kidney transplant recipients from one-haplotype-mismatched related donors. Prospective kidney donors gave 450 ml of blood in a quad-pack unit, and the blood was stored in a blood bank. Twenty-five patients were transfused with 100 ml of the respective donor's whole blood at 1, 8, and 15 days after its storage. After DSBT, only three (12%) developed donor-specific lymphocytotoxic antibodies. Following DSBT, donor-specific mixed lymphocyte culture (MLC) was significantly suppressed, without any accelerated (secondary-type) response in early MLC. In addition, sera obtained after DSBT also suppressed donor-specific MLC significantly. Sixteen recipients subsequently received a kidney transplant from the donor, and all had functioning grafts at three months, but one lost the graft thereafter (graft survival rate: 94% at 12 months). This study indicates that (1) 100 ml of stored whole-blood DSBT three times at weekly intervals is a practical, less immunizing, and effective approach to enhance graft survival in recipients of a one-haplotype-mismatched graft; and (2) immune consequences of DSBT include induction of donor-specific cellular and humoral adaptive responses that might be conducive to successful graft outcome.

Hydroxyl radical scavengers inhibit human natural killer cell activity

As natural killer (NK) cell activity is an essential constituent of host defence systems and reactive oxygen intermediates participate in such defence, the effect of scavengers of oxygen radicals on NK cell activity was investigated. Hydroxyl radical (OH) scavengers (dimethyl sulphoxide (DMSO), thiourea, dimethylurea, tetramethylurea, benzoic acid, ethanol, methanol and ethylene glycol) inhibited NK cell activity. Catalase, a scavenger of H2O2, and superoxide dismutase (SOD), a scavenger of O-2, either alone or in combination, did not inhibit NK cell activity. Inhibition of the lipoxygenase pathway of arachidonic acid metabolism, a potential source of cellular OH, with nordihydroguaiaretic acid and 5,8,11,14-eicosatetraynoic acid (ETYA) resulted in marked inhibition of NK cell activity. Inhibition of the cyclooxygenase pathway with acetylsalicylic acid or indomethacin had minimal effects on NK cell activity. Taken together, these findings suggest that OH, possibly generated via the lipoxygenase pathway of arachidonic acid metabolism, is critical for NK cell cytotoxicity.

Long-term renal allograft survival in rats preimmunized with donor strain RT1.B antigens

Rat renal allograft survival was enhanced by active immunization with donor strain RT1.B (Ia) antigens. Lewis (LEW) rats (16) were immunized with Brown Norway (BN) lymphocyte extracts containing RT1.B, but not RT1.A antigens, prior to receiving (LEW X BN)F1 renal allografts. Group 1 (8 rats) was immunized with lymphocyte membrane fragments group 2(8 rats) was primed with lymphocyte supernatant extract. Longterm survivors (greater than 60 days; 12 animals) had a mean blood urea nitrogen of 75 +/- 31 mg% and serum creatinine of 2.0 +/- 0.8 mg% at one month. Death occurred in 90% of control allograft recipients within 10 days. Anti-BN RT1.B but not RT1.A antibodies were detected in sera from actively enhanced rats following immunization and at day 7 posttransplantation. We conclude that preimmunization with cell extracts containing donor RT1.B antigens has a protective effect on the allograft, and that the phenomenon of active immunologic enhancement can be produced without immunization to RT1.A antigens.

Plasmapheresis in a patient with angioimmunoblastic lymphadenopathy. Improvement in clinical and immunologic abnormalities

A patient with steroid resistant, allergen related angioimmunoblastic lymphadenopathy underwent a course of six plasmaphereses during a three-week period. A 75% reduction in lymph node size along with the disappearance of her night sweats occurred. Immunologic abnormalities prior to plasmapheresis included the presence of elevated levels of circulating immune complexes, high levels of spontaneous mononuclear cell blastogenesis and abnormal mitogen responses to Conconavalin A and phytohemagglutinin. Following plasmapheresis there was a marked reduction in immune complex levels, and return of spontaneous blastogenesis and mitogen responses to normal levels. Mechanisms for the beneficial effect seen in this patient include removal of: (1) the antigenic stimulus; (2) antigen antibody complexes; and (3) other humoral factors which may modulate lymphocyte or macrophage function. Additional studies of plasmapheresis are warranted in selected patients with allergen related AIL.

Natural history of cadaveric kidney transplants in the absence of early acute rejection

The foremost goal in organ transplantation is to achieve normal graft function without rejection. 31 (8.7%) of 357 cadaveric kidney transplant had no evidence of rejection for the first 3 months. Among these, 2 patients died with a functioning graft and four grafts failed during the 1- to 7-year follow-up period. Actuarial graft survival rates of these patients were 96.8 and 79.0% at 2 and 5 years, respectively, as compared with 64.6 and 51.2%, respectively, for the controls (p less than 0.01). Multiple preoperative blood transfusions and the adjunctive immunosuppressive therapy with retroplacental gamma globulin appeared to be playing a role for the induction of the 'no-rejection' state. However, continuous immunosuppressive therapy is necessary to maintain graft function.

Maternal-fetal immunity: presence of specific cellular hyporesponsiveness and humoral suppressor activity in normal pregnancy and their absence in preeclampsia

The hypothesis that aberrant maternal-fetal immunity might lead to the development of preeclampsia was examined using mixed lymphocyte culture reactions (MLC) as an in vitro analogue of maternal-fetal immunity. Maternal lymphocytes and serum from five normal pregnant women differed significantly from lymphocytes and serum from five preeclamptics. Maternal cells from normal pregnancy responded appropriately to unrelated control cells, but demonstrated selective hyporesponsiveness to fetal cells in the MLC. Serum from normal pregnancy suppressed MLCs when maternal cells were responder cells (RC) and maternal cells or fetal cells were stimulator cells (SC), and did not inhibit MLCs where maternal cells were RC and control cells were SC. Maternal lymphocytes and serum from preeclamptics did not demonstrate cellular hyporesponsiveness or humoral suppressor activity. Our findings support the notion that specific cellular hyporesponsiveness and humoral suppressor activity is responsible for normal pregnancy; absence of such adaptive immunity might lead to the development of preeclampsia.

Abrogation of proliferation and generation of cytotoxic T cells in human mixed lymphocyte culture reactions by modification of the cell surface with mitogenic oxidizing agents

Multiple lectins with specificity for cell surface glyco-proteins inhibit cellular and humoral immune responses and induce transplantation tolerance. Because cell surface glycoproteins play a significant role in various immune events involving cell to cell interactions and because the mixed lymphocyte culture (MLC) reaction is a prototype of immune phenomenon involving cell to cell interactions as well as an in vitro analogue of graft-destructive immune events, the effect of modification of the cell surface with oxidizing mitogens was investigated. Treatment of responder or stimulator cells with neuraminidase and galactose oxidase (NAGO) or with sodium periodate (IO-4) resulted in marked suppression of alloantigen-induced proliferation and in vitro generation of primary cytotoxic T cells (CTLs) in human MLCs. A prominent coupling of mitogen-induced proliferation to abrogation of MLC was consistently observed with modification of stimulator or responder cell surface with either NAGO or IO-4. The possibility that destruction of receptor sites and/or stimulatory units was responsible for the suppression of MLCs was excluded by restoring both proliferation and generation of primary CTLs by reduction of mitogen-oxidized cell surfaces with sodium borohydride. The ability of polyclonal activators to inhibit antigen-specific responses might be useful in abrogating unfavorable alloimmune responses.

Enhanced kidney graft survival with retroplacental source gamma-globulin. Results of a 5-year prospective study at a single center

We examined the possibility that retroplacental source gamma-globulin (RPGG), with its content of anti-HLA antibodies, would improve cadaver kidney graft survival rates. In a 5-year controlled prospective study of 208 transplants, we found that the addition of RPGG to a standard immunosuppressive drug regimen (azathioprine and prednisone) resulted in significant improvement of the cumulative survival rate (CSR) of first and second grafts. At 2 years, the overall CSR of first grafts increased from a control value of 37% +/- 6 to 52% +/- 6 (P = 0.037). Among second graft recipients, the CSR increased from a value of 19% +/- 8 to 50% +/- 10 (P = 0.014). This improvement in graft survival was seen as early as 3 months after surgery and was sustained through 3 years without added recipient morbidity or mortality. When recipient populations were stratified for various factors, those groupings remonstrative of an intact or active humoral immune response capacity were found to have the highest survival rates in the study; 2-year graft CSRs of 70% +/- 6 and 65% +/- 10 were found in recipients with preformed antibody resulting from blood transfusions (P - 0.003) and cytomegalovirus infectivity (P = 0.0006), respectively. These findings indicate that the improved graft survival seen in this study may have resulted from a recipient's immunological response to challenge with RPGG.

Immunosuppressive properties of polar organic compounds that induce cellular differentiation in Friend erythroleukemia cells

We studied the effect of several polar organic compounds, known to induce erythroid differentiation in Friend leukemia (FL) cells, on in vitro human lymphocyte responses and on skin graft survival in mice. The short chain fatty acids, butyric acid (BA), propionic acid (PA), valeric acid, and the polar organic solvents, dimethyl sulfoxide, dimethylformamide, and dimethylacetamide, all mediated significant inhibition of alloantigen-induced proliferation and generation of cytotoxic T lymphocytes (CTLs) in human primary and secondary mixed lymphocyte culture (MLC) reactions. Hexamethylenebisacetemide, another potent inducer of differentiation in FL cells, also mediated significant suppression. Inhibition of MLC with polar organic compounds was accomplished at concentrations known to induce differentiation in FL cells and that are not cytotoxic to peripheral blood mononuclear cells. In distinct contrast, agents that are structurally related to BA, but that do not induce differentiation in FL cells, such as caproic acid, beta-OHBA, gamma-amino BA, and isobutyric acid, did not exhibit immunosuppressive properties. Pokeweed mitogen-driven polyclonal B cell activation was also suppressed by agents that induce erythroid differentiation in FL cells. In addition to potent in vitro immunosuppressive properties, supplementation of drinking water with BA or PA resulted in prolongation of full-thickness skin grafts in DBA/2 (H-2d) to C57BL/6 (H-2b) donor-recipient combinations. Our findings indicate that polar organic compounds that induce differentiation in FL cells are potent immunosuppressive agents.

Declining transplantability of prospective kidney transplant recipients

The total number of cadaveric kidney transplants has been declining, despite an increasing dialysis population, greater understanding of transplant immunology, and improved transplant management. To explore the causes of this decline, various factors were studied in 140 dialysis patients who were awaiting transplantation and 100 consecutive recipients of cadaveric kidney transplants. The study indicates that there is a growing, now predominant, prospective kidney recipient population that is highly sensitized because of previous blood transfusions and kidney transplantations. As a result, 92% of the prospective recipients exhibit varying degrees of lymphocytotoxic antibodies. Thus, a major problem in clinical transplantation is the growing number of dialysis patients who are virtually untransplantable. The declining number of cadaveric kidney transplantations may be caused by, in part, changing immunologic characteristics in the recipient population.

Detection of alloimmune memory cells by chemical modification of the cell surface with mitogenic oxidizing agents

The mitogenic oxidizing agents, neuraminidase and galactose oxidase (NAGO), and sodium periodate (IO-4) were used to induce the differentiation of human alloimmune memory cells. NAGO or IO-4 treatment of peripheral blood mononuclear (PBM) cells obtained from 10 sensitized potential allograft recipients resulted in the induction and augmentation of cytolytic activity to a D locus-defined lymphoblastoid cell panel (B cell panel) and to a HLA-disparate peripheral blood lymphocyte cell panel (PBL cell panel). The acquisition of cytolytic activity was determined in a 4-hr 51Cr release assay. Treatment of in vitro-primed PBM cells (alloimmune memory cells generated in primary long-term mixed lymphocyte cultures) obtained from normal subjects with NAGO or IO-4 also resulted in the induction of specific secondary cytolytic activity. In contrast, NAGO or IO-4 treatment of unprimed PBM cells from normal subjects did not result in the induction of cytolytic activity despite the extensive proliferation induced by such treatment. The strikingly similar results observed with PBM cells from sensitized patients and with in vitro-primed PBM cells suggest that in vivo- and in vitro-generated alloimmune memory cells can be detected by chemical modification of the cell surface induced by NAGO or IO-4. Furthermore, our findings indicate that alloantigen-independent activation of memory cells can be accomplished by treating the memory cells with the mitogenic oxidizing agents.

Role of humoral presenitization in human renal transplant rejection

A prospective study of 31 cadaveric renal allograft recipients was performed to determine the significance of pretransplant presensitization undetected by the conventional microlymphocytotoxicity crossmatch. Donor-specific humoral presensitization revealed by the antibody-dependent cell-mediated cytotoxicity assay (ADCC) was associated with a high incidence of early graft rejection. Six-month graft survival was 20% in recipients with positive pretransplant ADCC and 75% in ADCC-negative recipients (P < 0.01). Among recipients highly presensitized to a random panel of HLA antigens, donor-specific humoral presensitization detected by chromium-51-release complement-dependent cytotoxicity (51Cr-CDC) was also highly correlated with accelerated rejection (P < 0.05). Pathologic study of the rejected allografts revealed antibody-mediated rejection vasculitis in all recipients. We conclude that humoral presensitization undetected by current conventional methods plays a cardinal role in early renal graft rejection and is a major factor responsible for low cadaveric renal transplant survival. This study suggests that use of the ADCC and 51Cr-CDC as routine adjunctive crossmatch procedures may contribute to improvement in renal transplant survival rates.

Immunological properties of subcellular rat lymphocyte preparations. Primary allogeneic stimulation in vitro by fractions containing Ia (RT1-B), but not RT1-A antigens

Rat thymocyte membrane fractions have been prepared which exhibit strain-specific primary mixed-lymphocyte reaction (MLR)-stimulating and Ia (RT1-B) antigenic properties. These preparations lack the antigenicity of classical, serologically-defined RT1-A (Ag-B) antigens, as defined by in vitro serologic assays. Furthermore, after immunization of allogeneic hosts, specific anti-Ia and MLR-blocking antibodies, but not anti-AgB, alloantibodies are elaborated. Thymidine suicide experiments show that the same clones respond to whole cells and the fragments made from those cells, and the response segregates appropriately in F2 progeny as a major histocompatibility complex (RT1)-linked phenomenon. Hence, it is possible to generate Ia-related allogeneic helper signals in primary, as well as secondary, in vitro responses, using subcellular membrane fragments that have restricted expression of RT1-B-, but not RT1-A-, encoded antigens.

Generation of a lymphocyte growth factor by treatment of human cells with neuraminidase and galactose oxidase

Supernates of neuraminidase and galactose oxidase (NAGO)-treated lymphocytes induce blastogenesis in nonproliferating cells harvested 7--14 d after treatment with mitogen or alloantigen and in cells incubated with mitogen for 7--14 d but not in freshly isolated peripheral blood lymphocytes9 Virtually all the growth factor is produced by NAGO-treated cells during the first 24 h of incubation, and no increase in factor activity is detected upon further cell culture. Serum is not required for growth factor production. NAGO-primed medium induces generation of specific cytotoxic T cells from mixed lymphocyte culture (MLC) memory cells to approximately the same extent as that induced by allogeneic cells (stimulating cells in the primary MLC). NAGO-primed medium provides a useful reagent for isolation and characterization of lymphocyte growth factors and other lymphokines.