Acute cellular rejection and cyclosporine nephrotoxicity monitored by biopsy in a renal allograft recipient. The differentiation of drug nephrotoxicity from rejection by phenotyping of cellular infiltrates

Serial allograft biopsies were performed on a renal transplant patient who experienced recurrent episodes of acute cellular rejection as well as cyclosporine nephrotoxicity. Five biopsies were performed after acute elevations of the serum creatinine level (15, 46, 155, 244, and 324 days after transplant). Each specimen was evaluated by routine histologic techniques as well as by immunofluorescence analysis and by monoclonal antibody labeling for determination of the cell phenotype of the mononuclear cell infiltrates within each specimen. The first and third specimens disclosed significant T-cell infiltrates with an equal number of T-cytotoxic-suppressor (Leu 2a) and T-helper-inducer (Leu 3a) cells in a diffuse cortical pattern, while the second biopsy showed a slightly milder infiltrate with a marked elevation (7:1) in the Leu 3a:Leu 2a ratio in the cortical-diffuse pattern. Clinically, the patient responded dramatically to cyclosporine dosage reduction following the second biopsy, and bolus steroid antirejection therapy following the first and third biopsies. These findings suggest that phenotypic cell marker analysis within the context of histologic pattern is a useful adjunct to the routine histologic evaluation of renal allograft biopsy specimens and may provide a means of differentiating rejection from cyclosporine nephrotoxicity.

Human immune responses in vivo to protein (KLH) and polysaccharide (DNP-Ficoll) neoantigens: normal subjects compared with bone marrow transplant patients on cyclosporine

Thymus-independent (TI) and thymus-dependent (TD) primary immune responses were measured in 67 controls and 13 bone marrow transplant (BMT) recipients treated with cyclosporine (CSP) by immunizing with a synthetic antigen (DNP-Ficoll) and keyhole limpet haemocyanin (KLH). DNP-Ficoll induced similar TI antibody responses in controls and BMT recipients except that antibody levels declined much more rapidly in BMT recipients. The IgM and IgG antibodies induced by DNP-Ficoll only recognized the DNP epitope and not the Ficoll carrier. Both IgM and IgG classes of antibody showed similar TI behaviour upon immunization and re-immunization. The antibodies to DNP-Ficoll were overwhelmingly of the IgG1 subclass. The TD response to KLH evoked both delayed hypersensitivity (DH) and antibody production. DH developed at the site of immunization in 68% of controls and in 88% upon subsequent challenge with KLH. None of the BMT recipients on CSP developed DH. KLH antibody arose in 88% of controls but in only one BMT recipient on CSP. Eight BMT recipients were re-immunized with KLH 2-6 weeks after stopping CSP and only one made primary DH and antibody responses, arguing that CSP inhibited priming as well as any detectable response to KLH. The immunization procedure described has proved a sensitive and comprehensive method of quantitating human immune responses in vivo and is readily adaptable for in vitro studies.

Quantitative analysis of immunosuppression in cyclosporine-treated heart transplant patients with lymphoma

Lymphoma remains an important complication after heart transplantation in the era of cyclosporine immunosuppression. It has been generally assumed that the occurrence of lymphoma related to quantitative degree of immunosuppression, and this assumption is exemplified in the treatment of some such lymphomas with reduction of immunosuppression. Seventy-five consecutive survivors of heart and heart-lung transplantation between December 1980 and July 1983 were treated with cyclosporine and steroids; some received rabbit anti-thymocyte globulin for prophylaxis or treatment of rejection. Measured quantitative parameters of immunosuppression during the first three months after transplantation included mean cyclosporine level, total rabbit anti-thymocyte globulin dosage, number of days of T-cell suppression, and mean cyclosporine level during T-cell suppression. Serial Epstein-Barr virus antibody titers were measured. Lymphoma was diagnosed in six patients. The mean number of episodes of rejection did not differ between the lymphoma and the non-lymphoma groups. All quantitative measures of immunosuppression were higher in the lymphoma group, but this difference achieved statistical significance only in the case of total dosage of rabbit anti-thymocyte globulin (p less than 0.02). Four of the six lymphoma patients received some or all of their rabbit anti-thymocyte globulin dosage as prophylaxis against rejection; one received rabbit anti-thymocyte globulin solely for rejection; and the sixth received no rabbit anti-thymocyte globulin. Ebstein-Barr virus titer conversion (four-fold rise in titer) alone was not significantly associated with occurrence of lymphoma. However, logistic regression analysis suggested that Epstein-Barr virus conversion in concurrence with high mean cyclosporine levels predicted a higher risk of lymphoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Suppression of the allergic contact reaction in the guinea pig by cyclosporin A

In a study of the effects of cyclosporin A on the allergic contact reaction to oxazolone in the guinea pig, a pronounced ability to suppress redness and edema and the dermal inflammatory cell infiltrate was demonstrated. At the generally recommended (human) organ transplantation immunosuppression dosage (20 mg/kg), a single dose gave no certain effect, but when repeated daily for 3 days, some suppression of the reaction was seen. A single 80 mg/kg dose produced marked suppression of erythema and edema and all components of the dermal cellular infiltrate. This effect was still evident, though less marked, 3 days after administration. The 80 mg/kg dose had no effect on the toxic contact reaction to croton oil. Of the agents we have previously tested (cyclophosphamide, methotrexate and azathioprine) with this model, cyclosporin A has by far the most marked capacity to suppress the allergic (cell-mediated) contact reaction, via a mechanism which would appear to involve immunomodulation rather than mere nonspecific anti-inflammatory effects.

An enzyme immunoassay for the screening of monoclonal antibodies to cyclosporin

An enzyme-linked immunosorbent assay (ELISA) has been developed which allows hybridoma cell cultures to be tested for the presence of monoclonal antibodies specific for cyclosporin A. Immunization of mice with free cyclosporin was found to be preferable to immunization with cyclosporin-carrier conjugates. It is hoped that the availability of monoclonal antibodies to cyclosporin will clarify the contribution of cyclosporin metabolites to immunosuppression and nephrotoxicity.

Cyclosporine: immunology, toxicity and pharmacology in experimental animals

Cyclosporine (CsA) is the first of a new order of pharmacological immune suppressants and represents a significant advance in the clinical control of graft rejection. In laboratory animals, its capacity to prolong allograft survival has been well documented, including reports of indefinite donor-specific immunological tolerance after shortterm CsA treatment. There is also evidence that CsA can inhibit the onset or progress of a variety of experimental autoimmune diseases. Underlying these properties of the drug is its capacity to selectively interfere with T helper cell activation and lymphokine production, although some direct effects on B cells have also been reported. In addition, sparing of suppressor cells may in part explain the mode of action of CsA which, at the molecular level, is not understood. CsA-induced nephrotoxicity in the rat has been extensively studied and is characterized by reversible proximal tubular cell damage. This problem may be aggravated by concomitant administration of other potentially nephrotoxic drugs, such as gentamicin, or by therapeutic agents which interfere with the metabolism of CsA. CsA is metabolized in the liver and excreted in the bile. Although the pathway of hepatic metabolism of CsA has not been precisely elucidated, animal studies suggest that agents capable of inducing metabolism of the drug CsA could be used to alleviate its nephrotoxic properties.

Natural killer cell activity in renal transplant recipients receiving cyclosporine

Normal subjects (n = 11) had a mean circulating natural killer (NK) cell activity of 188 lytic units per 10(7) peripheral mononuclear blood leukocytes. This activity was significantly enhanced by in vitro incubation with 500 U of alpha-interferon (+207 lytic units). The mean NK activity of renal transplant recipients on azathioprine (n = 17) or on cyclosporine (n = 17) studied at various times after transplantation was significantly decreased, as was the ability of interferon to enhance NK activity. In the cyclosporine group, interferon could not enhance NK titers 1 to 6 weeks after transplantation when the patients were on the highest doses of cyclosporine (mean, 1,002 mg/day) or when they were viremic for cytomegalovirus. After 18 weeks, when the patients received 546 mg/day or when viremia was no longer detected, the ability of interferon to enhance NK activity was more normal. Cyclosporine and cytomegalovirus infection may have a greater effect on the action of interferon on NK activity than on the NK titer per se. This defect may diminish the reserve of NK cells and contribute to post-transplant immunosuppression.

Effect of cyclosporine on the response of normal human lymphocytes to cytomegalovirus in vitro

Lymphocytes from healthy volunteers seropositive for cytomegalovirus (CMV) demonstrated strong lymphoproliferative responses to CMV-infected and glutaraldehyde-fixed foreskin fibroblasts (CMVFFx) when cocultured for 6 days. Addition of the immunosuppressive drug cyclosporine (CsA) to the cultures resulted in a 10-fold reduction (P less than 0.001) in counts per minute of [3H]thymidine uptake. The proliferative response to noninfected fixed fibroblasts was also reduced 10-fold. Kinetic studies showed an inhibition of the lymphoproliferative response and not an alteration in the time course kinetics in CsA-treated cultures. Cytotoxicity to CMV-infected and unfixed fibroblasts by lymphocytes primed by CMVFFx in the presence of 0.5 micrograms of CsA per ml was significantly reduced (P less than 0.01) as compared with untreated cultures but remained significantly above background level (P less than 0.01). The cytotoxic response was still present but reduced at concentrations of greater than or equal to 1.0 micrograms/ml. Cytotoxicity to noninfected fibroblasts by CMVFFx-primed lymphocytes could be eliminated by as little as 0.5 micrograms of CsA per ml. Stimulation of lymphocytes by CMVFFx but not by noninfected fixed fibroblasts resulted in the in vitro generation of suppressor cells. CsA at a final concentration of 1.0 or 2.5 micrograms/ml did not significantly impair the induction of cells capable of suppressing the lymphoproliferative response of fresh autologous mononuclear cells to CMVFFx. The findings described above may have important clinical implications in that a degree of protective immunity to CMV-infected cells is maintained even in the presence of CsA.

The degree of monocyte participation in human B- and T-cell activation by phorbol myristate acetate

The DNA synthetic responses of mononuclear cells (MNC), highly purified B and T lymphocytes, and T-cell subsets--OKT4+ and OKT8+ cells--and immunoglobulin production by a tumor-promoting agent, phorbol myristate acetate (PMA), were investigated. The following results were obtained: (1) PMA induced a significant DNA synthesis in MNC, pure B cells, pure T cells, and OKT4+ and OKT8+ cells. (2) Addition of monocytes to B cells did not increase the mitogenic responses more significantly than that of pure B cells alone. (3) PMA induced DNA synthesis in purified T cells significantly, but the addition of monocytes to the T cells augmented the responses markedly. (4) PMA induced polyclonal IgM production but the level of IgM synthesis was lower than that induced by PWM (about 45% at Day 6 culture). (5) Cyclosporin A (CyA) inhibited DNA synthesis induced by Con A and PHA, but did not inhibit the PMA-induced DNA synthesis. It was concluded that although there is a possibility that monocytes are not depleted completely, PMA did not seem to require monocytes for B-cell activation, whereas the level of T-cell activation was potentiated by monocyte addition and PMA probably activated T cells via receptors that are different from those used by Con A and PHA or probably activated T cells without HLA-DR antigen receptors.

Clinical trial with cyclosporin A

Six male patients with extensive psoriasis, resistant to conventional treatment, were treated orally with low-dose Cyclosporin A (CsA) (5 mg/kg/day). One patient had generalized pustular psoriasis, three psoriatic erythroderma, and two disseminated chronic plaque psoriasis. All patients, with the exception of one, were treated for at least twelve weeks. Nearly complete remission was obtained in four cases. In one patient the response was incomplete, while treatment in one case was suspended after two weeks because of the onset of cutaneous pyogenic infections and oral candidiasis. In each case a relapse was observed with the suspension of treatment.