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PubMed1995

Effects of immunosuppressive peptidyl-prolyl cis-trans isomerase (PPIase) inhibitors, cyclosporin A, FK506, ascomycin and rapamycin, on hair growth initiation in mouse: immunosuppression is not required for new hair growth.

The effects of immunosuppressive peptidyl-prolyl cis-trans isomerase (PPIase) inhibitors, cyclosporin A, FK506, ascomycin and rapamycin, on hair growth initiation (anagen hair induction) in mouse were studied by topical application on the dorsal skin surface during the telogen phase of the hair cycle. Single applications of cyclosporin A and FK506 (10 to 100 nmol in 5 microliters of ethanol) induced new hair growth in 12 days within the restricted area where the compounds were applied. On the other hand, ascomycin and rapamycin did not initiate new anagen hairs even at higher doses (1 mumol in 5 to 10 microliters of ethanol). The effects of simultaneous application of the immunosuppressants were also tested by a single topical application. Ascomycin did not inhibit the anagen hair induction by cyclosporin A, but inhibited hair induction by FK506. Rapamycin inhibited new hair growth induced by cyclosporin A and FK506. These results suggest that the inhibition of PPIase is not required for the initiation of a new hair cycle in mice, and that anagen hair induction caused by cyclosporin A and FK506 is not a result of immunosuppression. The present results also indicate that a single application of an adequate quantity of cyclosporin A and FK506 is sufficient to initiate new hair growth.

Administration, Topical↗
PubMed2003

Immunosuppressive (FK506) and non-immunosuppressive (GPI1046) immunophilin ligands activate neurotrophic factors in the mouse brain.

Based on the fact that several recent reports have indicated that non-immunosuppressive immunophilin ligands (IPLs) can activate neurite outgrowth or nerve regeneration, we investigated the neurotrophic factor-activating abilities of IPLs in vivo in order to clarify the molecular basis of neurotrophic-like activity. Both FK506 (an immunosuppressive IPL) and GPI1046 (a non-immunosuppressive IPL) significantly increased glial cell line-derived neurotrophic factor (GDNF) content in the substantia nigra. In addition, FK506 increased striatal brain-derived neurotrophic factor (BDNF) content significantly. Thus, our present results suggest that the molecular basis of IPL-induced neurotrophic-like activity may be dependent on GDNF and/or BDNF activation.

Animals↗
PubMed1997

Review of immunosuppression for lung transplantation. Novel drugs, new uses for conventional immunosuppressants, and alternative strategies.

The history, pharmacokinetics, mechanisms of action, and experimental as well as clinical data on the immunosuppressive potential of the novel drugs tacrolimus (FK506), sirolimus (rapamycin), mycophenolic acid (mycophenolate mofetil), and leflunomide (and its malononitriloamide analogues) are provided. Novel approaches with the following conventional immunosuppressants are outlined: methotrexate, aerosolized immunosuppression and the implementation of steroid taper. Total lymphoid irradiation and photopheresis for treatment of recurrent rejection are also discussed.

Graft Rejection↗
PubMed2001

Dimeric sesquiterpene thioalkaloids with potent immunosuppressive activity from the rhizome of Nuphar pumilum: structural requirements of nuphar alkaloids for immunosuppressive activity.

Potent immunosuppressive dimeric sesquiterpene thioalkaloids, 6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B and 6'-hydroxythionuphlutine B, were isolated from the rhizome of Nuphar pumilum together with five inactive quinolizidine alkaloids, neothiobinupharidine, nupharidine, deoxynupharidine, 7-epideoxynupharidine and nupharolutine. These dimeric sesquiterpene thioalkaloids were found to significantly inhibit anti-sheep erythrocyte plaque forming cell formation in mouse splenocytes at 1 microM. At this concentration. 6-hydroxythiobinupharidine, 6-hydroxythionuphlutine B and 6'-hydroxythionuphlutine B did not show cytotoxic effects to mouse splenocytes, and 6,6'-dihydroxythiobinupharidine also showed only minor or minimal cytotoxicity. By comparison of the inhibitory activity of several Nuphar alkaloids on anti-sheep erythrocyte plaque forming cell formation, some structural requirements of Nuphar alkaloids for immunosuppressive activity were obtained. Namely, the 6- or 6'-hydroxyl group at the quinolizidine ring of dimeric sesquiterpene thioalkaloids is essential for the immunosuppressive effect. The number of hydroxyl groups appears to be related to the cytotoxicity, and the influence on splenocytes is greater with increasing numbers of hydroxyl groups.

Alkaloids↗
PubMed1998

32-Ascomycinyloxyacetic acid derived immunosuppressants. Independence of immunophilin binding and immunosuppressive potency.

The potent immunosuppressant ascomycin (1b) was selectively alkylated at the C-32 carbinol, thus providing esters and amides of 32-ascomycinyloxyacetic acid (4, AOAA). These compounds present structural variation at the FKBP/calcineurin interface. While the native carboxylic acid 4 shows no activity in vitro, esters and simple amides of 4 exhibit potent immunosuppression in the human MLR assay. Moreover, amides show inhibitory activity in the rat popliteal lymph node hyperplasia assay. Surprisingly, FKBP binding was weakened by several orders of magnitude when secondary hydrophobic aryl amides of 4 were tested, while maintaining potent immunosuppressive efficacy in vitro.

Animals↗
PubMed2005

Biochemical monitoring of mTOR inhibitor-based immunosuppression following kidney transplantation: a novel approach for tailored immunosuppressive therapy.

BACKGROUND: Immunosuppressive therapy with the mammalian target of rapamycin (mTOR) inhibitors requires a fine balance between allograft maintenance and drug-related side effects. METHODS: In this study we examined the feasibility of monitoring TOR inhibitor-based immunosuppression by assessment of the phosphorylation status at the Thr(389) site of the p70S6 kinase in peripheral blood mononuclear cells (PBMCs). At total of 36 patients with renal transplants and 8 healthy controls were enrolled. RESULTS: We found that sirolimus treatment was associated with a pronounced inhibition of p70S6 kinase phosphorylation, as compared to healthy donors or otherwise immunosuppressed patients. In sirolimus-treated patients, phosphorylation of the p70S6 kinase was significantly inhibited when sirolimus trough levels were > 6 ng/mL. In contrast, for trough levels <6 ng/mL, the degree of inhibition of p70S6 kinase phosphorylation showed a high degree of interindividual variability. We recorded a total of five clinical relevant rejection episodes in this patient category. Intriguingly, rejecters uniformly maintained a high degree of phosphorylation independent of the sirolimus trough level whereas non-rejecters showed a significant inhibition of phosphorylation. CONCLUSION: Therefore, the phosphorylation status of the p70S6 kinase appears to provide more relevant information on the desired effect of sirolimus in target cells as compared to trough level measurements. Moreover, this assay provides an opportunity to safely titer down sirolimus levels to avoid overimmunosuppression and, on the other hand, to identify patients with insufficient TOR inhibitor therapy that are at risk for rejection.

Adult↗
PubMed1976

Influence of immunosuppression on the action of antimycobacterial drugs in experimental tuberculosis. I. Effects of isoniazid, rifampicin and streptomycin on the survival of tuberculous mice immunosuppressed by azathioprine (Imuran).

The influence of the host immunosuppression on antimycobacterial effects of isoniazid, rifampicin or streptomycin was studied on animal models. Differences in survival rates of mice influenced or uninfluenced by azathioprine (Imuran) and exposed to six applications of antituberculous drugs (given once a day in the monotherapy) were statistically evaluated. The dose-dependent antimycobacterial effects of rifampicin or isoniazid were not significantly altered by the immunosuppression of the host. In contrary to that definite dose-dependent effect of streptomycin, observed in azathioprine-uninfluenced mice, cannot be confirmed in immunosuppressed mice in which no effect of streptomycin on the survival of tuberculous mice could be estimated.

Animals↗
PubMed2000

Lymphomas in patients with connective tissue disease. Comparison of p53 protein expression and latent EBV infection in patients immunosuppressed and not immunosuppressed with methotrexate.

Cell cycle dysregulation as measured by p53 protein expression and latent Epstein-Barr (EBV) infection are important in the pathogenesis of lymphoma, particularly in immunosuppressed patients. Although latent EBV commonly is detected in lymphomas arising in patients with connective tissue disease who are immunosuppressed with methotrexate, p53 protein expression has not been reported. We compared the immunohistologic expression of p53 protein and the incidence of latent EBV infection in lymphomas arising in patients with connective tissue disease treated and not treated with methotrexate. Increased p53 staining was detected in 10 of 11 lymphomas arising in patients after methotrexate therapy vs 5 of 11 in patients not treated with methotrexate. Latent EBV was detected in 7 of 13 lymphomas arising in patients after methotrexate therapy vs 2 of 11 in patients not treated with methotrexate. Concordant p53 expression and latent EBV were detected in 5 of 7 lymphomas arising after treatment with methotrexate, including 1 that regressed after methotrexate therapy was withdrawn. These findings suggest that cell cycle dysregulation and EBV-related transformation are important in the pathogenesis of lymphomas arising in patients with connective tissue disease who are immunosuppressed with methotrexate.

Adolescent↗
PubMed1991

Dunaimycins, a new complex of spiroketal 24-membered macrolides with immunosuppressive activity. III. Immunosuppressive activities of dunaimycins.

The immunosuppressive effects of the dunaimycins, a new complex of spiroketal 24-membered macrolides, were compared to cyclosporin A, ascomycin, and rapamycin. Each dunaimycin was a potent inhibitor of the mitogenic response observed in mixed murine splenocyte or human leukocyte cultures, and like immunosuppressive drugs these compounds were relatively less potent inhibitors of the constitutive proliferation of murine EL4 thymoma cells. Dunaimycin D4S showed no selectivity in inhibiting the mitogenic response of spleen cells to concanavalin A, pokeweed mitogen, lipopolysaccharide, or phytohemagglutinin. Cyclosporin A and ascomycin did not inhibit interleukin 2 dependent proliferation, whereas the dunaimycins and rapamycin blocked the uptake of [3H]thymidine in mixed cultures supplemented with exogenous interleukin 2. In addition, dunaimycin D4S had no apparent affinity for cyclosporin A or FK-506 immunophilins. Although the dunaimycins inhibited the activity of Na+, K(+)-ATPase, inhibition of this enzyme appeared insufficient to explain the biological activity of these new macrolides. Over a narrow concentration range, dunaimycin D4S showed in vivo immunosuppressive activity in the murine popliteal lymph node hyperplasia model.

Animals↗
PubMed1984

[Induction of immunosuppression by dietary aversion acquired in the absence of immunosuppressive treatment].

Conditioned taste aversion induced by either an immunosuppressive (cyclophosphamide) or non immunosuppressive (lithium chloride) drug reduced expression of a T cell mediated immune response that is highly susceptible to stress hormones. These results demonstrate that the proposed concept of conditioned immunosuppression really represents another example of how stress can alter normal regulation of cell mediated immune events.

Animals↗
PubMed1982

[Clinical evaluation of the serum level of immunosuppressive acidic protein (IAP) and immunosuppressive substance (IS) in gastric cancer patients].

Recently, immunosuppressive acidic protein (IAP) and immunosuppressive substance (IS) were reported by two institutions, and they have been currently under extensive clinical investigations. As these two acidic proteins seemed to be very similar glycoproteins, we tried to elucidate clinically the dissimilarities between these two substances. The mean value of IAP of 106 healthy donors was 378 +/- 100 micrograms/ml, and as 95% of them was under 550 micrograms/ml, therefore, the upper limit of normal value of IAP was determined to be 550 micrograms/ml. On the other hand, the mean value of IS was 553 +/- 125 micrograms/ml and the upper limit of normal value was 750 micrograms/ml. In 110 gastric cancer patients, the incidence of the abnormal value of IS (43%) was higher than that of IAP (33%), and abnormal values were observed at earlier stage in IS than that observed in IAP. The reaction of skin tests was more highly correlated with the value of IS than the value of IAP. From these facts, it was suggested that the value of IS was more predictable than that of IAP as the parameter of the immunosuppression of the gastric cancer patients.

Adolescent↗
PubMed2006

Cancer immunosuppression and autoimmune disease: beyond immunosuppressive networks for tumour immunity.

Cancer immunosuppression evolves by constitution of an immunosuppressive network extending from a primary tumour site to secondary lymphoid organs and peripheral vessels and is mediated by several tumour-derived soluble factors (TDSFs) such as interleukin-10 (IL-10), transforming growth factor-beta (TGF-beta) and vascular endothelial growth factor (VEGF). TDSFs induce immature myeloid cells and regulatory T cells in accordance with tumour progression, resulting in the inhibition of dendritic cell maturation and T-cell activation in a tumour-specific immune response. Tumour cells grow by exploiting a pro-inflammatory situation in the tumour microenvironment, whereas immune cells are regulated by TDSFs during anti-inflammatory situations--mediated by impaired clearance of apoptotic cells--that cause the release of IL-10, TGF-beta, and prostaglandin E2 (PGE2) by macrophages. Accumulation of impaired apoptotic cells induces anti-DNA antibodies directed against self antigens, which resembles a pseudo-autoimmune status. Systemic lupus erythematosus is a prototype of autoimmune disease that is characterized by defective tolerance of self antigens, the presence of anti-DNA antibodies and a pro-inflammatory response. The anti-DNA antibodies can be produced by impaired clearance of apoptotic cells, which is the result of a hereditary deficiency of complements C1q, C3 and C4, which are involved in the recognition of phagocytosis by macrophages. Thus, it is likely that impaired clearance of apoptotic cells is able to provoke different types of immune dysfunction in cancer and autoimmune disease in which some are similar and others are critically different. This review discusses a comparison of immunological dysfunctions in cancer and autoimmune disease with the aim of exploring new insights beyond cancer immunosuppression in tumour immunity.

Animals↗
PubMed2005

Transplant-related immunosuppression: a review of immunosuppression and pulmonary infections.

Solid organ and hematopoietic stem cell transplantation are definitive therapies for a variety of end-stage diseases. Immunosuppression has improved graft survival but leaves the patient susceptible to infectious complications. Of these, pulmonary infections are the leading cause of morbidity and mortality in the transplant recipient. Allograft rejection is mediated primarily by T cells, with B cells playing a role via antibody production. Depending on the transplant type, rejection can be hyperacute, acute, or chronic. Hyperacute rejection occurs as an immediate response to preformed antibodies to donor human leukocyte antigens. Acute cellular rejection involves recipient T-cell recognition of human leukocyte antigen molecules expressed on donor-derived, antigen-presenting cells (direct allorecognition) or presentation of donor-derived peptides by recipient antigen-presenting cells to recipient T cells (indirect allorecognition). Once the alloantigens are recognized as foreign, the activation, proliferation, and production of cytokines by T lymphocytes and other immune cells lead to the amplification of the alloimmune response. This complex process involves the generation of effector T cells, antibody production by activated B cells, and macrophage activation. Alloimmunity is facilitated by the production of many cytokines, chemokines, and other effector molecules, such as complement. The immunosuppressants involve many classes of drugs, including antibody therapies that eliminate specific groups of cells or alter signaling pathways used by effector cells. The article reviews the agents and associated infections.

Female↗
PubMed1991

Renal allograft immunosuppression. VI. Triple drug therapy versus immunosuppressive double drug combinations: histopathological findings in renal allografts.

The long-term effects of different immunosuppressive drugs and regimens on renal allograft histology are virtually unknown. Therefore, in order to investigate the long-term effects of triple drug treatment versus different combinations of two immunosuppressive drugs on allograft histology, a prospective, randomized trial was performed. One group received triple therapy consisting of low-dose cyclosporin (CyA), azathioprine (Aza), and methylprednisolone (MP), and three groups received combinations of two drugs, i.e., Aza plus CyA, Aza plus MP, and CyA plus MP. At 2 years, there were no significant differences with regard to graft (80%) or patient (87%) survival, or to graft function between the four groups. After 2 years, a protocol core biopsy was taken of all 102 patients having a functioning graft. Of these patients, 61 (60%) were still following the original, randomized treatment protocol; in the remaining cases, changes had occurred in the original protocol and so these cases were considered drop-outs in this study. Histological specimens were examined blindly by two independent observers. Most of the 34 histological variables examined showed no changes. Diffuse fibrosis was most frequent in the CyA plus MP group (70%) and significantly more severe than in the triple therapy group. Mesangial matrix increase in glomeruli was significantly less common in the triple therapy group (8%) than in any one of the double drug combination groups (47%). Two other changes in glomeruli--Bowman capsular thickening and global glomerular sclerosis--were also less frequent in the triple therapy group.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug Therapy, Combination↗
PubMed1984

Comparison of the immunosuppressive effect of fractionated total lymphoid irradiation (TLI) vs conventional immunosuppression (CI) in renal cadaveric allotransplantation.

Beginning in November 1981, eight patients with end stage diabetic nephropathy underwent renal cadaveric transplantation after TLI. Transplantation was done between 2 to 11 days after the end of a fractionated TLI to a total dose of 20 to 30 Gy. During the same observation period, 60 nondiabetic patients with end stage renal disease of different origin also received a cadaveric kidney graft, with a conventional regimen of immunosuppression that consists of anti-lymphocyte-globulin, tapering high doses of prednisone, and azathioprine. In the TLI-treated group only a low maintenance dose of prednisone (15 mg) was given. Immunologic monitoring was performed after transplantation at regular intervals and was compared in both groups. Phytohemagglutinin (PHA)-, concanavalin A (con A)-, and pokeweed mitogen (PWM)-induced blastogenesis, as well as the mixed lymphocyte reaction (MLR) and the cell-mediated lympholysis (CML) decreased progressively during the first months after conventional immunosuppression to 50% of the pretransplantation level, and remained there for the first year after transplantation. These tests were much more impaired after TLI (less than 15% of pre TLI value) and again no recovery occurred during the first year. Natural killer (NK) cell activity progressively decreased from a mean value of 53% lysis before transplantation to 15% lysis at the end of the first year after transplantation in the conventionally treated patients. In TLI-treated patients, however, the NK activity, which declined during irradiation from 46% specific lysis to 12%, recovered rapidly after TLI to reach levels of 35 to 40% of specific lysis from the second month on after TLI. In both groups of patients the ratio of helper-inducer (TH) to suppressor-cytotoxic (TS) lymphocytes, as determined with monoclonal antibodies, progressively declined during the first 2 mo after transplantation to a low value of about 1.2. In TLI-treated patients however, this fall progressed further, so that very low levels (less than 0.6) were noticed from the third month on after TLI. The decline of the TH:TS ratio after TLI is due to an absolute increase in the number of suppressor cells. This is in contrast with the conventionally treated patients, where the low ratio is mainly provoked by a more important decrease of the helper cell population. These changes in the balance between TH and TS subpopulations are more frequently associated with positive functional suppressor cell assays in the TLI-treated patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Cadaver↗
PubMed1996

Overview of a 10-year experience on methods and compositions for inducing site-specific immunosuppression with topical immunosuppressants.

Methods and formulations have been successfully developed to bring about site-specific immune suppression of local T-cell-mediated immune responses involved in contact hypersensitivity, skin allograft rejection, and, putatively, autoimmune inflammatory conditions such as psoriasis. The induction of site-specific immune suppression results in reduced systemic pharmacology and toxicity. Certain formatulations have been devised that can effect dramatic transdermal drug delivery and systemic immunopharmacology. Local site-specific or systemic efficacy by transdermal delivery can be dependent upon carrier composition with respect to the hydrophilic/lipophilic nature of the solvent system, active principal solubilization, and concentration. Multiple classes of active immunosuppressive agents can be successfully combined to produce novel and extremely potent topical drugs. Specifically, either cyclosporine or rapamycin inhibit local inflammatory/immune responses by topical application to skin tissue in vivo. Rapamycin is particularly efficacious during the late local inflammatory/immune phase. Cyclosporine is particularly efficacious during the early local inflammatory-immune phase. Also, skin allograft survival may be prolonged via topical use of CyA, alone and in combination with other anti-inflammatory agents. This includes combined immunosuppressant and steroidal anti-inflammatory agents that can produce synergistic results. Systemic immunity in these instances is normal. Expression of MHC class I and MHC class II molecules is dramatically decreased in these CyA/steroid SITE-treated grafts. In summary, the induction of local immune suppression at the tissue site and focal responding immunocytes can result in surprising efficacy when used in conjunction with limited systemic administration, which could have significant immunologic and clinical ramifications.

Administration, Topical↗
PubMed1985

Towards the Belfast immunosuppressive regimen: a prospective trial of low versus high dose steroids and once versus twice daily immunosuppression.

The Transplant Unit in Belfast achieves the highest survival rates in Great Britain for renal transplants. The immunosuppression used comprises azathioprine and very low doses of steroids administered just once a day. The importance of these features has been examined in two clinical trials using (a) high or low dose steroids with azathioprine, (b) low dose steroids with azathioprine given once or twice daily following cadaveric renal transplantation. Low dose steroids were no more effective than were high dose steroids in preventing graft rejection and there was no advantage in administering immunosuppression once daily in the morning as opposed to twice daily in divided doses. None the less, with low doses of steroids the complications of cushingism and obesity were markedly reduced. Neither trial achieved the degree of success in transplant survival that has been usual in Belfast.

Adult↗
PubMed1997

Immunosuppressive retroviral peptides: immunopathological implications for immunosuppressive influences of retroviral infections.

Studies of the effects of retroviruses on the immune system, which date back through thirty years of investigations, are reviewed. In the earliest published studies in the 1960s, it was demonstrated that mice infected with oncogenic viruses were immunosuppressed. Since then, numerous articles have been published describing profound immunodeficiencies observed in vivo in humans infected with human immunodeficiency virus and in animals such as cats infected with the feline immunodeficiency virus. In vitro investigations have shown that inactivated retroviruses or transmembrane envelope protein p15E as well as a synthetic 17-amino acid peptide (CKS-17) impressively conserved within the transmembrane envelope protein of several animal or human retroviruses are highly immunosuppressive. More recently, dysfunction of cytokines produced by CKS-17 at both a cellular and molecular level have been found to mimic influences observed in vivo in patients infected with the human immunodeficiency virus. CKS-17 has also been shown to induce cAMP in vitro. The significance of these observations to understanding the immunological disturbances observed in malignancy, cytokine biosynthesis, and modulations of immune functions through cAMP is discussed.

Amino Acid Sequence↗