Suppression of allograft rejection is central to successful organ transplantation; thus, immunosuppressive agents are crucial for successful allograft function. Immunosuppressive drugs are used for induction (intense immunosuppression in the initial days after transplantation), maintenance, and reversal of established rejection. This review considers the use of immunosuppressive drugs in organ transplantation, focusing on renal transplantation.

https://www.nejm.org/doi/pdf/10.1056/NEJMra033540

Immunosuppressive Drugs for Kidney Transplantation

THE structurally novel macrolide FK506 (refs 1,2) has recently been demonstrated to have potent immunosuppressive activity3–7 at concentrations several hundredfold lower than cyclosporin A (CsA). Cyclosporin A, a cyclic peptide, has found widespread clinical use in the prevention of graft rejection following bone marrow and organ transplantation8. The mechanisms of immunosuppression mediated by FK506 and CsA appear to be remarkably similar, suggesting that these unrelated structures act on a common receptor or on similar molecular targets, perhaps the CsA receptor, cyclophilin9–11, which has recently been shown by Fischer etal.12 and Takahashi etal.13 to have cis–trans peptidyl-prolyl isomerase activity. We have prepared an FK506 affinity matrix and purified a binding protein for FK506 from bovine thymus and from human spleen. This FK506-binding protein (FKBP) has a relative molecular mass (Mr) of ∼14,000(14K), a pi of 8.8–8.9, and does not cross-react with antisera against cyclophilin. The first 40 N-terminal residues of the bovine and 16 residues of the human FKBP were determined; the 16-residue fragments are identical to each other and unrelated to any known sequences. This protein catalyses the cis–trans isomerization of the proline amide in a tetrapeptide substrate and FK506 inhibits the action of this new isomerase. The FKBP and cyclophilin appear to be members of an emerging class of novel proteins that regulate T cell activation and other metabolic processes, perhaps by the recognition (and possibly the isomerization) of proline-containing epitopes in target proteins.

A receptor for the immunosuppressant FK506 is a cis-trans peptidyl-prolyl isomerase.

Nucleotide-binding oligomerization domain protein 1 (NOD1) belongs to a family that includes multiple members with NOD and leucine-rich repeats in vertebrates and plants. NOD1 has been suggested to have a role in innate immune responses, but the mechanism involved remains unknown. Here we report that NOD1 mediates the recognition of peptidoglycan derived primarily from Gram-negative bacteria. Biochemical and functional analyses using highly purified and synthetic compounds indicate that the core structure recognized by NOD1 is a dipeptide, γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP). Murine macrophages deficient in NOD1 did not secrete cytokines in response to synthetic iE-DAP and did not prime the lipopolysaccharide response. Thus, NOD1 mediates selective recognition of bacteria through detection of iE-DAP-containing peptidoglycan. *Note: In the version of this article initially published online, one author's first name and last name were reversed. The correct author name should be Su Qiu. This mistake has been corrected for the HTML and print versions of the article.

An essential role for NOD1 in host recognition of bacterial peptidoglycan containing diaminopimelic acid.

The immuno-pharmacological profile of a novel immunosuppressive agent, FK-506 produced by a streptomycete, is presented here. We proceeded to test the effect of the agent on various in vitro immune systems. It showed that mixed lymphocyte reaction, cytotoxic T cell generation, the production of T cell-derived soluble mediators such as interleukin 2 (IL-2), interleukin 3 and gamma-interferon and the expression of the IL-2 receptor were suppressed by this agent. The IC50 values of FK-506 and ciclosporin (CS) in all tests were approximately 0.1nM and 10nM, respectively. Therefore, the novel agent, FK-506 suppressed in vitro immune systems at about hundred times lower concentration than CS.

https://www.jstage.jst.go.jp/article/antibiotics1968/40/9/40_9_1249/_pdf

FK-506, a novel immunosuppressant isolated from a Streptomyces. II. Immunosuppressive effect of FK-506 in vitro.

FK-506, a novel immunosuppressant, has been isolated from the fermentation broth of Streptomyces tsukubaenis No. 9993 as colorless prism and the molecular formula was determined as C44H69NO12.H2O. The compound suppressed immune responses in vitro and in vivo with mice. This immunosuppressive effect was more potent than that of ciclosporin.

FK-506, a novel immunosuppressant isolated from a Streptomyces. I. Fermentation, isolation, and physico-chemical and biological characteristics.

Structure of FK506, a novel immunosuppressant isolated from Streptomyces

Structure of FR 900482, a novel antitumor antibiotic from a Streptomyces

Physicochemical properties of FK-506, a novel immunosuppressant isolated from Streptomyces tsukubaensis.

Nocardicin A and B, monocyclic .beta.-lactam antibiotics from a Nocardia species

A compound of the formula :
 wherein R 1 is lower alkyl optionally substituted with a substituent selected from the group consisting of acyl,hydroxy, lower alkoxy, aryl, lower alkylthio and a group of the formula :
 in which R 5 is hydrogen or acyl and
 R 6 is hydrogen or lower alkyl; aryl; or amino optionally substituted with substituent(s) selected from the group consisting of lower alkyl and acyl; and R 2 is hydrogen or lower alkyl; or R 1 and R 2 are taken together with the attached nitrogen atom to form a heterocyclic group optionally substituted with substituent(s) selected from the group consisting of lower alkyl, hydroxy(lower)alkyl, lower alkoxy(lower)alkyl, acyl(lower)alkyl, oxo and acyl; R 3 is hydrogen or lower alkyl; and R 4 is lower alkyl; and its pharmaceutically acceptable salt, processes for the preparation thereof and pharmaceutical composition comprising the same.

Masashi Hashimoto

Papers

Structure of FK506, a novel immunosuppressant isolated from Streptomyces

Structure of FR 900482, a novel antitumor antibiotic from a Streptomyces

Physicochemical properties of FK-506, a novel immunosuppressant isolated from Streptomyces tsukubaensis.

Nocardicin A and B, monocyclic .beta.-lactam antibiotics from a Nocardia species

New amino acid derivatives, processes for the preparation thereof and pharmaceutical composition comprising the same