Pharmacogenomics of Methotrexate: Current Status and Future Outlook.

BACKGROUND: Methotrexate (MTX) is a folate analogue with high therapeutic efficiency in the treatment of cancers and autoimmune diseases. The efficacy and toxicity of MTX may be altered by genetic polymorphisms in genes involved in MTX metabolic pathway. Personalized pharmacotherapy based on gene polymorphisms enables a more efficient, compatible and cost-effective treatment of patients. OBJECTIVE: The present article aims to review genetic polymorphisms associated with MTX pharmacokinetics, toxicity, and outcome, and points out future development directions of individualized MTX therapy. METHODS: Details regarding the pharmacogenetics and pharmacogenomics of MTX are obtained from PubMed literatures. CONCLUSION: The influences of single nucleotide polymorphisms (SNPs) in genes involved in MTX pathway are controversial. Many pharmacogenetic associations are disease specific and race specific. Present studies have almost limited to some certain ethnic groups and diseases. The data from these studies are not convincing enough to draw far-reaching conclusions about the applicability of MTX pharmacogenetics in clinical practice. Studies with large scale and multiple centers are needed in the future. MTX-PG inhibits folic metabolism through three mechanisms. TS, MTHFR and ATIC are the rate-limiting enzymes separately. The function of SNPs in these genes is often onesided. Works focusing on the analysis of polymorphism in MTX transporters should be more efficient and meaningful.

Expression and purification of a major allergen, Pla a 1, from Platanus acerifolia pollen and the preparation of its monoclonal antibody.

Platanus acerifolia pollen is considered an important source of airborne allergens in numerous cities. Pla a 1 is a major allergen from P. acerifolia pollen. The present study aimed to express and purify Pla a 1, and to prepare its monoclonal antibody. In the present study, the Pla a 1 gene was subcloned into a pET­28a vector and transformed into the ArcticExpress™ (DE3) RP Escherichia coli host strain. The purified Pla a 1 was then used to immunize BALB/c mice. When serum detection was positive, spleen cells were isolated from the mice and fused with SP2/0 myeloma cells at a ratio of 10:1. Hybridoma cells were screened by indirect ELISA and limiting dilution. Positive cells were used to induce the formation of antibody­containing ascites fluid, and the antibodies were purified using protein A­agarose. The results of the present study demonstrated that recombinant Pla a 1 was successfully expressed and purified, and exhibited positive immunoglobulin E­binding to serum from patients allergic to P. acerifolia. A total of 11 hybridomas that steadily secreted anti­Pla a 1 antibody were obtained and an immunoblotting analysis indicated that all of these monoclonal antibodies specifically recognized the Pla a 1 protein. These results suggested that specific anti­Pla a 1 antibodies may be obtained, which can be used for the rapid detection of Pla a 1 allergens and in the preparation of vaccines against P. acerifolia pollen.