Detection of prospective biomarkers of response to J apanese traditional ( K ampo) medicines in patients with rheumatoid arthritis using immune response biomarker profiling

Aim In J apan, K ampo medicine ( KM ) plays a critical role in primary health care, and also in the treatment of several serious diseases such as rheumatoid arthritis ( RA ). Although traditional diagnostic methods are able to discriminate responders from non‐responders to KM , the aim of this study was to propose a methodology to translate the traditional diagnosis, and identify a predictive biomarker of the beneficial effect of KM in RA patients. Methods Three groups (healthy controls; non‐responders to keishinieppiittokaryojutsubu ( KER ; representative KM formula for RA ); and responders to KER ) were investigated, and each group included five people. Autoantibody profile from the sera obtained from each group was analyzed using immune response biomarker profiling. A candidate biomarker autoantibody was identified using G enepix microarray systems. Results In responders to KER , autoantibodies to family with sequence similarity 219, member A ( FAM219A ; previously known as C9orf25 ) were detected. In contrast, autoantibodies to zinc finger, FYVE domain containing 19 ( ZFYVE19 ) were detected in non‐responders. Conclusions Candidate biomarkers for discriminating responders from non‐responders to KER for RA were identified. The present results may open the way to the standardization of the K ampo diagnostic system, and to classify RA patients according to immune status.