PTPN22 and rheumatoid arthritis: To detect the effect of the MSNs@PCM@TP + 808 nm laser on the expression of PTPN22 in RA rats, we compared the mRNA and protein levels of PTPN22 in the thymus and spleen of rats treated with 100 μg/ml of MSNs@PCM@TP + 808 nm laser for 1 week with those of the RA and RA + TP groups.