HAPLN1 and rheumatoid arthritis: As the current molecular interaction network of HAPLN1 is barely barren, to get acquaintance with HAPLN1 functions in RA-FLSs from a more comprehensive view, proteomics and transcriptome analyses were done with rHAPLN1 treated or si-HAPLN1 transfected RA-FLSs to further investigate HAPLN1 functions in RA-FLSs.