Recombinant human sphingomyelin phosphodiesterase 2 (SMPD2) is produced using an in vitro E. coli expression system. The gene encoding the full-length SMPD2 protein (amino acids 1-423) is cloned into an appropriate expression vector with suitable regulatory elements. Following cloning, the recombinant plasmid DNA is isolated and purified. Subsequently, an in vitro transcription reaction is performed using the purified plasmid DNA as a template, resulting in the synthesis of mRNA. This mRNA is then used in an in vitro translation reaction to synthesize the recombinant human SMPD2 protein. The protein is purified from the reaction mixture and its purity is confirmed through SDS-PAGE analysis. The recombinant SMPD2 protein exhibits a purity level of up to 90% and migrates as a band with a molecular weight of 44 kDa on the SDS-PAGE gel.