Human CD55 encodes a protein involved in the regulation of the complement cascade. The encoded glycoprotein is also known as the decay-accelerating factor (DAF); binding of DAF to complement proteins accelerates their decay, disrupting the cascade and preventing damage to host cells. Antigens present on the DAF glycoprotein constitute the Cromer blood group system (CROM). Two alternatively spliced transcripts encoding different proteins have been identified. The predominant transcript encodes a membrane-bound protein expressed on cells exposed to plasma component proteins but an alternatively spliced transcript produces a soluble protein present at much lower levels.

Recombinant human CD55 (Isoform-1) extracellular domain cDNA (35-353 aa fragment) was constructed with codon optimization and expressed with small T7 Tag (29aa) fusion at its N-terminal and expressed in E.coli as inclusion bodies. The final product was refolded using our unique “temperature shift inclusion body refolding” technology and chromatographically purified. Coating this recombinant protein at 5-10 ug / well (6 well plate) in a specific culture medium can be used for human red blood cell differentiation study in vitro.

1. Protein can be used as coating matrix protein for study human red blood cell differentiation regulation in vitro.

2. Potential biomarker protein for anto-immuno disease diagnostic development.

1. Purity: > 90% by SDS-PAGE.

2. Functional Test: Not tested yet.