Development of specific adsorbent for cryogel

Cryo precipitable proteins constituting in cryogel existed in patient's plasma with autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Cryofiltration was developed by Nose et al that plasma separated from the whole blood by extracorporeal blood circulation system was cooled and then cryogel is removed by the second filter. Therapeutic efficiency on these autoimmune diseases was reported. On the other hand, we have found that main components of cryogel were fibrinogen (Fbg) and fibronectin (FN). FN has molecular diversity of plasma FN (pFN) and cellular (cFN), so we investigated FN involved in cryogel. The result showed that EDA(+)FN, usually in extracellular matrix, is existed in high percentage. In this study, we prepared heparinoid cellulose sulfate as the specific adsorbent for cryogel and then examined its adsorption ability by using human plasma at 30°C. The result was that about 90% of EDA(+)FN was removed while only 50% of total FN (pFN+cFN), 20% of Fbg and ~13% of others were. Consequently this adsorbent seemed to be useful for the material of cryofiltration system.