Therapeutic Effect of Nile Tilapia Type II Collagen on Rigidity in CD8

Fibrillins are microfibril-associated macro glycoproteins found in connective tissues and structurally related to latent TGF-β-binding proteins (LTBPs). The special cellular immunity and blocking glycoprotein receptors IIb and IIIa of fibrillins are emerging topics in recent years. In this study, Nile Tilapia type IIcollagen (NTCII) was extracted and purified from the skull cartilages by a pepsin-soluble method. Amino acid analysis indicated that NTCII consisted of 315/1000 glycine residues, 72/1000 hydroxyproline residues and 108/1000 proline residues. SDS-PAGE analysis showed that NTCII was composed of three identical 130 kDa α-chains. The results of glycoprotein/carbohydrate assay indicated that the total polysaccharide content of NTCII was 5.6-19.0%. The IR spectrum of NTCII displayed five characteristic peaks of amide I, II, III, A, B. NTCII at 10-100 μg/mL concentration downregulated the content of cytokines in the presence or absence of LPS, especially the secretion of cytokines IL-6, IL-1β and TNF-α. Interestingly, NTCII promoted the secretion of Fas/Apo-1 compared to the control group and 25 μg/mL of NTCII resulted in a higher Fas/Apo-1 secretion level in CD8