CHO cells expressing mammalian PSGL 1 effectively roll on human L or P selectin The role of PSGL one in regulating CHO PSGL one cell rolling on human L or P selectin was assessed beneath hydrody namic movement disorders. Human PSGL 1 expressing cells had been much less recruited on human P selectin than CHO cells expressing bovine PSGL one. Also, on human L selec tin, cell recruitment of CHO cells expressing human PSGL one was much less productive than that of cells expressing bovine, pig or rat PSGL 1. Surprisingly, CHO cells expressing equine PSGL one didn’t roll on P selectin and had been weakly recruited on L selectin. Previous studies showed that N terminal tyrosine sulfate residues are involved in supporting human PSGL 1 dependent rolling on L and P selectin.
Human, bovine, rat and pig PSGL 1 exhibit two or three probable N terminal tyrosine sulfation sites, Cilengitide ic50 whereas equine PSGL KU60019 one incorporates just one single website. The contribution of PSGL 1 sulfation to cell rolling was assessed by comparing recruitment of CHO cells express ing control or desulfated human, bovine, rat, pig and equine PSGL one on L or P selectin. Inhibition of PSGL one sulfation strongly diminished L and P selectin dependent rolling. The recruitment of CHO cells express ing human PSGL one, on P selectin, was inhibited by 88 5%, whereas the recruitment of cells expressing bovine, rat and porcine PSGL 1 was nearly abrogated. Rolling inhibition induced by desulfation was also observed on L selectin. Thus, as previously described for human PSGL 1, sul fation of bovine, pig, rat or equine PSGL 1 N terminal tyrosine residues is needed to support PSGL 1 depend ent rolling on L or P selectin.
Interestingly, various sequence alignment of mamma lian L or P selectin exhibits partial or finish conserva tion of amino acid residues that regulate human selectin binding to PSGL one tyrosine sulfate residues. Ser 47, Lys 112 and His 114 on human P selectin bind to human PSGL 1 Tyr 48, though human L selectin Lys 85 and P selectin Arg 85 interact with Tyr 51. In mammalian P selectins, Ser 47 is conserved, except for bat and rhesus monkey, and Lys 112 and His 114 is either conserved or replaced by arginine, which may interact with sulfated Tyr 48. Except for pig and Mammalian neutrophil recruitment on human L or P selectin is heterogeneous The impact of PSGL one glycosylation by mammalian FucT VII and C2GnT I on PSGL 1 dependent rolling on human L or P selectin was assessed below numerous shear stresses. The recruitment of bovine, porcine, rat and equine neutrophils on human L or P selectin strongly differed from that on the corresponding CHO PSGL one cells. At one.