Cal jẹ heterodimer, eyiti o jẹ ti MRP 8 ati MRP 14. O wa ninu cytoplasm neutrophils ati ti a fihan lori awọn membran sẹẹli mononuclear.Cal jẹ awọn ọlọjẹ alakoso nla, o ni ipele iduroṣinṣin daradara ni bii ọsẹ kan ninu awọn ifun eniyan, o pinnu lati jẹ ami ami aisan ifun iredodo.Ohun elo naa jẹ irọrun, idanwo semiqualitative wiwo ti o ṣe awari cal ninu awọn ifa eniyan, o ni ifamọra wiwa giga ati ni pato to lagbara.Idanwo naa ti o da lori pato awọn ọlọjẹ ilọpo meji ti ipanu ipanu ipanu ati awọn imọ-ẹrọ itupalẹ idanwo immunochromatographic goolu, o le fun abajade laarin awọn iṣẹju 15.