Of note, an increase in AP pathology by infiltrating CD4+ T-cells is not mediated through their cross-activation by antigen-presenting cells (APCs); however, the T-cell mediated cytotoxicity is driven by Fas–Fas ligand activation, as confirmed by increased Fas ligand mRNA expression following cerulein injections, resulting in increased necrosis [14]. Here, CD4 is linked to alkaline phosphatase measurement.