Upregulation of the stress marker BiP/GRP78 was seen in pancreatic parenchyma obtained both from Cel-HYB1 animals and from a human CEL-HYB1 carrier.<h4>Conclusions</h4>We have developed a new mouse model for CP that confirms the pathogenicity of the human CEL-HYB1 variant. This evidence concerns the gene HSPA5 and Chronic Eosinophilic Leukemia, Not Otherwise Specified.