SERUM IMMUNOGLOBULIN-G DIRECTED AGAINST PORCINE TRYPSIN IN THE SERUM OF CYSTIC-FIBROSIS CHILDREN RECEIVING PORCINE PANCREATIC-ENZYME SUPPLEMENTS

Cystic fibrosis (CF) patients require pancreatic enzyme replacement th erapy to correct pancreatic insufficiency. These enzymes are derived f rom porcine pancreas and are known to be antigenic. To determine the p ossible clinical consequences, a specific ELISA was developed to detec t IgG antibody directed against porcine trypsin (PTAb) in the sera of CF patients. The assay was used to evaluate the occurrence of PTAb in a cross sectional study of 103 CF patients in relation to the introduc tion of porcine enzyme therapy, clinical status and genotype. Antibodi es against porcine trypsin were detected in the sera of 63% of patient s unrelated to the age of commencement or the duration of enzyme thera py. No differences were observed in the clinical status of CF patients who had developed PTAb (n = 65) and those who had no detectable PTAb (n = 38) as determined from: the current prescribed dose of porcine pa ncreatic enzyme capsules; Z scores for height and weight; and respirat ory function tests. It is suggested that the PTAb commonly found in th e sera of CF patients are of doubtful clinical significance but the pr ospect of PTAb contributing to immune complex disease should be examin ed further.