In vivo intestinal uptake of immunoreactive bovine albumin in piglet enteritis

We examined the uptake of bovine serum albumin (BSA) from the intestine into the circulation of 3-week-old piglets infected with transmissible gastroenteritis virus. Transfer of immunoreactive bovine serum albumin (iBSA) from the intestinal lumen into the circulation was enhanced during both the early invasive phase of this viral enteritis (12-h postinoculation) and the diarrheal phase (84-h postinoculation). In some animals, enhanced uptake persisted into the recovery phase, 324 h after inoculation. Gel filtration studies suggested that iBSA had the molecular size characteristic of native BSA; no immunoreactive fragments of BSA were detected. Based on studies of two animals, the half-life of iBSA approximated that of porcine albumin. Further study is required to determine the immunological consequences of the enhanced uptake of protein occurring during viral infection of the intestine.