Safety evaluation of a whey protein fraction containing a concentrated amount of naturally occurring TGF-β2.

TM0601p is a whey protein isolate derived from cow milk, containing a concentrated amount of transforming growth factor β2 (TGF-β2), and is intended for nutritional use in infants and adults. In vivo and in vitro studies have been performed to evaluate the safety of this product. In a 13-week toxicity study, treatment of adult Sprague-Dawley rats by gavage at up to 2000mg/kg/day did not result in any significant findings other than minor non-adverse changes in urinary parameters in females. The no-observed-adverse-effect level (NOAEL) was established as 2000mg/kg/day. In a juvenile toxicity study, rat pups received 600mg/kg/day by gavage from postnatal day (PND) 7 to PND 49. Transient lower bodyweight gain in the pre-weaning period was attributed to gastrointestinal effects of the viscous test material; following weaning, bodyweight gain was comparable to the vehicle controls. Reduced eosinophil counts and changes in urinary parameters (females) were recorded in treated pups at PND 49, and higher thymus weights were recorded in males only at the end of the recovery period (Day 77). None of the findings were considered adverse. There were no other significant findings and the NOAEL was established as 600mg/kg/day. No evidence of genotoxicity was seen in the bacterial reverse mutation test or the in vitro micronucleus test. Overall the results obtained present a reassuring safety profile for TM0601p.