Consumption of transgenic cows' milk containing human lactoferrin results in beneficial changes in the gastrointestinal tract and systemic health of young pigs.

Lactoferrin is an antimicrobial and immunomodulatory protein that is produced in high quantities in human milk and aids in the gastrointestinal (GI) maturation of infants. Beneficial health effects have been observed when supplementing human and animal diets with lactoferrin. A herd of genetically engineered cattle that secrete recombinant human lactoferrin in their milk (rhLF-milk) have been generated which provide an efficient production system and ideal medium for rhLF consumption. The effects of consumption of rhLF-milk were tested on young pigs as an animal model for the GI tract of children. When comparing rhLF-milk fed pigs to non-transgenic milk fed pigs (control), we observed that rhLF-milk fed pigs had beneficial changes in circulating leukocyte populations. There was a significant decrease in neutrophils (p = 0.0036) and increase in lymphocytes (p = 0.0017), leading to a decreased neutrophil to lymphocyte ratio (NLR) (p = 0.0153), which is an indicator of decreased systemic inflammation. We also observed changes in intestinal villi architecture. In the duodenum, rhLF-milk fed pigs tended to have taller villi (p = 0.0914) with significantly deeper crypts (p < 0.0001). In the ileum, pigs consuming rhLF-milk had villi that were significantly taller (p = 0.0002), with deeper crypts (p < 0.0001), and a thinner lamina propria (p = 0.0056). We observed no differences in cytokine expression between rhLF-milk and control-milk fed pigs, indicating that consumption of rhLF-milk did not change cytokine signaling in the intestines. Overall favorable changes in systemic health and GI villi architecture were observed; indicating that consumption of rhLF-milk has the potential to induce positive changes in the GI tract.