The size of transfer factors and their absorption following oral administration

Transfer factors, growth hormones, and other important constituents of colostrum are swallowed by infants and absorbed intact via the digestive system. However, the digestive systems of newborns are not complete, creating a window of opportunity for getting these things in.

Of import is whether the short-chains of amino acids that comprise transfer factors are absorbed into the body intact following oral administration or are broken down during digestion in the stomach and intestines. The technological advances that have allowed these immune boosters to be sold in powdered form and taken orally are only valuable if the end product gets into the body and becomes bioavailable.

As discussed, transfer factors appear to be, primarily, chains of amino acids. Amino acids are strung together into short chains (peptides) and long chains (proteins). During digestion, proteins are broken down into amino acids, dipeptides (a pair of amino acids) and tripeptides (three amino acids together) by enzymes called proteases and peptidases. While two or three amino acids might not sound like a lot, some important peptides in the body are, in fact, that short. Glutathione, an antioxidant, and thyrotropin releasing hormone, a hormone central to thyroid functioning, are only three amino acids long.

In some people — lots of people, in fact — gaps between cells lining the gastrointestinal tract are too large, allowing proteins, bacteria, toxins and other large molecules to get in. The problem is called “leaky gut”. As such, these molecules get into the body and are then attacked by the immune system. Food allergies, such as peanut allergies, can result. While these gaps could help absorption of important meds, the constant presence of these gaps causes lots of problems.

Researchers are currently working on ways to make the gut leaky temporarily so that supplements and drugs can be absorbed more fully.

In 2000, Kirkpartrick wrote that, “To date, neither the primary structures nor the mechanisms of action of transfer factors have been identified. However, recent studies have shown that transfer factors can be purified to a high degree of homogeneity and that the purified transfer factors are proteinaceous and immunologically specific.”

The researcher and his colleagues identified a conserved amino acid sequence in transfer factors, meaning that all transfer factors seem to contain this particular strand of amino acids plus whatever it is that makes each one specific to a pathogen. Interestingly, administering this conserved sequence to mice receiving complete transfer factor molecules blocked the effects of the complete transfer factors, a finding similar to how some drugs shaped like neurotransmitters prevent neurotransmitters from activating their target receptors in the brain. Kirkpatrick believes that this conserved sequence represents the portion of the transfer factor molecule that binds to receptors on white blood cells. Once bound, the remaining portion of the molecule conveys immunity in some way.

The conserved sequence itself is longer than three amino acids in length. In fact, it appears to be 10 amino acids in length. The paper does not examine the length of the active components of the transfer factor molecules. Transfer factors are thought to have a molecular weight of about 5000 Daltons (Da). For reference, Tryptophan is the heaviest individual amino acid at 204.22 Da.

Oral transfer factors seem to work, which provides compelling anecdotal evidence that they do get absorbed and become bioavailable. Indeed, the flu-like symptoms that often result from their use clearly indicate that enough of the supplement gets in to activate the immune system. How they are absorbed, how much is absorbed, and what percentage of the doses become bioavailable are not known – at least not to the author of this paper. If you have insight and would be willing to share, please send the information to aaron@learnaboutTF.com.