Peptides and the Immune System – Peptides are molecules containing two to tens of amino acids linked through peptide bonds. Short-chain peptides, with fewer linkages, are long known in the pet food industry as palatability enhancers. But their potential on the immune system is still being studied.
Action of peptides in the Immune System
In the immune system there are two types of response, the innate immune response, the first line of defense that is fast, but non-specific and without memory. Then there is also the acquired immune response, which is a slower response, but specific and with memory. It ensures that the individual is protected against eventual re-exposure to the same pathogen.
Within the acquired immune system we have the MHC II process (major histocompatibility complex II). It is the process responsible for antigen apprehension and presentation to helper T cells.
To activate this immune response, protein antigens and short-chain peptides must be converted and bound to the MHC, forming the MHC-peptide complex. This complex behaves as a link for specific antigen receptors, found in the T lymphocyte. It learns and encodes the antigen, expressing itself in APCs (antigen presenting cells), such as macrophages and dendritic cells.
These APCs, in turn, present antigens to helper T cells through CD4+ receptors so that they defend the organism by phagocytizing the antigen and producing antibodies.
In the MOTHES study, T (1994) investigated whether the inclusion of peptides in the diet could exert a direct effect on the expression of MHC-peptide binding. This research suggested that peptides included in the diet can positively regulate the presentation of antigens by APCs, increasing the immune stimulus on lymphocytes.
What are Peptides in Immunology?
The immune system destroys bacteria and viruses, but it also attacks other substances such as nanoparticles that are introduced to deliver drugs or devices such as pacemakers. Now, a team of researchers from the University of Pennsylvania (USA) has created a synthetic peptide capable of deceiving defenses and acting as a passport for therapeutic substances and devices.
What Protein Helps with Immune System Defense?
The immune system destroys bacteria and viruses, but it also attacks other substances such as nanoparticles that are introduced to deliver drugs or devices such as pacemakers. Now, a team of researchers from the University of Pennsylvania (USA) has created a synthetic peptide capable of deceiving defenses and acting as a passport for therapeutic substances and devices. After chemically synthesizing the peptide, the scientists attached it to conventional nanoparticles that introduced into a mouse model. The results of the research, led by Professor Dennis Discher, have been published this week in Science.
A team of scientists from the School of Engineering and Applied Science at the University of Pennsylvania (USA) has developed a synthetic peptide that allows substances to be introduced into the body without being detected and attacked by the immune system.
After chemically synthesizing the peptide, the researchers attached it to conventional nanoparticles that they introduced into a mouse model. The results of the research, led by Professor Dennis Discher, have been published this week in Science.
Diego Pantano, one of the authors of the work, explains to SINC that “this peptide will have multiple applications, among others it advances in the supply of drugs for the treatment of tumors and the use of nanoparticles to improve biomedical visualization. In general, any application that involves invisibility to the immune system will be able to benefit from it”, he underlines.
The immune system exists to destroy intruders in the body, such as bacteria and viruses. But it attacks other therapeutic elements in the same way. “From the perspective of the body, a spearhead from 1,000 years ago and a pacemaker are perceived in the same way: as an invader. With our work we seek that therapeutic devices, sutures or nanoparticles for drug delivery do not cause an inflammatory response by the immune system.
Antimicrobial Peptides Function
Macrophages, a fundamental part of the immune system, should not confuse foreign bodies with cells from the body itself. For this, the cells themselves have markers that inform these macrophages that they should not ‘eat’ them.
“Our work is the first example of a molecule that inhibits the attack of the immune system. This peptide fulfills the same role as the markers mentioned above and therefore. By being grafted onto materials foreign to our body, it prevents the immune system from quickly eliminating them. It allows them to reach the desired destination”, explains Pantano.