Gavin Kane has done a bit of research on IL-15. He wrote an article on it a while ago:
Interleukin-15
By Gavin Kane
A relatively new and exciting product has once again hit the underground scene with promises of 200+ pounds of muscle in 2 weeks, blah, blah; yeah you know the same old hype and promises. Then there is the, “I have a friend who knows a guy who trained a guy who took it and put on 28lbs in 4 weeks and got leaner”, yeah right. So here we go again, another promise of the Holy Grail, the big one.
So I shall dig deeper into this new and exciting, revolutionary, promising new drug to expose the myth, the hype and hopefully the truth. I will start with an explanation, what exactly is this stuff? IL-15 is a hormone belonging to a class of compounds referred to as pro-inflammatory cytokines. It is naturally produced in the human body but has been isolated and synthetically manufactured. Recombinant Human KGF-1(FGF-7) produced in E.Coli is a single, non-glycosylated, polypeptide chain containing 164 amino acids and having a molecular mass of 18995 Dalton. This makes it the second longest peptide chain in use today, with gh being the longest at 191 aminos. Here is the sequence:
MNWVNVISDL KKIEDLIQSM HIDATLYTES DVHPSCKVTAMKCFLLELQV ISHESGDTDI HDTVENLIIL ANNILSSNGNITESGCKECE ELEEKNIKEF LQSFVHIVQM FINTS
There have been numerous studies that have peaked the interest of research scientists and bodybuilders alike. Most of these studies were performed on rats as human trials have not yet been approved. What is of interest is the increase in myosin contractile protein content, up to a 5x increase upon administration of IL-15. What this means to you is the possibility of skeletal muscle tissue increases 5x faster than without administration of this peptide.
Another recent study looked at the increase in myoblasts, the cells that form into new adult muscle cells, also known as hyperplasia. They also looked to see if there were any increases in cell proliferation and differentiation. Of interest is that IGF levels had to be lowered to increase proliferation, meaning that IGF and IL-15 could be counter acting. Because both peptides perform similar functions, they may actually be competing, with IGF having more pronounced and stronger effects.
While the proliferation of cells does not seem to be prominent unless IGF levels are already low, such as in severe wasting syndrome, what is of interest in this product and noted in all studies is the incredible anti-catabolic effects by reducing protein turnover rates. However, this has only appeared to be true in patients that were once again suffering from severe wasting syndrome such as AIDS or cancer. There was no noticeable change in healthy adults.
In another study from 2001, healthy rats were given 100mcg/kg of IL-15 to study protein turnover, yet no noticeable change was noted. Something of interest did happen in the rats however, huge decreases in white adipose tissue, up to 33% reductions. So while this peptide may not deliver the incredible increases in new muscle cells, it may show promise as an incredible fat loss product while dieting for shows.
This product is headed and being heralded as the next replacement for growth hormone therapy in patients with severe catabolic wasting syndrome. Patients in advanced stages of AIDS, cancer, and burn victims will benefit most from this product. It appears to have incredible anti-catabolic effects and can possibly prevent further tissue damage from wasting by producing new cells. The problem is this will only happen in IGF deficient cells, such as those damaged from a virus.
So what promise does this product hold for bodybuilders? Not much and certainly not at the current cost. I assume part of the mystique of this product and hype is that is it hard to get a hold of, the price is insane, and there are rumors of the upper echelon using it. There is one rumor I can squash right now, no one on the current bodybuilding circuit is currently using this product, not just from lack of availability (you can get anything you want if you have enough money), but from lack of research, lack of real world results, and better products proven to work already available. The average cost of this product is $3550 per 1mg.
IGF-1 LR3 receptor grade can be had for as low as $200 per 1mg, so if it is competing with IGF at cell receptors and you are not deficient, why risk the cost when there are no proven benefits. As much of a rogue peptide user as I am, this is one product that currently has no interest for me.
