I'm interested in PRP for hair loss. (52yo, female.) A friend mentioned that her dr said that PRP is unsuitable for people with autoimmune issues because (a) an autoimmune issue means that your body produces antibodies to your own cells, and (b) PRP injections contains a high concentration of those antibodies. But my understanding is that PRP is often used for autoimmune-related issues -- e.g., alopecia areata, and also for joints damaged by rheumatoid arthritis, etc. Is her doctor correct?