Thread: Natural Killer Cells/RBC/Sperm

Hello,

Quick question...

I was studying immunology and came across the natural killer cell. From my understanding, natural killer cells basically kill cells that lack MHC I (found on all nucleated cells and platelets). I guess my question is then why don't natural killer cells kill our own RBCs? What is the marker/surface antigen that prevents RBC destruction?

In addition, I understand that the testes are an immunologically privileged area of the body; however, when sperm enter the female vaginal tract, why aren't natural killer cells activated by the lack of MHC on sperm?

Hope these aren't stupid questions.....maybe I overlooked something totally obvious.

Originally Posted by Can2carib

Hello,

Quick question...

I was studying immunology and came across the natural killer cell. From my understanding, natural killer cells basically kill cells that lack MHC I (found on all nucleated cells and platelets). I guess my question is then why don't natural killer cells kill our own RBCs? What is the marker/surface antigen that prevents RBC destruction?

In addition, I understand that the testes are an immunologically privileged area of the body; however, when sperm enter the female vaginal tract, why aren't natural killer cells activated by the lack of MHC on sperm?

Hope these aren't stupid questions.....maybe I overlooked something totally obvious.

The MHC class 1 molecule has to do with the HLA system.RBCs do not have this system.Also, the antigen which the NK cells attack is not clearly understood nor identified as yet. But in any case the RBCs do not contain this antigen either.

Normally, the testes contain a natural barrier that acts as a protective layer by preventing immune cells from gaining access to sperm within the male reproductive tract. However, the barrier can be broken when testicles are physically injured, after a surgery (biopsy or vasectomy) or after a prostate gland infection. This allows sperm to come into contact with the immune system resulting in the production of the antibodies. If a high number of sperm antibodies come into contact with a man’s sperm, it may be hard for the sperm to fertilize an egg.

WBC's are meant for repelling and fighting external intruding bodies. RBC's are there to take care of the hemoglobin and oxygen transport in human body. And as the name 'Natural killer cells' itself suggests, they kill defected (lacking MHC I) cells only. It's simple.

"Not well understood" and anything not well understood you dont have to learn :P

Means? Could you plz come again?

Good article! Thank you for sharing!

hi, thank you for the explaination.