Hi Bhagya,

Its a matter of nature. Fortunately our system is the most sane machinery among all the chaos. The immune system maintains its own record of "naughty and nice" microbes since the existence of humankind. Our innate microflora is essential for the well being of the physical system and the immune system has realized it over thousands of years. Immune system takes a chance with any new microbe. Slashes it if harmful and adopts it if beneficial. One can only say that our innate microflora have proved their loyalty to its physical system (like symbiosis) over a long time. Evolution by itself is an outcome of immunity development. Hope you found this helpful

Dear Bhagya, this is really true, while barriers remain integral and adaptive immune system do not "see" the pathogens. The integrity is supported by complex coordinated functioning of phisical and chemical barriers, epithelial cells, intercellular matrix and components of innate and adaptive immunity. This explains, how we can exist without any signs of septic shock, having kilogramms of LPS in intestinal tract. When integrity is failed, we see different kinds of infectional pathologies and subsequent immune reactions, even in response to commensal microbiota, capable to become very dangerous after alteration of immune status. You can see this in patients with AIDS, after irradiation and treatment with cytostatic drugs. Sepsis and fungal infections are becoming a real threat to the life.

Do check out the following article http://www.sciencedaily.com/releases/2007/01/070109142008.htm

symbiotic microflora of human body turn into pathogenic when person become immunocompetent. This nature of microflora indicates that there exist some kind of immune function towards symbiotic microflora.

Thank u everybody..............................

M just thinking that of-course we born with some normal micro-flora but,they are of two types residents and transients right........does that symbiosis works with transients also?.......i feel our body should recognise transients which will become opportunistic microbes some time...............i don't know my thinking is correct or not, but i got this question my mind .

Hi Bhagya,

Please refer to the following publication. This will help you understand the minute details of how certain T cell subsets provide protection to gut microbiota. http://www.nature.com/nature/journal/v497/n7448/full/nature12079.html

Dear sir......................Simarjot Pabla

Thank u so much......it helped me.