Imunitatea: ce, cum, de ce, in ce fel?

[Alex]

Ce este imunitatea?

Immunity is a biological term that describes a state of having sufficient biological defenses to avoid infection, disease, or other unwanted biological invasion. Immunity involves both specific and non-specific components. The non-specific components act either as barriers or as eliminators of wide range of pathogens irrespective of antigenic specificity. Other components of the immune system adapt themselves to each new disease encountered and are able to generate pathogen-specific immunity.

Adaptive immunity is often sub-divided into two major types depending on how the immunity was introduced. Naturally acquired immunity occurs through contact with a disease causing agent, when the contact was not deliberate, whereas artificially acquired immunity develops only through deliberate actions such as vaccination. Both naturally and artificially acquired immunity can be further subdivided depending on whether immunity is induced in the host or passively transferred from a immune host. Passive immunity is acquired through transfer of antibodies or activated T-cells from an immune host, and is short lived, usually lasts only a few months, whereas active immunity is induced in the host itself by antigen, and lasts much longer, sometimes life-long. The diagram below summarizes these divisions of immunity.

Ok, ne vaccinam, respectam regulile de igiena. Dar cu toate astea se intampla sa ne imbolnavim foarte des, oricat am incerca sa ne ferim. De ce imunitatea nu face fata cateodata? Ce anume o influenteaza, ce anume o activeaza sau reduce raspunsul imunitatii?

Astazi am citit un articol foarte interesant: http://psychologymatters.apa.org/stressimmune.html

In the early 1980s, psychologist Janice Kiecolt-Glaser, PhD, and immunologist Ronald Glaser, PhD, of the Ohio State University College of Medicine, were intrigued by animal studies that linked stress and infection. From 1982 through 1992, these pioneer researchers studied medical students. Among other things, they found that the students\' immunity went down every year under the simple stress of the three-day exam period. Test takers had fewer natural killer cells, which fight tumors and viral infections. They almost stopped producing immunity-boosting gamma interferon and infection-fighting T-cells responded only weakly to test-tube stimulation.

Si atasat, un articol putin mai detaliat.

 

[Bogdan]

Adica, o sa-l trimit pe sefu\' la origini daca ma mai streseaza :clapping:

 

[Alex]

Sau invers: il stresezi si tu pe el, ii scade imunitatea si crapa! :clapping: