Bacteria immune response

Live vaccines are normally weakened strains that do not cause diseases in the host, but stiU can stimulate the immune response. A typical example is the poho vaccine. The weakening of microorganisms or attenuation of the vims or bacteria can be accompHshed by passage through different substrates and/or at different temperatures. Modem genetic engineering techniques can also be used to attenuate a vims or bacterium. 

Dead or live bacteria may be effective to stimulate inflammatory reactions of phagocytic cells against tumor cells. The best-characterized treatment is the use of Bacillus Calmette Guerin (BCG) in the case of bladder cancer where activation of the immune response is capable of controlling tumor growth. 

The science of immunology not only encompasses the body s immune responses to bacteria and viruses but is extensively involved in tumour recognition and subsequent rejection the rejection of transplanted organs and tissues the elimination of parasites ftom the body allergies and autoimmunity (the condition when the body mounts a reachon agairrst its own tissues). 

The role of an immune response to intestinal bacteria in the development of UC may not be as strong a contributing factor as it is in CD. The potential role of environmental factors in the development of UC implies that the immune response is directed against an unknown antigen. The findings that development and severity of UC are reduced in patients who smoke, or in those with appendectomies, may support the theory that these factors may somehow modify either the genetic component or phenotypic response to immunologic stimuli.11,13... 

Multiple factors play a role in the development of AOM. Viral infection of the nasopharynx impairs eustachian tube function and causes mucosal inflammation, impairing mucociliary clearance and promoting bacterial proliferation and infection. Children are predisposed to AOM because their eustachian tubes are shorter, more flaccid, and more horizontal than adults, which make them less functional for drainage and protection of the middle ear from bacterial entry. Clinical signs and symptoms of AOM are the result of host immune response and damage to cells caused by inflammatory mediators such as tumor necrosis factor and interleukins that are released from bacteria.4... 

Probiotics Dietary supplements containing potentially beneficial bacteria that promote health by stimulating optimal mucosal immune responses. 

Returning to bacteria, PC also appears to play a role in infection of humans by pathogenic strains/species by allowing colonization and invasiveness due to interaction with appropriate receptors on host endothelial cells (reviewed by Harnett and Harnett, 1999). This may act as a double-edged sword, however, as the PC on the surface of the bacteria can be targeted by both the innate and adaptive immune responses and indeed such responses appear to play a role in the control of H. influenzae and S. pneumoniae, respectively, in humans (reviewed by Harnett and Harnett, 1999). 

Macpherson A.J., Geuking M.B. and McCoy K.D. (2005). Immune responses that adapt the intestinal mucosa to commensal intestinal bacteria . Immunology, 115, 153-163. 

Therefore, the unresolved question remains of whether chronic, recurring inflammation is the result of a persistent infection with a specific pathogen, an exaggerated exposure to resident normal luminal bacteria products because of increased intestinal permeability or alteration of mucus composition, or an abnormally aggressive immune response to luminal components. 

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