Elimination of Extracellular Microorganisms

Hello everyone,

Today the topic which I would like to share with you is one the strategy to Eliminate Extracellular Microorganisms

Extracellular bacterial pathogens do not invade cells and proliferate instead in the extracellular environment which is enriched with body fluids.  Some of extracellular bacteria even don’t penetrate body tissues (e.g. V. cholerae) but adhere to epithelial surfaces and cause disease by secreting potent toxins.Although bacteria such as E. coli and P. aeruginosa are termed noninvasive, they frequently spread rapidly to various tissues once they gain access to the body.  Extracellular bacteria do not have the capacity to survive the intracellular environment or to induce their own uptake by most host cells.

When there is a infection,  B Cell matures into plasma cell which secretes antibodies

At first time of infection there is no Antibodies in blood and levels do not increase until 7-10 days afterwards. This is called Primary response.

On subsequent exposure to same Microorganisms the level of antibodies begins to increase within 24 hrs and reaches high level which is sustained Secondary response.

Antibodies recognize structures on surface of bacteria. Binding of antibody to microorganisms activate two effector mechanisms to eliminate microorganisms.

• Activation of Complement system  bacterial lysis
• Phagocytosis by neutrophils and macrophages with intracellular killing.

with love 

-Dixy