Immune System

briefly description of effector mechanism

A) Macrophages


1 - Killing pathogens;
 --> Phagocytosis & Complement
phagocytosis ; engulfing and degradation / digestionb
of fragments of tissues / material

Complement activation --> Classical ( AB-Ag complex formation )
                                    --> Alternative ( component of complement binds to pathogen surface;
                                          mark for destruction
 - main component = C3
  * C3 activation;
 i) recruit inflammatory cells
ii) opsonisation of pathogens
iii) killing of pathogens

2 - Cytokine induction;
 --> toll like receptors; IL -1 , TNF } activation of cells of
                                    Interferons  } adaptive immune response

3) Ag presentation
 --> 2 types of MHC
* Class I
- viruses / intracell bact
- express on all cells

* Class II
- extracell bact / opsonised bact
- express on Ag presenting cells only

MHC- Ag complex ; v.stable, bind with high affinity

** AB - antibody
     Ag - antigen
     MHC - major histocompatability complex