I have a few questions in regards to attraction/stimulation in the immune system.
- What attracts leukocytes and antibodies to pathogens in the first place?
- What attracts CD4+ cells to professional antigen-presenting cells (APC)?
- What attracts CD8+ cells to cells with an antigen on a MHC-1 protein?
- What attracts macrophages to pathogens that have been tagged with antibodies?
Is it just a case of everything bumping into each other and if cells (and antibodies??) bump into chemokines and/or cytokines they will be stimulated (and not attracted) to stay around that area moving to an area of a greater concentration of chemokines and/or cytokines?
That said point 1 can occur without chemokines and/or cytokines (in the case of antibodies, they could be taken/administered by the person). While in case of point 3, (I may be wrong here) but chemokines and/or cytokines may not be present in the case of MHC-1?