These cells secrete molecules that kill target cells, principally by punching holes in the target cell membrane. In the disease AIDS, caused by HIV virus, the virus infects and kills for the most part helper T cells. HIV thus indirectly disables the immune system, making the patient vulnerable to future infections. Macrophages are highly phagocytic cells that gobble up pathogens, pieces of wood splinter, debris, dead cells of all sorts, and so on. B lymphocytes - transform to plasma cells to make antibody against antigen Mast Cells , as already described, exist in loose connective tissues, in the tissues surrounding lung airways, and in the tissues surrounding blood vessels.
Mast cells have IgE receptors on their surface.
Histamine and SRS-A cause bronchoconstriction and generalized vasodilation, with the result being difficulty breathing and a drop in blood pressure. With contact dermatitis, this can be treated with corticosteroids or antihistamines which inhibit immune system cell activity and the resulting inflammation and itching. Review Questions 1. The secondary immune response a. is also called the anamnestic response b. produces less antibody than the primary response c. BOTH a and b are true.