1. HIV & the Immune System

2. The Immune System Is like a screen in a window….it keeps the bugs out. The body’s defense against illness. It keeps the body healthy and prevents infections. It is made of cells, tissues and organs that work together to protect the body.

3. Parts Of The Immune System White Blood cells (CD4+ T helper cells) Lymph Thymus Spleen Bone marrow Antibodies

4. An Immune Response When a foreign substance (antigen) enters our bodies, our immune system goes those a series of steps to fight the foreign substance and protect our bodies. The antigen is like a “critter” that can cause an illness  Virus, fungi, bacteria, protozoa (like an insect)

5. Our Immune response Some of the “players” include... B-cell CD8+ T-cell Antigen Presenting cells - Cells of the immune system that bring intruders to CD4+ T cells. (e.g. macrophages and dendritic cells ) CD4+ T-cells (also may be called “T4 helper cells”, “T4 cells”, or less accurately “T-cells”. CD4+ T cells are the conductors of the immune system. CD4+T-cell CD8+ T-cells - Some CD8+ T cells, when ordered by CD4+ cells will seek out and destroy infected cells. B cells - During an immune response B-cells make antibodies. Antibodies - Antibodies are made by B-cells, they attach to “critters”, marking them for destruction by the immune system. Antibodies are specific to the “critter” (bacteria, virus, or other harmful toxins).

6. HIV and the Immune System HIV primarily attacks the CD4+ T cells  The CD4+ cells are the conductor of the immune system  CD4+ cells are changed into “HIV” producing cells.  Without a healthy conductor the immune system can’t work properly. Let’s talk about how HIV changes the CD4+ cells……