Highlights of Immune System

Topic Outline Overview of the Immune System

1st and 2nd lines of Defense

The Immune System B cells The antibody & antibody diversity Vaccinations Breast Feeding Diagnostic applications T cells Allergies

Lines of Defense Physical and

Chemical

Immune system3rd line

1st and 2nd lines

First line of defense

Second line of defense Inflammation Phagocytic cells complement

3rd line of defense“The Immune System”

Summary Lines of Defense

INNATEACQUIRED

Immune System

B cells

T cells

Lymph nodes are contain high concentrations lymphocytes

Let’s look more closely at the B lymphocytes

B Cell: humoral or antibody mediated immunity

ANTIBODIES=IMMUNOGLOBULINS

Humoral Immunity

Matures in bone marrow Moves to lymph nodes (& other locations) Secretes antibodies “as plasma cell” Also creates “memory” B cells

B-lymphocyte

CLONAL SELECTION

Different classes of immunoglobulins or antibodies

IgM

IgG

IgA

IgDIgE

Antibody Diversity

Antibody genes are composed of segments

V J C

Somatic Recombination

http://www.bio.davidson.edu/courses/Immunology/Flash/somaticrecomb.html

How are vaccinations related to immunity?

Active and Passive

Active Vaccinations: Antibody Production

Memory Cells!

Immune Benefits of Breast Feeding

IgA’s

The next part gets tricky

Onto T Cells

All T cells require cell to cell contact

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter24/animation__cytotoxic_t-cell_activity_against_target_cells__quiz_2_.html

CD8+CD4+

MHC=major histocompatibility complex: gene found on chromosome 6

Tissue Transplantation MHC proteins differ between individuals

Helper T Cell and MHC II

Antigen presentation

Cytotoxic T Cell and MHC I

Antigen presentation

CD8+ cell

Cytotoxic T cell= CD8+

B lymphocytes source of

antibodiesOverview of T lymphocytes

Cancer cell being attacked by cytotoxic T cells

After release of perforin

Allergies

B cell also directly stimulated

IgE