Patho Lab 4

• Born with it
• Chemical and physical barriers
• non-specific mechanisms
• Non-adaptive mechanisms
• Protection that is always present. Includes phagocytic (cells that eat other cells) macrophages and dendritic cells.

• Exposed to it 
• both adaptive and specific
• Protection that arises by an immune response, including humoral immunity producing antibodies and cellular immunity.

• Innate (natural) (native) immunity 
• Physical barriers: skin, mucous membranes, vomiting, coughing, urination, defecation
• Biochemical barriers: Mucus, perspiration, saliva, tears, cerumen (ear wax), chemicals derived from normal flora, sebum

• Non-specific mechanisms of immunity 
•   -inflamation
• Phagocytosis
• search and destroy

• Cell-mediated
• Antibody-mediated ("humoral")

• cells that consume and present an antigen to the immune system starting the process of producing antibodies to that antigen
• Macrophages, dendritic cells, and some B lymphocytes
• Macrophages attack and engulf the antigen
• antigen is digested and processed 
• then it is displayed on the APCs surface

• They are recruited by advertising of antigens displayed on the APC
• When they see the antigen, they release cytokines and stimulate cell division by autocrine activation
• As they divide they form:
•   -T-memory cells- speed future response
•   -T-helper1 cells- cell mediated immunity
•   -T-helper2 cells- activate antibody-mediated immunity

• Activated by T_helper lymphocytes 
• When activated, release compounds that kill cancerous or virally infected cells
• Apoptosis is preferred for virally infected cells
•   -DNA fragmentation reduces risk of virus re-infection
• Perforin used to trigger cytolysis

Flagging for destruciton

• auto-, allo-, or heterophile cell markers
• Anything causing an immune response, usually foreign material but may be our own tissues.

• phagocyte -dives into puss and dies
• poor antigen presenter

• phagocyte 
• professional antigen presenter

• targeted self antigens
• A failure of tolerance, the immune system reacts to self.

Any disease causing microorganism

• Signaled by macrophage 
• signal T_c and B cells

Target virally infected cells

a specific immunity blood cell

• prominent in secondary immune response
• 75% of plasma antibody
• monomer
• Actively transported across the placenta (maternal-fetal)
• Longest half-life of the immunoglobulins 
•   -Long-term immunity

• cellular communication
• Signaling molecules released by one cell to cause a response in another. Signaling is extremely important in our immune response.

• present in plasma and body secretions
• contains sIgA- secretory component- protects from enzymatic destruction
• Lacrimal glands, salivary glands, and lymphoid tissues in the breasts, bronchi, intestines, and GI tract
• Protects against pathogens that are inhaled, swallowed, or come in contact with external serfaces.

Cells in our bone marrow, thymus, and the lymphatic system of ducts and nodes, spleen, and blood that function to protect us.

Non-reactivity of the immune system, usually refers to "self" but may include foreign tissue in organ transplants.

Molecules released by pathogens and infected tissues to attract cells of the immune system.