W11

What are the 4 steps in cell-mediated immunity (T-lymphocytes)?

1. Antigen presentation

   • An infected cell or an APC present an exogenous (viral

     antigen or non self-antigen) on an MHC I

2. Activation of T cells and Co-stimulation → Proliferation

   • Naive Tc come into contact with APCs in the lymphatic tissues or at the site

     of infection. The CD8 receptors recognizes the MHC, and the antigen binds

     to the antigen binding clef.

3. Fxn aka killing

   • perforin → granzymes and peroxides

4. Formation of memory T cells

What cell kills cell that don’t present an MHC 1 or shows ADCC?

NK

Examples of an Attenuated vaccine?

• Measles

• Mumps

• Chickenpox

Examples of an inactive vaccine?

• Influenza

• Rabies

Examples of a subunit vaccine?

• Hep B

Autoimmune v immune deficiency

1. Autoimmune diseases:

   • Type 1 diabetes, lupus, graves’ disease, myasthenia gravis, MS, and others → attacks self

2. Immune deficiency:

   • Can result from genetic defect, infection, environmental factors, or treatment → bubble boy

What are the 5 steps of Type 1 hypersensitivity?

1. Initial exposure to allergen → B cell production of IgE

2. Sensitization → attachment of Fc region of IgE to histamine producing cells

3. Subsequent exposure to allergen

4. Degranulation

   • The binding of the allergen triggers the release of histamine from mast cells and basophils

5. Symptoms of Allergic Reaction

What Allergic Reaction symptoms result from basophils and are the systemic or local?

Anaphylaxis and systemic

What Allergic Reaction symptoms result from mast cells and are the systemic or local?

• Hay fever (sneezing, runny nose, itchy eyes) → mucus production

• Hives (wheal and flare)

• Asthma (bronchoconstriction)

• local

What is the Treatment & prevention options for type 1 hypersensitivity?

Treatment

• Hive & Hay fever → antihistamines

  Asthma → antihistamines are ineffective but steroids work

  Anaphylaxis → Epi-pen & hospital intervention

Prevention

• Desensitization (exposure therapy)

  • Causes immune system to produce IgG instead of IgE. The IgG neutralize the allergen

• Omalizumab or rhuMab (Recombinant humanized Monoclonal antibody)

  • synthetically produce IgG

incompatible bl transfusions and hemolytic disease of the newborn is associated with what type of hypersensitivity?

2

Penicillin allergies are due to what hypersensitivity type?

3

When IgG or IgM form small immune complexes, leading to blood clot formation, this can be linked to conditions like glomerulonephritis and arthritis. This is characteristic of which type of hypersensitivity.

3

Contact dermatitis and leprosy are caused by what, and are associated with which type of hypersensitivity?

caused by…

• Cheap metal (nickel) jewelry

• Poison ivy and oak

4

What hypersensitivity is caused by Cytotoxic T cells destroy infected cells and peak 2-3 days after exposure?

4