Question

Answer the following questions related to immunity.

Describe the differences between cell-mediated immunity and antibody-mediated immunity.

Describe the differences between innate/natural immunity and acquired immunity.

What is the antibody-antigen complex (AB-AG)?

Describe the roles of the T cells and B cells.

Describe one auto-immune disorder (select any autoimmune disorder and describe it).

Answer 1

Cell mediated immunity

• It involves helper and cytotoxic To lymphocytes.
• It provides resistance to Tuberculosis and viral infected cells.
• It is characterized by the release of interleukins.
• It involves granzymes and perforins.
• It involves cytotoxic T lymphocytes attacking virus-infected cells.

Antibody mediated immunity

• It is established by B cells that mature in the bone marrow.
• It involves the production of antibodies.
• It involves plasma cells produced from B-lymphocytes.
• It is activated by a B cell cross-linking process.

2.Natural immunity

• Resistance-Unchanged on repeated infection.
• Specificity-Same for all organisms.
• Cells-Phagocytes, natural killer cells.
• Molecules-Lysozyme, complement, scute phase protein s, IL-1, IFN-alpha and IFN-beta.

Artificial

Resistance-improves with repeated infection.

Specificity-specific for different organisms

Cells-B and T cells.

Molecules-Antibodies and cytokines.

3.It is the cross-linking between antigens and antibodies allowing greater interactions with macrophage FcR to facilitate uptake. Forces involved in Antigen-Antibody interactions are hydrogen bond, electrostatic interactions, hydrophobic interactions and Vsnderwaals interactions.

4 B cells is a type of WBC which originate and mature in the bone marrow, function as part of the adaptive or acquired immune system.

• Function as an antigen-presenting cells
• Make antibodies against antigens
• Form memory B cells after activation by antigen interaction.

T lymphocytes

• A type of WBC which originate in the bone marrow, but mature in the thymus glabd, function in the cell- mediated component of acquired immune response.
• It promote the activity of other immune cells in the acquired immune response.

Multiple sclerosis

It is a chronic, progressive, degeneraive disorder of the CNS characterized by disseminated demyelination of nerve fibers of the brain and spinal cord. MS is characterized by chronic inflammation, demyelination and glioses in the CNS. The common symptoms include motor, sensory, cerebellar and emotional problems.

Diagnosis -MRI for lesions in CNS, visual evoked potential to look for lag in nerve conduction time of eyes, CSF analysis to look for antibodies.