Lecture 20 11/6/23 Flashcards
What is immunodeficiency?
-state in which the immune system’s ability to fight infectious disease is either compromised or absent
What are the characteristics of primary immunodeficiencies?
-defect arises from problem with immune system
-inherited genetic diseases
-common in newborns/young animals
What are the characteristics of secondary immunodeficiencies?
-secondary to a known cause
-can include complications from viral disease, cancer, nutrition, and toxins
What clinical conditions can indicate immunodeficiency?
-recurrent infections w/ history in bloodline of primary immune deficiency
-2+ episodes of pneumonia in one year
-opportunistic infections
-multiple infection sites
-recurrent skin/organ abscesses
-single episode of meningitis/osteomyelitis
-2+ months on antibiotics with little/no affect
What are the characteristics of bovine leukocyte adhesion deficiency?
-genetic mutation resulting in nonfunctional leukocyte integrin
-increase in circulating neutrophils due to bacterial stimuli
-few/no neutrophils in tissues
What are the characteristics of Severe Combined Immunodeficiency?
-congenital equine immunodeficiency
-autosomal recessive/heritable
-no functional T or B cells
-animal becomes agammaglobulinemic
-die from overwhelming infection
What are the consequences of a lack of B and T cells?
-no adaptive immune cells
-more viral/intracellular pathogens
What can be seen on necropsy with SCID?
-spleens lack germinal centers and periarteriolar lymphoid sheaths
-lymph nodes lack lymphoid follicles and germinal centers with few cells in the paracortex
What causes SCID?
-lack an enzyme that rejoins DNA after it has been cut
-leads to un-repaired DNA and apoptosis of the lymphocytes
What are the diagnostics for SCID?
-flow cytometry
-measure IgG, IgE, IgA, and IgM levels
-measure/quantify cytokines
-molecular diagnostics
Why is DNA testing important with SCID?
to identify carriers and try to prevent SCID foals
What is the effect of stress on the immune system?
-weakens response
-decreases body’s lymphocytes
How does vitamin A deficiency affect the immune system?
reduced:
-lymphocyte proliferation
-NK cell activity
-cytokine production
-immunoglobulin production
What is the effect of vitamin E?
major antioxidant in cell membranes
What is the effect of vitamin D on the immune system?
receptor for vitamin D is present on most immune cells and is good for the immune cells
