Immune mediated Deficiency Flashcards
What is an immune deficiency
Impairment in parts, or the function of specific parts, of the immune system that, in having this impairment, causes the animal to be susceptible to infectious disease.
What is a primary immune deficiency
Inherited or congenital, it occurs when there is a mutation in a gene that is associated with the immune response
Clinically apparent in early life
Increased mortality chance (depends on impact of mutation)
Breed associated
RARE
Lack of research
What is a secondary immune deficiency
Not a mutation and they are relatively common,
A healthy older animal, that had a normal immune system, until a physiological or pathological change within the immune system.
Age, chronic disease, infection, therapeutics
What is Canine Leukocyte Adhesion Deficiency (CLAD)
Autosomal recessive disorder
Single nucleotide mis-sense mutation in the beta-2 Integrin gene
Common in Irish Setter
Abnormal blood clotting & Impaired immune system
Prevents white blood cells adhering / eliminating pathogens
Persistent neutrophilia – but what does this show?
Chances of finding in clinic are rare
Immunodiagnostics to look for the mutation from a breeding perspective.
What is Severe Combined Immunodeficiency (SCID)
Dogs and Horses (breed dependant)
Basset Hound
- Mutation for key cytokines (IL-2, 4, 7, 9, 15)
- Leads to immune system failure
Jack Russel Terrier
- Mutation for Lymphocyte formation
- Inhibits immune response
Arabian horse (mostly)
- Mutation impacts T & B cell receptors
- Inhibits somatic mutation to different antigens
- Clinical diagnosis not straightforward
- Pyrexia, respiratory complications, diarrhoea.
What would you do in practice with a suspected immune deficiency
Blood work- response to vaccination, recurrent infection, neutrophilia or lymphopenia
Think about breed susceptibilities
Not very clear
treat symptoms/ effects
4 possible causes of secondary Immune deficency
Age related decline
Specific Infectious disease
Chronic Stress
Malnutrition
4 possible causes of secondary Immune deficency
Age related decline
Specific Infectious disease
Chronic Stress/ Glucocorticoids- supress immune response-> increased infection susceptibilty
Malnutrition
how can age related decline lead to secondary immune deficency
Decline in CD4+ (memory cells)- few naive t cells produced in older age, ratio of CD4+ to CD8+ reduced
Persistent titre of antibodies- for known pathogen is ok, new pathogen impacts the animal
Example of infectious disease that leads to secondary immune deficiency (cats)
FIV
How does malnutrition lead to secondary immune deficiency
Reduced leptin-> reduced T lymphocyte function
4 possible causes of secondary Immune deficency
Age related decline
Specific Infectious disease
Chronic Stress/ Glucocorticoids- supress immune response-> increased infection susceptibility
Malnutrition
