Hypersensitivities 1 & 2 Flashcards
Two stages of hypersensitivity type 1
- sensitization: antigen encountered; symptoms not experienced
-effect stage: repeat exposure to antigen; body recognizes antigen; results in response w/ typical allergic rxn response
Effector of type i hypersensitivity
- IgE
- mast cells, basophils, eosinophils
- IgE coated mast cell degranulation and inflammation
Effector of type ii
- IgG, IgM
-nk cells and complement destroy antibody coated cells
Effector type 3
- IgG
- complement activation and neutrophil degranulation
Effector type 4
- No antibodies
- memory t cells and macrophages
mediators released by mast cell and basophil degranulation
- histamine: makes everything “angry” ( red, hot, swollen) & increases mucus prod.
- prostaglandins: smooth muscle contraction and mucus secretion
- leukotrienes: bronchal spasms
Skin tests for type i hypersensitivity
- blood test: ELISA for allergen specific IgE antibodies
- skin test: diluted extracts from allergens injected ID. Rxns may//may not happen within 30 mins
Major organ affected by anaphylactic shock in dogs
Liver
Name the 3 transfusion rxns that are type 2 rxns
- ABO Blood groups system
- hemolytic disease of newborn
- Rh blood group system
Summarize pathogenesis of Neonatal Isoerythrolysis
Mom prod. Antibodies against rbc factor (lacks originally)
Foal inherits rbc factor from dad
Mom’s colostrum has antibodies against factor which tag foal’s rbc and destroys them
Diagnosis of neonatal isoerythrolysis
Mare Showing anti-rbc antibodies in colostrum/serum
Similarity & difference between foal and mare rbc
- similarities: hemoglobin structurally identical
- diff: newborn= higher affinity for O2 than mom
How can mares be exposed to rbc factor
- colostrum
- transfusion
What type of hypersensitivity is neonatal isoerythrolysis
2
Pemphigus
Autoimmune disease where skin attacks connections between its own skin cells
