Immunology/Hematology Flashcards
What is the normal platelet number per HPF in dogs?
8-15 platelets/HPF (120 - 225K/uL)
*Each platelet = 15,000/ platelets/uL
What is methemoglobin?
A type of hemoglobin that the iron on the heme has been oxidized from ferrous (Fe2+) to ferric (Fe3+)
When there are >30% methemoglobins in the circulation, what does the pulse oximeter usually show? Why?
85% (even if PaO2 is high)
Methemoglobins absorb both wavelengths of light very well.
What are the two type of reticulocytes in cats? Which one can be seen up to 10% in healthy cats?
Aggregate reticulocytes & Punctate reticulocytes
Punctate reticulocytes can be seen in healthy cats
* Aggregate forms are released from the marrow and, after approximately 12 hours, develop into punctate forms that persist in the circulation for 9–20 days.
Where does ferritin exist and what is its function?
Ferritin exists in all cells
It stores iron and acts as a reservoir to prevent excessive intracellular ion causing cell damage.
What is the function of Hepcidin?
It is secreted by hepatocytes and inhibits iron export from enterocytes, macrophages, and hepatocytes.
↑ production during iron overload
What is the function of transferrin?
Transport iron
For Transferrin and Ferritin, which one is positive acute phase protein and which one is negative acute phase protein?
Transferrin: negative acute phase protein
Ferritin: positive acute phase protein
What is the lifespan for canine and feline RBCs?
Dog: 120 days
Cat: 80 days
What is the lifespan of platelets?
5-7 days
What is the lifespan of neutrophils?
< 24 hours
What is the function of haptoglobin?
It binds to free hemoglobin in the circulation
True or False: Hemoglobin has 2 𝜶 globins and 2 𝜷 globins, all of which contains heme molecules.
True
Which iron can bind to oxygen, ferric or ferrous?
Ferrous (Fe2+) can bind to oxygen
Ferric (Fe3+) cannot
What does 2,3-DPG do?
It decreases hemoglobin affinity to oxygen.
What is Heinz bodies?
Damaged hemoglobins (usually from oxidative damage)
What is phosphofructokinase (PFK) deficiency and what is the treatment?
Periodic intravascular hemolysis and hemoglobinuria associated with strenuous exercise or stress-induced hyperventilation causing respiratory alkalosis
Treatment: exercise restriction
What is pyruvate kinase (PK) deficiency?
Decreased ATP availability due to lacking of PK → hemolysis
Moderate to severe macrocytic hypochromic anemia with marked reticulocytosis → myelofibrosis → non- regenerative anemia
- Worse prognosis compared to PFK deficiency
List 10 causes of hemolysis.
1) Primary IMHA
2) Mycoplasma haemofelis infection
3) DIC
4) Splenic neoplasia
5) Hypophosphatemia
6) IV hypotonic fluid bolus
7) Phosphofructokinase deficiency
8) Pyruvate kinase deficiency
9) Uremic-hemolytic syndrome
10) Onion ingestion
11) Zinc, copper toxicity
Which type of hypersensitivity is associated with IMHA?
Type II
Describe neonatal isoerythrolysis.
It happens in kittens - when type B queen mated to a type A male and the kitten is type AB or A.
When kitten is nursed with the queen’s colostrum, the can absorb the antibodies against type A epitope. About 12-24 hours after colostrum ingestion, the antibodies against type A epitope will be in the circulation and attack kitten’s RBCs
What is the equation for corrected reticulocytes?
Corrected reticulocytes = Measured reticulocytes x (PCV/N)
*In dogs, N = 45; in cats, N = 37)
After a BM insult, which cell line decrease will be observed first?
Granulocytes → Neutropenia (5-6 days later)
Thrombocytopenia (8-10 days)
What is the function of hepcidin?
It regulates the iron metabolism and availability.
Increased hepcidin → decreased iron availability
Positive acute phase protein
What is the definitive of RBC regeneration in dogs?
Reticulocytes > 60K/uL
What is the common sequela of Pyruvate kinase (PK) deficiency?
Myelofibrosis
Osteosclerosis
Hemosiderosis-induced hepatic failure or bone marrow failure
Does canine and feline RBC contain mitochondria?
No
What is normal RBC:WBC ratio?
500:1
How to calculate HCT?
HCT = MCV x RBC/10
Name 3 oxidizing agents in the neutrophils
Superoxide (O2−)
Hydrogen peroxide (H2O2)
Hydroxyl ion (OH )
- one of the lysosomal enzymes, myeloperoxidase, catalyzes the reaction between H2O2 and Cl- to form hypochlorite, which is exceedingly bactericidal.
During inflammation, what is the first line to four line defense mechanism of the body.
1) Tissue macrophage
2) Neutrophil Invasion of the Inflamed Area
3) Second Macrophage Invasion Into the Inflamed Tissue
4) Increased Production of Granulocytes and Monocytes by Bone Marrow
How many days does it take for the newly formed granulocytes and monocytes reach the stage of leaving the bone marrow?
3-4 days
What are the 5 factors that are mainly responsible in control of macrophage response (to stimulate BM)?
1) TNF-𝜶
2) IL-1
3) GM-CSF
4) G-CSF
5) M-CSF
Name two cells that can release eosinophil chemotactic factors.
Mast cells
Basophils
Name 4 substances mast cells (and basophils) release during inflammation.
Heparin
Histamine
Bradykinin
Serotonin
Name 4 components of innate immunity.
1) Phagocytosis of bacteria by neutrophils & lymphocytes
2) Stomach acid and digestive enzymes destroy the swallow organisms
3) Skin as a barrier to invaded organisms
4) Certain chemicals in the blood that attach to foreign organisms or toxins and destroy them (e.g. complement complex, lysosome, basic polypeptides, natural killer lymphocytes)
What are the two main types of acquired/adaptive immunity?
Humoral immunity (B cell immunity)
Cell-mediated immunity (T cell immunity)
Fill out the blank.
In normal body, how many percentages of immunoglobulins are IgG?
75%
Name four ways of antibodies destroy antigens directly.
1) Agglutination
2) Precipitation
3) Neutralization
4) Lysis
Write down the classic pathway of complement.
1) antibody attached to antigen - Fc portion binds to C1
2) c5b, C6, C7, C8, C9 form membrane attack complex
3) C3b opsonin for macrophage
Which complement protein cause opsonization of bacteria?
C3b
What is the complement protein compose the membrane attack complex (MAC)?
C5b6789
- MAC inserts itself into lipid bilayers and makes holes on the cell → cell lysis