Lecture 3+4: Cells and tissues of the immune system Flashcards
Polycythemia
Too many RBC’s
Thrombocytosis
Too many platelets
Leukocytosis
Too many WBC
Neutrophilia
Too many neutrophils
Lymphocytosis
Too many lymphocytes
Eosinophilia
Too many eosinophils
Basophilia
Too many basophils
Anemia
Too few RBC’s
Thrombocytopenia
Too few platelets
Leukopenia
Too few WBC
Neutropenia
Too few neutrophils
Lymphopenia
Too few lymphocytes
Hematopoiesis
Blood cell development
Where do immune cells come from
Starts in utero in the yolk sac in the primitive phase then transitions and becomes the definitive stage in the embryo proper
Where do all immune cells derive from
Common multipotent hematopoietic stem cell
What cells make up the myeloid lineage
Eosinophils, basophils, mast cells, monocytes/macrophages, neutrophils, dendritic cells
What cells make up the lymphoid lineage
B and T cells, NK cells
What cell type has longest lifespan
Memory B cells
What cell type has the shortest lifespain
Neutrophils
What are the histological characteristics of a lymphocyte
Large, round nucleus, heterochromatic, thin rim of cytoplasm
What lymphocyte does humoral immunity
B cells
What lymphocyte does cellular immunity
T cells
What are the sources of lymphocytes
Yolk sac—> fetal liver—> bone marrow
What are the primary lymphoid organs
Bursa of Fabricius (birds only), thymus, bone marrow, Peyer’s patches
What a are the secondary lymphoid organ
Lymph nodes, spleen, bone marrow, peyer’s patches
What is the bursa of fabricius
Found only in birds, consists of lymphocytes within epithelial tissue, antibody forming lymphocytes
Where is the thymus located
Mediastinum
What type of cells are located in the outer cortex of thymus
Immature lymphocytes
What type of cells are located in inner medulla
Mature lymphocytes
What is the function of Hassal’s corpuscles
Produce cytokines
How do we further identify T and B cell subtypes
With CD or cluster of differentiation molecules
What CD molecule does Tc bind
CD8
What CD molecule does Th bind
CD4
Why is it important to know the T and B cell subtypes
Lymphocyte phenotyping
What is the primary site of hematopoiesis in adults
Bone marrow
Bone marrow
Hematopoiesis, B cell maturation, primary lymphoid organ
Pancytopenia
Bone marrow wiped out so decrease in all cell types
Why is a bone marrow biopsy especially important in horses
Only way to diagnose immunocompromised horses because they don’t release reticulocytes
What is Peyer’s patches
Mucosa associated lymphoid tissue, common mucosal system
What type of Peyer’s patch do ruminants, pigs, horses and cows have and what is it like
Large ideal peyer’s patch
Primary lymphoid organ
What type of peyer’s patch is present in rabbits and rodents
Small, ileal peyer’s patch
Secondary lymphoid organ
What is located in the cortex of lymph nodes
Primary follicles, B cells
What is located in the paracortex of the lymph nodes
T cells
What is located in the medulla of the lymph node
Plasma cells
High endothelial venules
Allow passage of lymphocytes
What organ is a major site of antibody production
Spleen
What is the function of the white pulp of spleen
Lymphoid tissue, contains B cells and PALS
Describe the steps in extrasvastion
- Tethering of leukocyte loosely via E-selection and CD15
- Triggering- begin to cease roll
3, Latching- firm attachment to ICAM - Diapedesis- leukocyte moves between endothelial cells and cytokines and chemokines direct cell
What is a monocyte called in tissues
Macrophage
What is the name of macrophages in the brain
Microglia
what is the name of macrophages in the liver
Kuppfer cells
What is the name of macrophages in the lungs
Pulmonary interstitial macrophages (PIMS)
What are the two main functions of macrophages
Phagocytosis and antigen presentation
Neutrophils
Segmented, front line innate immune defense, short lifespan
What are immature neutrophils called
Bands
What are some functions of neutrophils
Degranulation, phagocytosis, oxidative burst and neutrophil extracellular traps
What is neutrophil extracellular trap
Neutrophil will release DNA that acts as a trap for bacteria to keep it from replicating
In what cases would eosinophils be elevated
Worms, wheezes and weird disease
What do the granules in eosinophils contain
Major basic protein, eosinophilic perioxidase, eosinophilic cationic protein, eosinophilic derived neurotoxin
What is multisystemic eosinophilic epitheliotrophic disease (MEED)
Overproduction of eosinophils resulting in skin and GI lesions
What do mast cells do
Release histamine as a result of allergic reaction
What do basophils play a role in
Allergic reactions
What is the main function of dendritic cells
Present antigens to adaptive immune system
What is one common veterinary procedure in which dendritic cells play a role=
Vaccines
