Immune System Flashcards
T-lymphocyte
(Intestinal Epithelium)
Identify the following:
B-lymphocyte
Plasma Cell
Reticular Cell
Lymphoblast
Identify the following:
Lymphoblast
Lymphoblast in Mitosis
Identify the following:
Lymphocyte
Much smaller than a lymphoblast
Located in the Mantle Zone
What unique feature can be seen in this simple columnar epithelium?
M-cells:
- Pocket containing lymphatic cells
- B-cells
- T-cells
- Macrophages
- Dendritic cells
Located in the epithelium
Identify a lymphatic nodule in this Rabbit secum
Identify a lymphatic vessel. What is this typically composed of?
Carries filtered lymph away from diffuse lymphatic tissue to lymph nodes
ex. Tonsils
What is going on in this stratified squamous epithelium?
White blood cells are migrating into the epithelium
What is this cell and how can you tell?
Plasma cell:
- Clock face
- Pink Cytoplasm
Identify the outlined zones in the lymphatic nodule
Germinal center:
- Has immature proliferating lymphocytes
- B-lymphoblasts (in this case)
- Lighter staining
- B-lymphoblasts are euchromatic
Mantle Zone:
- Filled with b-lymphocytes
- These are in a period of inactivity
Identify the circled cell:
Tingible Body Macrophage:
- Phagocytize and digest unwated T-cells
- Consist of a larger, irregular shaped nucleus
- Found in cortico-medullary junction
What is so special about the circled blood vessel?
HEV
These are specialized blood vessels
- Only found in the medulla of the thymus
The epithelial cells surrounding the blood vessel are rounder and not as flat
This is the location where mature T-cells can easily pass through the epithelium and enter the bloodstream.
Identify a thymic corpuscle.
Where are they found in the thymus?
Found in the medulla of the thymus
What is going on with the T-cell circled?
Mitotic Division
How would you identify the T-lymphocytes in the cortex?
Small, circular cells
Darkly stained nucleus
Heterochromatic
Identify the epithelial cells surrounding the blood vessel that is part of the blood/brain barrier.
Blood-Thymus Barrier=
Epithelioreticular cells + Endothelial cells + Pericytes
Identify the following cells in the Thymus.
Nursing cells in the Thymus
They support T-cells
Identify a Thymic Lobule
Identify the following circled cells:
Plasma cell: Clock-face appearance
T-lymphocyte: Capable of migrating into epithelium
Innate Immune Response
Goal = immediately prevent the spread and movement of foreign pathogens throughout the body
- First line of defense against invading pathogens
- Very quick response time
- first critical hours after exposure to a new pathogen
- Needed until the adaptive immune response is ready
Components:
- Epithelial surfaces
- Only one not found in the bloodstream
Phagocytitic cells:
- Macrophages
- Dendritic cells
- Natural killer cells
- Complement systems (not cells)
The nature of the immune response depends on the type of infection
Adaptive Immune Response
- 24 hours post infection
- Works together with the innate immune response
Adaptive Immune Response Requires:
T-lymphocytes
B-lymphocytes
Plasma cells
- Activated b-lymphocytes
Antigen presenting cells
The Innate Immune Response is dependent on
Epithelial Surfaces (1)
- Prevent the entry of pathogens
- Nose & trachea
- Pathogens stick to the mucous
- Skin
Simple Epithelium
Innate Immune Response
- Large number of immune cells directly under the the basement membrane
- Only have basement membrane + 1 layer of cells
- Conditions allow for pathogens to penetrate with ease
- T-lyphocytes
- Plasma cells (activated B-lymphocytes)
Reason behind why there is a vast number of immune cells ready to mount a response to a possible infection
Stratified Cornified Epithelium
(Skin)
Innate Immune Response
Close contact with external environment
Physical barrier to entry
“Cornified” referring to the most superficial layer of cells lacking nuclei and having a squamous shape
- Filled with keratin protein
