Lymphocytes and Immunity Flashcards
1
Q
What is the normal range for Lymphocytes in dogs?
A
1,000-4,500 / microliter
2
Q
What is the normal range for Lymphocytes in cats?
A
1,500-7,000 / microliter
3
Q
What line of defense are Lymphocytes associated with?
A
3rd line (specific immunity)
4
Q
True or False: Lymphocytes are not capable of phagocytosis
A
true
5
Q
True or False: Lymphocytes are capable of recirculation
A
True
6
Q
What is the life span of Lymphocytes?
A
weeks to months to years
7
Q
What is Lymphocytosis?
A
increase in lymphocytes
8
Q
What are the causes of Lymphocytosis?
A
- epinephrine release (splenic contractions)
- leukemia/neoplasia
- antigenic stimulation
- chronic inflammation
- later stages of resolving infections
- very young animals
9
Q
What types of Leukemia/Neoplasia cause Lymphocytosis?
A
- lymphoma
- lymphosarcoma
10
Q
What is Lymphopenia?
A
decrease in lymphocytes
11
Q
What are causes of Lymphopenia?
A
- stress response
- immunosuppressive drug therapy
- immunodeficency syndromes
- acute viral diseases
- decreased production (bone marrow)
12
Q
What immunosuppressive drug causes Lymphopenia?
A
tacrolimus
13
Q
What immunodeficency syndromes cause Lymphopenia?
A
- FIV
- CIV
- combined immunodeficency syndrome
14
Q
What acute viral diseases cause Lymphopenia?
A
- FeLV (acute stage)
- parvovirus
15
Q
Nucleus (Lymphocyte)
A
- round, oval
- non segmented
- mononuclear
- dark purple
16
Q
Cytoplasm (Lymphocyte)
A
- light blue
- has a high N:C ratio
17
Q
What is the size of a Small Lymphocyte?
A
7-9 microns
18
Q
Cytoplasm (Small Lymphocyte)
A
- little to no cytoplasm
- may see faint cytoplasm
19
Q
What is the size of a Large Lymphocyte?
A
9-11 microns
20
Q
Cytoplasm (Large Lymphocyte)
A
more abundant
21
Q
What is a Reactive Lymphocyte?
A
- currently being stimulated
- AKA: immunocytes, stimulated lymphocytes, activated lymphocytes
22
Q
What is the size of a Reactive Lymphocyte?
A
15-20 microns
23
Q
Nucleus (Reactive Lymphocyte)
A
- large
- dense chromatin
- chromocenters
24
Q
Cytolplasm (Reactive Lymphocyte)
A
- abundant
- intense blue
25
Where are Atyplical Lymphocytes seen?
- infections
| - neoplasia
26
Nucleus (Atypical Lymphocytes)
indented or clefted
27
Cytoplasm (Atypical Lymphocytes)
- irregular borders
| - dark blue cytoplasmic granules (due to asynchronous development of nucleus and cytoplasm)
28
What is Lymphocytopoiesis?
production of lymphocytes
29
Maturation process of a T Cell
```
PPSC
Lymphoid Stem Cell
Pre T-Cell
T-Lymphoblast
T-Prolymphocyte
T-Lymphocyte (T-Cell)
```
30
Maturation process of a B-Cell
```
PPSC
Lymphoid Stem Cell
Pre B-Cell
B-Lymphoblast
B-Prolymphocyte
B-Lymphocyte (B-Cell)
```
31
Where does the T-Cell mature?
thymus
32
Where is the T-Cell stored?
spleen (white pulp)
| lymph nodes
33
What is the T-Cell's role in immunity?
- cell mediated immunity (in tissue)
- use cytokines
- enter circulation and travel to site in tissue where antigen entered
34
What % of T-Cells are in circulation?
70%
35
Where does the B-Cell mature?
- :"Bursa Equivalent"
- GALT: gut associated lymphoid tissue
- bone marrow
36
Where is the B-Cell stored?
- spleen
- lymph nodes
- tonsils
- other lymphoid tissue
37
What is the B-Cell's role in immunity?
- humoral immunity (plasma)
- use antibodies
- rarely seen in circulation
38
What % of B-Cells are in circulation?
30%
39
Where do Natural Killer Cells mature?
bone marrow
40
Where are Natural Killer Cells stored?
- spleen
- lymph nodes
- tonsils
- lymphoid tissue
41
What is the Natural Killer Cell's role in immunity?
- non specific immunity
- 2nd line of defense
- effective against "traitor" cells
- must come in direct contact with cell
- require no activation
42
What are Memory Cells?
- B or T Cells
| - clones of the original lymphocyte
43
Where are Memory Cells stored?
survive in lymphoid tisse waiting for 2nd exposure to antigen that stimulated their formation
44
What are the parts of the Lymphatic System?
- lymphatic ducts and vessels
| - lymphatic tissue
45
What are the 3 compartments of the Lymphatic Tissue?
- bone marrow (where all cells originate)
- central lymphoid tissue (where lymphocytes mature)
- peripheral lymphoid tissues (where cells are stored until needed)
46
What are Peripheral Lymphoid Tissues?
- bone marrow
- GALT
- spleen
- lymph nodes
- tonsils
47
What is Plasma?
fluid portion of blood that carries nutrients, electrolytes, proteins, sugars, hormones etc
48
What is Lymph?
-comes from plasma
-primarily composed of water, electrolytes and sugars
doens't contain large proteins like plasma
49
What are the primary functions of the Lymphatic System?
- removal of excess tissue fluid
- waste material transport
- filtration of lymph
- protein transports
50
What things get filtered out of the Lymph?
- microorganisms
- cellular debris
- metabolic waste products
- any foreign matter or waste material
51
What proteins does the Lymphatic System transport?
-enzymes
-hormones
-other proteins
(carried from the tissue of origin into blood)
52
What are the Tissues and Organs of the Lymphatic System?
- lymph nodes
- spleen
- thymus
- tonsils
- GALT
53
Where is the Spleen located in the body?
- left side of abdomen
| - near stomach
54
What are the 2 types of function of the Spleen?
- Hematologic
| - Lymphatic
55
What are the Hematologic functions of the Spleen?
-blood storage
-removal of foreign material and debris
(occurs in the red pulp)
56
What are the Lymphatic functions of the Spleen?
-activation and cloning of lymphocytes
| occurs in the white pulp
57
True or False: The spleen is not essential for life
True
58
What is the #1 reason for a Splenectomy?
rupture/trauma
59
What is the #2 reason for a Splenectomy?
splenic tumors
60
Where is the Thymus located?
mediastinum
61
Where are the Tonsils located?
- larynx
- pharynx
- intestine
- prepuce
- vagina
62
The Tonsils are similar to the Lymph Nodes EXCEPT:
- are found near mucosal surfaces
- located at beginning of lymphatic drainage
- have no capsule
63
The GALT makes up ?% of the....
- 25%
| - small intestinal mucosa and submucosa (ileum)
64
What is the function of the Immune System?
protect the animal from anything that may cause disease or damage
65
How does the Immune System protect the animal?
recognizes "self" from "non self" and destroys "non self"
66
What is an Antigen?
any foreign substance (solid or liquid) that is capable of inducing a specific immune response
67
What is an Epitope?
uniquely shaped site on surface of antigen that is recognized by an antigen recptor
68
What determines the shape of the Epitope?
amino acid sequence
69
What is Pathogenicity?
ability of an anitgen to cause disease (how easy to get)
70
What is Virulence?
degree of pathogenicity that an antigen can cause (how sick you get)
71
What makes a "good" Antigen?
- virulence and pathogenicity
- size:bigger is better
- foreignness
- complexity and chemical stability
- dose (more=more pathogenic)
- root of administration
- host genetics or immune status
72
What is Non-Specific Immunity?
- "innate immunity"
- rapid or instantaneous in response
- generalized
73
What are the 2 type of Non Specific Immunity?
- first line of defense
| - second line of defense
74
What are the types of First Line of Defense Immunity?
- physical barriers
| - chemical barriers
75
What are the types of Physical Barriers?
- hair (coat)
- intact epithelium
- mucous membranes
- cilia
76
What are the types of Chemical Barriers?
- tears
- mucus
- saliva
- HCL acid
- normal flora
- sebum/sweat
77
What are the types of the Second Line of Defense Immunity?
- phagocytosis
- NK cells
- interferons
- complement
- inflammatory response
78
What cells can Phagocytize?
all WBCs except Lymphocytes
79
What are the steps of Phagocytosis?
- atraction
- attachment
- ingestion
- fusion
- digestion
80
What cells do NK cells attack?
traitor cells (cells infected with virus, or have become cancerous)
81
What is Perforin?
chemicals that NK cells release
| creates holes in cell => lysis
82
What are Interferons?
produced by host cell that have been infected by a virus
| have antiviral proteins
83
How do Interferons work>?
"interferes" with viral DNA/RNA replication and protein synthesis
responds rapidly to prevent further replication (~hrs)
84
What is Complement?
group of inactive enzymes in plasma
| activated with formation of an antigen/antibody complex
85
How does Complement lyse an antigen?
- complement binding sites on antbody become exposed
- complement binds to each site and becomes activated
- once all sites are occupid, complement fixation occurs
- complement arranges in donut formation on antigen =>hole forms => lysis of antigen
86
What are the 5 signs of Inflammation?
```
redness
pain
swelling
heat
decreased loss of function
```
87
What is Inflammation?
body's normal response to insult or injury
88
What is Infection?
proliferation in the body with microorganisms (bacteria, viruses, fungi, parasites etc. )
89
What is the purpose of Inflammation?
- limit the spread of pathogens and ultimately destroy them
- remove debris of damaged tissue
- initiate healing/repair of tissue
90
What is Step 1 of the Inflammatory Response?
Vasoconstriction
91
What happens during Vasoconstriction?
-prevents hemorrhage
-initiates coagulation (platelet plug forms)
(~5-10min)
92
What is Step 2 of the Inflammatory Response?
mast cell degranulation
93
What happens during Mast Cell Degranulation?
granules are released
94
Histamine
vasodilation and increased capillary permeability
95
Heparin
```
localized anticoagulant
promotes blood flow to area
RBCs=healing
WBCs=defense
PLTs=coagulation
```
96
Which of the 5 signs of Inflammation occurs during Step 2?
REDNESS
| localized hyperemia
97
What is Step 3 of the Inflammatory Response?
fluid from plasma pours into area
98
What happens during Step 3?
enzymes, antibodies, complement, plasma proteins (clotting factors) into damaged tissues
99
Which of the 5 signs of the Inflammtory Response occurs during Step 3?
EDEMA ---> impinges on nerve endings in tissue----> PAIN----> LOSS OF FUNCTION
100
What is Step 4 of the Inflammatory Response?
clot formation
101
What happens during Step 4?
wall off area adjacent to site of injury to prevent further spread of microbes
102
What is Step 5 of the Inflammatory Response?
neutrophils and macrophages inflitrate area
103
What happens during Step 5?
- removal of debris and pathogens (by phagocytosis)
| - pyrogens (produced during phagocytosis)influence hypothalamus and produce pyrexia
104
Which of the 5 signs of Inflammation occurs during Step 5?
PAIN
| HEAT
105
What are benefits to having Pyrexia?
- promotes interferon activity
- inhibit reproduction and replication of bacteria and viruses
- elevates metabolic rate to accelerate rate of tissue repair
106
What is Step 6 of the Inflammatory Response?
return to normality
107
What happens during the Return to Normality?
- histamine, heparin and other chemicals are diluted with influx of increased amount of fluid
- return to normal vessel diameter and fenestrations return to normal size
108
What are the 2 types of Specific Immunity?
cell mediated immunity
| humoral immunity
109
What are the properties of Specific Immunity?
- initiated as a reaction to an epitope on the antigen
- response is unique and specifically aimed against the antigen
- memory cells are produced
110
What is Cell Mediated Immunity?
- product of Tcells
- takes place in tissue
- effective against intracellular pathogens
- activated by macrophages
111
Where do T cells become sensitized?
in the tissue
112
What are the 3 types of "Sensitized" T Cells?
- cytotoxic T cells
- helper T cells
- suppressive T cells
113
What are Cytotoxic T Cells?
(Tc)
(CD8)
(killer cells)
114
What is the function of Cytotoxic T Cells?
-attach directly to antigen (as presented by macrophage) and destroy:
115
How do Cytotoxic T Cells destroy antigens?
- release perforins
- lyphotoxins
- induce apoptosis
- known as "lethal hit"
116
What are Helper T Cells?
(Th)
| CD4
117
What is the function of Helper T Cells?
secrete cytokines into surrounding tissues
118
What cytokines do Helper T Cells secrete into the tissue?
- interlukins
| - macrophage migration factor
119
Helper T Cells (interlukins)
chemicals that stimulate and increase activation of B cells and other T cells
120
What is the function of Macrophage Migration Factor?
attracts, stimulates and entrapts macrophages
121
What are Suppressor T Cells?
(Ts)
122
What are the functions of Suppressor T Cells?
- inhibit helper and killer T cells and stop B cells from becoming plasma cells
- release cytokines that signal all cells involved to shut down the immune response
- negative feedback mechanism
123
What is Humoral Immunity?
- product of B cells
- GALT or Bone Marrow
- takes place in plasma against extracellular pathogens
124
What activates B Cells?
formation of antigen/antibody complex
125
What are the 3 steps of when an Antibody attaches to an Antigen?
- neutralization
- agglutination and preciptiation
- complement system is activated
126
Neutralization
all active sites of antigen are bound by antibodies
127
Agglutination and Precipitation
- big conglomeration of antibodies and antigens => agglutination
- particles too big for solution => precipitate out, macrophage => phagocytize
128
What are the 5 Antibodies?
```
IgG
IgA
IgM
IgE
IgD
```
129
What is IgG?
present in greatest quantity
| makes up 75-80% of antibodies
130
When is IgG produced?
during first exposure to antigen
131
What is the production time of IgG?
slow
132
What other antibodies does IgG include?
newborn antibodies
133
What is IgA?
present in bodily fluids and secretions: mucus, saliva, tears, colostrum
prevents any disease that enters through mucosal surfaces
134
When is IgM produced?
during 2nd exposure to antigen
135
What is the production time of IgM?
fast
136
What does IgM assist with?
activation of complement
137
What is IgE?
associated with allergic responses
138
Where is IgE present?
on membrane of mast cells
139
What does IgE help to attract?
eosinophils
140
What is IgD?
function not well known
141
What is Passive Immunity?
borrowed
instant
short lived/temporary
no memory cells
142
What is Aquired Immunity?
owned
takes 2-3 weeks to develop
long lived
have memory cells
143
What is Natural Passive Immunity?
colostrum
| transplancental
144
What is Artificial Passive Immunity?
injection with immune serum from another animal (tetanus, antitoxic, antivenom, rabies, botulism)
145
What is Natural Aquired Immunity?
disease (infected -> recovered)
146
What is Artificial Aquired Immunity?
vaccination (modified live, killed, live, recombinant)
