Specific Immunity Flashcards
Function of T lymphocytes?
cellular immune response and regulation of B lymphocytes and macrophages
What percentage of all leukocytes do eosiinophils comprise?
1-6%
When B cells encounter antigen, they differentiate into ____ and produce _____.
plasma cells; antibodies
What percentage of WBCs do neutrophils comprise?
40-75%
Cytotoxic T cells have which type of co-receptor?
CD8
What is the first step in the complement cascade that combines the two pathways?
C3 activation
What cytokine stimulates the growth of helper T and NK cells?
IL-2
Monocytes comprise what percent of all leukocytes?
2-10%
T-cell glycoproteins: What is the CD3 complex?
a cluster of polypeptides associated with a T-cell receptor. It is important in signal transduction
Which Ig isotype is found in secretions?
IgA
Which major cytokines re produced by macrophages? (3)
IL-1, IL-6, and TNF-alpha
Name two markers present on T helper cells.
CD3, CD4
What influence doe gamma interferon have on MHCI and II?
upregulates MHCI and II in all cells.
What do TNF-alpha and TNF-beta do? (3)
increase IL-2 output and B-cell proliferation, attract neutrophils
The amino terminal is part of which fragment of the antibody?
fab fragment
Where do B-lymphocytes mature?
bone marrow (B= bone marrow)
What is secreted in the granules of a basophil? (2)
heparin (anticoagulant), histamine (vasodilator), other vasoactive amines
Which cytokines promote the growth and differentiation of B cells? (3)
IL-4, IL-5, TNF-alpha
What recognizes endogenously synthesized (viral or self) proteins that are presented by MHC I?
TCR on cytotoxic T cell
In the tissues, monocytes differentiate into which cells?
macrophages
CD4 cell secretes which growth factor to activate the CD8 cells?
IL-2
Which Ig isotype guards the mucous membranes from attachment of bacteria and viruses?
IgA
Name two markers present on cytotoxic T cells.
CD3, CD8
The classic pathway is initiated by which Ig isotypes?
IgM or IgG
Which co-stimulatory signal is needed for a helper T cell to be activated by MHC II on an APC?
B7 (protein on APC) and CD28 (receptor on helper T cell)
What is the function of an eosinophil?
defend against heminthic and protozoan infections
Primary granules in a neutrophil are called?
lysosomes
What is the term called when the antibody prevents bacterial adherence?
neutralization
CD4 on helper T cells bind to what?
MHC II on antigen-presenting cells
In an environment with a lot of IL-12, naive helper T cells will mature to which helper T cell?
Th1 cell
Which markers identify T cells? (2)
TCR and CD3
What do primary granules in a neutrophil contain? (4)
hydrolytic enzymes, lysozyme, myeloperoxidase and lactoferrin
Which cytokine stimulates the synthesis of IgA?
IL-5
T-helper cells secrete which cytokines? (4)
IL-2, IL-4, IL-5, gamma interferon
What does CD stand for?
cluster of diffrentiation
What are the causes of eosinophilia? (6)
neoplastic, asthma, allergic processes, collage vascular diseases, parasites (NAACP)
What are the effects of the cytokines produced by macrophages? (4)
causes the liver to make more complement; fever; mobilizes neutrophils from bone marrow; helps T-cells migrate to lymph nodes and mature
Which interleukin is an endogenous pyrogen?
IL-1
Which is the physically largest antibody isotype?
IgM
Which cytokine stimulates the synthesis of IgE and IgG?
IL-4
What marker disappears when B cells become anergic?
IgM is internalized in anergic cells
B lymphocytes are part of the ______ immune response.
humoral
Why do Th1 cells produce IL-2 and gamma-interferon?
to activate macrophages (increase killing efficiency of intracellular bacteria) and CD8 cells
What does a lack of C1 esterase cause and why?
angioedema-which is basically overactive complement.
Eosinophils are highly phagocytic for _________.
antigen-antibody complexes
Which Ig isotype induces the release of mediators from maast cells and basophils when exposed to an antigen?
IgE
Why does an antibody activate complement? (2)
to enhance opsonization and lysis
What does C3a do?
think A for inflAme-anything that ends in ‘a’ acts to increase the inflammatory response. C3a leads to anaphylaxis, along with C5a.
Name four types of cells that T cells differentiate into.
cytotoxic, helper, suppressor, delayed hypersensitivity
Which helper T cell is involved in cell-mediated immunity?
Th1 cell
Which cells secrete IL-2?
helper T cells
Which growth factor induces the maturation from naive helper T cell to Th2 cell?
IL-4
Which part of the light and heavy chain recognizes the antigen?
variable part
What is the main antibody in a second response to an antigen?
IgG
What markers are present on B-lymphocytes? (2)
CD19 and CD20
T cells mature in the _______.
thymus
Which cytokine stimulates eosinophil production?
IL-5
What cytokines are responsible for the acute phase response? (3)
IL-1, IL-6, TNF-alpha
IgE stimulates which type of hypersensitivity reaction?
type 1
IL-4 and IL-5 are released from Th2 to activate what type of cell?
b cell
The constant part of the heavy chain of IgM and IgG does what?
fixes complement
The hypervarible region is a component of which fragment of the antibody?
fab fragment
Which enzyme in neutrophils creates the free radicals which kill bacteria?
NADPH oxidase
The helper T cell is activated to produce which two cytokines in cell-mediated immunity?
IL-2 and gamma-interferon
T/F: The nucleus of basophil is trilobed.
false, bilobed
Monoblasts are progenitors of _______.
monocytes
Which helper T cell is involved in antibody-mediated immunity?
Th2 cell
C3b does what?
think B for binding-anything that ends in b acts to opsonize bacteria
Which type of cell is more sensitive to anergic stimulus?
T cells
CD4 are on which type of T cells?
helper T cells
Is a neutrophil response consistent with acute or chronic inflammation?
acute
Which Ig isotype crosses the placenta?
IgG
IL-1 by itself causes what effects? (5)
fever, stimulates the growth and differentiation of T and B cells neutrophils, fibroblasts and epithelial cells
Cytoplasm of monocyte looks like _________.
frosted glass
What is the shape of the nucleus of an eosinophil?
bilobed
What do alpha and beta interferon do?
degrade viral mRNA, thereby inhibiting viral protein synthesis.
What is the shape of monocyte nucleus?
kidney shaped
Which cytokines act to attract neutrophils? (2)
IL-8 (major) and TNF-alpha (minor)
When is IgM produced?
primary response to an antigen
What is the purpose of interferons?
interferons interfere in viral infection of cells and replication. They also activate NK cells to kill infected cells.
What is the difference between TNF-alpha and TNF-beta?
TNF-alpha is secreted by macrophages and TNF-beta is secreted by T lymphocytes. Their functions are similar.
What is the purpose of opsonizaation?
the antibody promotes phagocytosis
Th 1 secretes which growth factor to activate CD8 cells?
IL-2
Why does complement act preferentially against gram bacteria?
complement initiators like to bind to carbohydrates, so gram-bacteria are noticed more than others.
How does the acute phase reaction cause a fever? (3)
IL-1 acts on the hypothalamus to increase body temp, fat is mobilized to increase energy, and muscle mass is used to create heat
CD4 cell secretes which three cytokines to activate B cells?
IL-2, IL-4, IL-5
What is the shape of the nucleus of lymphocyte?
small, round, densely staining
What are the function of macrophages? (20
phagocytize bacteria, cell debris and senescent red cells; scavenge damaged cells and tissues.
Which substances activate the aternate pathway?
everything else (other than IgG and IgM) -endotoxins, microbial surfaces, IgA, etc.
What does a lack of C3 cause?
severe and recurrent pyrogenic infections of the sinuses and UR tract, because C3 is the first common step in both pathways
Gamma interferon is secreted by which helper T cell to activate macrophages?
Th1 cell
IL-2 from the helper T cell activates which cell to kill virus-infected cells?
cytotoxic T cell
Which isotype fixes complement but does not cross the placenta?
IgM
Which Ig isotype fixes complement, crosses the placenta, opsonizes bacteria, and neutralizes bacterial toxins and viruses?
IgG
Class ___ MHC molecules present antigen to CD ____ positive cytotoxic T cells.
class I; CD8
Class ____ MHC molecules present antigen to CD ____ positive T helper cells.
class II; CD4
Name two markers for NK cells.
receptors for MHC I, CD 16
What kind of bacteria does complement act against?
gram negative
In what pathologic condition are hypersegmented neutrophils seen?
B12/folate deficiency
Which Ig isotype has the lowest concentration in the serum?
IgE
CD8 on cytotoxic T cells bind to what?
MHC I on virus infeted cells
Why do Th2 cells produce IL-4 and IL-5?
to help B cells make antibody
T-cell glycoproteins: When a cell first gets infected with a virus which three cells respond?
APC, B cell (through IgM BCR), and CD8 (through TCR and MHC I on infected cell)
Exotoxins are ____ molecules presented by ____ on antigen-presenting cells to ____ cells which stimulate ____
Exotoxins are peptide molecules presented by MHC II on antigen-presenting cells to CD4+ T cells which stimulate antibody and memory B cell generation.
