Immunology - Lymphocytes Flashcards
What 5 ligands activate the CD4+ Th cell?
MHC II TCR CD4 B7 CD28
What is needed to induce class switching in a B Cell by a Th cell?
Th2 cytokines (IL-4, Il-5 and IL-6) CD40L and CD40
Identify and describe the process:
The coating of a bacterium with antibodies summons an important immune cell
Opsonisation, in which an antibody promotes the phagovytosis of an antigen by a phagocyte
Identify and describe the process:
The coating of a bacterium with antibodies prevents it from approaching the cells
Neutralisation, in which an antibody attaches to an antigen and prevents adherence to cells
Which cells are responsible for innate immunity?
Neutrophils, macrophages, dendritic cells, natural killer cells, and the complement system
_____ (Adaptive/Innate) immunity is encoded into the germ line and reacts to a set of static parameters that humans have adapted to combat over evolutionary time.
Innate
_____ (Adaptive/Innate) immunity has target molecules that are encoded in the germline as opposed to reacting to novel challenges.
Innate
What is the benefit of germline encoding of target antigen recognition by the innate immune system?
It allows innate immunity to be both fast and nonspecific
How does the adaptive immune response differ during first and second exposures to an antigen?
Adaptive immunity is slow to develop on first exposure but fast on any subsequent exposures
What are the components of the adaptive immune system?
T cells, B cells, and circulating antibody
Th1 and Th2 cells are specialized descendants of which type of cell?
CD4+ helper T cells
What type of T cells activate macrophages and CD8+ T cells by producing interleukin-2 and γ-interferon?
Th1 cells
What type of T cells activate B cells to make antibody by producing interleukin-4 and interleukin-5?
Th2 cells
What is the effect of interleukin-12 on T cells?
It induces the differentiation of naive helper T cells into Th1cells, resulting in increased cell-mediated immunity
What is the role of interleukin-4 in T-cell maturation?
Interleukin-4 induces the differentiation of native helper T cells to Th2 cells resulting in increased antibody-mediated immunity
Th1 cells have what functions?
The activation of macrophages and CD8+ T cells by producing interleukin-2 and γ-interferon
Th2 cells have what functions?
The activation of B cells to make antibodies by producing interleukin-4 and interleukin-5
Where in the body are T cell precursors found?
In the bone marrow
T cell precursor cells give rise to what cell type?
CD4+/CD8+ T cells
CD4+/CD8+ T cells are found where?
In the cortex of the thymus
In the cortex of the thymus
CD4+ T cells give rise to what cell line?
Helper T cells
CD8+ T cells give rise to what cell line?
Cytotoxic T cells
Interleukin-10 inhibits _____ (Th1/Th2) cells.
Th1 cells
What is the name of the set of genes that encode the major histocompatibility complex?
Human leukocyte antigen genes
On which cells is major histocompatibility complex I expressed?
Almost all nucleated cells
What are the three major histocompatibility complex I class genetic loci?
Human leukocyte antigen-A, human leukocyte antigen-B, and human leukocyte antigen-C
Which cells express major histocompatibility complex II?
Antigen-presenting cells
What are the three major histocompatibility complex II class genetic loci?
Human leukocyte antigen-DR, human leukocyte antigen-DP, and Human leukocyte antigen-DQ
For cells expressing major histocompatibility complex I, where is antigen loaded into the peptide-binding groove? Where does this occur for cells expressing major histocompatibility complex II?
Antigen is loaded into the rough endoplasmic reticulum of mostly intracellular peptides for cells expressing major histocompatibility complex I; for cells expressing major histocompatibility complex II, antigen is loaded in acidified endosomes
Which major histocompatibility complex mediates viral immunity?
Major histocompatibility complex I mediates viral immunity (via interaction with CD8+ T cells)
Which protein is paired with major histocompatibility complex I?
β2 microglobulin
On cells that express major histocompatibility complex II, where is antigen loaded into the peptide-binding groove?
Antigen is loaded in acidified endosomes
Which human leukocyte antigen subtype is associated with psoriasis, ankylosing spondylitis, inflammatory bowel disease, and Reiter;s syndrome?
B27
Which four autoimmune-related conditions are associated with human leukocyte antigen subtype B27?
Psoriasis, Ankylosing spondylitis, Inflammatory bowel disease, and Reiter;s syndrome (remember: PAIR)
Which human leukocyte antigen subtype is associated with Graves; disease?
B8
Which human leukocyte antigen subtype is associated with multiple sclerosis, hay fever, systemic lupus erythematosus, and Goodpasture;s syndrome?
DR2
Which two human leukocyte antigen subtypes are associated with type 1 diabetes mellitus?
DR3 & DR4
Which human leukocyte antigen subtype is associated with rheumatoid arthritis?
DR4
Which human leukocyte antigen subtype is associated with pernicious anemia and Hashimoto;s thyroiditis?
DR5
Which human leukocyte antigen subtype is associated with steroid-responsive nephrotic syndrome?
DR7
Which human leukocyte antigen subtype is associated with hemochromatosis?
A3
What is the primary function of B cells?
To make antibodies
Which types of organ graft rejections are mediated by B cells? By T cells?
B cells mediate hyperacute organ graft rejection; T cells mediate acute and chronic organ graft rejection
Do immunoglobulin G antibodies bind to bacteria, viruses, or both?
Both; immunoglobulin G opsonizes bacteria and inactivates viruses by binding them
Which immunoglobulin mediates allergic reactions (type I hypersensitivity)?
Immunoglobulin E
Which hypersensitivity reactions are mediated by immunoglobulin G?
Type II and type III hypersensitivity reactions