Term
|
Definition
| heavy chain portion of antibodies differentiate them |
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Term
|
Definition
| secretory phase of B cells |
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|
Term
| 4 antigenic structures recognized by antibodies: |
|
Definition
| peptides, polysaccharides, lipids and nucleic acids. |
|
|
Term
| what are the 6 activation stages of B cell maturation? |
|
Definition
| 1) contact and recognition of bug. 2) activation signals through BCR and via T help. 3) clonal expansion and differentiation. 4) antibody secretion. 5) isotype switching. 6) affinity maturation |
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|
Term
| what are the two possible isotypes of a naive B cell? |
|
Definition
|
|
Term
| what are 3 anatomical sites where B cells respond to bugs? |
|
Definition
| secondary lymphoid organs, mucosal surfaces, peritoneal cavity. |
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|
Term
| where do you find marginal zone B cells? |
|
Definition
| spleen white pulp marginal zones |
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|
Term
| where do you find B2 or conventional B cell? |
|
Definition
| lymph node germinal centers |
|
|
Term
| where do you find B-1 B cells? |
|
Definition
| mucosal tissues or peritoneal cavity |
|
|
Term
| what is the primary response of B cells? secondary response? |
|
Definition
| first exposure to bug. next time around, also called recall response. |
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|
Term
| 1) which isotype is usually present in primary responses? 2) what antibodies are present in secondary responses? |
|
Definition
| 1) Usually IgM>IgG. 2) Relative increase in IgG (but can change to IgA or IgE) |
|
|
Term
| what are NFkB, NFAT, AP1, myc ? |
|
Definition
| transcription factors that play a role in cytokine production and proliferation. |
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|
Term
|
Definition
| antibody molecule (B cell receptor) |
|
|
Term
| what is the purpose of the complement molecule? |
|
Definition
| improve signaling and lead to B cell activation |
|
|
Term
| what are two types of complement molecules? |
|
Definition
|
|
Term
| what is the significance of the secretion of low levels of IgM? |
|
Definition
| early phase of humoral immune response |
|
|
Term
| what is the T cell zone of the lymph node called? |
|
Definition
|
|
Term
| what is the B cell zone of the lymph node called? |
|
Definition
|
|
Term
| can T cells recognize the microbe directly? |
|
Definition
| NO! it recognizes linear epitopes, or itzy bitzy pieces of the microbe, NOT the whole thing. |
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|
Term
|
Definition
|
|
Term
|
Definition
| complementarity determining region |
|
|
Term
| can the B cell present antigen to T cells? |
|
Definition
| yes, it engulfs a bug then presents a MHC class II that grabs a CD4+ T helper cell. |
|
|
Term
| what is the function of the CD40/CD40L engagement between an antigen presenting B cell and a T helper cell? |
|
Definition
| allows T cell to secrete cytokines and activates the B cell to proliferate and differentiate. |
|
|
Term
| why so much control in B cell activation? |
|
Definition
| to keep the immune system from being hyperactive, on a hair trigger with every antigen it finds. It works best with the "belt and suspenders" approach. |
|
|
Term
| what is the main function of IgM? |
|
Definition
|
|
Term
| what is the main function of IgG? |
|
Definition
| opsonization, viral neutralization |
|
|
Term
| what is the main function of IgE? |
|
Definition
| mast cell degranulation, helminthes |
|
|
Term
| what is the main function of IgA? |
|
Definition
| mucosal immunity (transport through epithelial cells. |
|
|
Term
| is isotype switching reversible? |
|
Definition
|
|
Term
| how does isotype switching work? |
|
Definition
| in response to T cell signals, recombination of genes takes place and produces different isotypes. Relies on rearranged gene segments |
|
|
Term
| what happens when there is no signal from T cells during isotype switching? |
|
Definition
|
|
Term
| what is affinity maturation? |
|
Definition
| way of improving strength of binding between antibody and antigen. |
|
|
Term
| what allows for a change in affinity in antibody binding strength? |
|
Definition
| a hypermutation in the CDRs (complementarity determining regions). |
|
|
Term
| where does affinity maturation occur? |
|
Definition
| germinal centers of lymph nodes |
|
|
Term
| what is the difference between T-independent and T-dependent antigens? |
|
Definition
| T-dependent antigens are usually small monomeric (known as haptens). Whereas T-independent antigens are polymeric (LPS, glycolipds, nucleic acids). |
|
|
Term
| how does negative feedback work in the regulation of humoral immune responses? |
|
Definition
| B cells can receive direct signals from receptors that engage antigen and from cytokines from T-cells and other cells. |
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