micro chapter 17 part 3

cellular immunity: the __ of the T cell recognizes MHC and allows __ to recognize epitope-both have to bind at the same time for it to be successful

CD, TCR

T-cell characteristics: if the cell expresses __ with TCR, it will commit to be a helper T cell

CD4

T-cell characteristics: TH (__) bind antigen presented on MHC class 2 of the __-__ cell (APCs=dendritic cells, macrophages, B cells)

CD4, antigen-presenting

helper T cells: effector functions of __ cells: recognize antigens presented on MHC class 2 of APCs (once activated-release __)

CD4, cytokines

cytotoxic T cells: effector functions of __ cells: Tc induces apoptosis by releasing digestive enzymes (perforins and granzymes), and also released cytokines that alert neighboring cells

CD8

cytotoxic T cells: effector functions of __ cells: recognize antigen on MHC class 1 of infected host cells

CD8

T-cell characteristics: two main CD subsets in T cells: __ (Tc) and __ (TH); two main MHC classes: __ __ and __ __

CD8, CD4, class 1, class 2

T-cell characteristics: is a cell expresses __ with TCR, it will commit to be a cytotoxic T cell; any __ can present intracellular pathogens on its surface-MHC class 1

CD8, CD8

T-cell characteristics: Tc (__) bind antigen presented on MHC class 1 of any __ host cell

CD8, nucleated

cellular immunity: __ is a receptor for HIV-infects helper T cells

HIV

which maternal antibody classes protect a breastfed newborn?

IgA

Why is negative selection important?

It eliminates lymphocytes that would otherwise recognize "self" molecules

mechanism: step 1: clonal selection: __ __ cells will find a pathogen, detect it, take it in, process it, present on MHCs

sentinel dendritic

cytotoxic T cells: cytotoxic T cell with CD8 binds to __ __ __, TCR recognizes epitope that is bound to it and cytotoxic T cells releases toxins, specifically __ and __ to induce apoptosis

MHC class 1, perforin, granzymes

mechanism: step 1: clonal selection: pool of T cells available, __ __ is able to recognize antigens presented on MHCs-this one will be selected

specific clone

__ __ can only be activated by intracellular antigens when presented on MHC

T cells

cellular immunity: helper T cells (TH) and cytotoxic T cells (Tc) have __ and __ of __ to recognize antigens only presented on MHC of others cells (MHC + antigen)

TCR, clusters, differentiation

T-cell characteristics: __ cells recognize antigens presented on MHC class 2 molecules

TH

T-cell characteristics: __ cells recognize antigens presented on MHC class 1 molecules

Tc

what is meant by clonal selection?

The antigen, by binding to the lymphocyte receptor, "selects" which lymphocyte may begin multiplying.

what is the function of lymph nodes?

there are secondary lymphoid organs; where B cells and T cells gather and encounter antigens that flowed through the lymphatic vessels from the tissues

how does a naive lymphocyte differ from an activated one?

a naive lymphocyte has never "seen" the epitope to which it is programmed for; activated lymphocytes have encountered the epitope and have received any required signals to proliferate and elicit the corresponding adaptive immune response

would a plasma cell produce antibody molecules of the same specificity or different specificities?

a single specificity; each B cell is programmed to recognize a specific epitope, and all plasma cells that descend from that B cell make antibodies that bind to the particular epitope

__ immune system: acquired through infection or vaccination, specific recognition and memory

adaptive

how does the ability to bind antigen increase as B cells multiply?

affinity maturation; mutations occur in the multiplying B cells, and the progeny that has the strongest affinity for the antigen is more apt to multiply

during maturation, undergo __ __: __ and __ selection before released from thymus; migrate to lymphatic system and concentrate in the __ __

thymic selection, positive, negative, lymph nodes

immature lymphocytes that are destined to be T cells

thymocytes

what kind of diseases would be expected to occur as a result of lack of negative selection of T or B lymphocytes?

autoimmune diseases

thymocytes leave bone marrow and migrate to the __- __ TCR here and associate TCR with the __-__ (CD); all TCRs expressed on one T cell recognize the same antigen-__ __

thymus, mature, co-receptor, same specificity

__-__ immune response: activated by intracellular antigen and presented on MHC

cell-mediated

__-__ immune response: defend against intracellular pathogens and cancer by binding to and initiating apoptosis in infected cells or cancer cells

cell-mediated

mechanism: step 2: clonal expansion: activated cells leave lymph nodes and circulate in the body-__ and other __ will attract cytotoxic T cells to the site of infection and they look for infected cells that has an antigen presented on their MHC __ __-destroy it

chemokines, chemoattractants, class 1

T-cell characteristics: __ __ is the MHC class expressed by all nucleated cells in the body (exceptions are erythrocytes and thrombocytes, non-nucleated)-have the ability to bind __ pathogens onto their MHC and express it on their surface

class 1, intracellular

T-cell characteristics: MHC __ __ can only be expressed by APCS (dendritic cells (phagocytes), macrophages (phagocytes), and B cells); whenever using this class, presents to get confirmation from __ __ __, must bind to antigen to be able to present on surface

class 2, helper T cells

mechanism: step 2: __ __: activated T cells proliferate and differentiate into effector T cells and memory T cells

clonal expansion

cytotoxic T cells: released, undergo __ __, leave lymph, to to infected site-look for infected cells; know they are infected because something able to bind __ __ __ has bound and presented it (one method of communication)

clonal expansion, MHC class 1

helper T cells: effector function of CD4 cells: secrete cytokines that: 1. activate B cells and induce B cell __ __; gives __ to B cell to activate humoral response

clonal expansion, confirmation

undergo __ __ to give effector T cells (active helper T cell or active cytotoxic T cell) that will mount immune response against pathogen; __ __ __ will be long-lived and get activated upon subsequent exposures

clonal expansion, memory T cell

mechanism: step 1: __ __: dendritic cells migrate through the lymph and present epitope on MHC to mature naive T cells; activation of T cell

clonal selection

T cells wait in lymph nodes to be activated-will be activated if matching by release of __ from dendritic cell (__ __)

cytokines, clonal selection

mechanism: step 2: clonal expansion: __ __ __ are toxic to infected cells

cytotoxic T cells

which cell type recognizes peptides presented on MHC class 1 molecules?

cytotoxic T cells recognize antigen presented on an MHC class 1 molecule; whereas helper T cells can recognize antigen presented on an MHC class 2 molecules

mechanism: step 1: clonal selection: cytokines released can activate __ __ __ and __ __ __

cytotoxic T cells, helper T cells

__ __ brings antigen to T cell in lymph nodes; these are in __ (skin, mucosal layer) scouting to present antigen on MHC-bring to closest lymph node

dendritic cell, tissue

which type of leukocyte functions as a main bridge between the innate and adaptive immune system?

dendritic cells

helper T cells and cytotoxic T cells both produce __ T cells and __ T cells (effector cytotoxic T cells and effector memory T cells; cytotoxic helper T cells and memory helper T cells)

effector, memory

mechanism: step 2: clonal expansion: activated TH (CD4) cells, by MHC class 2-bound antigen, differentiate into __ helper T cells and __ TH cells

effector, memory

mechanism: step 2: clonal expansion: activated Tc (CD8) cells, by MHC class 1-bound antigen, differentiate into __ cytotoxic T cells and __ Tc cells

effector, memory

How would the adaptive immune response be affected if memory cells could not be produced?

every response would be equivalent to a primary response (taking a week or so to develop, and first antibodies made would be IgM)

mechanism: step 2: clonal expansion: __ __ __: core of immune response through cytokines that are released (mainly __)-activate other cytotoxic T cells, B cells, phagocytes, amplifying immune response

helper T cells, interleukins

__ immune response: activated by extracellular antigen

humoral

__ immune response: defend against extracellular pathogens by binding to antigens, thereby neutralizing pathogens or making them better targets for phagocytes and complement proteins

humoral

__ __: internal defense mechanism against pathogens

immune system

__ immune system: immediate, non-specific immunity, no learning process or memory

innate

cellular immunity: pathogen went __ cell and is being presented on the __: could be a pathogen taken in and __; __ __-infect cell and replicates in cell, proteins that are made can be presented on MHC-constant monitoring

inside, surface, phagocytized, viral components

cellular immunity: carried out by T cells which combat __ pathogens (viral protein within a cell, phagocytized molecules)

intracellular

helper T cells: effector function of CD4 cells: secrete cytokines that: 2. activate __ (and other phagocytes) to increase power and use to form giant cells: increased __, __, number of __; (more effective!)

macrophages, size, metabolism, lysosomes

__ in the thymus decides whether it will be a helper T cell or cytotoxic T cell; thymocytes are not specialized when they travel to the thymus, specialize in thymus during __

maturation, maturation

cytotoxic T cells: __ __ cells ensure faster secondary response

memory Tc

Could a TC cell induce apoptosis in a "self" cell that lost the ability to produce MHC class I molecules?

no, Tc cells rely on antigen presentation on MHC class 1 molecules to recognize that a cell is infected; natural killer cells could

mechanism: step 1: clonal selection: dendritic cells can present on class 2, but are __ and can present on class 1; can activate both __ T cells and __ T cells-considered a bridge between innate and adaptive immune system

nucleated, helper, cytotoxic

helper T cells: effector function of CD4 cells: secrete cytokines that: increase macrophage __: increases size, metabolism, number of lysosomes, produces __ __ and other toxic compounds

power, nitric oxide

helper T cells: effector function of CD4 cells: secrete cytokines that: 3. direct and support Tc cells __ and __ (help T cells make more faster)

proliferation, differentiation