Flashcards in Lecture 6: Intro To Immunology Deck (39):
What is the most important cytokine that caues the multipotent hematopoietic stem cell to differentiate into the common lymphoid progenitor?
[the common lymphoid progenitor cell line then branches to NK cells, T cells, and B cells]
In the initial generation of lymphocytes, what 2 cell types are generated in the bone marrow?
B cells and Pro-T cells
DiGeorge syndrome results from a contiguous deletion of _________ through _________.
Symptoms inclue thymic _________ or ________, hyperparathyroidism, congenital heart malformation, and/or characteristic _________.
Patients experience recurrent infections soon after birth.
22q11.21 through 22q11.23
Hypoplasia; aplasia; facies
True or false: complete DiGeorge syndrome is fatal without treatment
Absence of the thymus would result in no T cell maturation. Mature T cells are also used in the complete differentiation of B cells, so you are essentially losing the adaptive branch of your immune system.
How would you classify the lymphocytes constantly recirculating between the blood and peripheral lymphoid organs?
Mature naive (because they are developmentally mature, but have not yet encountered an antigen)
What happens to migrating T cells and B cells if they become activated by APCs?
They stop migration in order to become fully activated to perform their effector function
Of all the secondary lymphoid organs, rank the spleen, LNs, intestines (GALT), and lungs (BALT) in order of most lymphocytes to least lymphocytes
What is the primary APC responsible for travelling to secondary lymphoid tissues and presenting Ag to mature naive T cells?
[the antigen is presented within MHC class I or II]
Humoral immunity is the branch of adaptive immunity mediated by antibodies produced by _____ cells and ______ cells.
Humoral immunity is the principle adaptive defense against ____________ pathogens
Antibodies complexed with phagocytes participate in what 2 effector functions?
Neutralization of microbes and toxins
Opsonization and phagocytosis of microbes
What is the effector function of antibodies complexed with NK cells?
Antibody-dependent cellular cytotoxicity (ADCC)
What is the effector function of antibody-mediated complement activation (classical pathway)
Phagocytosis of microbes opsonized with complement fragments (C3b)
Lysis of microbes
During pregnancy, the mother provides a physical barrier for the fetus against microorganisms.
The fetus receives ____ from the maternal circulation.
Additional protection will be gained through ____ secreted in breast milk.
Cell-mediated immunity is a branch of adaptive immunity mediated by _____________ and ___________. Cell mediated immunity is the principle adaptive defense against ____________ pathogens.
T lymphocytes; macrophages
What are the "two paths" of cell-mediated immunity?
CD4+ effector T cells interact with phagocytes that have ingested microbes in vesicles --> cytokine secretion --> macrophage activation and killing of ingested microbes
CD8+ CTL interacts with infected cell with microbes or antigens in the cytoplasm --> direct killing of infected cell
What are the 3 sub-types of CD4+ T helper cells?
What is the signature cytokine of Th1 cells and what is the immune reaction?
Leads to macrophage activation and IgG production
What are the signature cytokines of Th2 cells and what are the immune reactions?
Lead to mast cell and eosinophil activation, IgE production, and M2 macrophage activation (alternative)
What are the signature cytokines of Th17 cells and what is the immune reaction?
Leads to neutrophilic and monocytic inflammation
Th1 cells defend the host against what type of pathogen?
[role in autoimmune disease; tissue damage associated with chronic infections]
Th2 cells protect the host against what type of microbes?
[also role in allergic diseases]
Th17 cells provide protection against what types of pathogens?
[also play a role in autoimmune inflammatory diseases]
APCs (like dendritic cells or macrophages) with ingested microbes utilize ______ to activate naive CD4+ T cells to differentiate them into Th1 effector T cells.
The Th1 effector cell can then activate macrophages to kill the microbes via _______ (cytokine)
CD8+ cytotoxic T lymphocytes are antigen-specific and have MHC restricted cytotoxicity.
They are involved in the killing of ___________ pathogens using stored lytic _______ that contain cytotoxins.
Cytotoxins are delivered directly onto the surfaces of infected target cells.
What does it mean to say that cooperation exists between CD4 and CD8 T cell subsets?
A macrophage that has phagocytosed microbes in vesicles and cytosol can be activated by IFN-y secreted by CD4+ T cells. The microbes will then be killed in the phagolysosome, and the infected cell can then be killed by CD8+ CTLs
Adaptive immune responses provide ongoing protection by production of memory lymphocytes.
During the primary immune response, when the Ag is first encountered, activation of naive cells takes place to form effector functions, and there is generation of ___________ cells.
The secondary immune response, when the Ag is encountered again, the memory cells are activated and there is a stronger, ________ immune response
____________ = antigenic stimulus that elicits specific adaptive immune responses that can be recalled during subsequent infections
__________ immunization is the introduction of antibody or antiserum into a naive recipient
________ immunization is the introduction of an antigen that provokes an adaptive immune response
___________ is the intentional delivery of an antigenic stimulus
What are the 2 identifiers on B cells?
What is the identifier present on all T cells?
What are the identifiers on helper T cells?
CD3+ CD4+ helper T cells can be further identified based on their cytokine secretion profile. What cytokines does Th1 produce?
CD3+ CD4+ helper T cells can be further identified based on their cytokine secretion profile. What cytokines does Th2 produce?
CD3+ CD4+ helper T cells can be further identified based on their cytokine secretion profile. What cytokines does Th17 produce?
What are the identifiers present on Treg cells?
What cytokines are secreted by Treg cells?