week 1 (B and T cells immunity)

B cells, T cells, Immunity

what is the definition of serology?

the scientific study or diagnostic examination of blood and serum especially with regard to the response of the immune system to pathogens and introduced substances

what three big things does serology set out to do?

autoimmune/ allergy detection, analysis of infectious disease, organ transplant candidacy

what is the definition of immunology?

study of how the immune system attempts to recognize and destroy anything considered dangerous to our bodies

what are the exogenous sources of “danger” to our immune system?

fungi, viruses, bacteria, parasites

what are endogenous sources of “danger” to our immune system?

damaged/infected cells, cancerous cells

what are the three lines of defense of the immune system?

barrier immunity, innate immunity, adaptive immunity

what makes up barrier immunity?

skin, hair, mucous membranes, temperature, tears, HCl stomach acid

what is innate immunity?

non-specific immunity carried out by granulocytic and phagocytic cells with the same response regardless of the type of pathogen

what is adaptive immunity?

specific response immunity carried out by B cells and T cells

how does innate immunity work? What do macrophages recognize for gram neg bacteria? Gram pos? Viruses?

macrophages recognize pathogen associated molecular patterns (PAMPs) on pathogens, lipopolysaccharides on gram negative bacteria, lipoteichoic acid on gram positive bacteria, double stranded RNA or viral glycoproteins on viruses

what are cytokines?

proteins released by cells that affect behavior of other cells that bear receptors on them

what are chemokines?

cytokines that tell immune cells to move to the site of infection

what are interleukins?

major cytokines

what does IL-I do?

cause fever, reduced apatite, lethargy

What does IL-8 do?

recruits and activates neutrophils

what do IL-2 and IL-12 do?

activate NK cells

What does the release of IL-6 from the liver do?

releases acute phase proteins like CRP

what cytokine is called the “OG Antibody?”

CRP

what is CRP?

an acute phase reactant that binds to phosphocholine on the surface of bacterial cells acting as an opsonin marking the bacteria for destruction

What are the physiological affects of cytokines? (9)

fever, inflammation, induces kinin systems, vasodilation, vascular permeability, decrease BP, mast cell degranulation, induction of clotting system, recruitment of WBC’s

what type of organisms have innate immunity?

all multicellular species

what does the inflammatory response do to lymph flow?

increases lymph flow

what does the lymphatic system do?

maintains healthy fluid levels in the body

there are two major lymph ducts in the chest, the _______ duct and the _______ duct. After filtering through thy lymph nodes, these ducts merge into the ________.

right lymphatic duct, thoracic duct, subclavian veins

what do the subclavian veins do?

remove cellular debris

what do lymph nodes do?

filter lymph to identify pathogens via B and T cells

cells that mature in the thymus are called _____, this includes ______ and _______ cells

Thymocytes, CD4+, CD8+

what are antigen presenting cells?

phagocytes that have phagocytized bacteria and become activated and then present these pathogens to T cells

what cells are specialized to be antigen presenting cells?

dendritic cells

how do dendritic cells opperate?

immature dendritic cells constantly sample their environment via tendril like appendages. Once a pathogen has been detected the dendritic cell becomes activated and brings the pathogen to T cells

what is VDJ recombination?

gene recombination via RAG enzymes that results in lots of genetically diverse B cell receptors and T cell receptors

what enzymes are responsible for VDJ recombination?

RAG enzymes

what are the 4 steps to create a CD4+ or CD8+ T cells?

double negative immature T cells in the thymus, positive selection, negative selection, cell signals cause T cells to drop either CD4 or CD8

what are double negative T cells?

immature T cells hang out in the thymus and have no CD receptors

what is T-cell positive selection?

thymic endothelial cells present MHC molecules to T cells and only those that can bind to them are selected

what is a double positive T cell?

T cells that are both CD4+ and CD8+ positive

what is negative T cell selection?

double positive T cells interact with APC’s to test if they will react to self and only those that don’t are selected for

what are self tolerant T cells

T cells that have passed the negative selection test

How many V segments are there? D segments? J segments?

51, 27, 6

how many unique VDJ combinations are there?

10^11

MCH molecules are located on what type of cell?

any non-nucleated cell

what type of cells do CD8+ T cells become?

cytotoxic/ Killer

CD8+ cytotoxic T cells can only bind to which type of MHC molecule?

MHC 1

what type of T cell do CD4+ cells become?

helper T cells

CD4+ helper T cells can only bind to what type of MHC molecule?

MHC 2

B cells that have become activated in a lymph node by a pathogen and travel back to the bone marrow become what type of cell?

plasma cell

B-cell receptors are identical to what other structure?

the antibody they make

B and T cells that have become activated can both become what type of cell

memory cells

what are the 2 types of light chains?

kappa and lambda

what are the 5 functions of antibodies?

toxin neutralization, activating complement, agglutination, bind to viruses, act as opsonin

seeing only IgM antibodies indicates what type of infection?

early infection

seeing IgG antibodies only indicates what type of infection?

past or chronic infections

seeing both IgG and IgM antibodies indicates what kind of infections?

recent or reoccurring infections