Chapter 22: Lymphatic System

Microphages

-nonspecific defense -neutrophils -eosinophils -enter peripheral tissues to fight infection

Macrophages

-nonspecific defense -phagocytic cells -derived from monocytes

Phagocytic APCs

1) Free and fixed macrophages -connective tissues 2) Kupffer Cells -liver 3) Microglia -CNS

Non-Phagocytic APCs

1) Langerhans Cells -skin 2) Dendritic Cells -lymph nodes and spleen 3) B Lymphoctyes Cells

7 Functions of Antigen-Antibody Complexes

1) Neutralization 2) Precipitation and Agglutination 3) Activation of complement 4) Attraction of Phagocytes 5) Opsonization increasing phagocyte efficiency 6) Stimulation of inflammation 7) Prevention of bacterial and viral adhesion

Functions of a Cytokine

1) Stimulate T Cell division 2) Attract and stimulate macrophages 3) Attract and stimulate activity of cytotoxic T cells 4) Promote activation of B cells

Cytotoxic T Cells immediately destroy target cells by..

1) release perforin- destroys antigenic plasma membrane 2) secrete lymphotoxin- destroys target cell 3) activate genes in target cell- cell will die

Each of the following is a physical barrier to infection, except epithelium. secretions. body hair. basement membranes. complement.

complement

The cells directly responsible for cellular immunity are the ________ cells. helper T suppressor T plasma cytotoxic T B

cytotoxic T cells

Light and Heavy Chains

determine specificity of antibody molecule

Adaptive Immunity

develops after birth

Which defense cells secretes lymphokines that regulate immunity? B lymphocytes memory T cells helper T cells CD8 cells

helper T cells

Four Properties of Immunity 4) Tolerance

immune system does not harm normal antigens could cause autoimmune disorder

The term ________ refers to antibodies found in body fluids.

immunoglobulins

CD Markers

in T Cell Membranes mechanism of antigen recognition

Helper T Cell Sensitization

in order for a B Cell to sensitize an antigen, it needs helper T Cell to be activated by the same antigen

Stress can affect the immune response in all of the following ways, except by inhibiting interleukin secretion. depressing the inflammatory response. increasing the level of glucocorticoids. inhibiting glucocorticoid release. reducing the number of phagocytes.

inhibiting glucocorticoid release

Passive Immunity Artificially Induced

injection of antibodies

During a primary humoral response to antigens all of the following occur, except B cells may undergo several rounds of mitosis before producing plasma cells and memory cells. B cells may differentiate into plasma cells immediately. antibody levels do not peak until 1 to 2 weeks after the initial exposure. neutrophils invade the surrounding areas, releasing chemotactic substances. the first immunoglobulins to appear in circulation are of the IgM type.

neutrophils invade the surrounding areas, releasing chemotactic substances

Primary and Secondary Responses to Antigen Exposure

occur in body cell-mediated and antibody-mediated immunity

Innate Immunity

present at birth

First exposure..

produces initial primary response

Stem cells that can form all types of lymphocytes are concentrated in the thymus. red marrow. circulation. yellow marrow. spleen.

red bone marrow

Cytotoxic T cells can attack target cells with which of these chemical weapons? secrete mutant proteins secrete free radicals secrete strong acid secrete organic solvent secrete a cytokine that triggers apoptosis

secrete a cytokine that triggers apoptosis

Memory B Cells

similar to memory T cells, remain in reserve to respond to next infection

Interleukins do all of the following, except elevate body temperature. increase T-cell sensitivity to antigens exposed on macrophage membranes. stimulate inflammation. stimulate collagen synthesis. stimulate B-cell activity, plasma cell formation, and antibody production.

stimulate collagen synthesis

Plasma Cells

synthesize and secrete antibodies into interstitial fluids

Primary Response

takes time to develop antigens activate B cells plasma cells differentiate antibody titer level slowly rises

Next Exposure...

triggers secondary response more extensive and prolonged

Antibody Structue

two parallel paris of polypeptide chains -one pair of heavy chains -one pair of light chains *each chain contains constant segments and variable segments

MHC + Antigen =

Antigen Recognition

Two Main Divisions of an Immune Response 2) Antibody-Mediated Immunity

B Cells attack by circulating antibodies

Lymphatic vessels are located in almost all portions of the body, except the groin. periphery. CNS. throat. renal arteries.

CNS

Two Main Divisions of an Immune Response 1) Cell-Mediated Immunity

T Cells direct physical and chemical attack

Secondary Response

activates memory B cells secretes antibodies in massive qualities

Passive Immunity Naturally Acquired

antibodies acquired from the mother

Passive Immunity

antibodies are transferred from another source

Active Immunity

antibodies develop after exposure to antigen

B Cells

antibody-mediated immunity produces specific antibodies

B Cell Sensitization

antigen is taken into B cell-processed-reappear on surface, bound to class II MHC protein

Four Properties of Immunity 2) Versatility

body produces many types of lymphocytes each fights a different type of antigen

Four Properties of Immunity 1) Specificity

each T or B cell responds only to a specific antigen

Active Immunity Naturally Acquired

environmental exposure to pathogens

T cells and B cells can be activated only by exposure to a specific antigen at a specific site in a plasma membrane. cells infected with viruses, bacteria, or cancer cells. pathogens. disease-causing agents. interleukins, interferons, and colony-stimulating factors.

exposure to a specific antigen at a specific site in a plasma membrane

Two Classes of MHC Proteins 2) Class II

found in membrane of antigen-presenting cells (APCs-responsible for activating T cells against foreign cells and proteins) lysosomal action produces antigenic fragments Antigenic fragments are displayed by Class II MHC Proteins on plasma membrane

Two Classes of MHC Proteins 1) Class I

found in membranes of all nucleated cells pick up small peptides in cell and carry them to the surface T Cells ignore normal peptides abnormal peptides are displayed by Class I MHC proteins on plasma membrane T Cells destroy

CD8 Markers

found on cytotoxic T cells and suppressor T cells respond to antigens on Class 1 MHC protiens

CD4 Markers

found on helper T cells respond to antigens found on Class 2 MHC Proteins

Which of these is not a property of the immune response? It must be acquired. It may be cell-mediated. It is triggered by an antigen. It may be antibody-mediated.

it must be acquired

Four Properties of Immunity 3) Memory

lymphocytes stay in circulation immunity against new exposures

Immunity that results from exposure to an antigen in the environment is called ________ immunity. passive naturally acquired active natural passive innate auto

naturally acquired active

Immunity that results from antibodies that pass through the placenta from mother to fetus is called ________ immunity. active innate auto naturally acquired passive passive

naturally acquired passive

Active Immunity Artificially Induced

through vaccines

Binding Sites

tips of two variable segments form antigen binding sites of antibody molecule