Immune Function

Immunity

pathogens

bacteria

virulence

viruses

host cell

cancer cells

“clean-up”

External defenses

skin

epidermis

keratinocytes

melanocytes

Langerhans cells

Granstein cells

dermis

sweat glands

sebaceous glands

saliva

mucosal modifications

mucous

alveolar macrophages

Resistance to inflection

white blood cells (leukocytes)

polymorphonuclear leukocytes

neutrophils

eosinophils

basophils vs. mast cells

monocytes

lymphocytes

B cells

T cells

NK cells

properties

diapedesis

ameboid motion

chemotaxis

margination

phagocytosis

enzymatic digestion

peroxisomes

reticuloendothelial system

Nonspecific immune responses: innate immunity

inflammation

defense by resident tissue macrophages

localized vasodilatation

increased capillary permeability

localized edema

walling-off of inflamed area

tissue thromboplastin

emigration of leukocytes

leukocyte proliferation

leukocytic destruction of bacteria

opsonization

pus

phagocyte-secreted chemical mediation

direct action

NO (nitric oxide)

lactoferrin

release of histamine

triggering of clotting/anticlotting mechanisms

formation of active kinins from kininogens

kallikrein

endogenous pyrogen (EP)

secretion of leukocyte endogenous mediator (LEM)

reduction of plasma iron concentration

promotion of granulopoiesis

acute-phase proteins

interleukin 1 (IL-1)

proliferation and differentiation of B and T lymphocytes

tissue repair

scar tissue in nonregenerative tissues

salicylates and glucocorticoids

interferon

promotes formation of viral-blocking enzymes

NK cells

complement

classical pathway

Ag-Ab complex activates C1

opsonization and phagocytosis [C3b]

lysis [C5b6789_n]

agglutination

viral neutralization

chemotaxis [C5a]

basophil/mast cell activation [C3a, C4a, C5a]

inflammatory effects

lectin pathway

alternative (or alternate) pathway

large polysaccharides react with factors B and D

formation of activation product that activates C3

If the complement discussions seem a little confusing, I highly recommend the
animation showing the assembly of C1 during the classical pathway,
animation showing the assembly of C3 convertase,
animation showing the cleavage of C3 and the formation of C5 convertase,
animation showing the formation of the MAC,
animation showing the benefits of C5a and C3b,
animation of the lectin pathway,
animation of the alternative pathway and formation of C3 convertase, and
animation of the formation of C5 convertase.

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Immune Function 2

Specific immune responses

general concepts

humoral immunity

plasma cells

cell-mediated immunity

activated T lymphocytes

internship and residency of lymphocytes

antigens and immune triggering

haptens

B lymphocytes and antibody-mediated immunity

antigen binding

plasma cell differentiation

immunoglobulins

structure

antigen-binding fragment (Fab)

constant (Fc) region

classes

IgG

Fc region binds with phagocytic cells

IgM

IgA

IgE

Fc regions binds with mast cells and basophils

IgD

modes of action

interfering with antigen effect

neutralization

agglutination

precipitation

augmenting nonspecific immune effects

activation of complement system through C1

enhancement of phagocytosis

opsonization

stimulation of killer (K) cells

immune-complex disease

clonal selection theory of B-cell production

plasma cells

memory cells

primary response

secondary response

natural immunity as a special case of actively acquired immunity

ABO blood groups as example

transfusion reaction

Rh factor

erythroblastosis fetalis or hemolytic disease of the newborn

antigen processing and presentation

APCs

MHC molecules

compartment for peptide loading (CPL) organelle

interleukin 1 and B-cell proliferation

T_H cells and B-cell growth factor

T lymphocytes and cell-mediated immunity

basics

viral and fungal infections

tumors and xenograft rejection

regulatory roles

lymphokine production

activated only when antigen presented in context of self ¹

T cell types

cytotoxic T cells (CD8+ or T_C cells)

viruses

perforin molecules

helper T cells (CD4+ or T_H cells) ²

B-cell growth factor

T-cell growth factor (interleukin 2 [IL-2])

chemotaxins

macrophage-migration inhibition factor

“angry” macrophages

acquired immunodeficiency syndrome (AIDS)

human immunodeficiency virus (HIV)

helper T cell subsets

helper T cell naïveté

T helper 1 (T_H1) cells

interleukin 12 (IL-12)

stimulation of eosinophil antihelminthic activity

promotion of cell-mediated response

T helper 2 (T_H2) cells

interleukin 4 (IL-4)

promotion of humoral response by B cells

suppressor T cells (T_S cells)

immunologic tolerance

mechanisms

clonal deletion

clonal anergy

antigen and B7 presentation

inhibition by T_S cells

antigen sequestration

granting of immune privilege

autoimmune diseases

human leukocyte-associated (HLA) antigens

major histocompatibility complex (MHC)

immune surveillance

benign tumors

malignant tumors

metastasis

immune neuroendocrinology and neuroendocrine immunology

interleukin 1 promotes cortisol release

neuroendocrine receptors are found on lymphocytes and macrophages

Immune diseases

immunodeficiency

congenital

acquired

AIDS

severe combined immunodeficiency (SCID)

inappropriate immune attacks

autoimmune responses

Disease	Affected organ(s)
juvenile-onset diabetes	pancreatic beta cells
rheumatoid arthritis	joints
ankylosing spondylitis	spine
multiple sclerosis	myelin in the central nervous system
thyrotoxicosis	thyroglobulin
rheumatic fever	heart valves
myasthenia gravis	acetylcholine receptors at the neuromuscular junction
ulcerative colitis	intestine
male infertility (some)	spermatozoa
systemic lupus erythematosis	most organs
amyotrophic lateral sclerosis	motor neurons in the spinal cord

immune-complex diseases

allergies

immediate hypersensitivity (type I)

IgE molecules attach to mast cells/basophils

chemicals released

histamine

slow-reactive substance of anaphylaxis (SRS-A)

eosinophil chemotactic factor

hay fever vs. asthma

anaphylactic shock

delayed hypersensitivity

T cell mediated

poison ivy