Immunology Overview

differentiation of stem cells into all other blood cell types

Innate

Basic: mvmt of WBC (leukocytes) to site of infection (recruitment).

Reflect intensity of CURRENT infection

Includes: increased vascular permeability, erythema, heat, edema, pain

lineage taken by stem cells destined to be leukocytes that participate in innate immunity

gives rise to myeloid cells (leukocytes)

1. Monocyte (immature)/Macrophage (mature)

2. Neutrophil (PMN)

• mononuclear
• make up 5% of leukocytes

• most prominent in WBC
• part of granulocyte family (others are eosinophils and basophils)
• multiple nuclei

serve as chemoattractants and activators in innate and adaptive immunity

produced by phagocytes, fibroblasts, endothelial cells of blood vessels

surface mem structures that promote binding btw cells as they collaborate during particular function

• 1. selectins (initial)
• 2. integrins (secondary)

leukocytes in bloodstream can be diverted to site of infection outside blood stream; dep on gradients of chemoattractants

• 1. primary adhesion (selectins)
• 2. secondary adhesion (integrins)
• 3. diapedesis

Pathogen Associated Molecular Patterns: molecular groupings or patterns found on the surface of the pathogen that allow binding during phagocytosis

Pattern Recognition Receptors: on surface of phagocyte; for PAMP recognition/binding

Toll-Like Receptors: lg family of PRRs involved in recognizing molecular patterns expressed by bacterial and fungal polysaccharides

• (respiratory burst)
• O2---->Superoxide---->hydrogen peroxide---->hypochlorite ions

• acidified env
• antimicrobial peptides (defensins)
• enzymes (lysozymes)
• competitors (lactoferrin)

particles coated with particular substances that increase efficiency of phagocytosis (overcomes capsules)

substance capable of being specifically recognized by receptors on B and T lymphocytes

lineage that gives rise to leukocytes involved in adaptive immunity

specific region of antigen that is unique; 2 categories:

• 1. linear: one cont string of molecular constituents
• 2. conformational: discont regions brought together by 3D folding of antigen

low molec wt substances that can be recognized by antibodies of appropriate specificity but cannot induce antibody response unless coupled to an immunogenic carrier

• Most: proteins
• second: polysaccharides
• least: lipids/NA

• 1. mult diff to self
• 2. large size
• 3. complex composition
• 4. particulate and denatured form

• 1. few diff to self
• 2. small size
• 3. simple composition
• 4. soluble and native form

• 1. int dose
• 2. route: subcutaneous>intramuscular>intraperitoneal>intravenous
• 3. adjuvant: substances that mix with antigen and promote slow release and non-specific inflammation, i.e. mineral oil and alum precipitates

• 1. v high or v low dose
• 2. intravenous route (see extrinsic increased)
• 3. adjuvants that do NOT promote slow release and non specific inflammation

key lymphocytes in humoral immunity; make specific, antigen-reactive glycoproteins called antibodies; progenitors of plasma cells; can act as accessory cells

key lymphocytes in cell-mediated immunity

req for processing and presentation of antigen to T lymphocytes; includes macrophages, dendritic cells, and B cells

where lymphocytes are born and matured;

bone marrow, thymus

where lymphocytes eventually live

spleen, lymph nodes, Peyer's patches, tonsils, blood

each lymphocyte produces on its surface mem one set of receptor molecules w/ identical specificity for a particular antigenic determ (epitope)

activation of a single lymphocyte that produces a clone of lymphocytes w/ specificity for single epitope

immune response against complex antigens w/ mult epitopes that activate numerous clones of lymphocytes (each w/ specificity for ind epitope)

when an antibody recog two antigens that are not identical but share one or more closely related or identical epitopes