final review for exam 1

• The cellular response includes phagocytes and is part of the immune system.
• The humoral response includes antibody production and is part of the immune system.
• CD8 is the marker on suppressor T cells.
• The cellular response includes neutrophils, macrophages, dendritic cells.
• Dendritic cells produce cytokines.
• The adaptive response is triggered by an inflammatory response.
• T cells originate in the BM but migrate to the thymus during embryonic life.
• B cells create antibodies to coat antigens, making them more visible to phagocytes and can bind complement which has cytolytic capabilities.
• Phagocytosis is aided by opsonization and/or coated with complement.
• After antigen has been engulfed by macrophages, the presenter cells break down the foreign substances into fragments and present them on their cell surface in combination with a self protein called leukocyte antigen (HLA).
• the ___________ is the second line of defense in innate immunity that involves body fluids or substances contained in a fluid

  humoral response
• Antigens present on the surface of leukocytes and tissues are known as HLA antigens, which constitute the MHC (major histocompatibility complex).
• IgD is a cell-membrane Ig found on the surface of B lymphocytes in association with IgM and is made of 2 kappa or lambda light chains and 2 delta heavy chains.
• IgG is seen in hepatitis, IM, rubella, RA, SLE, Hodgkin's Lymphoma.
• Valence of avidity is multivalent.
• IgM has 5 subunits and accounts for 10% of Ig; it is mostly intravascular as it cannot cross into tissue due to size.
• IgM is seen in bacterial endocarditis, IM, malaria, leprosy, scleroderma.
• IgD stimulates the release of IgM

  IgD is a B cell receptor
• Valence of affinity is monovalent or divalent.
• IgA is constituted of 2 kappa or lambda light chains and 2 heavy chains and accounts for 15-20% of Ig.
• Pepsin enzyme will split antibodies into two parts: F(ab) which is the top half of the molecule, and Fc which is the bottom half.
• Complement activation can also be initiated by contact with foreign surface and the bonding of C3b to hydroxyl groups on cell surface, this is the alternative pathway.
• Antibodies involved with blood group antigens usually react in a pH between 6.5-7.5 and temperatures of 4-37 degrees C.
• Complement activation ends up with water rushing into target cell and bursting it
• the classic pathway is a cascade reaction initiated by bonding of C1 complex to Ab bound to antigen on surface of bacterial cell.
• affinity refers to the strength of a single antibody-antigen interaction; each IgG antigen binding site is said to have high affinity
• IgD is not common in plasma (<1%); very susceptible to proteolysis
• IgA is seen in TB, actinomycosis, RA, and some liver disease
• antigens are usually large organic molecules, proteins, or polysaccharides
• antigenic determinants or epitopes are structures recognized as foreign
• The ABO system is the most important system in transfusion medicine because

  • almost all, healthy, normal people older than 3 months of age have naturally occurring antibodies to the ABO antigens they lack
• ABO antibodies are mostly IgM with some IgG
• ABO antibodies agglutinate without enhancement (cytokines, etc)
• ABO antibodies readily activate the complement cascade
• The ABO locus is on the long arm of chromosome 9
• Gene: H

  Glycosyltransferase: L-fucosyltransferase

  Immunodominant sugar: L-fucose
• Gene: A

  Glycoslytransferase: N-actylgalactosaminyl-transferase

  Immunodominant sugar: N-acetylgalactosamine
• Gene: B

  Glycosyltransferase: D-galactosylatransferase

  Immunodominant sugar: D-galactose
• Type O has lots of H antigen and A and B have less since its converted to A and B antigens
• Reactions seen with Bombays

  • have naturally occurring anti-H
  • will type as group O, crossmatch will fail (will react with H substance on Group O cells)
  • can only give Bombay to Bombay
  • to be certain they lack the H antigen (and are really a Bombay), can mix their red cells with a product of the plant Ulex europaeus (anti-H lectin)
  • Bombay will be negative