B&L Unit 1 Flashcards
Ensures that each B cell expresses a unique antibody. Only one parental copy of the allele is expressed and other is silenced. Diploid organisms inherit one copy from each parent.
Allelic Exclusion
Mature B cell starts by making IgM & IgD membrane-bound antibodies. Later it may switch to IgG, IgE, or IgA. The V domain stays the same and the same but C region of heavy chain changes. Changes are irreversible.
Heavy Chain Class Switching
Immunity resulting from utilizing products of someone else’s immune system. System is designed by mother nature. Ex. newborn who is breast feeding.
Natural, Passive Immunity
Immunity results from real-life exposure to pathogen. Longest lasting type of immunity.
Natural, Active Immunity
Immunity resulting from the use of immune serum or purified antibodies to protect a patient at risk from a particular disease.
Artificial, Passive Immunity
Immunity resulting from intentional immunization with vaccines, toxoids, or other antigenic preparations.
Artificial, Active Immunity
dsRNA. Molecules associated with groups of pathogens, that are recognized by cells of the innate immune system. They are recognized by Toll-like receptors (TLRs) and other pattern recognition receptors (PRRs) in both plants and animals.
Pathogen-Associated Molecular Pattern
Primary cell type in germinal center of lymph node follicle. Clonal deletions of these developing cells occur in the bone marrow. After antigen stimulation, somatic hypermutation in these cells causes even greater receptor diversity. Produces antibodies.
B Cell
10 polypeptide chains. Major isotype in milk. Most important antibody in GI tract.
IgA
Mediates warm autoimmune hemolytic anemia. Activates complement. Crosses placenta to provide protection to fetus. Opsonizes targets for removal by phagocytes. Neutralizes viruses. Half life is 3 weeks.
IgG
Mediates cold autoimmune hemolytic anemia.
IgM
Involved in allergic reaction and parasite reaction. Mast cells have receptors for this antibody’s Fc.
IgE
Part of antibody molecules that contacts the antigenic determinant.
Hypervariable Region
Allele of the antibody chains found in an individual.
Allotype
Cells that have antigen-specific receptors. Pokeweed mitogen stimulates cellular division.
T & B Lymphocytes
Lyses bacteria. Opsonizes bacteria. Attracts phagocytic cells. Can be activated in absence of antibody.
Complement
Immunity of this cell type involves: antigen, angry macrophages, inducer T cells (Th1), and secretion of lymphokines. May contain CD4 or CD8 proteins.
T Cells
Chemotactic for PMNs.
C5a, Leukotriene B4, IL8, bacterial product
Part of membrane attack complex that polymerizes in the membrane to form a transmembrane channel.
C9
Least abundant type of white blood cell in peripheral blood. 0.5% - 1% normal differential.
Basophil
Does not change when B cell switches from making IgM to IgG antibodies.
Light Chain
40% to 60% normal differential.
Neutrophils
20% to 40% normal differential.
Lymphocytes
2% to 8% normal differential.
Monocytes
1% to 4% normal differential.
Eosinophils
Young neutrophil. 0% to 3% normal differential.
Bands
Order of white blood cell differential percentages.
band < basophil < eosinophil < monocyte < lymphatic < neutrophil
Central lymphoid organs in humans.
Bone Marrow & Thymus
In order, gene segments of immunoglobulin heavy chain mRNA.
V, D, J, Constant
Acts as bridge between innate and adaptive immune system. Phagocyte. Antigen-presenting cell.
Dendritic Cell
Volume % of erythrocytes in whole blood.
Hematocrit
Loss of this protein leads to inc. reticulocyte index due to inc. spherocytosis.
Spectrin Defect (protein in cytoskeleton)
Dec. serum iron, dec. ferritin, dec. % saturation, inc. total iron binding capacity (TIBC).
Iron Deficiency
Average hemoglobin per RBC.
Mean Corpuscular Hemoglobin (MCH)
Description of dec. mean corpuscular hemoglobin (MCH).
Hypochromic
Description of inc. mean corpuscular hemoglobin (MCH).
Hyperchromic
Cells in bone marrow from which platelets are derived.
Megakaryocytes
Hemoglobin type that contains 4 beta hemoglobin genes.
Hemoglobin H
Inc. serum lactate dehydrogenase (LDH), inc. serum indirect bilirubin, inc. urine hemoglobin, inc. reticulocyte count.
Hemolysis
= hematocrit / RBC count
MCV
= 100 - age
Bone Marrow Cellularity
Dec. Hgb, dec. MCV, dec. MCH.
Microcytic, Hypochromic Anemia
Description of dec. MCV
Microcytic
Description of inc. MCV
Macrocytic
Manifestations include: hand-foot syndrome, aplastic crisis, anemia, splenic sequestration
Sickle Cell Anemia
Generally only causes disease in setting of diabetes. Leads to fungal infections.
Neutrophil Myeloperoxidase
Diagnostic cycle of 21 +/- 4 days
Cyclic Neutropenia
Medicine commonly used in severe congenital neutropenia.
Granulocyte Colony Stimulating Factor (G-CSF)
Region on antibody that binds to antigens. It is composed of one constant and one variable domain of each of the heavy and the light chain.
Fragment Antigen Binding Region (Fab)
When enzyme pepsin cleaves Fab at hinge region, which two fragments are created?
F(ab)2 and Fragment Crystallizable Region (Fc)
Process by which B cells and T cells are deactivated after they have expressed receptors for self antigens and before they develop into fully immunocompetent lymphocytes.
Clonal Deletion
Cellular mechanism by which the immune system adapts to the new foreign elements that confront it (eg. microbes), as seen during class switching.
Hypermutation
Present on every nucleated cell in human body. Presents epitopes of proteins made by cell to cytotoxic T cells. “Look what I’ve made!”
Major Histocompatability Complex 1 (MHC1)
Helper T Cells bind to this on antigen presenting cells (macrophages, B cells, dendritic cells). “Look what I’ve eaten!” Presents epitope of antigen that has been digested.
Major Histocompatability Complex 2 (MHC2)
Protein on helper T cells that binds MCH 2.
CD4
Protein on Cytotoxic T Cells that binds to MCH 1. Kills infected cells.
CD8
