Antibodies PDF - BSMLS 3-Y1-6

Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. ANTIBODIES How fast they will settle down in test tube after VALENCE of an antibody centrifugation - Number of antigen bindi...

Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. ANTIBODIES How fast they will settle down in test tube after VALENCE of an antibody centrifugation - Number of antigen binding sites. Most are bivalent. Other notes: - Product of T-cell activation Abundancy (pinaka marami) - Left to right (GAMDE) - Binding site of antigen-antibody - IgG, IgA, IgM, IgD, IgE - More valence, more binding site = powerful/stronger Arrangement based on who is produced - Properties: IgM, IgD, IgG, IgA, IgE (MDGAE) Protein mainly in nature (not all, but IgM - first produced by b-cell mostly) IgG, IgA, IgE - produced by memory b cell IgM- pinaka mabigat/malaki (900k) With high molecular weight (compact, di IgG- pinaka magaan/maliit (150k) madali masira) Present in serum/plasma, saliva, CSF and BASED ON TEMPERATURE ACTIVITY other body fluids (almost all body fluids) COLD - IgM active Antibodies are also called immunoglobulin WARM IMMUNOGLOBULIN - IgG active Glycoprotein molecules which are produced by - IgG can cause blood transfusion reaction plasma cells because the body is warm (not applicable Derives their name from the findings that when to those who live in cold environments) antibody-containing serum is place in an electrical field, the antibodies, which were responsible for ACCORDING TO OCCURRENCE immunity, migrated with globular proteins. IMMUNE - Acquired when produced by b cell after FUNCTIONS: exposure to antigens/infections Neutralize toxic substances NATURAL - Any poisonous substance - Present at birth/naturally occurring Facilitate phagocytosis and kill microbes - Either bacteria, virus, fungi, parasite ACCORDING TO SPECIES WHO PRODUCE THEM Combine with antigens on cellular surfaces and ISOANTIBODIES hereby cause the destruction of these cells - When a cell is infected, antibodies bind to - Antibody produced for own/ to protect own it and start apoptosis (once the cell is HETEROPHILE infected, there is no way to save it) - Antibody produced for other spp ACCORDING TO ITS REACTION WITH ANTIGEN CLASSES OF ANTIBODIES 1. Agglutinins and Agglutinoids ACCORDING TO SEDIMENTATION - Agglutination is caused by antibodies when an antigen is bonded to a cell (ex: blood typing) 2. Precipitins - 1 soluble antigen, 1 antibody - Antigen-antibody is not bonded to any cell (free-flowing)  Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. Light chain - With two antigenically defined 3. Hemagglutinins types: kappa and lambda - Same as no. 1 4. Lysins - To lyse/burst 5. Opsonins - It will coat the antigen for easy grip and swallow (phagocytosis 6. Neutralizing antibodies - For toxic substances 7. Allergic antibodies - Start allergic reactions =constrict vessels para di makadaan and antigen - Histamine and heparin (ends allergic Antibody can be cut into two: reaction) Fab (Antigen binding fragment) 8. Antitoxins - Binds to antigen /germs - Same as no. 6 Fc - crystalization 9. Complement fixing antibodies - Produce other functions of antibody 10. Blocking of inhibitory antibodies (neutralization of toxins, agglutination) ACCORDING TO THEIR IN-VITRO BEHAVIOR HEAVY CHAIN (in-vitro: inside body) Has four regions/domains: 3 constant COMPLETE ANTIBODY - determines the antibody's class and its Synonyms: effector functions - Bivalent; Saline-acting 1 variable Response to Temperature - contributes to antigen specificity - Thermolabile Ability to cross the placenta Effector functions and class - Cannot cross the placenta 50k Daltons INCOMPLETE ANTIBODY Synonyms: LIGHT CHAIN - Univalent; Blocking; Coagglutinating Has two main types: kappa and lambda (not both) Response to Temperature: Has two regions/domains: - Thermostable 1 constant Ability to cross placenta: - Stability, structural integrity - Can cross the placenta 1 variable - Together with the variable region of the ANTIBODY STRUCTURE heavy chain, forms the antigen-binding Antibody is made up of Tetrapeptide with a site four-chain (2 heavy chain, 2 light chain) nunit molecule: Disulfide bond - bind the site Heavy chain - With five principal antigenic Where antigens bind types with their corresponding Ig. (gamma, 25k Daltons alpha, mu, delta, epsilon)  Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. IDIOTYPE VARIABLE REGION CONSTANT REGION (for specificity/what antigen to bind) Amino acid sequence Amino acid sequence is unique antigenic determinants found in the subject to change fixed and unchanging variable region of (heavy and light chain) an Amino terminal end Carboxyl terminal end antibody (NH2) (COOH) specific to the antigen-binding site vary from one antibody to another based on the Concerned with binding Concerned with antigen it targets. to antigen binding to host tissue defines the precise structure of the antigen-binding site and is responsible for the specificity of the immune response. HINGE REGION Flexible part of the antibody located in the heavy chains. Located between the CH1 and CH2 regions Papain acts here to produce Fab and Fc portions ISOTYPE Determines the half-life of the antibody refer to the class of antibodies, which are defined by the constant region of the heavy GAD has, ME do not chains. IgG, IgA, IgD = has hinge region Changes in the constant of Heavy chain IgM, IgE = no hinge region Types of Isotypes: ANTIBODY DIGESTION IgG (gamma heavy chain) PEPSIN IgA (alpha heavy chain) - below the hinge IgM (mu heavy chain) - Cut into 2 parts = IgE (epsilon heavy chain) 1 Fab IgD (delta heavy chain) 1 Fc prime (small) PAPAIN - Above hinge region ALLOTYPE - Cut into 3 parts (subscript) 1 Fab small differences are found in the constant 1 Fab regions of the heavy or light chains. 1 Fc (whole) important in transplantation and blood transfusions THEORIES OF ANTIBODY genetic polymorphisms within a species that EHRLICH’S SIDE CHAIN cause slight variations in antibody structure. do not affect the overall function of the antibody Certain cells has had specific surface receptors class for antigen that were present before contact with antigen occurred Once antigens was introduced, it would select the cell with proper receptors, the combination would  Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. take place and then receptors will break off and IgG4 has short hinge region enter the circulation as antibody molecules. Antigen/germ pipili ng isang cell, then yung cell ay mag pproduce ng antibody IgA CLONAL SELECTION Dimer (2) , 10-15% of Total Ig Individual lymphocytes are genetically Synthesized at a greater rate than IgG pre-programmed to produce one type of Synthesized in plasma cells found in immunoglobulin, and that specific antigen finds mucosal-associated lymphoid tissue (MALT) or selects those particular cells capable of Half-life: 6 days responding to it, causing these to proliferate Cannot start complement pathway that is why Repeated contact with the antigen would we don’t usually get inflammation if there is an continually increase a lymphocyte pool infection in mucosal surface/membrane. Antigen/germ pipili ng antibody na nasa cell (1 Functions are: antibody, 1 cell) , once nag dikit, si cell ay mag Patrol (guard) mucosal surfaces, Prevent cclone para maraming cell ma produce adherence of organism on mucosal surface/membrane Protection for infant digestive tract CLASSES OF ANTIBODY Act as the first line of defense. Neutralize toxins IgG Smallest monomer (1) Has 2 subclasses: Predominant immunoglobulin in humans IgA1 mainly found in serum, a monomer 75% to 80% of total Ig. has longest life span of 23 to 25 days** IgA2 usually found in mucus membranes or surfaces, a dimer with J chain Functions are: Provide immunity for newborn since it can cross placenta Starts complement pathway Coats antigen for enhanced phagocytosis IgM Neutralize toxins and viruses Pentamer; star-shaped in free state Participate in agglutination and precipitation Half life is 10 days (6 days). reactions. 5 to 10% of total Ig Has 10 functional binding sites but only 5 is Has 4 subclasses: usually used unless antigens are very small. IgG1 has a large hinge region Cannot cross placenta First to appear in maturing infant First to appear in infection but not for long. IgG2 has short hinge region, least effective Synthesized only as long as antigen is present in crossing the placenta because there is no memory cells for IgM. Functions are: IgG3 has the largest hinge region Starting of complement pathway (most effective of all Ig in classical complement pathway)  Antibodies Immunology & Serology | BSMLS 3-Y1-6 Yabut, Kirsten Chloe E. Agglutination (best because of its 10 binding synthesized by plasma cell found in lung and sites) skin Surface receptor on B cells for Ag Opsonization Functions are: Toxin neutralization destruction of large antigen such as parasitic worm Has two forms: triggering of acute inflammatory reaction. Pentamer found in secretions and fluids of the body such as saliva and blood Monomer found on surface of B cells IgD Monomer Has half-life of 2 days (3 days) (because of long hinge region) Heat labile Second to appear after IgM on an onset of infection Does not cross placenta Does not start complement pathway Does not bind neutrophils or macrophages Found on immunocompetent but unstimulated B cells. Function is: B (memory) cell activation, maturation, and differentiation IgE Monomer Least abundant of all immunoglobulin Most heat labile of all immunoglobulin Cannot start complement pathway Cannot agglutinate Cannot opsonize Cannot cross placenta Found on basophil and mast cells. - Mast cells are found in lining of respiratory and alimentary tracts, and the skin.