Unit 5 Part 2 PDF - Immunohematology

SPECIALIZED AREAS OF MEDICAL TECHNOLOGY IMMUNOHEMATOLOGY IMMUNOHEMATOLOGY ★ Refers to the serologic, genetic, biochemical, and molecular study of antigens associated with membrane structures on the cellular constituents of blood, as well as the immunolo...

SPECIALIZED AREAS OF MEDICAL TECHNOLOGY IMMUNOHEMATOLOGY IMMUNOHEMATOLOGY ★ Refers to the serologic, genetic, biochemical, and molecular study of antigens associated with membrane structures on the cellular constituents of blood, as well as the immunologic H: Complete Hemolysis properties and reactions of blood PH: Partial Hemolysis components and constituents ABO TYPING RA 7719 ★ Determines the ABO type of an individual ★ Components: ○ Forward Typing (Direct or Red cell Typing) TERMS ○ Reverse Typing (Indirect or ★ Blood bank / center Serum/ Plasma Typing) ○ a laboratory or institution with the capability to recruit and ABO TYPING: Forward screen blood donors, collect, process, store, transport and Detects unknown antigen on the red cell issue blood for transfusion and using known commercial AntiSera provide information and/or Anti-A: Blue education on blood transfusion Anti-B: Yellow transmissible diseases ★ Hospital-based blood bank AntiSera ○ a blood bank which is located ★ a serum that contains immunoglobulins within the premises of a hospital from blood of human or animals and which can perform inoculated with an antigenic material or compatibility testing of blood; from those that recovered from a ★ Blood collection unit disease when they naturally developed ○ an institution or facility duly certain antibodies against particular authorized by the Department of antigens. Health to recruit and screen donors and collect blood; ★ Voluntary blood donor ○ one who donates blood on one's own volition or initiative and without monetary compensation;  ABO TYPING: Reverse Detects unknown antibodies (naturally occurring) using known commercial antigen 2-5% Red Cell suspension Rh TYPING ★ Detects RhD using known Anti-D Reagent ★ No reverse typing (Rh antibodies are Determine the blood type: FORWARD typing unexpected antibodies) ANTI-A ANTI-B Interpretation 4+ 0 0 3+ 4+ 4+ 0 0 ANTIHUMAN GLOBULIN TEST Determine the blood type: REVERSE typing ★ AHG ★ Detects IgG- or Complement coated RBC A-cell B-cell Interpretation ★ has specificity for the FC portion of the heavy chain of the human IgG molecule 4+ 0 or complement components. 0 3+ 4+ 4+ 0 0 GEL TECHNOLOGY ★ agglutination test based on controlled centrifugation of RBCs through a ANTIHUMAN GLOBULIN TEST dextran-acrylamide gel that contains pre dispensed reagents. DIRECT ANTIHUMAN GLOBULIN ★ DAT ★ Detects in vivo sensitization of RBC with IgG/ complement components ★ Clinical Conditions ○ Diagnosis of HDFN ○ Investigation of HTR ○ Diagnosis of AIHA EDTA Blood - Sample of Choice  PROCEDURE OF DAT ★ Components ○ Immediate-Spin Washed RBC + AHG reagent ○ Antihuman Globulin Does not require incubation Add Check cells if negative ANTIHUMAN GLOBULIN TEST INDIRECT ANTIHUMAN GLOBULIN ★ IAT ★ Detects in vivo sensitization of RBC ★ Used in the following: ○ Antibody detection ○ Antibody Identification ○ Antibody titration INTERPRETATION ○ Red Cell phenotyping ○ Crossmatching COMPATIBLE ★ If there is no agglutination or hemolysis in all tubes PROCEDURE OF IAT INCOMPATIBLE PATIENT RED CELLS ★ If there is agglutination or hemolysis in Incubate anti-sera all tubes Wash 3x Add AHG reagent Add Check cells if negative PATIENT SERUM Incubate RGT red cells Wash 3x Add AHG reagent Add Check cells if negative REAGENTS IMMUNOLOGY & SEROLOGY POLYSPECIFIC AHG ★ contain antibody to human IgG and to IMMUNOLOGY the C3d component of human ★ defined as resistance to disease, complement specifically infectious disease. MONOSPECIFIC AHG SEROLOGY ★ Contain only one antibody specificity: ★ the study of the fluid components in the either anti-IgG or antibody to specific blood, especially antibodies components of complement, such as C3b or C3d Antigen ★ Substance that reacts to antibody CROSSMATCH TEST Antibody ★ Final Check of ABO compatibility ★ Product of exposure to foreign between donor and patient immunogen ★ May detect the presence of antibodies not detected during antibody Identification SERUM INACTIVATION SEROLOGIC CROSSMATCH ★ The process that destroys complement activity. ★ Test the px serum with the Donor RBC  ★ Complement is known to interfere with SERIAL DILUTION the reactions of certain syphilis tests and complement components ★ MULTIPLE DILUTION PROCEDURE PHYSICAL ○ Heating 56°C for 30 Minutes ○ EX. Venereal Disease Laboratory (VDRL) Test for Syphilis CHEMICAL ○ Add Choline chloride Ex. ○ EX. Rapid Plasma Reagin (RPR) Suppose you set up a series of 10 tubes. You Test for Syphilis pipet 0.8 mL of saline into tube 1 and 0.4 mL of saline into tubes 2 to 10. Next, 0.2 mL of a serum sample is added to tube 1. The tube is mixed, SERUM RE-INACTIVATION and 0.4 mL is serially transferred through tube 10. Finally, 0.1 mL of antigen is added to all the ★ When more than 4 hours has elapsed tubes. What is the final titer of tube 4? since inactivation, a specimen can be reinactivated by heating it to 56°C for 10 minutes. DILUTION ★ making weaker solutions from stronger solutions ★ indication of relative concentration. ★ Two entities: ○ SOLUTE - which is the substance being diluted ○ DILUENT - which is the medium making up the rest of the solution. Ex. Suppose 2 mL of a 1:20 dilution of serum is needed to run a specific serological test. What volumes of serum and diluent are needed to IMMUNOASSAY / SEROLOGICAL TEST make this dilution? ★ Test that uses the principle of antigen antibody reaction ★ Types: ○ Direct/ Forward: Test used to detect unknown antigen using known antibody ○ Indirect/ Reverse: Test used to detect unknown antibody using known antigen  PRECIPITATION ★ involves combining soluble antigen with soluble antibody to produce insoluble complexes that are visible. ★ Precipitin-Antibody that can cause precipitation IMMUNOTURBIDIMETRY ★ involves measurement of the turbidity or cloudiness of a solution. NEPHELOMETRY ★ measures the light that is scattered at a particular angle from the incident beam as it passes through a suspension PRECIPITATION W/ ELECTROPHORESIS IMMUNOFIXATION ELECTROPHORESIS ★ IFE ★ antiserum is applied directly to the gel’s surface rather than placed in a trough ★ used to identify and characterize serum or urine proteins PASSIVE IMMUNODIFFUSION RADIAL IMMUNODIFFUSION ★ Single-diffusion technique involving migration of antigen only. ★ reagent antibody is uniformly mixed into the support gel ★ Positive Result: Precipitin Ring Normal OUCHTERLONY DOUBLE DIFFUSION Monoclonal IgG ★ Both antigen and antibody diffuse independently through a semisolid medium in two dimensions, horizontally and vertically.  AGGLUTINATION CO-AGGLUTINATION ★ process by which particulate antigens, ★ Uses antibodies bound to a particle to such as cells, aggregate to form larger enhance the visibility of agglutination. complexes when a specific antibody is ★ Carrier: Bacterium present. ★ Ex. Staphylococcus aureus with Protein A Agglutinin ★ Antibody that can cause agglutination AGGLUTINATION-INHIBITION ★ based on competition between DIRECT AGGLUTINATION particulate and soluble antigens for limited antibody combining sites ★ Antigens are found naturally on the ★ lack of agglutination is an indicator of a surface of the particles positive reaction. ★ Ex. ★ Involves: Haptens attached to carrier ○ Blood typing particles ○ Kauffman and White Serotyping ★ Ex: HCG test, detect antibodies to certain ○ Widal Test viruses ○ Weil-Felix ○ Rubella ○ Cold Agglutinin Test ○ Influenza ○ Respiratory syncytial virus (RSV) PASSIVE AGGLUTINATION ★ antigen is artificially attached to a particulate carrier ★ e.g. cells, latex, bentonite, celloidin, charcoal ★ Detects: antibodies to viruses such as ○ Rotavirus ○ Cytomegalovirus ○ Rubella ○ Varicella-zoster ○ HBV, HIV, HCV REVERSE PASSIVE AGGLUTINATION ★ Antibodies are attached to particulate carriers ★ Active sites of antibody are facing outward ★ often used to detect microbial antigens. ★ Application: ○ Group B Streptococcus ○ Staphylococcus aureus ○ streptococcal groups A and B ○ Rotavirus ○ Cryptococcus neoformans