L04. Ch 12 - Other Technologies and Automation PDF

9/23/2024 Chapter 12 Other Technologies and Automation Preamble  PowerPoints are a general overview and are provided to help students take notes over the video lecture ONLY.  PowerPoints DO NOT cover the detai...

9/23/2024 Chapter 12 Other Technologies and Automation Preamble  PowerPoints are a general overview and are provided to help students take notes over the video lecture ONLY.  PowerPoints DO NOT cover the details needed for the Unit exam  Each student is responsible for READING the TEXTBOOK for details to answer the UNIT OBJECTIVES  Unit Objectives are your study guide (not this PowerPoint)  Test questions cover the details of UNIT OBJECTIVES found only in your Textbook! 1  9/23/2024 Introduction  In response to the pressures of current good manufacturing practices (cGMP), gel test and solid-phase assays have emerged to provide accurate, reproducible blood bank testing.  Increased safety of plasticware and decreased biohazardous waste  Automated equipment and barcoding  Level of quality assurance required by current regulatory standards 4 Gel Technology  Gel particles were found to be the ideal material for trapping RBC agglutinates during standardized sedimentation or centrifugation.  Antiglobulin testing could be performed without multiple saline washes to remove unbound immunoglobulin.  Antiglobulin control cells were not needed to confirm the presence of antiglobulin reagent in negative tests. 2  9/23/2024 Gel Technology (cont’d)  Gel testing provides a more stable endpoint and more reproducible results.  It also reduces the variability associated with the physical resuspension of RBC buttons after centrifugation and the subsequent interpretation of hemagglutination reactions. Gel Technology Applications  Gel technology is currently approved by the FDA in the U.S. for ABO forward and reverse grouping, Rh typing, DAT, antibody screen, antibody identification, and compatibility testing. ABO/Rh Gel Card Screening Cell Gel Card 3  9/23/2024 Gel Technology Applications  The ABO forward grouping card contains gels that contain anti-A, anti-B, and anti-A,B.  Microtubes with buffered gel are used for ABO reverse grouping.  The Rh typing card uses microtubes filled with gel containing anti-D. 8 Gel Technology Applications  The Rh phenotype card contains gels that contain anti-D, anti-C, anti-E, anti-c, anti-e, and a control.  Microtubes filled with gel containing anti-IgG are used for compatibility testing, antibody detection, and identification. 4  9/23/2024 Gel Technology Principle  Thegel test, which is performed in a specially designed microtube, is based on the controlled centrifugation of RBCs through a dextran- acrylamide gel that contains predispensed reagents. Gel Technology Principle (cont’d)  Large agglutinates are trapped at the top of the gel and are not allowed to travel through the gel during the centrifugation.  Agglutinated RBCs remain trapped in the gel, whereas unagglutinated RBCs travel unimpeded through the length of the microtube, forming a pellet at the bottom following centrifugation. 5  9/23/2024 Gel Technology Principle (cont’d)  Agglutination reactions in the gel test graded from 1+ to 4+ (including mixed-field), just like the reactions in the test tube hemagglutination technique  False positive mixed-field reaction interpretation  Reaction grading considerations 12 Gel Reaction Chart 6  9/23/2024 Advantages of Gel Technology  Standardization of procedures  No wash step  No need for antiglobulin control cells  Decreased sample volume requirements  Enhanced sensitivity and specificity  Improved productivity Disadvantages of Gel Technology  The major disadvantages of the gel technology are the sample restrictions and the need for special equipment.  Hemolyzed, grossly icteric, or grossly lipemic blood samples  Effects of Rouleaux  Special incubators, centrifuges, and pipettes are needed 7  9/23/2024 Gel Technology Automation  Automated equipment for serological testing using the gel test is being performed successfully for ABO and Rh testing, antibody screen, compatibility testing and antibody identification in both the U.S. and Europe.  ORTHO ProVue™ Analyzer Solid-Phase Technology  Solid-phase technologies relevant to serologic testing in blood centers and transfusion services include  Solid-phase red cell adherence (SPRCA)  Solid-phase Protein A  Solid-phase enzyme-linked immunosorbent assay (ELISA) 8  9/23/2024 17 Solid-Phase Red Cell Adherence (SPRCA)  First-generation tests: the target antigen (RBCs, platelets, or platelet proteins, etc.) is added by the user to the microplate wells before testing begins.  Second-generation tests: the target antigen (RBC, platelet glycoproteins or CMV) is bound to the microplate test wells by the manufacturer during the manufacturing process. Solid-Phase Red Cell Adherence (SPRCA) (cont’d)  First- and second-generation SPRCA assays are currently approved by the FDA for antibody screening, antibody identification, Weak D testing, IgG autologous control, and compatibility testing.  Positive tests show adherence of indicator RBCs to part or all of the well bottom, depending on the reaction’s strength. 9  9/23/2024 19 Solid-phase vs. traditional tube testing Comparison of Gel and SPRCA Technologies  Procedural steps of the two technologies  Review Table 12-1  Featuresof the two technologies for routine blood bank testing  Review Table 12-2  Comparison of equipment  Comparison of test reactions and procedures 10  9/23/2024 Quality Control (QC)  Gel Testing  QC must be done on the following:  Special dispensers to prepare the RBC suspensions  Special pipettes add reagents  Each lot # of cards and diluent  SPRCA  QC must be done as follows:  Positive and Negative control with each batch  LISS has built in color change to verify addition Postamble  READ the TEXTBOOK for the details to answer the UNIT OBJECTIVES.  USE THE UNIT OBJECTIVES AS A STUDY GUIDE  Alltest questions come from detailed material found in the TEXTBOOK (Not this PowerPoint) and relate back to the Unit Objectives 11