Who is Immulab?
Pioneering Immunohaematology in Australia, Immulab is dedicated to delivering diagnostic confidence and enhanced patient safety. We specialise in the production of Australian manufactured Reagent Red Blood Cells (RRBCs), monoclonal blood grouping reagents and ancillary products, supported by a team of proficient blood bankers.
Immulab focuses on the manufacture of a range of IVDs, distribution of blood bank automation, OEM, and technical services. Immulab holds numerous contracts for large-scale supply of our range of liquid red cells, antisera and supplementary products with laboratories domestically and internationally. We are also proud distributors of the Immucor range of Transfusion and Transplantation products.
What are Reagent Red Blood Cells?
Reagent Red Blood Cells (RRBC) are diagnostic reagents that are used to determine a patient’s blood group and antibody status. Reagent red blood cells are made from human red blood cells and are used for ABO/Rh testing, antibody screening and antibody identification. Other supplementary reagent red blood cell products include cord cells, A2 cells as well as RhD Negative screening cells to assist in screening antenatal samples when Anti-D is present.
What is the importance of Blood Banking?
Blood banking, also referred to as transfusion medicine, is the process of performing diagnostic tests to ensure that donated blood and blood products are safe and compatible for transfusion into a recipient patient.
Pre- 1900, transfusion medicine had limited success and was often fatal. The first successful transfusion of human blood to a patient occurred in 1818. However, it wasn’t until the 1900s that modern transfusion medicine was born. In 1900 Austrian physician Karl Landsteiner discovered the first 3 human blood groups, A, B and O, and in 1907 it was suggested by Luvig Hektoen that safety of transfusion might be improved by crossmatching blood between donors and patients to exclude incompatible mixtures. By the 1920’s, the MNSs and P systems were discovered with the Rh blood group being discovered in 1939. By the late 1930’s refrigeration technology allowed for blood to be stored or banked allowing for hospital laboratories to store donated blood thus originating the term Blood Bank.
Today, transfusion laboratories and blood banks are located in hospitals and centres where blood or blood products are needed. Not only do these labs store and dispense donated blood but they are also responsible for all the pre-transfusion testing of patient samples to ensure safe transfusion of blood and blood products. Transfusion-related errors can have serious consequence for patients, including death. For this reason, blood banking plays a vital role in patient care.
What are Anti-Human Globulin reagents?
For the blood bank, the quality of an Anti-Human Globulin (AHG) reagent is critical in detection and identification of antibodies. AHG reagents are used in antibody screening, antibody identification and cross matching. When human immunoglobin (IgG) antibodies attach to their appropriate red cell antigens, they may fail to cause agglutination of the red cells, but will remain firmly bound even when the cells are washed in saline - known as red cell sensitisation. The presence of the bound antibody may be detected by the addition of an AHG reagent. There are two methods used when detecting the presence of red cell antibodies; the Indirect Antiglobulin Test (IAT) and the Direct Antiglobulin Test (DAT). The Indirect Antiglobulin Test (IAT) detects antibody and/or complement coating red cells following incubation with serum or plasma in vitro, whilst the Direct Antiglobulin Test (DAT) detects antibody and/or complement coating red cells that has occurred in vivo.
What are Phenotyping reagents?
Phenotyping reagents are used in transfusion diagnostics to characterise antigens present on red blood cells. Characterising the red cell antigens of a patient allows for enhanced compatibility and reduces risk of developing a red cell alloantibody which has the potential to cause difficulties for ongoing transfusion support, particularly for transfusion-dependent patients. These patients should have an extended red cell phenotype (or genotype) determined before their initial transfusion.
What tests are run before a blood transfusion?
Pretransfusion testing is important to ensure suitable products are used for transfusion. It involves testing for the most clinically important blood group systems which are the ABO and Rh blood group systems. In addition to typing for ABO and Rh, it is also important to know if antibodies against other non-ABO blood groups (alloantibodies) are present. This is often referred to as an Antibody screen, whilst ABO and Rh testing is referred to as a “Forward and Reverse” or “Group” test.
Together, a “Forward and Reverse” test and “Antibody Screen” form the basis of Pretransfusion testing in blood bank often referred to as; Group and Screen, Type and Screen, Group and Hold, or a Group and Save.
What blood groups make up an extended phenotype?
In addition to the ABO, and Rh blood group system, an extended phenotype is used in incidences where there are alloantibodies and to avoid creating additional alloantibodies in more complex transfusion-dependent patients. There are currently 43 International Society of Blood Transfusion (ISBT) recognized blood group systems that contain 345 red cell antigens (June 2021). Testing for all red cell antigens is not possible so the focus for an extended phenotype is usually limited to more relevant blood group antigens and those that are considered clinically significant. System Name Antigens
MNS system M N S* s*
Duffy System Fya* Fyb*
Kidd System Jka* Jkb*
Kell System K* k*
Lewis System Lea Leb
Luthern System Lua Lub*
P1PK System P1 *These antigens are considered clinically significant as referenced by ANZSBT guidelines 1st Edition revised January 2020; Table 2.2; The clinical significance of red cell alloantibodies and selecting blood for transfusion
What is the difference between Monoclonal and Polyclonal phenotyping reagents?
Both monoclonal and polyclonal antisera are used in blood banks to detect blood group antigens. Monoclonal reagents are derived and manufactured in a laboratory from a single cell clone and are specific to a particular epitope of a single antigen. Polyclonal reagents however are derived from an immunised plasma source and therefore bind to many different epitopes of a single antigen.
What is a Red Blood Cell (RBC) Genotype?
In general terms, a genotype refers to different alleles, or variant forms of a gene. Diagnostic RBC genotyping is an in vivo diagnostic test intended for the molecular determination of allelic variants in order to predict the RBC phenotype.
What is the difference between a Phenotype and Genotype?
The main difference between a RBC phenotype and RBC genotype is that a phenotype determines the antigens present on a red cells with serology methods whilst a RBC genotype looks at the genomic DNA of a patient to determine the antigen genotype and predict the expected phenotype.
Common incidences where a RBC genotype is needed over a RBC phenotype include;
- when a patient’s red blood cell antigens cannot be reliably phenotyped due to recent history of receiving blood transfusion.
- Prior to commencement of interfering drug therapies such as anti-CD47 or Anti-CD38
- To investigate genetic changes such as partial antigens that may explain alloantibodies but positive phenotyping.
- In rare cases when uncommon antibodies form, and commercial antisera are not available.
What is Quality Control in Immunohaematology
Quality Control (QC) may be defined as the management of the testing process.
It involves controlling the testing environment to ensure that tests are reproducible, accurate and sensitive. QC of reagents should be a regular part of blood bank laboratory testing and should encompass tests for avidity, specificity and sensitivity. Reagent QC should challenge the limitations of the reagent and always include controls that give both positive and negative reactions. Controls must be specific and sensitive and reflect the patient population being tested. In most cases positive controls should be weak to demonstrate that tests meet sensitivity requirements. Controls should be tested in parallel with patient samples and control products should be designed to test the inherent variables present throughout the entire testing procedure.