ICAM4

Last updated
Intercellular Adhesion Molecule-4 (Landsteiner-Wiener blood group system)
Identifiers
SymbolICAM-4
Alt. symbolsLW
NCBI gene 3386
HGNC 5347
OMIM 111250
RefSeq NM_001039132
UniProt Q14773
Other data
Locus Chr. 19 p13.2-cen
Search for
Structures Swiss-model
Domains InterPro

The LW blood system was first described by Landsteiner and Wiener in 1940. [1] It was often confused with the Rh system, not becoming a separate antigen system until 1982. The LW and RhD antigens are genetically independent though they are phenotypically related and the LW antigen is expressed more strongly on RhD positive cells than on RhD negative cells. In most populations, the antithetical LW antigens, LWa and LWb are present as very high and very low frequency, respectively. [1] [2] [3]

Contents

Genomics

The LW locus is located on the short arm of chromosome 19 (19p13.3). [1]

Molecular biology

LW antigens reside on a 40- to 42-kiloDalton red cell membrane glycoprotein named CD242. [2] The LW glycoprotein has recently been renamed ICAM-4 due to its similarity to intercellular adhesion molecule, although exactly which integrins bind to ICAM-4 is subject to controversy.

The function of ICAM-4 is not fully understood but appears to be restricted to erythroid cells. During in vitro erythropoesis, LW appears at either the erythroid colony forming stage or later at the proerythroblast stage. A vital part of erythropoesis is the clustering of erythroblasts around bone marrow macrophages to form erythroblastic islands. The erythroblast is then able to remove its nucleus, which is in turn ingested and broken down by the macrophages, to become a mature erythrocyte. During this process ICAM-4 binds to VLA-4, an erythroblast binding site, on adjacent erythroblasts and to αv integrins on macrophages to help stabilise the erythroblastic islands. The binding of red cells to macrophages in the spleen by ICAM-4 could also play a part in the removal of senescent red cells. [1] [2] [3]

Despite the functional aspects of ICAM-4, its apparent absence in LW(a-b-) and Rhnull phenotypes does not appear to lead to any obvious pathological effects. ICAM-4 expression is elevated on sickle red cells and its binding to αv integrins on the endothelial cells may cause the pain associated with sickle cell crises. [1] [2]

Auto anti-LW is not uncommon as an autoantibody but usually presents with transient suppression of the LW antigen in genetically LW+ individuals, and so appears to be an alloantibody. True alloanti-LW is a very rare occurrence, with only two known examples of alloanti-LWab, produced by patients with an LW(a-b-) phenotype. Anti-LW can be present as a clinically insignificant autoantibody and not be associated with increased red cell destruction. Anti-LW has also been associated with cases of warm type autoimmune haemolytic anaemia; Philip Levine suggested that it was the most common antibody in cases of AIHA with a positive Coombs test. [1] [4] [5]

Transfusion medicine

Haemolytic disease of the newborn (HDFN) due to alloanti-LW is described as mild and very rare, even the very potent anti-LWab of one known patient caused minimal evidence of HDFN in her three pregnancies. [6] To date auto anti-LW has only been implicated as the cause of one case of HDFN. [7]

Related Research Articles

Rh disease is a type of hemolytic disease of the fetus and newborn (HDFN). HDFN due to anti-D antibodies is the proper and currently used name for this disease as the Rh blood group system actually has more than 50 antigens and not only the D-antigen. The term "Rh Disease" is commonly used to refer to HDFN due to anti-D antibodies, and prior to the discovery of anti-Rho(D) immune globulin, it was the most common type of HDFN. The disease ranges from mild to severe, and occurs in the second or subsequent pregnancies of Rh-D negative women when the biologic father is Rh-D positive.

<span class="mw-page-title-main">Hemolytic disease of the newborn</span> Fetal and neonatal alloimmune blood condition

Hemolytic disease of the newborn, also known as hemolytic disease of the fetus and newborn, HDN, HDFN, or erythroblastosis foetalis, is an alloimmune condition that develops in a fetus at or around birth, when the IgG molecules produced by the mother pass through the placenta. Among these antibodies are some which attack antigens on the red blood cells in the fetal circulation, breaking down and destroying the cells. The fetus can develop reticulocytosis and anemia. The intensity of this fetal disease ranges from mild to very severe, and fetal death from heart failure can occur. When the disease is moderate or severe, many erythroblasts are present in the fetal blood, earning these forms of the disease the name erythroblastosis fetalis.

The direct and indirect Coombs tests, also known as antiglobulin test (AGT), are blood tests used in immunohematology. The direct Coombs test detects antibodies that are stuck to the surface of the red blood cells. Since these antibodies sometimes destroy red blood cells they can cause anemia; this test can help clarify the condition. The indirect Coombs test detects antibodies that are floating freely in the blood. These antibodies could act against certain red blood cells; the test can be carried out to diagnose reactions to a blood transfusion.

<span class="mw-page-title-main">ABO blood group system</span> Classification of blood types

The ABO blood group system is used to denote the presence of one, both, or neither of the A and B antigens on erythrocytes. For human blood transfusions, it is the most important of the 44 different blood type classification systems currently recognized by the International Society of Blood Transfusions (ISBT) as of December 2022. A mismatch in this, or any other serotype, can cause a potentially fatal adverse reaction after a transfusion, or an unwanted immune response to an organ transplant. The associated anti-A and anti-B antibodies are usually IgM antibodies, produced in the first years of life by sensitization to environmental substances such as food, bacteria, and viruses.

<span class="mw-page-title-main">ICAM-1</span> Mammalian protein found in Homo sapiens

ICAM-1 also known as CD54 is a protein that in humans is encoded by the ICAM1 gene. This gene encodes a cell surface glycoprotein which is typically expressed on endothelial cells and cells of the immune system. It binds to integrins of type CD11a / CD18, or CD11b / CD18 and is also exploited by rhinovirus as a receptor for entry into respiratory epithelium.

In ABO hemolytic disease of the newborn maternal IgG antibodies with specificity for the ABO blood group system pass through the placenta to the fetal circulation where they can cause hemolysis of fetal red blood cells which can lead to fetal anemia and HDN. In contrast to Rh disease, about half of the cases of ABO HDN occur in a firstborn baby and ABO HDN does not become more severe after further pregnancies.

Hemolytic disease of the newborn (anti-Kell1) is the second most common cause of severe hemolytic disease of the newborn (HDN) after Rh disease. Anti-Kell1 is becoming relatively more important as prevention of Rh disease is also becoming more effective.

The Kidd antigen system are proteins found in the Kidd's blood group, which act as antigens, i.e., they have the ability to produce antibodies under certain circumstances. The Jk antigen is found on a protein responsible for urea transport in the red blood cells and the kidney. They are important in transfusion medicine. People with two Jk(a) antigens, for instance, may form antibodies against donated blood containing two Jk(b) antigens. This can lead to hemolytic anemia, in which the body destroys the transfused blood, leading to low red blood cell counts. Another disease associated with the Jk antigen is hemolytic disease of the newborn, in which a pregnant woman's body creates antibodies against the blood of her fetus, leading to destruction of the fetal blood cells. Hemolytic disease of the newborn associated with Jk antibodies is typically mild, though fatal cases have been reported.

<span class="mw-page-title-main">Rh blood group system</span> Human blood group system involving 49 blood antigens

The Rh blood group system is a human blood group system. It contains proteins on the surface of red blood cells. After the ABO blood group system, it is the most likely to be involved in transfusion reactions. The Rh blood group system consisted of 49 defined blood group antigens in 2005. As of 2023, there are over 50 antigens among which the five antigens D, C, c, E, and e are the most important. There is no d antigen. Rh(D) status of an individual is normally described with a positive (+) or negative (−) suffix after the ABO type. The terms Rh factor, Rh positive, and Rh negative refer to the Rh(D) antigen only. Antibodies to Rh antigens can be involved in hemolytic transfusion reactions and antibodies to the Rh(D) and Rh antigens confer significant risk of hemolytic disease of the fetus and newborn

<span class="mw-page-title-main">Integrin beta 2</span> Mammalian protein found in Homo sapiens

In molecular biology, CD18 is an integrin beta chain protein that is encoded by the ITGB2 gene in humans. Upon binding with one of a number of alpha chains, CD18 is capable of forming multiple heterodimers, which play significant roles in cellular adhesion and cell surface signaling, as well as important roles in immune responses. CD18 also exists in soluble, ligand binding forms. Deficiencies in CD18 expression can lead to adhesion defects in circulating white blood cells in humans, reducing the immune system's ability to fight off foreign invaders.

Macrophage-1 antigen is a complement receptor ("CR3") consisting of CD11b and CD18.

<span class="mw-page-title-main">Leukocyte extravasation</span>

Leukocyte extravasation is the movement of leukocytes out of the circulatory system and towards the site of tissue damage or infection. This process forms part of the innate immune response, involving the recruitment of non-specific leukocytes. Monocytes also use this process in the absence of infection or tissue damage during their development into macrophages.

Hemolytic disease of the newborn (anti-RhE) is caused by the anti-RhE antibody of the Rh blood group system. The anti-RhE antibody can be naturally occurring, or arise following immune sensitization after a blood transfusion or pregnancy.

<span class="mw-page-title-main">ICAM3</span> Mammalian protein found in Homo sapiens

Intercellular adhesion molecule 3 (ICAM3) also known as CD50, is a protein that in humans is encoded by the ICAM3 gene. The protein is constitutively expressed on the surface of leukocytes, which are also called white blood cells and are part of the immune system. ICAM3 mediates adhesion between cells by binding to specific integrin receptors. It plays an important role in the immune cell response through its facilitation of interactions between T cells and dendritic cells, which allows for T cell activation. ICAM3 also mediates the clearance of cells undergoing apoptosis by attracting and binding macrophages, a type of cell that breaks down infected or dying cells through a process known as phagocytosis, to apoptotic cells.

<span class="mw-page-title-main">CD47</span> Protein-coding gene in humans

CD47 also known as integrin associated protein (IAP) is a transmembrane protein that in humans is encoded by the CD47 gene. CD47 belongs to the immunoglobulin superfamily and partners with membrane integrins and also binds the ligands thrombospondin-1 (TSP-1) and signal-regulatory protein alpha (SIRPα). CD-47 acts as a don't eat me signal to macrophages of the immune system which has made it a potential therapeutic target in some cancers, and more recently, for the treatment of pulmonary fibrosis.

The following outline is provided as an overview of and topical guide to immunology:

This page is currently under construction.

Rh factor testing, also known as Rhesus factor testing, is the procedure of determining the rhesus D status of an individual.

<span class="mw-page-title-main">Blood compatibility testing</span> Testing to identify incompatibilities between blood types

Blood compatibility testing is conducted in a medical laboratory to identify potential incompatibilities between blood group systems in blood transfusion. It is also used to diagnose and prevent some complications of pregnancy that can occur when the baby has a different blood group from the mother. Blood compatibility testing includes blood typing, which detects the antigens on red blood cells that determine a person's blood type; testing for unexpected antibodies against blood group antigens ; and, in the case of blood transfusions, mixing the recipient's plasma with the donor's red blood cells to detect incompatibilities (crossmatching). Routine blood typing involves determining the ABO and RhD type, and involves both identification of ABO antigens on red blood cells and identification of ABO antibodies in the plasma. Other blood group antigens may be tested for in specific clinical situations.

<span class="mw-page-title-main">Antibody elution</span> Laboratory procedure

An antibody elution is a clinical laboratory diagnostic procedure which removes sensitized antibodies from red blood cells, in order to determine the blood group system antigen the antibody targets. An antibody elution is deemed necessary when antibodies of the immunoglobulin class G (IgG) are found sensitized (bound) to peripheral red cells collected from a blood product transfusion recipient. IgG antibodies are detected using an assay known as the direct antiglobulin test.

References

  1. 1 2 3 4 5 6 Daniels G (2002). Human Blood Groups (2nd ed.). Malden, Mass.: Blackwell Science. ISBN   978-0-632-05646-0. OCLC   48435824.
  2. 1 2 3 4 Klein HG, Mollison PL, Anstee DJ (2005). Mollison's Blood Transfusion in Clinical Medicine (11th ed.). Oxford: Blackwell. ISBN   978-0-632-06454-0. OCLC   60348837.
  3. 1 2 Hoffbrand AV, Pettit JE, Moss PA (2006-10-31). Essential Haematology (5th ed.). Oxford: Wiley-Blackwell. ISBN   978-1-4051-3649-5. OCLC   70402356.
  4. ↑ Gorst DW, Rawlinson VI, Merry AH, Stratton F (February 1980). "Positive direct antiglobulin test in normal individuals". Vox Sanguinis. 38 (2): 99–105. doi:10.1111/j.1423-0410.1980.tb02337.x. OCLC   1769301. PMID   6967653. S2CID   34575224.
  5. ↑ Vos GH, Petz LD, Garratty G, Fudenberg HH (September 1973). "Autoantibodies in acquired hemolytic anemia with special reference to the LW system". Blood. 42 (3): 445–53. doi: 10.1182/blood.V42.3.445.445 . OCLC   1536582. PMID   4737659.
  6. ↑ Daniels G, Poole J, de Silva M, Callaghan T, MacLennan S, Smith N (October 2002). "The clinical significance of blood group antibodies". Transfusion Medicine. 12 (5): 287–95. doi:10.1046/j.1365-3148.2002.00399.x. OCLC   26133630. PMID   12383334. S2CID   32354754.
  7. ↑ Davies J, Day S, Milne A, Roy A, Simpson S (August 2009). "Haemolytic disease of the foetus and newborn caused by auto anti-LW". Transfusion Medicine. 19 (4): 218–9. doi: 10.1111/j.1365-3148.2009.00936.x . OCLC   26133630. PMID   19706140. S2CID   205389513.
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