Blood Groups: Lewis Antigens and Systems

<p>Leucine (B)</p> Signup and view all the answers

<p>They can be neutralized using commercially prepared Lewis substance (C)</p> Signup and view all the answers

<p>The Le gene and the Se gene interact to produce a unique phenotype (C)</p> Signup and view all the answers

<p>Codes for the production of fucosyltransferase enzyme 1 (A)</p> Signup and view all the answers

<p>By adsorbing Lewis substances from the plasma (B)</p> Signup and view all the answers

<p>It is soluble and found in plasma and saliva (D)</p> Signup and view all the answers

<p>It is the receptor for Helicobacter pylori (C)</p> Signup and view all the answers

<p>The Se gene (D)</p> Signup and view all the answers

<p>lele (A)</p> Signup and view all the answers

<p>Glycoproteins (A)</p> Signup and view all the answers

<p>It produces the ability to secrete H antigen (B)</p> Signup and view all the answers

<p>It does not produce any Lewis antigen (B)</p> Signup and view all the answers

<p>It converts the precursor material to Lea substance (A)</p> Signup and view all the answers

<p>Helicobacter pylori (D)</p> Signup and view all the answers

<p>They are soluble and found in plasma and saliva (C)</p> Signup and view all the answers

<p>Lele/Lele (C)</p> Signup and view all the answers

<p>They are easily destroyed or removed by enzymes (B)</p> Signup and view all the answers

<p>6% (D)</p> Signup and view all the answers

<p>They can cause in vivo and in vitro hemolysis (B)</p> Signup and view all the answers

<p>Glycine (C)</p> Signup and view all the answers

<p>The Le gene and the Se gene are codominant (C)</p> Signup and view all the answers

<p>Chromosome 2 (D)</p> Signup and view all the answers

<p>Ge2 (C)</p> Signup and view all the answers

<p>Leach phenotype (B)</p> Signup and view all the answers

<p>Cra (A)</p> Signup and view all the answers

<p>They are naturally occurring and can cause acute transfusion reactions (B)</p> Signup and view all the answers

<p>Wb (D)</p> Signup and view all the answers

<p>99.8% (D)</p> Signup and view all the answers

<p>A protein with cell adhesion properties (D)</p> Signup and view all the answers

<p>89% (C)</p> Signup and view all the answers

<p>IgG, red cell-stimulated (A)</p> Signup and view all the answers

<p>Short arm of the X chromosome (D)</p> Signup and view all the answers

<p>Found in the Marshall Islands and New Guinea (A)</p> Signup and view all the answers

<p>Immune adhesion (B)</p> Signup and view all the answers

<p>GIL (B)</p> Signup and view all the answers

<p>IgG and causes in vitro hemolysis (C)</p> Signup and view all the answers

<p>HLA-B7 (D)</p> Signup and view all the answers

<p>Occurring in 99.9% of the population (D)</p> Signup and view all the answers

<p>Exhibiting high-titer, low-avidity reactivity (B)</p> Signup and view all the answers

<p>Ina (C)</p> Signup and view all the answers

<p>JMH (C)</p> Signup and view all the answers

<p>Essential for Rh antigen expression (B)</p> Signup and view all the answers

<p>Ata (A)</p> Signup and view all the answers

The presence of the Le gene, along with the Se gene, determines whether an individual is Leb positive.

Lewis antigens are not directly synthesized on erythrocytes, but acquired from plasma.

Lewis antigens exist as soluble glycoproteins in secretions and glycolipids in plasma.

Antibodies like Anti-Lea and Anti-Leb are typically IgM and can trigger complement activation, leading to hemolysis.

The Le (a+b-) phenotype is found in approximately 22% of Whites and 23% of Blacks.

The Le (a-b+) phenotype occurs in approximately 72% of Whites and 55% of Blacks.

The Le (a-b-) phenotype is less common, occurring in about 6% of Whites and 22% of Blacks.

The Le (a+b+) phenotype is rare in both Whites and Blacks.

MN antigens are found on glycophorin A and differ in their amino acid composition (M: serine and glycine; N: leucine and glutamate).

Both M and N antigens are expressed equally if present, exhibiting codominance.

Both M and N antigens are easily destroyed by enzymes.

The system displays dosage effects, which are relevant in paternity testing.

This system includes high incidence antigens (Ge2, Ge3, Ge4) and low incidence antigens (Wb, Lsa, Ana, Dha), expressed on glycophorins C and D.

Antibodies like Anti-Ge2 and Anti-Ge3 are naturally occurring and can cause transfusion reactions.

The Cromer system has high incidence antigens such as Cra, Tca, Dra, and Esa.

Antibodies like anti-Wb and anti-Lsa are IgG and implicated in transfusion reactions but not in HDFN.

Dia antigens have significance in studying Mongolian ancestry and are located on the anion exchange molecule AE-1.

Both anti-Dia and anti-Dib are IgG and react in the indirect antiglobulin test.

Anti-Wra antibodies are IgG, immune-stimulated, and react in blood group testing.

The Xga antigen has different frequencies between sexes, with 89% of females and 66% of males expressing it.

Anti-Sc antibodies can cause transfusion reactions.

High-frequency antibodies like Anti-Ch and Anti-Rga are generally clinically insignificant.

Anti-Vel antibodies can cause severe transfusion reactions.

High-incidence antigens are found in over 99.9% of the population, examples include Augustine and Vel.

Low-incidence antigens occur in less than 1% of the population; examples include Wright (Swa) and By (Mta).

Clinically significant antibodies typically react in indirect testing.

Naturally occurring antibodies are often IgM, while immune-stimulated antibodies tend to be IgG.

Some antibodies can bind complement and cause hemolysis, while others are labile or enhance in response to infections.

Warm antibodies react at body temperature and are significant in transfusions.

Cold antibodies react at lower temperatures and can indicate certain conditions like infectious mononucleosis.