OTHER BLOOD GROUP SYSTEMS PART 1 (LEWIS, P, LUKE)

Question 1

Antigens in the Lewis blood group system do not develop as integral parts of the red blood cell (RBC) membrane. Instead, they are adsorbed by the [?].

Answer 1

RBCs from the surrounding plasma

Question 2

• The amount of Lewis antigen varies and depends on:

• Individual’s (?).
• Gradual development of (?).
• Influence of (?) genes.

Answer 2

ABO phenotype and age
Lewis Ag
H, Se, and Le

Question 3

• Lewis antigen expression may decrease dramatically during.

Answer 3

pregnancy

Question 4

Lewis

The most common phenotypes include:

Answer 4

• Le(a+b−)
• Le(a−b+)
• Le(a+b+)
• Le(a−b−)

Question 5

• Most neonates typically type as [?] regardless of inherited Lewis genes.

Answer 5

Le(a−b−)

Question 6

• Usually IgM but may contain IgG components.

Answer 6

Anti-Lea antibodies

Question 7

• React best at room temperature but may also react at 37°C.

Answer 7

Anti-Lea antibodies

Question 8

• Can bind complement and trigger in vitro hemolysis, potentially causing hemolytic transfusion reactions (HTR).

Answer 8

Anti-Lea antibodies

Question 9

• Anti-Lea or Anti-Leb

is enhanced by enzyme treatment.

Answer 9

Anti-Lea or Anti-Leb

Question 10

• Usually IgM and react best at room temperature.

Answer 10

Anti-Leb antibodies

Question 11

• Bind complement poorly.

Answer 11

Anti-Leb antibodies

Question 12

• Activity is enhanced by enzyme treatment.

Answer 12

Anti-Leb antibodies

Question 13

• Lewis antibodies may transiently appear during pregnancy in [?] women but disappear after delivery.

Answer 13

Le(a−b−)

Question 14

• Both [?] react with most cells on routine RBC panels.

Answer 14

anti-Lea and anti-Leb antibodies

Question 15

• Lewis substance can neutralize these antibodies, allowing the detection of other antibodies present.

Answer 15

anti-Lea and anti-Leb antibodies

Question 16

• Poorly developed at birth: Lewis antigens are not fully developed in.

Answer 16

newborns

Question 17

• Reversibly adsorbed onto red cells from plasma: can attach to the surface of red blood cells from the plasma and can be removed under certain conditions.

Answer 17

Lewis antigens

Question 18

• Not found on cord blood or newborn red cells (Le(a-b-)): Cord blood and newborn red cells typically lack the antigens initially.

Answer 18

Lewis

Question 19

• Lewis glycolipids detectable in plasma after approximately [?]: It takes around 10 days after birth for Lewis glycolipids tobecome detectable in the plasma.

Answer 19

10 days of life

Question 20

• Transformation of Lewis phenotype after [?]: Individuals may undergo changes in their Lewis phenotype after birth, transitioning from Le(a-b-) to the true phenotype, which is Le(a-b-).

Answer 20

birth

Question 21

• Decrease in expression during [?]: Expression of Lewis antigens on red blood cells can decrease in pregnant women, leading to a Le(a-b-) phenotype during pregnancy.

Answer 21

pregnancy

Question 22

Do not exhibit dosage effects in serologic reactions. This means that the presence of one or two copies of the gene does not affect the strength of the antigen reaction in serological testing.

Answer 22

Lewis antigens

Question 23

• Naturally occurring: are typically present in the serum without prior sensitization to foreign antigens.

Answer 23

Lewis antibodies

Question 24

• Predominantly IgM: These antibodies are primarily of the IgM class, which means they are relatively large and can agglutinate red blood cells efficiently.

Answer 24

Lewis

Question 25

• May cause in vivo hemolysis

Answer 25

Lewis antibodies

Question 26

•Synthesis and Structure: Lewis blood group antigens are produced by tissue cells and secreted into body fluids.Those in secretions are [?], while those absorbed onto red blood cell membranes are [?].

Answer 26

glycoproteins glycolipids

Question 27

•Genetic Basis: The Le gene codes for [?], necessary for Lea expression, while Le and Se genes are needed for Leb expression.

Answer 27

L-fucosyltransferase

Question 28

•Antigen Formation: Lea antigen is formed by adding [?] to a specific carbon of [?], while Leb antigen requires a second addition of L-fucose to a specific carbon of N-acetylglucosamine.

Answer 28

L-fucose N-acetylglucosamine

Question 29

•Phenotypes andSecretor Status: Le(a-b-) individuals are [?] and have only [?], while Le(a-b+) individuals are [?] and have both [?].

Answer 29

ABH nonsecretors; Lea substance ABH secretors; Lea and Leb substances

Question 30

The most common phenotype in both white and black populations is [?], with the [?] being more common among blacks.

Answer 30

Le(a-b-) lele genotype

Question 31

are poorly expressed at birth and do not exhibit dosage effects in serologic reactions.

Answer 31

Lewis antigens

Question 32

•Antibodies: Lewis antibodies, typically [?] and [?], can bind [?] and are enhanced by [?].

Answer 32

IgM; naturally occurring complement; enzymes

Question 33

Lewis substance in [?] can neutralize these antibodies. They are frequently encountered in [?] but are not considered significant in [?].

Answer 33

secretions pregnant women transfusion medicine

Question 34

• Traditionally, the P blood group included [?].

Answer 34

P, P1, Pk antigens, and later, Luke (LKE)

Question 35

• In the [?] nomenclature:

Answer 35

International Society of Blood Transfusion (ISBT)

Question 36

are assigned to the P1Pk blood group system

Answer 36

• P1 and Pk antigens

Question 37

is assigned to the globoside blood group system

Answer 37

• P antigen

Question 38

(003, P1PK).

Answer 38

• P1 and Pk antigens

Question 39

(028, symbol GLOB).

Answer 39

• P antigen

Question 40

are assigned to the Globoside Collection

Answer 40

• LKE and PX2

Question 41

(029, GLOB)

Answer 41

• LKE and PX2

Question 42

• The P1PK gene is located at chromosome

Answer 42

22q11.2.

Question 43

• The Pgene is located at chromosome

Answer 43

3q26.1.

Question 44

• Biosynthetic Pathways: There are two distinct pathways for synthesizing P blood group antigens.

Answer 44

• Pathway on the left results in paragloboside and P1 antigens • Pathway on the right leads to the production of the globoside series: Pk, P, and LKE antigens.

Question 45

• Common precursor:

Answer 45

Lactosylceramide (or Gb2, also known as ceramide dihexose or CDH).

Question 46

is also a precursor for the ABH antigens.

Answer 46

Paragloboside

Question 47

• Pathway on the right leads to the production of the globoside series:

Answer 47

Pk, P, and LKE antigens.

Question 48

: Common phenotype (about 75% of the population) with both P and P1 antigens. is well developed at birth is poorly developed at birth.

Answer 48

1.P1 Phenotype P antigen P1 antigen

Question 49

: Common phenotype, individuals have only P antigen.

Answer 49

2.P2 Phenotype

Question 50

: Very rare, individuals have both P1 and Pk antigens.

Answer 50

3.Pk1 Phenotype

Question 51

: Very rare, individuals have both P2 and Pk antigens.

Answer 51

4.Pk2 Phenotype

Question 52

: Extremely rare, RBCs are negative for P, P1, and Pk antigens.

Answer 52

5. p Phenotype

Question 53

: Naturally occurring, cold-reacting, IgM antibodies often found in individuals with P2 phenotype.

Answer 53

1.Anti-P1 Antibodies

Question 54

Rarely react at temperatures higher than room temperature, but they can bind complement.

Answer 54

1.Anti-P1 Antibodies

Question 55

Not associated with hemolytic disease of the newborn (HDN) and rarely cause hemolytic transfusion reactions (HTR).

Answer 55

1.Anti-P1 Antibodies

Question 56

Produced by individuals with Pk1 or Pk2 phenotypes, can cause severe HTR.

Answer 56

2. Anti-P Antibodies

Question 57

[?], also known as the Donath-Landsteiner antibody

Answer 57

Autoanti-P

Question 58

is a cold-reacting antibody associated with paroxysmal cold hemoglobinuria (PCH).

Answer 58

Autoanti-P

Question 59

3.Other Antibodies: occur only rarely.

Answer 59

Anti-PP, anti-Pk, and anti-p antibodies

Question 60

Discovered in 1965 by Tippett et al. in a patient with Hodgkin’s lymphoma.

Answer 60

Luke (LKE) Antigen and Antibody

Question 61

Luke (LKE) Antigen and Antibody Divides the population into three phenotypes:

Answer 61

Luke+, Luke(w), and Luke-.

Question 62

Approximately [?] of individuals are Luke+, [?] are weakly positive (Luke(w)), and [?] are Luke-.

Answer 62

84% 14% 2%

Question 63

Although it segregates independently of the P blood group, it is phenotypically related because the antibody reacts with most RBCs except those with rare P1, P2, p, and Pk phenotypes.

Answer 63

LKE

Question 64

Individuals with the [?] are always Luke- (or--LKE-).

Answer 64

p and Pk phenotypes

Question 65

LKE+ individuals can be either

Answer 65

P1 or P2.

Question 66

The Pk antigen is more strongly expressed on [?] than on LKE- RBCs.

Answer 66

LKE+ RBCs

Question 67

Only five examples of human [?] are known.

Answer 67

alloanti-LKE

Question 68

The original antibody was a saline agglutinin reacting best at-- 4°C.

Answer 68

Luke (LKE) Antibody

Question 69

It became a potent hemolysin with enzyme methods and additional complement.

Answer 69

Luke (LKE) Antibody

Question 70

Other examples of [?] are much weaker and clinically insignificant.

Answer 70

alloanti-LKE

Question 71

have been associated with parasitic infections.

Answer 71

Anti-P1 antibodies

Question 72

• Antibodies such as [?] have been linked toearly abortions.

Answer 72

anti-PP1Pk or anti-P

Question 73

are implicated in causing PCH

Answer 73

• Autoanti-P antibodies

Question 74

a condition characterized by the sudden destruction of red blood cells in response to cold temperatures.

Answer 74

Paroxysmal Cold Hemoglobinuria (PCH)

Question 75

• Certain strains of Escherichia coli associated with urinary tract infections adhere to [?] on uroepithelial cells. This adherence facilitates their ascent in a ladderlike fashion through the urinary tract.

Answer 75

P1 and/or Pk glycolipids

Question 76

• Streptococcus suis, a bacterium that can cause meningitis and septicemia in humans, binds exclusively to

Answer 76

Pk antigen.

Question 77

• Toxins secreted by pathogens such as Shigella dysenteriae, Vibrio cholerae, Vibrio parahaemolyticus, and some pathogenic strains of E. coli have binding specificity for the [?].

Answer 77

Gal(α1-4)Gal(β1-4) moiety found in P1 and Pk antigens

Question 78

• Human parvovirus B19 uses [?] as a receptor for infection.

Answer 78

globoside

Question 79

•The P blood group comprises the antigens [?], which are biochemically related.

Answer 79

P, P1, Pk, andLKE

Question 80

•There's a biochemical relationship between

Answer 80

the P blood group antigens and the ABH and I antigens.

Question 81

•Produced by all p individuals early in life without RBC sensitization.

Answer 81

Anti-PP1PkAntibody

Question 82

•Reacts with all RBCs except those of other p individuals.

Answer 82

Anti-PP1PkAntibody

Question 83

•Antibodies may be a mixture of IgM and IgG, efficiently bind complement, and may demonstrate in-vitro hemolysis.

Answer 83

Anti-PP1PkAntibody

Question 84

• Found as a naturally occurring alloantibody in the sera of all p

Answer 84

Anti-P Antibody

Question 85

• Usually caused by autoantibodies demonstrating anti-P specificity.

Answer 85

Paroxysmal Cold Hemoglobinuria (PCH)

Question 86

PCH autoantibodies are (?) hemolysins typically detectable only by the Donath-Landsteiner test.

Answer 86

IgG biphasic