Bloodbanking Lecture 3: BGS that Produce Cold Antibodies (P, I, MNS) - Resistant to Ficin, Papain, Dithiothreitol (DT
Glycine-Acid EDTA
BGS that Produce Cold Antibodies = PILMNS
- P BGS Biochemistry of P Antigens:
- I BGS - RBCs and Plasma = Exist as Glycosphinolipids
- Lewis BGS - Hydatid Cyst Fluid = Exist as Glycoproteins
- MNS (referred to as 1 BGS but only Anti-M is a Cold Antibody) - Common Precursor Substance of All P Antigen
(Gb2 or Ceramide Dihexose)
P Blood Group System
o Gives rise to formation of P1 and Paraglobosi
- Not a Single Blood Group System but 3 Systems Interrelated to One Another:
o Paragloboside = Type 2 Precursor for A
o P1 Pk = ISBT 003
Antigens
o P [GLOB] = ISBT 028
o Also gives rise to Pk, P and Luke Antigens
o Luke [LKE] and PX2 [GLOB Collection] = ISBT 209
- 2 Distinct Biosynthetic Pathways of P Antigens:
- Introduced by Landsteiner and Levine in 1927
o Lactosylceramide (Gb2) forms Lactotriaosyl
- Genes:
Paragloboside which can give rise to both P
o P1 Pk = Chromosome 22
o Lactosylceramide (Gb2) + 4-Alpha-Galact
o P = Chromosome 3
Antigen
- Antigens:
Pk Antigen + 3-Beta-N-Acetylgalacto
o P1
Antigen Globoside
o P
Luke Antigen is also formed from thi
o Pk = AKA Globotriaosylceramide (Gb3) = Converted to P Antigens
mechanism is yet to be known
o Luke (LKE)
***4-Alpha-Galactosyltransferase
- Found in RBCs, Plasma and Other Tissues but Not Found in Secretions
- Gb3 Synthase or Pk Synthase
- P1, P and Pk = Found on RBCs, Lymphocytes, Granulocytes and Monocytes
- Forms Pk Antigen from Precursor Substance
- P = Found on Platelets, Epithelial Cells and Fibroblasts
***3-Beta-N-Acetylgalactosaminyltrasferase
- Gb4 Synthase
, - Coded by B3GALNT1 Gene - Deteriorates Rapidly on Storage
- Converts Pk to P Antigen o Older RBCs = May Produce False Negative Re
- Also found in Hydatid Cyst Fluid caused by Echinoc
Patients with Fascioliasis (Bovine Liver Fluke Disea
P BGS Phenotypes: (Memorize)
Anti-P1
Possible Antibodies
Phenotypes Antigens - Naturally Occurring IgM found most often in
Produced
Phenotype)
P1 P1 and P Antigens None
- Weak, Cold-Reactive Saline Agglutinin that Optimally
P2 P Antigen Only Anti-P1
- Not Clinically Significant
p No P, P1 nor Pk Anti-PP1Pk
- Never causes HDFN but may cause Occasional HT
P1k P1 and Pk Antigens Anti-P
o Cannot cause HDFN since:
P2k Pk Only Anti-P1 and Anti-P
IgM Type = Cannot Cross Placenta
***Note that Pk is no longer mentioned in P1 and P2 since it is the precursor of P
P1 Antigen = Poorly Expressed at Birt
Antigens so it is understood to be present if P is present.
- If Anti-P1 is suspected, detect by Incubation at Room
***P2 Phenotype = Capable of Producing Anti-P1 since it does not have P1 Antigens Pretreatment of RBCs with Enzymes
***P Null (p Phenotype) = Slightly More Common in Japan, North Sweden and - Neutralized or Inhibited by Hydatid Cyst Fluid (wh
in an Amish Group in Ohio Antigens) in the lab to reveal other significant antibodi
P1 Antigens Anti-PP1Pk
- Poorly expressed at birth and may take up to 7 years to be fully - Formerly known as Anti-Tja
expressed - First described in serum of Mrs. Jay suffe
- Antigen strength varies from one individual to another (Adenocarcinoma)
o Some may be P1+s (Strong) or P1+w (Weak) - Produced by p individuals and is Naturally Occurrin
o Blacks have stronger expression of P1 than Whites - Each component (Anti-P, Anti-P1 and Anti-Pk) may
- Inhibitor Lutheran Gene = In(lu) = Inhibits Expression of P1 Antigens = Adsorption
Inheritance of this gene leads to P1- even if person is originally P1+ - May be of IgM or IgG Forms
Glycine-Acid EDTA
BGS that Produce Cold Antibodies = PILMNS
- P BGS Biochemistry of P Antigens:
- I BGS - RBCs and Plasma = Exist as Glycosphinolipids
- Lewis BGS - Hydatid Cyst Fluid = Exist as Glycoproteins
- MNS (referred to as 1 BGS but only Anti-M is a Cold Antibody) - Common Precursor Substance of All P Antigen
(Gb2 or Ceramide Dihexose)
P Blood Group System
o Gives rise to formation of P1 and Paraglobosi
- Not a Single Blood Group System but 3 Systems Interrelated to One Another:
o Paragloboside = Type 2 Precursor for A
o P1 Pk = ISBT 003
Antigens
o P [GLOB] = ISBT 028
o Also gives rise to Pk, P and Luke Antigens
o Luke [LKE] and PX2 [GLOB Collection] = ISBT 209
- 2 Distinct Biosynthetic Pathways of P Antigens:
- Introduced by Landsteiner and Levine in 1927
o Lactosylceramide (Gb2) forms Lactotriaosyl
- Genes:
Paragloboside which can give rise to both P
o P1 Pk = Chromosome 22
o Lactosylceramide (Gb2) + 4-Alpha-Galact
o P = Chromosome 3
Antigen
- Antigens:
Pk Antigen + 3-Beta-N-Acetylgalacto
o P1
Antigen Globoside
o P
Luke Antigen is also formed from thi
o Pk = AKA Globotriaosylceramide (Gb3) = Converted to P Antigens
mechanism is yet to be known
o Luke (LKE)
***4-Alpha-Galactosyltransferase
- Found in RBCs, Plasma and Other Tissues but Not Found in Secretions
- Gb3 Synthase or Pk Synthase
- P1, P and Pk = Found on RBCs, Lymphocytes, Granulocytes and Monocytes
- Forms Pk Antigen from Precursor Substance
- P = Found on Platelets, Epithelial Cells and Fibroblasts
***3-Beta-N-Acetylgalactosaminyltrasferase
- Gb4 Synthase
, - Coded by B3GALNT1 Gene - Deteriorates Rapidly on Storage
- Converts Pk to P Antigen o Older RBCs = May Produce False Negative Re
- Also found in Hydatid Cyst Fluid caused by Echinoc
Patients with Fascioliasis (Bovine Liver Fluke Disea
P BGS Phenotypes: (Memorize)
Anti-P1
Possible Antibodies
Phenotypes Antigens - Naturally Occurring IgM found most often in
Produced
Phenotype)
P1 P1 and P Antigens None
- Weak, Cold-Reactive Saline Agglutinin that Optimally
P2 P Antigen Only Anti-P1
- Not Clinically Significant
p No P, P1 nor Pk Anti-PP1Pk
- Never causes HDFN but may cause Occasional HT
P1k P1 and Pk Antigens Anti-P
o Cannot cause HDFN since:
P2k Pk Only Anti-P1 and Anti-P
IgM Type = Cannot Cross Placenta
***Note that Pk is no longer mentioned in P1 and P2 since it is the precursor of P
P1 Antigen = Poorly Expressed at Birt
Antigens so it is understood to be present if P is present.
- If Anti-P1 is suspected, detect by Incubation at Room
***P2 Phenotype = Capable of Producing Anti-P1 since it does not have P1 Antigens Pretreatment of RBCs with Enzymes
***P Null (p Phenotype) = Slightly More Common in Japan, North Sweden and - Neutralized or Inhibited by Hydatid Cyst Fluid (wh
in an Amish Group in Ohio Antigens) in the lab to reveal other significant antibodi
P1 Antigens Anti-PP1Pk
- Poorly expressed at birth and may take up to 7 years to be fully - Formerly known as Anti-Tja
expressed - First described in serum of Mrs. Jay suffe
- Antigen strength varies from one individual to another (Adenocarcinoma)
o Some may be P1+s (Strong) or P1+w (Weak) - Produced by p individuals and is Naturally Occurrin
o Blacks have stronger expression of P1 than Whites - Each component (Anti-P, Anti-P1 and Anti-Pk) may
- Inhibitor Lutheran Gene = In(lu) = Inhibits Expression of P1 Antigens = Adsorption
Inheritance of this gene leads to P1- even if person is originally P1+ - May be of IgM or IgG Forms
