Bloodbanking Lecture 4: Kell, Kidd, Duffy and Lutheran BGS
Systems that Produce Warm Antibodies = Kell, Kidd, Duffy, Lutheran 2. Kpa and Kpb
o Kpa = Low Prevalence Antigen (2% of W
Kell Blood Group System (ISBT 006)
Reduced Amount of Kell Glycoprotein in RB
- Consists of 32 High Prevalence and Low Prevalence Antigens
o Kpb = High Prevalence Antigen (99.9% of Po
- 1st Blood Group to be Discovered after Introduction of AHG Testing
o Kpc = Very Rare
- Identified in the serum of Mrs. Kelleher
- All Kell Antigens can ONLY BE FOUND IN RBCs o Named as Kp since first found in Mrs. Penney
- Encoded on Chromosome 7 3. Jsa and Jsb
o KEL Gene = 19 Coding Exons o Jsa = Low Prevalence Antigen (20% of Black
o Mutations in Kell Gene = K0 or Kell Null o Jsb = High Prevalence Antigen
o Named as Js since first found in Mr. John Sutt
Antigens:
4. Kx Antigen (ISBT 019)
1. K and k
o Encoded on X Chromosome (Chrom
o Antithetical Antigens
Chromosome)
o K = Kell = Low Prevalence Antigen (Less than 9% of Population)
o XK1 Gene
o k = Cellano = High Prevalence Antigen (More than 90% of
o Not Part of the Kell Blood Group System but
Population)
Kell Antigens
o Well developed at birth:
o Found in RBCs and Other Tissues such
K = 10 Weeks of Gestation
Organs, Heart and Skeletal Muscle
k = 7 Weeks of Gestation
o Present in All Individuals
o K Antigen is VERY IMMUNOGENIC and is SECOND ONLY TO D
o Kell Antigen Expression depends upon
ANTIGEN in stimulating antibody production.
Antigen
o Absence of Kx Antigen = McLeod Phenotyp
, ***If Kell Antigens are not present, there is no cloud to cov
their detection easier and appear increased in number.
Biochemistry of Kell Antigens and Kx Antigens:
Kell Glycoproteins Anti-K
- RBC Membrane Glycoproteins where Kell Antigens are attached - IgG that reacts well at AHG Phase and may also re
- Member of the Neprilysin (M13) Family of Zinc Endopeptidases Phase
- Produced via Exposure through Pregnancy and Tran
Kell Antigens (K/k, Kpa/Kpb and Jsa/Jsb)
- Anti-K is the 3rd Most Common Antibody Seen in B
- Have 15 Cysteine Amino Acids which forms Disulfide Bonds
o 1st is ABO Antibodies
o Makes them Resistant to Enzymes but Very Sensitive to Sulfhydryl
o 2nd is Rh Antibodies
Reagents
- IgM Anti-K = Very Rare = Associated w/ Bacter
- Examples of Sulfhydryl Reagents = 2-Mercaptoethanol, Dithriothreitol, 2-
0125:B15) which was said to have a Somatic K-Like
Aminoethylisothiouronium Bromide (2-AET) and ZZAP
o It is interesting to note that the IgM Anti-K dis
Kx Antigen of the patient.
- Spans the RBC Membrane 10x and is an RBC Transport Protein - Most Reliable Method of Detecting Anti-K = INDIR
- Kx Antigen is linked to Kell Glycoprotein via a Single Disulfide Bond = TEST
Forms Km Antigen - Polyethylene Glycol = Increases Reactivity of Anti
- Resistant to Sulfhydryl Reagents - RBC Destruction is usually Extravascular via Splenic
***The Kx Antigen is always present on RBC Membranes but sometimes cannot be - Causes Severe HTR and Severe HDFN w/ Fetal Ane
detected or are only in small amounts because the Disulfide Bonds of Kell Anti-Kpa and Anti-Jsa
Antigens form a cloud which masks detection of the Kx Antigen and appear - Rare since they are antibodies to Low Prevalence Ant
decreased in number. - Most Often Detected through Unexpected Incompa
Cases of HDFN
Systems that Produce Warm Antibodies = Kell, Kidd, Duffy, Lutheran 2. Kpa and Kpb
o Kpa = Low Prevalence Antigen (2% of W
Kell Blood Group System (ISBT 006)
Reduced Amount of Kell Glycoprotein in RB
- Consists of 32 High Prevalence and Low Prevalence Antigens
o Kpb = High Prevalence Antigen (99.9% of Po
- 1st Blood Group to be Discovered after Introduction of AHG Testing
o Kpc = Very Rare
- Identified in the serum of Mrs. Kelleher
- All Kell Antigens can ONLY BE FOUND IN RBCs o Named as Kp since first found in Mrs. Penney
- Encoded on Chromosome 7 3. Jsa and Jsb
o KEL Gene = 19 Coding Exons o Jsa = Low Prevalence Antigen (20% of Black
o Mutations in Kell Gene = K0 or Kell Null o Jsb = High Prevalence Antigen
o Named as Js since first found in Mr. John Sutt
Antigens:
4. Kx Antigen (ISBT 019)
1. K and k
o Encoded on X Chromosome (Chrom
o Antithetical Antigens
Chromosome)
o K = Kell = Low Prevalence Antigen (Less than 9% of Population)
o XK1 Gene
o k = Cellano = High Prevalence Antigen (More than 90% of
o Not Part of the Kell Blood Group System but
Population)
Kell Antigens
o Well developed at birth:
o Found in RBCs and Other Tissues such
K = 10 Weeks of Gestation
Organs, Heart and Skeletal Muscle
k = 7 Weeks of Gestation
o Present in All Individuals
o K Antigen is VERY IMMUNOGENIC and is SECOND ONLY TO D
o Kell Antigen Expression depends upon
ANTIGEN in stimulating antibody production.
Antigen
o Absence of Kx Antigen = McLeod Phenotyp
, ***If Kell Antigens are not present, there is no cloud to cov
their detection easier and appear increased in number.
Biochemistry of Kell Antigens and Kx Antigens:
Kell Glycoproteins Anti-K
- RBC Membrane Glycoproteins where Kell Antigens are attached - IgG that reacts well at AHG Phase and may also re
- Member of the Neprilysin (M13) Family of Zinc Endopeptidases Phase
- Produced via Exposure through Pregnancy and Tran
Kell Antigens (K/k, Kpa/Kpb and Jsa/Jsb)
- Anti-K is the 3rd Most Common Antibody Seen in B
- Have 15 Cysteine Amino Acids which forms Disulfide Bonds
o 1st is ABO Antibodies
o Makes them Resistant to Enzymes but Very Sensitive to Sulfhydryl
o 2nd is Rh Antibodies
Reagents
- IgM Anti-K = Very Rare = Associated w/ Bacter
- Examples of Sulfhydryl Reagents = 2-Mercaptoethanol, Dithriothreitol, 2-
0125:B15) which was said to have a Somatic K-Like
Aminoethylisothiouronium Bromide (2-AET) and ZZAP
o It is interesting to note that the IgM Anti-K dis
Kx Antigen of the patient.
- Spans the RBC Membrane 10x and is an RBC Transport Protein - Most Reliable Method of Detecting Anti-K = INDIR
- Kx Antigen is linked to Kell Glycoprotein via a Single Disulfide Bond = TEST
Forms Km Antigen - Polyethylene Glycol = Increases Reactivity of Anti
- Resistant to Sulfhydryl Reagents - RBC Destruction is usually Extravascular via Splenic
***The Kx Antigen is always present on RBC Membranes but sometimes cannot be - Causes Severe HTR and Severe HDFN w/ Fetal Ane
detected or are only in small amounts because the Disulfide Bonds of Kell Anti-Kpa and Anti-Jsa
Antigens form a cloud which masks detection of the Kx Antigen and appear - Rare since they are antibodies to Low Prevalence Ant
decreased in number. - Most Often Detected through Unexpected Incompa
Cases of HDFN
