UNCOMMON BLOOD GROUPS P2 Flashcards
(68 cards)
Named after the first two antibody producers, Ch for Chido and Rg for Rodgers.
These two antibodies were described in 1967 and 1976.
The Chido/Rodgers (017) System
Serologically, they were both (The Chido/Rodgers (017) System) characterized as _______ because antigen strength on different samples of RBCs was variable.
NEBULOUS
It was also appreciated that both anti-Ch and anti-Rg could be neutralized by
_______
plasma
Ch and Rg antigens are not ______ to the RBC membrane.
Rather, they are on the _____ component of complement (C4), and are adsorbed onto RBCs from plasma
intrinsic ; fourth
C4 glycoprotein has two isoforms:
- C4B carries the Ch antigens
- C4A expresses Rg antigens.
The genes C4A and C4B at two closely linked loci located on chromosome __ at position 6p21.3 encode these isoforms.
6
The Chido/Rodgers system consists of nine antigens: ___ to ___, ____ and ___ are all high prevalence; ___ has a prevalence of about 15%.
Ch1 to Ch6, Rg1, and Rg2 ; WH
___ is present in 96% to 98% of most populations.
___ is present in 97% to 98% of most populations.
The antigens are destroyed by ficin and papain but are resistant to treatment with DTT and glycine-acid EDTA.
Ch; Rg
Anti-Ch and anti-Rg are usually ___ and react weakly, often to moderate or high titration endpoints.
IgG
Neutralization of anti-Ch and anti-Rg with pooled plasma is often used as part of the identification of these antibodies in a patient’s serum. ____ and ______ are clinically insignificant for transfusion.
Anti-Ch and anti-Rg
Was named in 1960 after Mrs. Gerbich, the first antibody producer.
The Gerbich (020) System
There are currently six high-prevalence Gerbich antigens (…….) and five low-prevalence antigens (…….)
Ge2, Ge3, Ge4, GEPL, GEAT, and GETI
Wb, Lsa, Ana, Dha and GEIS
- The antigen are carried on sialoglycoprotein structures GPC and GPD.
- There are about ______ copies of GPC, and ______ copies of GPD per RBC.
Gerbich Antigen ; 135,000 ; 50,000
- _____ and ____ = encoded by the GYPC gene, located on chromosome 2
at position 2q14.3. - ______ = Gerbich null phenotype
- All were English or North American.
- Ge null Phenotype are elliptocytic
GPC and GPD ; Leach type
Gerbich Negative Phenotypes:
Ge: -2, 3, 4
Type: Yus
Antibody: Anti-Ge2
Gerbich Negative Phenotypes:
Ge: -2, -3, 4
Type: Gerbich
Antibody: Anti-Ge2 or anti-Ge3
Gerbich Negative Phenotypes:
Ge: -2, -3, -4
Type: Leach Type
Antibody: Anti-Ge2 or anti-Ge3
___ phenotype has been found in Mexicans, Israelis, Mediterraneans.
Yus
The Gerbich phenotype is _______ in certain areas of Papua, New
Guinea, and has also been found among Europeans, Africans, Native
Americans, Japanese, and Polynesians.
- Expressed at birth.
- Are resistant to treatment with _____ and _______;
- ____ and ____ are ficin and papain sensitive,
- but ____ is ficin resistant.
polymorphic ; DTT and glycine-acid EDTA ; Ge2 and Ge4 ; Ge3
Gerbich Antibodies
- May be IgM, but most are ___.
- are sometimes clinically significant for transfusion and sometimes not.
- can be eluted from DAT+ cord bloods, but only 3 cases of serious HDFN due to anti-Ge3, and two were children of the same mother.
- babies born to mothers with anti-Ge3 should be monitored for several weeks after birth for anemia.
- _______ most common of the Gerbich antibodies. The antibody made by the Ge:-2,3,4 phenotype individuals
- but it is also more common antibody made by the Ge:-2,-3,4 phenotype and Ge:-2,-3,-4 phenotype individuals.
- ____ is less frequently made by the Ge;-2,-3,4 and Ge:-2,-3,-4
- ______ is a very rare antibody.
IgG ; Anti-Ge2 ; Anti-Ge3 ; Anti-Ge4
In 1965, an antibody was found in a black prenatal patient, Mrs. Cromer, that reacted with all RBCs except her own and two siblings.
- originally thought her antibody recognized an antigen antithetical to ____ of the Rh blood group system.
- the antibody was named ____ in 1975.
The Cromer (021) System ; Goa ; anti-Cra
- The antigens of the Cromer system are carried on __________ (DAF, CD55), a complement-regulator protein.
- The gene ____ is located on chromosome 1 at position 1q32.
- The glycoprotein encoded by the gene is attached to the RBC
membrane through a GPI linkage. - _______ are deficient in DAF so they also lack Cromer antigens.
- The Cromer system has ___ antigens.
- ___ have been classified as high-prevalence antigens and ___ low-prevalence antigens.
- All these antigens are absent from Inab phenotype RBCs, the Cromer null phenotype, which is very rare.
decayaccelerating factor ;
CD55 ;
PNHIII RBCs;
19 ; 15 ; 3
- ______ appears to be a novel Inab-like phenotype with a mutation that affects the expression of the Cromoer antigens.
- The _____ phenotype is typically found in blacks and is not found in whites.
- Three Cromer antigens, ___, ____, and ____, are antithetical;
- ___ is the high-prevalence.
- ____ (low prevalence) and ___ (high prevalence) are also antithetical.
- The ____antigen is of high prevalence
CROM (CROM19) ;
Cr(a-) ;
Tca, Tcb, and Tcc
Tca ;
WESa ; WESb;
Dra
- _____ RBCs have weakened expression of all other high-prevalence Cromer antigens
due to a markedly reduced copy number of DAF. - The Dr(a-) phenotype has been found only among jews from Bakhara and in Japanese.
- Cromer system antigens are resistant to treatment with ______ and ____ but are destroyed by _______, which is used to distinguish specificities in this from other blood group antibodies.
- Cromer antigens are weakened with ____ treatment and are resistant to ______
Dr(a-) ;
ficin and papain ; a-chymotrypsin
DTT ; glycine-acid EDTA.