Page 1920 - Hematology_ Basic Principles and Practice ( PDFDrive )

1700 Part XI Transfusion Medicine

C4d, remains on the RBC. This C4d glycoprotein carries the Ch/ defined by an amino acid polymorphism on SLC29A1 (p.Glu391Lys),
Rg blood group antigens. The antigens are stable in stored serum or while the At(a−) members of a rare family affected by bone malforma-
plasma, and the phenotypes of this system are most accurately defined tion lacked the protein due to an inactivating mutation in the
in plasma by agglutination inhibition tests. SLC29A1 gene: c.589+1G>C. The antigen defined by the antibody
produced by the null phenotype was named AUG1, and the antigen
a
Antibodies Antibodies in the Ch/Rg system are usually IgG, do not defined by the amino acid Glu391 (At ) was named AUG2. 27
activate complement, and are considered benign. Considerable varia-
a
tion may be common in the reaction strength obtained with different Antibodies. Anti-At are mostly IgG although may contain IgM.
a
RBC samples. Although these antibodies do not generally cause While HDFN due to anti-At is rare, the antibodies can cause severe
DHTR, they have caused anaphylactic reactions. The antibodies have hemolytic transfusion reactions.
not caused HDFN.
JR Blood Group System REFERENCES
a
The Jr antigen is carried on ABCG2, a member of the ATP-binding
cassette family of multipass membrane proteins. The protein is 1. Reid ME, Lomas-Francis C, Olsson ML: Blood group antigen facts book,
broadly distributed and is a high-affinity urate transporter. It is also ed 3, San Diego, 2012, Academic Press.
involved in porphyrin transport and in multidrug resistance in some 2. Daniels G: Human blood groups, ed 3, Oxford, 2013, Wiley-Blackwell.
cancers. The Jr(a−) phenotype is the null phenotype and Jr(a−) 2a. Association Bulletin #16-02: Mitigating the anti-CD38 interference
individuals lack the protein. Many different mutations have been with serologic testing, 2016, AABB. <https://www.aabb.org/programs/
identified for this phenotype although it is more common among the publications/bulletins/Documents/ab16->.
Japanese (where it is associated with gout) and the Roma population 3. Heddle NM, Soutar RL, O’Hoski PL, et al: A prospective study to
in Europe. determine the frequency and clinical significance of alloimmunization
post-transfusion. Br J Haematol 91:1000, 1995.
a
Antibodies Anti-Jr are usually IgG, do not activate complement 4. Rosse WF, Gallagher D, Kinney TR, et al: Transfusion and alloimmuni-
and do not generally cause DHTR or HDFN, however two cases of zation in sickle cell disease. Blood 76:1431, 1990.
severe HDFN have been reported. 5. Aygun B, Padmanabhan S, Paley C, et al: Clinical significance of RBC
alloantibodies and autoantibodies in sickle cell patients who received
Lan Blood Group System transfusions. Transfusion 42:37, 2002.
Lan too, is carried by an ATP-binding cassette protein, in this case 6. Vichinsky EP, Earles A, Johnson RA, et al: Alloimmunization in sickle
ABCB6, a protein that is widely expressed. It is highly expressed in cell anemia and transfusion of racially unmatched blood. N Engl J Med
fetal liver and upregulated during erythropoiesis. ABCB6 is important 322:1617, 1990.
in heme synthesis and transports heme and porphyrins into the 7. Cox JV, Steane E, Cunningham G, et al: Risk of alloimmunization
mitochondria. The Lan− phenotype is the null phenotype and it and delayed hemolytic transfusion reactions in patients with sickle cell
arises from many different molecular backgrounds but is not associ- disease. Arch Intern Med 148:2485, 1988.
ated with a disease phenotype. Lan antigen expression is variable on 8. Chou ST, Jackson T, Vege S, et al: High prevalence of red blood cell allo-
erythrocytes. immunization in sickle cell disease despite transfusion from Rh-matched
minority donors. Blood 122:1062, 2013.
Antibodies Anti-Lan are generally IgG and do not bind complement 9. Chou ST, Westhoff CM: The role of molecular immunohematology in
but have caused mild to severe DHTR and mild HDFN. sickle cell disease. Transfus Apher Sci 44:73, 2011.
10. Yazdanbakhsh K, Ware RE, Noizat-Pirenne F: Red blood cell alloim-
Vel Blood Group System munization in sickle cell disease: pathophysiology, risk factors, and
The Vel blood group antigen is dependent on the SMIM1 protein transfusion management. Blood 120:528, 2012.
for expression and a 17-bp mutation in the SMIM1 gene accounts 11. Matteocci A, Pierelli L: Red blood cell alloimmunization in sickle cell
for the vast majority of Vel− individuals and absence of SMIM1. The disease and in thalassaemia: current status, future perspectives and
protein is widely expressed but more highly expressed on erythrocytes, potential role of molecular typing. Vox Sang 106:197, 2014.
salivary glands, and testes, although its function is unknown. Vel 12. Osby M, Shulman IA: Phenotype matching of donor red blood cell units
antigen expression is variable on RBCs. for nonalloimmunized sickle cell disease patients: a survey of 1182 North
American laboratories. Arch Path Lab Med 129:190, 2005.
Antibodies Anti-Vel are often a mixture of IgM and IgG and readily 13. Bruce LJ, Guizouarn H, Burton NM, et al: The monovalent cation
bind complement. While HDFN caused by anti-Vel is rare, the leak in overhydrated stomatocytic red blood cells results from amino
antibodies can cause severe hemolytic transfusion reactions. acid substitutions in the Rh-associated glycoprotein. Blood 113:1350,
2009.
CD59 Blood Group System 14. Fung MK, Grossman BJ, Westhoff CM, et al, editors: Technical manual,
An antibody in the plasma of a young patient with CD59 deficiency ed 18, Bethesda, Md, 2014, American Association of Blood Banks.
qualified CD59 as a blood group antigen. CD59 is a GPI-linked 14a. Schwarz HP, Dorner F: Karl Landsteiner and his major contributions
protein on the erythrocyte and is important in complement regula- to haematology. Br J Haematol 121:556–565, 2003.
tion. It inhibits the formation of the membrane attack complex 15. Clausen H, Hakomori S: ABH and related histo-blood group antigens;
(MAC) by specifically binding to C8 and C9. Like other GPI-linked immunochemical differences in carrier isotypes and their distribution.
proteins, it is absent from the erythrocytes of PNH patients and its Vox Sang 56:1, 1989.
absence is the underlying cause of hemolysis. 16. Oriol R, Candelier JJ, Mollicone R: Molecular genetics of H. Vox Sang
78:105, 2000.
Antibodies Only one example of the antibody has been reported. It 17. Storry JR, Olsson ML: The ABO blood group system revisited: A review
was clinically benign although a positive DAT was observed following and update. Immunohematology 25:48, 2009.
one of the transfusions. 18. Rydberg L: ABO-incompatibility in solid organ transplantation. Transfus
Med 11:325, 2001.
Augustine Blood Group System 19. Curtis BR, Edwards JT, Hessner MJ, et al: Blood group A and B antigens
The blood group system Augustine (symbol AUG; number 036) was are strongly expressed on platelets of some individuals. Blood 96:1574,
recently assigned to the equilibrative nucleoside transporter 1 protein 2000.
(SLC29A1; ENT1) after it was identified as the carrier of the At a 20. Cooling LL, Kelly K, Barton J, et al: Determinants of ABH expression
antigen. The At(a−) phenotype in individuals of African origin is on human blood platelets. Blood 105:3356, 2005.