• The HNA-3a/b polymorphism underlies the genetic basis of the Csa/Csb red cell antigens.

  • Anti-Csa and anti-HNA-3a recognize different epitopes on the SLC44A2 protein.

Abstract

The Csa blood group antigen was identified >50 years ago, but its genetic basis has yet to be elucidated. All our recent genomic investigation has failed to resolve the genetic basis of this enigmatic antigen. By investigating the association of the human neutrophil antigen (HNA)-3a/b polymorphism (rs2288904-G/A) in SLC44A2 with clinical features of sickle cell disease, we incidentally discovered that rare subjects with the homozygous HNA-3b/b genotype also carry the uncommon Cs(a–) phenotype. We genotyped this single-nucleotide polymorphism in a cohort of 25 Cs(a–) subjects and found that all of them showed an HNA-3b/b genotype. This result suggests that the high-prevalence allele with rs2288904 (HNA-3a; 455G) encoding Arg152 encodes the high-prevalence Csa. Accordingly, anti-Csa does not react with solute carrier (SLC)44A2null red blood cells (RBCs), SLC44A2 knockout K562 cells, and K562 cells expressing HNA-3b, confirming that the Csa and Csb antigens are carried on this protein. Furthermore, mass spectrometry analysis of SLC44A2 from neutrophils and RBCs, along with serological investigation, showed that, despite HNA-3a and Csa having the same genetic basis, anti–HNA-3a and anti-Csa recognize different epitopes on the SLC44A2 protein. Overall, our data resolve the genetic bases of the Cs(a–) and Cs(b–) blood phenotypes, with new insights on the anti–HNA-3a specificity.

1.
Koehl
B
,
Vrignaud
C
,
Mikdar
M
, et al
.
Lack of the human choline transporter-like protein SLC44A2 causes hearing impairment and a rare red blood phenotype
.
EMBO Mol Med
.
2023
;
15
(
3
):
e16320
.
2.
Greinacher
A
,
Wesche
J
,
Hammer
E
, et al
.
Characterization of the human neutrophil alloantigen-3a
.
Nat Med
.
2010
;
16
(
1
):
45
-
48
.
3.
Germain
M
,
Chasman
DI
,
de Haan
H
, et al
.
Meta-analysis of 65,734 individuals identifies TSPAN15 and SLC44A2 as two susceptibility loci for venous thromboembolism
.
Am J Hum Genet
.
2015
;
96
(
4
):
532
-
542
.
4.
Constantinescu-Bercu
A
,
Grassi
L
,
Frontini
M
,
Salles-Crawley
II
,
Woollard
K
,
Crawley
JT
.
Activated alpha(IIb)beta(3) on platelets mediates flow-dependent NETosis via SLC44A2
.
Elife
.
2020
;
9
:
e53353
.
5.
Zirka
G
,
Robert
P
,
Tilburg
J
, et al
.
Impaired adhesion of neutrophils expressing Slc44a2/HNA-3b to VWF protects against NETosis under venous shear rates
.
Blood
.
2021
;
137
(
16
):
2256
-
2266
.
6.
Giles
CM
,
Huth
MC
,
Wilson
TE
,
Lewis
HB
,
Grove
GE
.
Three examples of a new antibody, anti-Csa, which reacts with 98% of red cell samples
.
Vox Sang
.
1965
;
10
(
4
):
405
-
415
.
7.
Sererat
T
,
Alexander
J
,
Beatty
J
.
A case report: clinically benign anti-Cs(a)
.
Immunohematology
.
1990
;
6
(
3
):
71
-
72
.
8.
Rolih
SD
.
High-titer, low-avidity (HTLA) antibodies and antigens: a review
.
Transfus Med Rev
.
1989
;
3
(
2
):
128
-
139
.
9.
Zhi
L
,
Feng
W
,
Liang
J
, et al
.
The effect of common variants in SLC44A2 on the contribution to the risk of deep cein thrombosis after orthopedic surgery
.
J Atheroscler Thromb
.
2021
;
28
(
3
):
293
-
303
.
10.
Nair
TS
,
Kommareddi
PK
,
Galano
MM
, et al
.
SLC44A2 single nucleotide polymorphisms, isoforms, and expression: association with severity of Meniere's disease?
.
Genomics
.
2016
;
108
(
5-6
):
201
-
208
.
11.
Shet
AS
,
Lizarralde-Iragorri
MA
,
Naik
RP
.
The molecular basis for the prothrombotic state in sickle cell disease
.
Haematologica
.
2020
;
105
(
10
):
2368
-
2379
.
12.
Li
H
,
Dawood
M
,
Khayat
MM
, et al
.
Exome variant discrepancies due to reference-genome differences
.
Am J Hum Genet
.
2021
;
108
(
7
):
1239
-
1250
.
13.
International Society of Blood Transfusion. Red cell immunogenetics and blood group terminology
. Accessed 17 October 2024. https://www.isbtweb.org/isbt-working-parties/rcibgt.html.
14.
Storch
EK
,
Hillyer
CD
,
Shaz
BH
.
Spotlight on pathogenesis of TRALI: HNA-3a (CTL2) antibodies
.
Blood
.
2014
;
124
(
12
):
1868
-
1872
.
15.
Nair
TS
,
Kozma
KE
,
Hoefling
NL
, et al
.
Identification and characterization of choline transporter-like protein 2, an inner ear glycoprotein of 68 and 72 kDa that is the target of antibody-induced hearing loss
.
J Neurosci
.
2004
;
24
(
7
):
1772
-
1779
.
16.
Curtis
BR
,
Cox
NJ
,
Sullivan
MJ
, et al
.
The neutrophil alloantigen HNA-3a (5b) is located on choline transporter-like protein 2 and appears to be encoded by an R>Q154 amino acid substitution
.
Blood
.
2010
;
115
(
10
):
2073
-
2076
.
17.
Bougie
DW
,
Peterson
JA
,
Kanack
AJ
,
Curtis
BR
,
Aster
RH
.
Transfusion-related acute lung injury-associated HNA-3a antibodies recognize complex determinants on choline transporter-like protein 2
.
Transfusion
.
2014
;
54
(
12
):
3208
-
3215
.
18.
Bayat
B
,
Tjahjono
Y
,
Sydykov
A
, et al
.
Anti-human neutrophil antigen-3a induced transfusion-related acute lung injury in mice by direct disturbance of lung endothelial cells
.
Arterioscler Thromb Vasc Biol
.
2013
;
33
(
11
):
2538
-
2548
.
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