Clinical impact of HLA-DR15, a minor population of paroxysmal nocturnal haemoglobinuria-type cells, and an aplastic anaemia-associated autoantibody in children with acquired aplastic anaemia.
Aplastic anaemia (AA) is defined as a pancytopenia caused by bone marrow failure, and its pathogenesis is thought to involve autoimmune processes. Several predictive markers of the response to immunosuppressive therapy (IST) have been proposed, which appear to reflect the immune pathophysiology. We prospectively investigated the presence of human leucocyte antigen (HLA)-DR15, a minor population of paroxysmal nocturnal haemoglobinuria (PNH)-type cells, and antibodies to the recently identified autoantigen postmeiotic segregation increased 1 (PMS1) in 103 children with AA enrolled in a multicentre study. In contrast to adults, children with AA did not show an increased frequency of HLA-DR15. In addition, a sensitive flow cytometric assay revealed that children with AA have a much lower prevalence of PNH-type cells (21.4%) than reported for adults with this disease. An immunoblotting assay detected anti-PMS1 antibody in 15 of 103 (14.6%) of the children. Finally, the response rate to IST was not significantly different between patients with and without DR15 (45.5% vs. 54.0%), PNH-type cells (68.2% vs. 53.1%) or anti-PMS1 antibody (40.0% vs. 59.1%). The current study did not confirm a correlation between these markers and the response to IST, suggesting that there is a difference in the pathophysiologies of adult and paediatric AA.
Department of Paediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Nao
N
Yoshida
Hiroshi
H
Yagasaki
Yoshiyuki
Y
Takahashi
Tomoko
T
Yamamoto
Juan
J
Liang
Yue
Y
Wang
Makito
M
Tanaka
Asahito
A
Hama
Nobuhiro
N
Nishio
Ryoji
R
Kobayashi
Noriko
N
Hotta
Keiko
K
Asami
Atsushi
A
Kikuta
Takashi
T
Fukushima
Naoto
N
Hirano
Seiji
S
Kojima
D000293:Adolescent; D000741:Anemia, Aplastic / Q000276:immunology* / Q000628:therapy; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D015153:Blotting, Western / Q000379:methods; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry; D005787:Gene Frequency; D006684:HLA-DR Antigens / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D059810:HLA-DR Serological Subtypes; D006457:Hemoglobinuria, Paroxysmal / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007165:Immunosuppression Therapy; D007223:Infant; D008297:Male; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
D001323:Autoantibodies; D001324:Autoantigens; D015415:Biomarkers; D006684:HLA-DR Antigens; D059810:HLA-DR Serological Subtypes; C106559:HLA-DR15 antigen; C540698:postmeiotic segregation increased 1 antigen, human