Screening of aplastic anaemia-related genes in bone marrow CD4^+ T cells by suppressive subtractive hybridization

Background CD4^＋ T cells play a crucial role in the pathogenesis of aplastic anaemia. However, the mechanisms of over-proliferation, activation, infiltration of bone marrow and damage to haematopoietic ceils of CD4^＋ T cells in aplastic anaemia are unclear. Therefore, we screened differentially expressed genes of bone marrow CD4^＋ T cells of aplastic anaemia patients and normal donors by suppressive subtractive hybridization to investigate the pathogenesis of aplastic anaemia. Methods The bone marrow mononuclear cells of a first visit aplastic anaemia patient and a healthy donor of the same age and sex were isolated using lymphocyte separating medium by density gradient centrifugation. With the patients as ＂tester＂ and donor as ＂driver＂, their CD4^＋T cells were separated with magnetic bead sorting and a cDNA library established by suppressive subtractive hybridization. Then 15 of the resulting subtracted cDNA clones were randomly selected for DNA sequencing and homological analysis. With semiquantitative RT-PCR, bone marrow samples from 20 patients with aplastic anaemia and 20 healthy donors assessed the expression levels of differentially expressed genes from SSH library. Results PCR detected 89 clones in the library containing an inserted fragment of 100 bp to 700 bp. Among 15 sequenced clones, 12 were known genes including 3 repeated genes. Compared with normal donors, there were 9/12 genes over-expressed in bone marrow CD4^＋T cells of patients with aplastic anaemia. The effects of these genes included protein synthesis, biology oxidation, signal transduction, proliferative regulation and cell migration. Not all these genes had been reported in the mechanisms of haematopoietic damage mediated by CD4^＋ T cells in aplastic anaemia. Conclusions Screening and cloning genes, which regulate functions of CD4^＋ T cells, are helpful in elucidating the mechanisms of over proliferation, activation, infiltrating bone marrow and damaging haematopoietic cells of CD4^＋ T cells in aplasUc anaemia.

Hepatitis- associated aplastic anaemia:clinical characteristics and immunosuppressive therapy outcomes

Objective To analyze the clinical characteristics and to evaluate immunosuppressive therapy(IST)response and survival in hepatitis-associated aplastic anemia(HAAA).Methods We retrospectively analyzed clinical characteristics,IST response,long-term survival and clonal evolution in 41 HAAA patients,and

From Surgery to Hematology: Fanconi Anemia about a Case of a Senegalese Child

Fanconi anaemia (FA) is a rare genetic abnormality. Most of FA reported from the sub-Saharan population came from southern Africa, with many patients linked to a mutation in the FANC G gene. Classic triads of this disorder are: a varied malformation, bone marrow failure, and short stature. This disorder is also associated with predisposition to malignancies. These multiple manifestations, sometimes not uniform, often cause diagnostic delay. We here report a 13-year-old Senegalese boy with FA. He was followed up for polydactyly-repair surgery. Importantly, pre-operative blood check-up revealed severe anaemia, which prompted us to perform bone marrow aspiration: examination revealed dysmyelopoiesis. Being triggered by this, systematic examinations were performed, which revealed other signs indicative of FA;i.e., radial spine abnormalities, triangular face, etc. The diagnosis of FA was strongly suggested, which prompted genetic examination. The chromosomal breakage test detected cellular hypersensitivity to DNA, which confirmed the diagnosis. He is receiving transfusion support, and androgens use is being considered. This case highlights the importance of preoperative examination. Physicians must be aware that FA, although its incidence is low, can be hidden behind infantile anaemia.