Objective:To explore the clinical characteristics of Diamond-Blackfan anemia (DBA) in children caused by RPL5 gene mutation, thus improving the understanding of the etiology of DBA.Methods:The clinical data and sequencing results of a child with DBA caused by RPL5 gene mutation treated in the Children′s Hospital of Fudan University were analyzed.In addition, through literature review of reported DBA cases at domestic and home, summarized the clinical features of DBA.Results:The patient was an 8-year-old male child.Bone marrow puncture examination of the child showed DBA, and a heterozygous mutation of RPL5 gene c. 657C>G, p.Y219X was identified for the first time in the DBA case.A total of 47 cases of DBA were retrieved from the online databases plus the one reported in this study (48 cases in total), and their clinical features were summarized as follows: the incidence of DBA was similar in men and women.The number of DBA patients in Asia was lower than that in Europe and the United States.DBA was mainly a sporadic disease.Among the exon mutations in European and American cases of DBA, 43.0% of them had mutations in Exon3.The malformation rate of DBA patients with RPL5 mutation was 81.3% (39/48 cases, excluding short stature cases), which was higher than that of patients with other mutation types.The response rate of glucocorticoid therapy for DBA was 46.0%, which was lower than that of the overall response rate.Conclusions:chr1: 93303142(c.657 C>G, p.Y219X) is a newly detected mutation of RPL5 gene in the DBA case, which expands the pathogenic gene spectrum of DBA.Patients with RPL5 mutation have higher rates of teratogenicity and multiple teratogenicity, and a lower response rate to hormone therapy.

OBJECTIVE: To detect pathological variant in two patients with Chediak-Higashi syndrome (CHS) from a consanguineous family and to explore its genotype-phenotype correlation. METHODS: Clinical data was collected for this pedigree. Genomic DNA was prepared from probands' peripheral leukocytes and their relatives' fingernail. Whole exome sequencing and Sanger sequencing were carried out to detect potential variant of the LYST gene. RESULTS: The proband presented with partial oculocutaneous albinism, immunodeficiency and acidophilic inclusion body in bone marrow and blood smears. A novel homozygous nonsense variant c.8782C>T (p.Gln2928*) was identified in exon 34 of the LYST gene in the sib pair. The same variant was found to be in heterozygous status in 6 unaffected individuals from the pedigree. CONCLUSION Above result enriched the mutational spectrum of CHS and provided a basis for genetic counseling and prenatal diagnosis for this pedigree.
Chediak-Higashi Syndrome ; genetics ; Exons ; Heterozygote ; Humans ; Mutation ; Pedigree ; Sequence Analysis, DNA ; Vesicular Transport Proteins ; genetics ; Whole Exome Sequencing

Objective To explore dendritic cells (DCs)-mediated antigen presentation for radiation-injured cells by using the in vitro cell co-culture technology to simulate the in vivo microenvironment of the lung tissue. Methods ⁶⁰Co γ-irradiated mouse lung epithelial cells (MLE-12) were cultured with bone marrow-derived DCs and/or splenic T lymphocytes for 48 hours. Flow cytometry was used to measure the expression levels of costimulatory molecules (CD80/86) and antigenic peptide recognition complexes (the major histocompatibility complex [MHC] class Ⅰ/Ⅱ) on DCs and T cell activation markers (CD69/28/152) as well as the numbers of CD4⁺ and CD8⁺ T cells. Results ⁶⁰Co γ irradiation significantly increased the apoptosis rate of MLE-12 cells in a dose-dependent manner, and significantly stimulated the expression of CD80/86 and MHC Ⅱ on DCs, without direct activation of T cells. After γ (6 Gy)-irradiated MLE-12 cells were co-cultured with DCs and T lymphocytes for 48 h, there were significant increases in the expression of CD69 and CD28 on T cells, the numbers of CD4⁺ and CD8⁺ T cells, and the expression of CD86 and MHC I on DCs, as compared with the control groups. Conclusion Radiation-injured cells can stimulate antigen presentation by DCs and activate T cells.

Objective To investigate the role of complement in radiation-induced lung injury in mice after chest irradiation with ⁶⁰Co γ-rays at a single dose of 20 Gy. Methods C57BL/6 mice underwent chest irradiation with ⁶⁰Co γ-rays at a single dose of 20 Gy, followed by observation for the inflammatory reaction of the lung tissue in the early stage (within 15 d) and pulmonary fibrosis in the later stage (30 and 180 d). Enzyme-linked immunosorbent assay was used to measure the levels of C2, C3a, C4, and C5b-9 in the lung tissues at 1, 3, 7, 15, 30, and 180 d after irradiation. The expression of complement mRNA in BEAS-2B cells after irradiation was determined using RT-PCR. Results Radiation-induced lung injury in micepresented as inflammatory response in the early stage and fibrosis in the late stage. Complement C2, C4, and C5b-9 complexes were increased in the early period (3 or 7 d) after irradiation (P < 0.05), which might be associated with the inflammatory response induced by irradiation. During 3 to 180 d, complement C3a was significantly higher in the irradiated mice than in the control mice, suggesting a close relationship between C3a and radiation-induced lung injury. The irradiated cells showed increased mRNA expression of C2 and C3, with no changes in the mRNA levels of C4 and C5. Conclusion Different complement proteins have varying responses to radiation-induced lung injury, among which C3a is closely related to radiation-induced lung injury, suggesting that regulating C3a and its receptors may be a new way to prevent and treat radiation-induced lung injury.