Change in serum IgG antibody during the recovery stage of Omicron variant infection in children: an analysis of 110 cases / 中国当代儿科杂志

OBJECTIVES@#To investigate the serum level of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific RBD IgG antibody (SARS-CoV-2 IgG antibody for short) in children with SARS-CoV-2 Omicron variant infection during the recovery stage, as well as the protective effect of SARS-CoV-2 vaccination against Omicron infection.@*METHODS@#A retrospective analysis was performed on 110 children who were diagnosed with coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 Omicron variant infection in Tianjin of China from January 8 to February 7, 2022. According to the status of vaccination before diagnosis, they were divided into a booster vaccination (3 doses) group with 2 children, a complete vaccination (2 doses) group with 90 children, an incomplete vaccination (1 dose) group with 5 children, and a non-vaccination group with 13 children. The clinical data and IgG level were compared among the 4 groups.@*RESULTS@#The complete vaccination group had a significantly higher age than the non-vaccination group at diagnosis (P<0.05), and there was a significant difference in the route of transmission between the two groups (P<0.05). There were no significant differences among the four groups in sex, clinical classification, and re-positive rate of SARS-CoV-2 nucleic acid detection (P>0.05). All 97 children were vaccinated with inactivated vaccine, among whom 85 children (88%) were vaccinated with BBIBP-CorV Sinopharm vaccine (Beijing Institute of Biological Products, Beijing, China). At 1 month after diagnosis, the booster vaccination group and the complete vaccination group had a significantly higher level of SARS-CoV-2 IgG antibody than the non-vaccination group (P<0.05), and at 2 months after diagnosis, the complete vaccination group had a significantly higher level of SARS-CoV-2 IgG antibody than the non-vaccination group (P<0.05). For the complete vaccination group, the level of SARS-CoV-2 IgG antibody at 2 months after diagnosis was significantly lower than that at 1 month after diagnosis (P<0.05).@*CONCLUSIONS@#Vaccination with inactivated SARS-CoV-2 vaccine has a protective effect against Omicron infection in children. For children vaccinated with 2 doses of the vaccine who experience Omicron infection, there may be a slight reduction in the level of SARS-CoV-2 IgG antibody at 2 months after diagnosis. Citation:Chinese Journal of Contemporary Pediatrics, 2022, 24(7): 736-741.

The Effects of Decitabine Combined with All-Trans Retinoic Acid on the Number of Immune Cells in Myeloid Neoplasms / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of decitabine (DEC) combined with all-trans retinoic acid (ATRA) on the number of immune cells, efficacy and adverse reactions in the treatment of myeloid neoplasms patients.@*METHODS@#Eighty-four patients with myeloid tumors, including AML, MDS-EB-1 or MDS-EB-2 treated by the regimen containing decitabine in our hospital from January 2009 to October 2019 were enrolled and retrospectively analyzed, among the patients, 21 patients treated with DEC alone, 24 patients treated with DEC combined with ATRA (DEC/ATRA) and 39 patients treated with DEC combined with G-CSF priming regimen (DEC/priming). The changes of peripheral blood immune cell levels before and after treatment of the patients between the three groups were compared, and the differences in clinical efficacy and adverse reactions of the patients between the three groups were also compared.@*RESULTS@#There was no statistical differences in the number of immune cells among the patients in the three groups before treatment (P>0.05). NK cell levels decreased significantly in the patients in DEC and DEC/ATRA group after treatment (P<0.05); After treatment, the levels of CD8+ and CD3+T cells in the patients treated by DEC /priming regimen significantly increased (P<0.05), while the levels of CD3-HLA-DR+ B cells significantly decreased (P<0.05). The overall response rate (ORR) of the patients in DEC/ATRA group (75%) and DEC/priming group (74.36%) was significantly higher than 42.86% in DEC monotherapy group, and the differences showed statistically significant (P<0.05), while the ORR between the patients in DEC/ATRA and DEC/priming group showed no statistic differences (P>0.05). There were no statistical differences in overall survival (OS) and incidence of bleeding between the patients in the three groups (P>0.05). The incidences of grade 3 to 4 bone marrow suppression and the infection rate of the patients in DEC monotherapy and DEC/ATRA group were significantly lower than that in DEC/priming regimen group after treatment (all P<0.05), however, there was no statistical difference between DEC monotherapy and the DEC/ATRA group.@*CONCLUSION@#The efficacy of DEC/ATRA on myeloid neoplasms is comparable to that of DEC/priming regimen, and the anti-myeloid tumor effect of DEC/ATRA regimen may be related to the regulation of NK cells and T cells.

Research progress on human acute leukemia xenograft mouse models / 中国实验血液学杂志

The methods for modeling human acute leukemia in mice include xenotransplantation of human leukemia cells, retroviral transduction/transplantation, transgenesis, chemical mutagenesis and insertional mutagenesis. Establishing human acute leukemia mouse models through xenograft is an important way to study acute leukemia. This review focuses on the newest progress of studies on human acute leukemia xenograft mouse models in the regards of the immunodeficiency mouse, preconditioning, cytokines, cell transplantation, the evaluation and application of model.