Hong-Gui Xu

Panel reactive antibody in thalassemic serum inhibits proliferation and differentiation of cord blood CD34+ cells in vitro.

Thalassemic children are at a high risk of graft rejection in cord blood transplantation. To investigate this possible mechanism, the authors evaluated the effect of panel reactive antibody on the growth of CD34+ cells in vitro. On semisolid medium, CD34+ cells derived from cord blood were incubated with thalassemic serum, and colony-forming units were counted after 10 days of culture. After incubation with serum-specific panel reactive antibody, profound decreases were found in the numbers of CFU-GM, CFU-GEMM and BFU-E compared with controls. The results indicated that serum-specific panel reactive antibody might have an apparent inhibition effect on proliferation and differentiation of cord blood CD34+ cells.

HMGB1 translocation is involved in the transformation of autophagy complexes and promotes chemoresistance in leukaemia.

Acute lymphoblastic leukaemia (ALL) is a common paediatric cancer and is among the most curable cancers. However, the acquisition of drug resistance is a significant obstacle to the achievement of favourable outcomes, and autophagy is regarded as a mechanism that underlies chemoresistance. In this study, RT-qPCR was used to measure the expression of HMGB1 and Beclin1 in bone marrow mononuclear cells. A CCK-8 test was conducted to assess cell viability. Western blot, immunofluorescence and transmission electron microscopic analyses were performed to evaluate the autophagy levels. Immunoprecipitation analysis was performed to detect protein-protein interactions in the autophagy complexes. We found that HMGB1 expression correlated with the clinical status of ALL. In vitro, anticancer agent-induced cytotoxic effects were associated with autophagy-related drug resistance, and these effects were ameliorated by FIP200 depletion or the application of autophagy inhibitors. Moreover, the Ulk1‑Atg13-FIP200 complex, which promotes HMGB1 trafficking, acted upstream of the HMGB1-Beclin1 and PI3KC3-Beclin1 complexes and played a critical role in autophagy. Targeting the transformation of autophagic complexes or HMGB1 translocation may suppress autophagy and consequently overcome chemoresistance in leukaemia.

Homing and engraftment of bone marrow cells derived from different donors in a murine model of sensitization

Abstract Sensitized recipients are at a high risk of graft rejection in hematopoietic stem cell transplantation. To explore the trace of donor cells, we tried to explore homing and engraftment of bone marrow cells (BMCs) derived from different donors in a murine model of sensitization. Sensitized BALB/c mice were used as transplanted recipients, which received BMCs derived from C57BL/6 or BALB/c donors after lethal irradiation. The homing study showed that the donor cells decreased along with time in recipients of the C57BL/6 donor group, but the donor cells increased along with time in recipients of the BALB/c donor group. For the engraftment assay, all the sensitized recipients transplanted with BMCs derived from C57BL/6 donors died after lethal irradiation. In contrast, all the recipients transplanted with BMCs derived from BALB/c donors got long-term survival. Our results suggest that it is crucial to have human leukocyte antigen identical donors for sensitized recipients during hematopoietic stem cell transplantation.

Evaluation of hepatic iron overload in Chinese children with β-thalassemia major.

Patients with β-thalassemia major require long-term blood transfusions, resulting in hepatic iron overload. Thirty-five Chinese children with β-thalassemia major were recruited in the present studies. Hepatic iron overload was evaluated by histological grading. The relationships between hepatic iron overload and both serum biochemical markers and magnetic resonance imaging (MRI) examination were studied. The majority of the patients showed high degrees of hepatic iron overload by histological study. The degree of hepatic iron overload was correlated with serum ferritin (r = .70, P < .01), hyaluronic acid (r = .58, P = .011), and type III precollagen (r = .55, P = .035). Moreover, hepatic iron overload showed a negative correlation with liver to muscle signal intensity ratio (r = −.44, P = .012), and a positive correlation with red marrow area percentage (r = .52, P < .01). These results indicated that hepatic iron overload might be assessed by serum biochemical markers and MRI examination.

Modified conditioning regimen improves outcomes of unrelated donor peripheral blood stem cell transplantation for β-thalassaemia major patients

The objective of this study was to evaluate the feasibility of a modified conditioning regimen for the treatment of patients with β‐thalassaemia major (TM), using unrelated donor peripheral blood stem cell transplantation (UD‐PBSCT).

A pilot study on detection of PRA in the children with severe -thalassemia using enzyme-linked immunosorbent assay in China.

Aims: To investigate the distribution of food allergens in pediatric allergic rhinitis. Methods: 106 children diagnosed with allergic rhinitis were reviewed and divided into two age groups, including preschooler (2-5 years old) group, 48 cases; and school children group (6-13 years), 58 cases. Allergen-specific IgE for the food allergens and inhalant allergens in patient’s serum was determined using the AllergyScreen system (Mediwiss Analytic GmbH, Germany). Results: Out of 106 AR children, 88 (83.02%) were tested positive for food allergen-specific serum IgE (sIgG), 97 (91.51%) positive for inhalant allergen-specific sIgE. Among these children, 79 (74.53%) were positive for both food and inhalant allergens, 9 (8.49%) were positive only for food allergens, and 18 (16.98%) were negative for food allergens but positive for inhalant allergens. Out of 88 children positive for food allergens, 34 (32.08%) were positive for single food allergen, 54 (50.94%) were positive for multiple food allergens. The top 6 food allergens, in the order of their positivity rates, were milk (52.83%), eggs (30.19%), beef (26.42%), cashew (26.42%), lamb (12.26%) and crabs (10.38%). The food allergen-positive rate in the preschooler group was higher than that in the school children group (P<0.05). Conclusion: Majority of the children with allergic rhinitis are also positive for food allergens, suggesting that food allergens might be one of the main causes for pediatric allergic rhinitis.The present study was undertaken to ascertain the affinity of the amino acid D-Tryptophan (D-Trp) towards the particular receptors on the melanophores of a major carp Labeo rohita (Ham.). D-Trp, which is sweet in taste, in the dose range of 4.9 x 10 -16 M to 4.9 x 10 -4 M has induced a dose-dependent aggregation (MSI 3.72 ± 0.15 to 1.09 ± 0.02) in the isolated scale melanophores of the dorso-lateral region of this fish. The precise binding of the ligand D-Trp with its receptors is partially dependent, in eliciting its actions, on the release of neurotransmitters. The melanophores do not get desensitized under 90 min incubation within the agonist D-Trp. The general α adrenoceptors as well as the α 2 adrenoceptors are involved in the tastant (D-Trp) induced aggregation of the melanophores. D-Trp demonstrates that its aggregatory effects are mediated with the intervention of the β adrenoceptors. Inhibition of the D-Trp induced aggregatory effect has also been observed when the melanophores were pretreated with the antibiotic neomycin. The aggregating nature of D-Trp suggests that it could be binding with the receptors of aggregation causing ligands.

Clinical study on cytomegalovirus-associated haemophagocytic syndrome following allogeneic hemotoic stem cell transplantation

Aims: To investigate the distribution of food allergens in pediatric allergic rhinitis. Methods: 106 children diagnosed with allergic rhinitis were reviewed and divided into two age groups, including preschooler (2-5 years old) group, 48 cases; and school children group (6-13 years), 58 cases. Allergen-specific IgE for the food allergens and inhalant allergens in patient’s serum was determined using the AllergyScreen system (Mediwiss Analytic GmbH, Germany). Results: Out of 106 AR children, 88 (83.02%) were tested positive for food allergen-specific serum IgE (sIgG), 97 (91.51%) positive for inhalant allergen-specific sIgE. Among these children, 79 (74.53%) were positive for both food and inhalant allergens, 9 (8.49%) were positive only for food allergens, and 18 (16.98%) were negative for food allergens but positive for inhalant allergens. Out of 88 children positive for food allergens, 34 (32.08%) were positive for single food allergen, 54 (50.94%) were positive for multiple food allergens. The top 6 food allergens, in the order of their positivity rates, were milk (52.83%), eggs (30.19%), beef (26.42%), cashew (26.42%), lamb (12.26%) and crabs (10.38%). The food allergen-positive rate in the preschooler group was higher than that in the school children group (P<0.05). Conclusion: Majority of the children with allergic rhinitis are also positive for food allergens, suggesting that food allergens might be one of the main causes for pediatric allergic rhinitis.The present study was undertaken to ascertain the affinity of the amino acid D-Tryptophan (D-Trp) towards the particular receptors on the melanophores of a major carp Labeo rohita (Ham.). D-Trp, which is sweet in taste, in the dose range of 4.9 x 10 -16 M to 4.9 x 10 -4 M has induced a dose-dependent aggregation (MSI 3.72 ± 0.15 to 1.09 ± 0.02) in the isolated scale melanophores of the dorso-lateral region of this fish. The precise binding of the ligand D-Trp with its receptors is partially dependent, in eliciting its actions, on the release of neurotransmitters. The melanophores do not get desensitized under 90 min incubation within the agonist D-Trp. The general α adrenoceptors as well as the α 2 adrenoceptors are involved in the tastant (D-Trp) induced aggregation of the melanophores. D-Trp demonstrates that its aggregatory effects are mediated with the intervention of the β adrenoceptors. Inhibition of the D-Trp induced aggregatory effect has also been observed when the melanophores were pretreated with the antibiotic neomycin. The aggregating nature of D-Trp suggests that it could be binding with the receptors of aggregation causing ligands.