Clinical characteristics of hemophagocytic syndrome: analysis of 46 cases / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the clinical manifestations, laboratory findings, treatment and prognosis of patients with hemophagocytic syndrome (HPS).</p><p><b>METHODS</b>A retrospective study was carried out to analyze the underlying disease, clinical characteristics, laboratory findings and outcomes of 46 patients with HPS.</p><p><b>RESULTS</b>This cohort included 19 cases of HPS secondary to cancer, 11 cases of HPS secondary to infection, 10 cases of suspected malignant lymphoma based on PET-CT findings (without biopsy), and 6 cases of unknown etiology. The coincidence rate of the clinical characteristics of the patients with the indices listed in HPS-2004 criteria were: fever (100%), elevated serum ferritin (100%), cytopenias (93.48%), splenomegaly (91.30%), hemophagocytosis in the bone marrow, spleen or lymph nodes (84.78%), hypofibrinogenemia (67.39%), and hypertriglyceridemia (54.05%). The cases of cancer, infections and unknown etiology showed significant differences in serum levels of ferritin and β2MG (P<0.05), and significant differences were found in triglycerides, LDH, and fibrinogenemia between the nonfatal and fatal cases (P<0.05).</p><p><b>CONCLUSION</b>HPS can be secondary to various underlying diseases, many associated with Epstein-Barr virus infection. Cancer, especially NK/T-cell lymphoma, is the main cause of HPS. Persistent fever, elevated serum ferritin level and cytopenias are the most sensitive indicators for diagnosis of HPS, and early diagnosis and treatment are critical to lower the mortality rate of this disease.</p>

Immunomodulatory effects of human amniotic versus bone marrow-derived mesenchymal stem cells on peripheral blood T lymphocytes in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the immunomodulatory effects of human amniotic mesenchymal stem cell (hAMSCs) and human bone marrow mesenchymal stem cells (hBMSCs) on peripheral blood T lymphocytes in an in vitro co-culture system.</p><p><b>METHODS</b>hAMSCs and hBMSCs isolated using enzymatic digestion and Ficoll-Hypaque density gradient centrifugation, respectively, were culture-expanded in vitro to obtain the 4th-generation cells. The two MSCs were co-cultured separately with human peripheral blood mononuclear cells stimulated with phytohemagglutinin (PHA-PBMSC) to investigate the changes in T lymphocyte subsets using flow cytomety and the production of interleukin-2 (IL-2) and IL-10 by the T lymphocytes using enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>Co-culture with either hAMSCs or hBMSCs significantly increased the proportions of Treg, Th2 and Tc2 and decreased Th1 and Tc1 cell subsets in the PBMCs as compared with the PBMCs cultured alone (P<0.05), and the changes in the PBMCs were similar between the two co-culture systems (P>0.05). In both of the two co-culture systems, IL-2 production by the lymphocytes was significantly lowered (P<0.05) and IL-10 production was significantly increased (P<0.05) as compared with their levels in the PBMCs cultured alone; no significant difference was found in IL-2 or IL-10 levels between the two co-culture systems (P>0.05).</p><p><b>CONCLUSION</b>The MSCs derived from human amnion and bone marrow have similar immunomodulatory effects on the T lymphocytes, suggesting the possibility of using hAMSCs in the treatment of graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.</p>

Comparison of Biological Characteristics and Immunosuppressive Activity between Human Amniotic Mesenchymal Stem Cells and Human Bone Marrow Mesenchymal Stem Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To compare the biological characteristics and immunosuppressive activity between human amniotic mesenchymal stem cells (hAMSC) and human bone marrow mesenchymal stem cells (hBMMSC).</p><p><b>METHODS</b>MSC from human amnion and bone marrow were isolated using enzymatic digestion and Ficoll-Hypaque density gradients, respectively. Their biological characteristics were compared by morphology, cell growth curves, cell cycle profile analysis, immunophenotype and immunofluorescence assay. Their immunosuppressive activities were studied on total activated T-cells with phytohemagglutinin (PHA-PBMSC). An in vitro co-culture was performed to compared the lymphocyte proliferation and the supernatant level of IFN-γ were measured by CCK-8 method and ELISA, respectively.</p><p><b>RESULTS</b>Both hAMSC and hBMMSC demonstrated fibroblast-like morphology. The hAMSC were able to be amplified for at least 15 passages, while the hBMMSC only for 6-7 passages. There was no significant difference in the proportion of G2/M phase cells of the 2 cells types (P>0.05). By FACS analysis for immunophenotype, both MSC were shown to be positive for CD105, CD90, CD73 and negative for CD34, CD45, CD11b, CD19, HLA-DR, but hAMSC were positive for Oct-3/4, which was in contrast to hBMMSC. Both of them expressed vimentin. Both the cells exhibited a inhibitory role on the lymphocyte proliferation induced by PHA in co-culture conditions, that was increased with the increase MSC proportion and both the suppressing effecs were enhanced. The supernatant IFN-γ levels of hAMSC co-cultured with lymphocyte at a ratio of 1:1 after 72 hours were measured by ELISA, and the level of IFN-γ was significantly lower than that in the same co-culture system of hBMMSC. In contrast to the IFN-γ in the PHA-stimulated group, the IFN-γ level in both co-culture groups was significantly lower.</p><p><b>CONCLUSION</b>MSC from amnion displayed a higher proliferative capacity and stem cell properties, compared with hBMMSC. Both MSC can inhibit lymphocyte proliferation and suppress IFN-γ secretion induced by PHA in vitro.</p>

Effect of simulated microgravity on erythroid differentiation of K562 cells and the mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of simulated microgravity on erythroid differentiation of K562 cells and explore the possible mechanism.</p><p><b>METHODS</b>The fourth generation rotating cell culture system was used to generate the simulated microgravity environment. Benzidine staining was used to evaluate the cell inhibition rate, and real-time quantitative PCR (qRT-PCR) was used to detect GATA-1, GATA-2, Ets-1, F-actin, β-Tubulin and vimentin mRNA expressions. The changes of cytoskeleton were observed by fluorescence microscopy, and Western blotting was employed to assay F-actin, β-tubulin and vimentin protein expression levels.</p><p><b>RESULTS</b>Benzidine staining showed that simulated microgravity inhibited erythroid differentiation of K562 cells. K562 cells treated with Hemin presented with increased mRNA expression of GATA-1 and reduced GATA-2 and Ets-1 mRNA expressions. Simulated microgravity treatment of the cells resulted in down-regulated GATA-1, F-actin, β-tubulin and vimentin mRNA expressions and up-regulated mRNA expressions of GATA-2 and Ets-1, and reduced F-actin, β-tubulin and vimentin protein expressions. Exposure to simulated microgravity caused decreased fluorescence intensities of cytoskeletal filament F-actin, β-tubulin and vimentin in the cells.</p><p><b>CONCLUSION</b>Simulated microgravity inhibits erythroid differentiation of K562 cells possibly by causing cytoskeleton damages to result in down-regulation of GATA-1 and up-regulation of GATA-2 and Ets-1 expressions.</p>

Rituximab-induced interstitial pneumonitis: report of two cases and literature review / 南方医科大学学报

We report two cases of rituximab (RTX)-induced interstitial pneumonia in two lymphoma patients receiving RTX treatment. Interstitial pneumonia was successfully managed in these two cases after a one-week-long intervention with corresponding treatments without affecting further treatment of the primary disease. RTX-induced interstitial pneumonia is characterized by a latent onset with an unclear pathological mechanism and absence of typical symptoms. High-resolution CT scan can provide valuable evidence for early diagnosis of RTX-induced interstitial pneumonia, which might be attributed partially to an increased susceptibility to P. jirovecii and fungal infection due to prolonged RTX treatment.