Characterization of Th1- and Th2-associated chemokine receptor expression in spleens of patients with immune thrombocytopenia.

PURPOSE: In view of the numerous clinical observations and laboratory studies that suggest a critical role for the spleen in immune thrombocytopenia (ITP) pathophysiology, we aimed to characterize Th1-associated chemokine receptors CXCR3 and CCR5 and Th2-associated chemokine receptor CCR3 in spleens of ITP patients and assess the significance of their differential expression in the clinical setting. METHODS: The histopathology of spleens was observed using hematoxylin-eosin staining (HE), and the positive rate of CXCR3, CCR5 and CCR3 expression in spleens of 24 ITP patients and 12 patients with traumatic splenic rupture as normal controls was detected by immunohistochemistry using the SP method. CXCR3, CCR5 and CCR3 protein expression was analyzed by Western blot and mRNA levels were investigated by real-time polymerase chain reaction (RT-PCR). RESULTS: Reactive hyperplasia could be seen in follicles of the white pulp, the germinal central zone was enlarged and the marginal zone was thickened, the central arteries were thickened and fibrotic, and the density of the capillary vessel was increased in ITP patients. ITP group displayed a higher rate of expression of Th1-associated chemokine receptors CXCR3 and CCR5 (83.3% vs. 75%, 100% vs. 83.3%) but lower rate of expression of Th2-associated chemokine receptor CCR3 (50% vs. 66.7%) compared with the controls (P < 0.05, respectively). Western blot analysis revealed that CXCR3 and CCR5 protein expression was significantly increased in ITP patients while CCR3 was significantly reduced (P < 0.05, respectively). Meanwhile, ITP patients displayed increased mRNA levels of CXCR3 and CCR5 but decreased gene expression of CCR3 (P < 0.05, respectively). CONCLUSION: The data suggested that the abnormal expression of Th1/Th2 chemokine receptors may participate in splenic immune disorder in patients with ITP. Using corresponding inhibitors may inhibit Th1-dominant expression and mitigate the progress of the disease.

[Expression of CXCR3 and CCR5 chemokine receptor in spleens of patients with primary immune thrombocytopenia].

OBJECTIVE: To study CXCR3 and CCR5 chemokine receptor expression in spleens of patients with primary immune thrombocytopenia (ITP) and its clinical significance. METHODS: The splenectomy specimens from 10 ITP patients (ITP group) and 8 patients with traumatic splenic rupture (normal control group) were studied. Immunohistochemistry (IHC) was used to study the positive rate of CXCR3 and CCR5. Western blot was performed to detect CXCR3 and CCR5 protein expression, while real-time polymerase chain reaction (RT-PCR) was conducted to analyze their mRNA expression. RESULTS: The positive rate of CXCR3 and CCR5 were both higher in ITP group (90% and 100%, respectively) than those in control group (75% and 87.5%, respectively)(P < 0.05). The differences were statistically significant (P < 0.05). Protein and mRNA level of CXCR3 in ITP group were 3.0 and 3.5 times as high as those in control group, respectively. Those of CCR5 in ITP group were 1.2 and 1.7 times as high as those in control group, respectively. CONCLUSION: High expression of CXCR3 and CCR5 may play a part in the splenic immune disorders in patients with ITP.

[In vitro activation of bone marrow natural killer T cells of aplastic anemia patients].

OBJECTIVE: To investigate the quantitative and qualitative changes of TCRVα24(+)Vß11(+) natural killer T (NKT) cells from bone marrow (BM) of aplastic anemia (AA) after in vitro stimulation of α-galactosylceramide (α-Galcer). METHODS: NKT cells in the bone marrow mononuclear cells (BMMNCs) from either AA patients or healthy controls were enumerated with flow cytometry. BMMNCs were cultured in RPMI1640 medium supplemented with either α-Galcer and rhIL-2 or α-Galcer, rhIL-2 and rhG-CSF. The proliferative capacity of NKT cells was determined by NKT cell numbers before and after in vitro culture. Expression of intracellular IFNγ and IL-4 in activated NKT cells was analyzed with flow cytometry. RESULTS: In AA group, the percentage of NKT cells in BMMNCs was (0.19 ± 0.09)%. Addition of rhG-CSF into the α-Galcer/rhIL-2 culture medium resulted in significantly reduced expansion of NKT cells (67.45 ± 29.42-fold vs 79.91 ± 40.56 fold, P < 0.05). Meanwhile, addition of rhG-CSF reduced IFNγ positive NKT cells \[(37.45 ± 7.89)% vs (62.31 ± 14.67)%, P < 0.01\] and increased IL-4 positive NKT cells \[(55.11 ± 12.13)% vs (27.03 ± 9.88)%, P < 0.01\]. In healthy control group, the percentage of NKT cells in BMMNCs was (0.25 ± 0.12)%. Addition of rhG-CSF into the α-Galcer/rhIL-2 culture medium also significantly reduced expansion of NKT cells (97.91 ± 53.22-fold vs 119.58 ± 60.49-fold, P < 0.05), reduced IFNγ positive NKT cells \[(28.65 ± 10.63)% vs (50.87 ± 12.66)%, P < 0.01\], and increased IL-4 positive NKT cells \[(66.53 ± 14.96)% vs (31.11 ± 10.07)%, P < 0.01\]. CONCLUSION: Compared to those from healthy controls, BMMNCs from AA patiants have a reduced fraction of NKT cells, which possesses a decreased potential to expand in vitro in response to α-Galcer stimulation, and produce more IFNγ(+) NKT1 cells. rhG-CSF, in combination with α-Galcer, confers polarization of NKT cells towards IL-4(+) NKT2 subpopulation.

[Changes of gene expression profile in homoharringtonine-induced leukemia multi-drug resistant cell line K562/HHT].

OBJECTIVE: To study the resistant related molecules of human leukemia drug resistant K562 cells (K562/HHT) induced by homoharringtonine (HHT). METHODS: Gene expression profiles on K562/HHT, K562 and K562/HHT/RU486 (K562/HHT reversed by RU486) cells were detected by DNA microarray. The bone marrow tyrosine kinase gene in chromosome X (BMX) which changed dynamically among the three cells was confirmed by RT-PCR and Western blot. Then, BMX was transfected into K562 and K562/HHT cells, and the changes of daunorubicin (DNR) concentrations in these two cells were observed for BMX overexpression. RESULTS: As compared with K562, there were changes in 117 gene expressions in K562/HHT, 57 of which were up-regulated and 60 down-regulated. The mdrl gene was significantly up-regulated. When compared with K562/HHT, 50 significantly differently expressed genes were screened out in the K562/HHT/RU486 cells, of which up- and down-regulated genes were 13 and 37 respectively. These genes involved in drug resistance, cell signaling, cell differentiation, cell proliferation, transcription regulator, ion transport and so on. Four genes [NM-001721 (BMX), NM-031459 (SESN2), NM-033642 (FGF13) and AL-049309 (SFRS12)] expressed significantly differently in the two group cells, BMX gene expression was higher in K562/HHT, than in K562, but lower than in K562/HHT/RU486 as confirmed by RT-PCR and Western blot. After the plasmid pCI-neo-BMX was transfected into K562 and K562/HHT cells, DNR concentration was significantly lower (79.28 +/- 4.04, 29.84 +/- 2.67) than those before transfection (158.52 +/- 8.08, 58.58 +/- 6.53). CONCLUSION: BMX is associated with multi-drug resistance of K562/HHT cell line.

[Expression of specific antibodies against platelet glycoproteins in patients with mds and its significance].

The aim of this study was to find platelet specific autoantibodies against glycoproteins in myelodysplastic syndrome (MDS) and to explore its role in pathogenesis of MDS. The plasma autoantibodies against GP IIb/IIIa and GP Ib/IX were measured by using a modified monoclonal antibody specific immobolization platelet antigens assay (MAIPA). Absorbance greater than mean value plus tripled standard deviation recorded from the normal controls were regarded as positive. The results indicated that the total positive rate in patients with MDS was 16.67% (5/30), the total positive rate in patients with ITP was 46.67% (14/30), the difference between MDS group and ITP group was significant (P < 0.05). It is concluded that partial patients with MDS have plasma specific autoantibodies against platelet GP II b/III a and GP Ib/IX, indicating correlation of thrombocytopenia of patients with immune factors and the autoantibody-mediated platelet destruction may be involved in the pathogenesis of MDS. It provides a new basis for immunosuppression therapy for MDS.