[Application of Rapid Detection Method Based on NG-Test® CARBA 5 in Bloodstream Infections Associated With Carbapenem-Resistant Enterobacterales].

Objective: To compare the consistency and accuracy of a rapid test method and a traditional test method for pathogen identification, antimicrobial susceptibility and carbapenemase type identification of positive blood culture samples. Methods: A total of 51 positive blood culture samples of bloodstream infection (BSI) were collected between March 2022 and May 2022. All samples were found to be "positive for Gram-negative bacilli" according to the blood smear results. The rapid method was adopted to perform rapid antimicrobial susceptibility test (RAST) and analysis of the positive blood culture samples. According to the RAST result interpretation standards, NG-Test® CARBA 5 was used for rapid carbapenemase detection of the imipenem-resistant strains and the results were confirmed by PCR. In addition, mass spectrometry, VITEK 2 Compact drug sensitivity analysis, and carbapenemase type identification were performed with the colonies cultured with positive samples according to the traditional method. Results: In the identification of bacteria, the rapid method and the traditional method had 100% consistency rate in the identification results of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. In the antimicrobial susceptibility test, the consistency rate between the results of the two methods was high and the consistency rate for results for susceptibility to imipenem was 100%. In the identification of carbapenemase type, 18 serinase-producing strains and 3 metal-ß-lactamase-producing strains of Enterobacterales were detected by the traditional method. With the rapid method, 18 Klebsiella pneumoniae carbapenemase (KPC)-producing strains, 2 New Delhi metallo-betalactamase (NDM)-producing strains, and 1 imipenem enzyme (IMP)-producing strain were identified in the blood culture samples by using a testing kit. Compared with the PCR results, the sensitivity and specificity of the rapid test for determining carbapenemase types were 100%. In this study, we investigated a rapid method for bacteria and carbapenemase type identification of positive blood culture specimens and found that the turnaround time (TAT) of the rapid method was reduced by 1.94 days on average in comparison with the TAT of the traditional method. Conclusion: The rapid method established in the study can effectively shorten the TAT for pathogenic microorganism identification and antimicrobial susceptibility test of blood culture samples, and the joint report of colloidal gold carbapenemase type identification results can provide a reference for clinicians to use antibiotics appropriately and accurately manage multi-drug resistant bacterial infections.

[Sources of Klebsiella pneumoniae Isolated in a Hospital in the Past Decade and Trends and Changes of in vitro Drug Susceptibility].

Objective: To investigate the source of Klebsiella pneumoniae (KP) isolated in a hospital in the past decade and the in vitro drug susceptibility, and to provide clinical references for the treatment of KP-associated infection. Methods: The detection rate, the sources of the specimens, and in vitro susceptibility to antimicrobial agents of KP isolated from clinical specimens in a hospital between January 2012 and December 2021 were retrospectively analyzed. Resistance rate of the extended-spectrum ß-lactamases-producing isolates vs. that of the non-enzyme-producing ones, and the resistance rate of imipenem-resistant strains vs. that of imipenem-susceptible ones were compared and analyzed. Carbapenase inhibitor enhancement test was used to identify the types of the carbapenemases. Results: In total, 34 573 strains of KP were isolated from 1 684 668 clinical specimens, accounting for 14.6% of bacterial isolates. There were 16 888 non-repeated strains of KP. The main specimen sources of the isolates were sputum (10 274/16 888, 60.8%), blood (1 913/16 888, 11.3%) and urine (1 876/16 888, 11.1%). The proportion of extended-spectrum ß-lactamases-producing isolates increased from 29.6% (409/1 382) in 2012 to 38.9% (967/2 487) in 2021, and the resistance rate to antimicrobial agents was higher than that of non-enzyme-producing ones ( P<0.05). The proportion of imipenem-resistant strains increased from 3.2% (44/1 382) in 2012 to 23.4% (583/2 487) in 2021, and the resistance rate to antimicrobial agents was higher than that of imipenem-susceptible strains ( P<0.05). Serine carbapenase-producing strains accounted for 91.1% (920/1010). Conclusion: The resistance to antimicrobial agents of KP strains isolated from clinical specimens increased. It is necessary to monitor the in vitro drug susceptibility and the type of the carbapenemases of the isolates in order to provide guidance for the clinical usage of antibiotics.

[Whole Exome Sequencing Reveals Gene Mutation Characteristics of Primary Central Nervous System Lymphoma].

OBJECTIVE: To investigate gene mutation characteristics of primary central nervous system lymphoma (PCNSL) through whole exome sequencing (WES) to 18 patients with PCNSL. METHODS: Tumor tissues from 18 patients with diffuse large B-cell lymphoma who were diagnosed with PCNSL in Department of Hematology, Lanzhou University Second Hospital from September 2018 to December 2020 and had normal immune function, no history of HIV or immunosuppressant therapy were collected. High-throughput-based WES was performed on the tumor tissues, with an average sequencing depth of >100×. After data processing and bioinformatics analysis of sequencing results, the mutation maps and mutation characteristics of 18 PCNSL patients were obtained. RESULTS: Obvious somatic mutations were detected in all 18 patients. The median number of somatic mutations was 321. Missense mutations were most prominent (accounting for about 90%), and the mutation type was dominated by C>T (50.2%), reflecting the age-related mutation pattern. Among the top 15 frequently mutated genes, PSD3, DUSP5, MAGEB16, TELO2, FMO2, TRMT13, AOC1, PIGZ, SVEP1, IP6K3, and TIAM1 were the driver genes. The enrichment results of driver gene pathways showed that RTK-RAS, Wnt, NOTCH, Hippo and Cell-Cycle pathways were significantly enriched. The tumor mutation burden was between 3.558 48/Mb and 8.780 89/Mb, and the average was 4.953 32/Mb, which was significantly higher than other cancer research cohorts in the TCGA database. CONCLUSIONS: PCNSL occurs somatic missense mutations frequently, mainly point mutations, and the mutation type is mainly C>T. The driver genes are mainly involved in RTK-RAS, Wnt, NOTCH and Hippo pathways, indicating that the above pathways may be related to the pathogenesis of PCNSL. PCNSL has a significantly high tumor mutation burden, which may explain the efficacy of PD-1 inhibitors in PCNSL.

[Clinical Features and Prognostic of Patients with Primary Central Nervous System Lymphoma].

OBJECTIVE: To explore the clinical features and prognosis of patients with primary central nervous system lymphoma（PCNSL）. METHODS: A retrospective analysis was performed on the relationship between clinical features, treatment regimen and prognosis in 46 newly diagnosed patients with primary central nervous system lymphoma who were diagnosed and treated in The Second Hospital of Lanzhou University from January 2015 to September 2022. Fisher's exact probability method was used to analyze the differences in clinical data of different subgroups. Kaplan-Meier survival curve was used to analyze the overall survival rate and progression-free survival rate of patients with different treatments, and the factors influencing survival were analyzed. RESULTS: Among 46 patients with PCNSL, which pathological type were diffuse large B-cell lymphoma（DLBCL）. There were 26(56.5%) cases of male and 20(43.5%) of female, with a median age of 54(17-71) years. In Hans subtypes, 14 cases (30.4%) of GCB subtype, 32 cases (69.6%) of non-GCB subtype. 32 cases (69.6%) of Ki-67≥80%. Among 36 patients who completed at least 2 cycles of treatment with follow-up data, the efficacy evaluation was as follows: overall response rate(ORR) was 63.9%, complete response(CR) rate was 47.2%, 17 cases of CR, 6 cases of PR. The 1-year progression-free survival rate and 1-year overall survival rate was 73.6% and 84.9%, respectively. The 2-year progression-free survival rate and 2-year overall survival rate was 52.2% and 68.9%, respectively. The ORR and CR rate of 17 patients treated with RMT regimen was 76.5% and 52.9% (9 cases CR and 4 cases PR), respectively. Univariate analysis of 3 groups of patients treated with RMT regimen, RM-BTKi regimen, and RM-TT regimen as first-line treament showed that deep brain infiltration was associated with adverse PFS(P =0.032), and treatment regimen was associated with adverse OS in PCNSL patients（P =0.025）. CONCLUSION: Different treatment modalities were independent prognosis predictors for OS, the deep brain infiltration of PCNSL is a poor predictive factor for PFS. Patients with relapse/refractory (R/R) PCNSL have a longer overall survival time because to the novel medication BTKi. They have strong toleration and therapeutic potential as a first-line therapy for high-risk patients.

[The regulatory mechanism of songling xuemaikang capsule on PPARgamma in spontaneously hypertensive rats: an experimental study].

OBJECTIVE: To study the effect of Songling Xuemaikang Capsule (SXC) on blood pressure of spontaneously hypertensive rats (SHR) and regulatory mechanisms for peroxisome proliferator activated receptor-gamma (PPARgamma). METHODS: Totally 24 10-week-old SHR rats were randomly divided into the blank control group, the Chinese medicine (CM) group, and the Western medicine (WM) group, 8 in each group. Rats in the CM group were administered with SXC at the daily dose of 20 mg/kg by gastrogavage. Those in the WM group were administered with ramipril at the daily dose of 1 mg/kg by gastrogavage. Those in the blank control group were administered with equal volume of normal saline. The blood pressure was measured once per week. The cardiac ultrasound was performed 4 weeks later. Rats were killed and then blood was sampled from abdominal aorta. mRNA expressions of liver PPARgamma and angiotensin II type 1 receptor (AT1R) were detected by fluorescence real-time quantitative PCR. Protein expressions of PPARgamma and AT1R were detected using immunohistochemical assay (SP). The contents of PPARgamma and AT1R were quantitatively analyzed by Western blot. RESULTS: After 4 weeks of treatment, the blood pressure decreased in the CM group, showing statistical difference when compared with the blank control group (P < 0.01). CM was inferior to WM in lowering blood pressure. But as a whole, CM was more stable and could maintain blood pressure at a relatively stable level. The cardiac ejection fraction increased in the CM group, showing statistical difference when compared with the blank control group (P < 0.05, P < 0.01). The mRNA and protein expressions of liver PPARgamma were up-regulated in the CM group, showing statistical difference when compared with the blank control group (P < 0.05, P < 0.01). CM could obviously inhibit the AT1R mRNA expression, and down-regulate the protein expression of AT1R, showing statistical difference when compared with the blank control group and the WM group respectively (P < 0.01). CONCLUSION: SXC decreased blood pressure and improved the cardiac ejection fraction, which might be partially achieved by up-regulating the PPARgamma mRNA expression and protein synthesis, and inhibiting the AT1R mRNA expression and AT1R protein synthesis.

[The Prognostic Value of Prognostic Nutritional Index Combined with D-dimer in Patients with Diffuse Large B-Cell Lymphoma].

OBJECTIVE: To explore the effects of prognostic nutritional index (PNI) combined with D-dimer on the prognosis of patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). METHODS: The clinical data of 73 DLBCL patients at initial diagnosis were retrospectively evaluated, and the optimal cut-off point of PNI and D-dimer were determined by ROC curve. The overall survival (OS) rate and progression-free survival (PFS) rate in different subgroups were compared using Kaplan-Meier survival curves. Univariate and multivariate Cox regression analysis was performed to identify the factors associated with OS. RESULTS: Compared with the low PNI group (PNI<44.775), the high PNI group (PNI≥44.775) had better OS (P =0.022) and PFS (P =0.029), the 2-year OS rates of the two groups were 55.6% and 78.3% respectively (P =0.041). Compared with the high D-dimer group (D-dimer≥0.835), the low D-dimer group (D-dimer<0.835) had better OS (P <0.001) and PFS (P <0.001), the 2-year OS rates of the two groups were 51.4% and 86.8% respectively (P =0.001). Meanwhile, patients in the high PNI+ low D-dimer group had better OS (P =0.003) and PFS (P <0.001) than the other three groups, the 2-year OS rate was statistically different from the other three groups (P <0.05). The multivariate analysis revealed that NCCN-IPI (HR =2.083, 95%CI : 1.034-4.196, P =0.040), PNI (HR =0.267, 95%CI : 0.076-0.940, P =0.040) and PNI+D-dimer (HR =9.082, 95%CI : 1.329-62.079, P =0.024) were the independent risk factors affecting OS in patients with DLBCL. Subgroup analysis showed that PNI, D-dimer, and PNI combined with D-dimer could improve the prognostic stratification in low and low-intermediate risk DLBCL patients. CONCLUSION: High PNI, low D-dimer and combination of high PNI and low D-dimer at initial diagnosis suggest a better prognosis in DLBCL patients.

[A Prognostic Nomogram Based on Response to Bortezomib and BTK Expression for Treatment-Experienced Multiple Myeloma Patients].

OBJECTIVE: To establish a prognostic nomogram based on response to bortezomib and BTK expression for treatment-experienced multiple myeloma patients. METHODS: The Oncomine database was utilized to determine BTK expression, sex, age, albumin, Mayo index, response to bortezomib treatment, follow-up time and survival status in multiple myeloma(MM) patients. Cut-off point for BTK expression was calculated using R software. Univariate and multivariate analyses by Cox proportional hazards regression were then performed. Significant prognostic factors were combined to build a nomogram. The discrimination ability and predictive accuracy of the nomogram were evaluated using the index of concordance (C-index) and calibration curves. RESULTS: Multivariate analysis showed that response to bortezomib, BTK expression and sex were independent risk factors for prognosis. The C-index value of the nomogram made according to the independent risk factors was 0.729 (95%CI, 0.642-0.8164). The calibration curves showed good consistency between predicted and actual survivals for 1-year and 2-year overall survival. CONCLUSION: The proposed nomogram is accurate in predicting the prognosis of patients with MM.

[Prognostic Value of A New Risk Stratification Model (R2-ISS) in Newly Diagnosed Multiple Myeloma].

OBJECTIVE: To investigate the significance of a new risk stratification model (R2-ISS) in evaluating the prognosis of newly diagnosed multiple myeloma (MM). METHODS: Clinical data of 116 newly diagnosed MM patients admitted to Lanzhou University Second Hospital from June 2012 to March 2021 were retrospectively analyzed. According to R2-ISS, these patients were divided into four groups: low risk, low-intermediate risk, intermediate-high risk, and high risk. The significance of R2-ISS on prognosis of the patients was analyzed. RESULTS: Survival analysis showed that R2-ISS was associated with progression-free survival (PFS) (P=0.042) and overall survival (OS) (P=0.014). Cox univariate analysis showed that lactate dehydrogenase, serum calcium, serum creatinine, ß2-microglobulin, ISS, R-ISS, R2-ISS, t(4;14), and autologous hematopoietic stem cell transplantation (ASCT) were the influencing factors of OS in newly diagnosed MM patients (all P<0.05). Cox multivariate analysis showed that R-ISS, R2-ISS, and ASCT were independent risk factors affecting OS (all P<0.05). In addition, survival analysis of patients with different R2-ISS showed that ASCT improved PFS and OS. CONCLUSION: R2-ISS has prognostic value for newly diagnosed MM patients, while ASCT can improve the prognosis of patients with different R2-ISS.

[The Influence of CONUT Score on the Prognosis of Patients with Multiple Myeloma].

OBJECTIVE: To explore the influence of controlling nutritional status (CONUT) score on the prognosis of newly diagnosed patients with multiple myeloma (MM). METHODS: The clinical data 119 patients with MM who were diagnosed according to the international myeloma diagnostic criteria in Lanzhou University Second Hospital from April 2010 to October 2018 were collected and retrospectively analyzed. The relationship between clinical indexes, including age, sex, MM type, absolute lymphocyte count (ALC), absolute neutrophil count (ANC), absolute monocyte count (AMC), hemoglobin (Hb), platelet (PLT), ß2-microglobulin (ß2-MG), lactate dehydrogenase (LDH), albumin (ALB), globulin (GLO), cholesterol (CHO), serum creatinine (Scr), etc, and CONUT score was discussed to explore the prognostic value of these indicators. SPSS 25.0 software was used for statistical analysis. Progression-free survival(PFS) and overall survival (OS) between different subgroups were calculated by Kaplan-Meier curves and difference between survival curves was detected by Log-rank tests. Receiver operating characteristic (ROC) curve was used to estimate the most discriminative cutoff value of CONUT score for predicting OS. Mann-Whitney U test was used for non-parametric samples, and chi-square test for categorical variables. Univariate and multivariate analysis were performed by using COX proportional hazards model to identify factors associated with OS. RESULTS: Compared with high-scoring group, low-scoring group had a better OS ï¼»median OS was 43.3 months and 127.67 months, respectively, 95% confidence interval (CI): 57.065-78.345, P=0.038ï¼½. At the same time, the low-scoring group also had higher level of ALC, ANC, AMC, Hb, PLT, ALB, and CHO but lower of GLO. Multivariate survival analysis showed that age (HR=1.027, 95%CI: 1.000-1.054, P=0.048), AMC (HR=11.284, 95%CI: 22.968-42.897, P<0.001), CONUT score (HR=1.198, 95%CI: 1.036-1.385, P=0.015), M protein (non-IgG/IgG type) type (HR=0.503, 95%CI: 0.259-0.977, P=0.043) were independent factors affecting the prognosis of MM patients. CONCLUSION: The CONUT score as an immune-nutrition score is a convenient and easy-to-obtain index to effectively predict the prognosis of MM patients.

[Value of Red Blood Cell Distribution Width and Fibrinogen Level for Evaluation of the Therapeutic Efficacy and Prognosis in Patients with Diffuse Large B-Cell Lymphoma].

OBJECTIVE: To investigate the value of red blood cell distribution width (RDW) and fibrinogen (Fib) level for the evaluation of therapeutic efficacy and prognosis in patients with diffuse large B-cell lymphoma (DLBCL). METHODS: The relationship between RDW/Fib at initial diagnosis and efficacy and the clinical outcome was retro-spectively analyzed based on the study of 105 patients with DLBCL. The patients were divided into two groups: low RDW group (≤15%) and high RDW group (>15%), low Fib group (Fib≤4 g/L) and high Fib group (Fib>4 g/L) according to the normal values of RDW and Fib. Therapeutic efficacy, overall survival (OS) time and progression free survival (PFS) time were compared between two groups. The correlation between each factors and efficacy, prognosis was analyzed by univariate and multivariate regression. RESULTS: The therapeutic efficacy (P<0.001), OS time(P=0.004), and PFS time(P=0.007) were poorer in the high RDW group as compared with the low RDW group. The efficacy (P=0.015) and PFS time(P=0.04) were poorer in the high Fib group as compared with the low Fib group. Multivariate analysis showed that high RDW was the independent risk factor for efficacy of DLBCL patients (OR=3.394, 95% CI 1.093-10.539, P=0.035). CONCLUSION: High RDW and high Fib associate with poor efficacy in DLBCL patients.

Genomic and Transcriptomic Characterization of Natural Killer T Cell Lymphoma.

Natural killer/T cell lymphoma (NKTCL) is an aggressive and heterogeneous entity of non-Hodgkin lymphoma, strongly associated with Epstein-Barr virus (EBV) infection. To identify molecular subtypes of NKTCL based on genomic structural alterations and EBV sequences, we performed multi-omics study on 128 biopsy samples of newly diagnosed NKTCL and defined three prominent subtypes, which differ significantly in cell of origin, EBV gene expression, transcriptional signatures, and responses to asparaginase-based regimens and targeted therapy. Our findings thus identify molecular networks of EBV-associated pathogenesis and suggest potential clinical strategies on NKTCL.

[Killing activity of co-cultured cytokine-induced killer cells and dendritic cells against multi-drug resistant tumor cell lines].

OBJECTIVE: A lot of studies have suggested that a certain amount of T cells may be involved among cytokine-induced killer (CIK) cells. The aim of the present study was to prove whether an antigen-specific killing effect on tumor cells is involved during the CIKs-induced killing process. METHODS: Bone marrow mononuclear cells (BMMNCs) derived from healthy subjects were separately cultured to generate dendritic cells (DC) and CIKs. A human mammary cancer cell line MCF-7/ADR, expressing P-gp antigen, was frozen-thawed and the lysate including P-gp antigen was obtained. The DC pulsed with or without tumor antigen lysate was co-cultured with CIK (pulsed-DC + CIK and DC + CIK), and CIK cultured alone was used as control. The cell phenotype of DC and CIK was analyzed by flow cytometry. The secretion of IL-12 and IFN-gamma was assayed by ELSA. The antitumor effect of the three CIK groups targeted at MCF-7/ADR cells expressing P-gp antigen and MCF-7 cells was detected by MTT. RESULTS: Pulsed-DC + CIK group and DC + CIK group showed a higher expression level of DC mature phenotypes than those before co-culture with CIK, with a significant difference (P = 0.003, P = 0.001, respectively). The phenotypes (CD3, CD8, CD56) of CIK in pulsed-DC + CIK group and DC + CIK group was higher than those in CIK group (P = 0.003, P = 0.011, respectively). Among the three CIK groups, pulsed-DC + CIK group had the highest phenotypes on CD3+ CD56 (pulsed-DC + CIK vs. DC + CIK, P = 0.001; pulsed-DC + CIK vs. CIK, P < 0.001) and CD3 CD8 (P = 0.002, P = 0.002, respectively). Among the three groups, the pulsed-DC + CIK group showed the lowest CD45RA phenotype (pulsed-DC + CIK vs. DC + CIK, P < 0.001; pulsed-DC + CIK vs. CIK, P = 0.004). Among the three groups the secretion of IL-12 and IFN-gamma had the highest level in pulsed-DC + CIK group, with a value of 254 +/- 14.5 pg/ml and 3100 +/- 286 pg/ml, respectively. The antitumor killing effect on MCF-7/ADR cells had a significant difference between any two groups (pulsed-DC + CIK VS. DC + CIK, P = 0.039; pulsed-DC + CIK VS. CIK, P = 0.002; DC + CIK vs. CIK, P = 0.049). The highest was in pulsed-DC + CIK group and the lowest was in CIK group. The CIK group showed a significantly lower antitumor effect on MCF-7 cells than the other two groups (pulsed-DC + CIK vs. CIK, P = 0.007; DC + CIK vs. CIK, P = 0.048), but no significant difference between the pulsed-DC + CIK and DC + CIK groups. CONCLUSION: In the present study, DC and CIK cells have been successfully obtained and cultured from bone marrow mononuclear cells. After their co-culture, not only both their specific phenotypes were increased, but also the associated cytokines were secreted. An improved antitumor killing effect and some possible specific immunocytotoxicity were observed. Our findings provided a basis for experimental and clinical research on bio-immunotherapy targeted at multi-drug resistant tumor cells.

[Effect of plasmacytoid dendritic cells activited by bacteria on spontaneous remission of leukemia].

Spontaneous remission (SR) of leukemia is a rare event in clinic, which possibly correlated with severe infection and sepsis, but its exact mechanism has not been confirmed. Plasmacytoid dendritic cells (pDC) and myeloid dendritic cells (mDC) play a key role in innate and adaptive immunity respectively. A patient with severe infection of staphylococcus aureus acquired completely spontaneous remission (SR), moreover a increased number of pDC were observed, suggesting that bacteria-activated pDC may play an important role in SR. This study was purposed to explore if the bacteria can stimulate pDC successfully and get a functional pDC. Both pDC and mDC were isolated from freshly collected, leukocyte-rich buffy coats from healthy blood donor and leukemic patient with SR by using MACS and FACS. The pDC were cultured in RPMI 1640 medium and were stimulated with different kinds of bacteria and the expression of CD40, CD86 and HLA-DR on the cell surface was analyzed by flow cytometry. The cytokine (IFN-α, IL-12, IFN-γ, IL-2, IL-4, IL-10) production was measured by using ELISA kits. The results showed that the stimulation with staphylococcus aureus and pseudomonas aeruginosa resulted in the maturation of pDC, which secrete a large number of IFN-α and promote the differentiation of naive CD4⁺ T cells to Th1 cells. The activated pDC expressed high level of CD40 and CD86 and showed higher T cell stimulatory capacities. It is concluded that staphylococcus aureus and pseudomonas aeruginosa can activate pDC, the activated pDC secrete high quantity of IFN-α. This result suggests that bacteria stimulated pDC may play a key role in SR of leukemia following severe infections.

[Effect of high dose dexamethasone on function and TLR-9 mRNA expression of plasmacytoid dendritic cells in patients with immune thrombocytopenic purpura].

This study was purposed to investigate the effect of high-dose dexamethasone (DXM) on function and Toll like receptor 9 (TLR-9) expression of plasmacytoid dendritic cells (pDC) in peripheral blood of patients with immune thrombocytopenic purpura (ITP). 15 newly diagnosed patients with ITP received high dose DXM at single daily doses of 40 mg for 4 consecutive days. The peripheral blood plasmacytoid dendritic cells from 13 remission patients and 15 normal controls were separated by immunomagnetic beads and then induced by CpG-OND2216. 24 h later, the levels of IFN-α, IL-6 and TNF-α in the supernatant were detected by enzyme linked immunosorbent assay (ELISA). The expression of TLR9 mRNA of pDC was detected by real-time quantitative PCR. The results indicated that the levels of IFN-α, IL-6 and TNF-α produced by pDC in ITP patients were significantly higher than those in normal controls (P < 0.05). After high dose DXM treatment, the levels of IFN-α, IL-6 and TNF-α decreased without significant difference compared with normal controls (P > 0.05). The expression of TLR9 mRNA in pDC of untreated patients was significantly higher than that in control group (P < 0.05), and significantly reduced after treatment without difference from that in control group (P > 0.05). It is concluded that pDC may play an important role in ITP by their TLR9 and secreted cytokines; dexamethasone may down regulate the expression of TLR9, inhibit pDC function, and thus play a therapeutic role.

[The immune effects of rituximab on dendritic cells derived from patients with primary immune thrombocytopenia].

OBJECTIVE: To explore the changes of surface antigen and function of rituximab on dendritic cells derived from patients with Primary immune thrombocytopenia (ITP) to further understand the effective mechanism of immunotherapy. METHODS: The peripheral blood mononuclear cells (PBMCs) were isolated from remission patients with ITP before and after low-dose rituximab infusion, and the PMNCs were stimulated for 5 days by rhGM-CSF and rhlL-4 in 5% CO2 air at 37°C incubator. Then all of DCs were cultured with TNF-α for 48 hours. The morphology of DCs was monitored under inverted microscope daily, and the surface antigens of the DCs were analysed by flow cytometry, meanwhile the levels of IL-12p70 and TGF-ß1 in supernatants were detected by ELISA, mix lymphocyte reaction was performed by MTT assay. RESULTS: (1) Rituximab-treated-DCs showed no obvious tree-like protruding compared with untreated-DCs. The former cells were small and most of nucleus were centric. (2) The expressions of HLA-DR, CD80, CD83 and CD86 on rituximab-treated-DCs \[56.37 ± 3.95)%, (36.41 ± 2.82)%, (30.45 ± 4.61)% and (41.98 ± 4.17)%, respectively\] were significantly lower than those untreated-DCs \[(73.71 ± 7.61)%, (55.14 ± 7.30)%, (80.91 ± 7.09)% and (59.03 ± 3.43)%, respectively\](all P < 0.05), the concentration of IL-12p70 was significantly lower, \[(66.87 ± 4.29)% vs (50.17 ± 14.52)%\], while that of TGF-ß1 \[(9.70 ± 0.31)%\] higher than the untreated-DCs \[(2.70 ± 0.36)%\] (P < 0.05). (3) The abilities to activate T cells proliferation of rituximab-treated-DCs reduced compared with untreated-DCs. CONCLUSION: The surface antigen of ITP-DCs and the concentration of IL-12p70 reduced after the low-dose rituximab infusion. The abilities to activate T cells proliferation reduced while the concentration of TGF-ß1 increased. Rituximab may achieve its therapeutic effect on ITP by downregulating the immunoreactivity of DCs.

[The prevalence of Th17 cells in patients with acute myeloid leukemia].

OBJECTIVE: To investigate the proportion of Th17 cells in the peripheral blood of the patients with acute myeloid leukemia (AML) and evaluate the potential association of Th17 cells with AML. METHODS: The cytokines IL-17 and TGF-ß1 in the peripheral blood of AML patients before therapy (group 1), AML patients in complete remission (AML-CR, group 2) and healthy donors (group 3) were measured by enzyme-linked immunosorbent assay (ELISA). The proportion of Th17 cells of each group was evaluated by flow cytometry. The level of IL-17 mRNA of each group was examined by reverse transcription-PCR (RT-PCR). RESULTS: The percentage of Th17 cells and the level of IL-17, IL-17 mRNA in group 1 \[(10.502 ± 1.071) ng/L, (0.935 ± 0.140)% and 0.262 ± 0.510\] and group 2 \[(11.345 ± 0.987) ng/L, (1.091 ± 0.159)% and 0.307 ± 0.031\] was significantly lower than that in group 3 \[(16.852 ± 1.198) ng/L, (2.586 ± 0.235)% and 0.501 ± 0.060\]. The percentage of Th17 cells and the level of IL-17, IL-17 mRNA in group 1 was lower than that in the group 2. But the level of TGF-ß1 in the group 1 (29.963 ± 1.588) ng/L and the group 2 (25.163 ± 1.848) ng/L was significantly higher than that in group 3 (13.366 ± 1.565) ng/L. However, the level of TGF-ß1 in the group 3 was higher than that of the group 2. CONCLUSION: Th17 cells might be negatively correlated with the AML development. The overexpression of TGF-ß1 in AML patients might suppress the differentiation of Th17 cells.

[In vitro cytokines-induced differentiation in mononuclear cell derived dendritic cells from chronic myeloid leukemia].

The purpose of this study was to investigate the mechanism of effects of interferon-alpha (IFN-alpha) on chronic myeloid leukemia (CML). Bone marrow mononuclear cells (BMMNC) were obtained from heparinized blood of CML patients by Ficoll-Paque density gradient centrifugation. The expressions of CD1a, CD83, CD86, HLA-ABC, HLA-DR and CD54 on DC induced by IFN-alpha + GM-CSF, IFN-alpha + GM-CSF+IL-4 and IL-4 + GM-CSF for 7 days in vitro were assayed by flow cytometry. The morphologic features were observed by transmission and optical microscopy. The mixed lymphocyte reactions (MLR) with DC were evaluated by MTT assay. The results showed that the DC cultured in different cytokine combinations expressed significantly higher levels of CD1a, HLA-ABC, HLA-DR, CD86, CD54, and CD83 than those in the precultured. The DC growing with IFN-alpha + GM-CSF expressed significantly higher levels of HLA-ABC, HLA-DR than those in GM-CSF + IL-4. The CD86 expression and MLR levels in IFN-alpha + GM-CSF + IL-4 increased significantly. The expression rate of DC antigens and MLR in the IFN resistant group significantly lower than those in the newly diagnosed and the effectively treated groups after at least 6 months of IFN-alpha treatment (P < 0.05). The DC from the IFN resistant group did not express significantly CD86 and MLR in IFN-alpha + GM-CSF + IL-4 groups compared to those in the newly diagnosed and IFN effective treated groups. It is concluded that the BMMNC from CML cultured in combination with IFN-alpha and other cytokines can be induced into DC with typical morphologic and immunophenotypic characteristics. Addition of IFN-alpha + GM-CSF + IL-4 to DC cultures can significantly up-regulate the expression of major histocompatibility complex molecules, co-stimulatory molecules and various adhesion molecules. The deficiency of DC differentiation and function may play a role in the development of clinical resistance to IFN-alpha.

[In vitro inducing differentiation of bone marrow mononuclear cells of chronic myeloid leukemia].

BACKGROUND & OBJECTIVE: Interferon-alpha (IFN-alpha), an important immunoregulatory cytokine, has been widely used in treating virus hepatitis, lymphoma, and chronic myeloid leukemia (CML), and showed evident effect, but the mechanism is unclear. Dendritic cells (DCs), specialized antigen-presenting cells (APCs), play a pivotal role in activating initial T cells, and maintaining cell immune responses. Does the efficiency of IFN to CML relate to the DCs induced by IFNy What kind of effect do DCs have on IFN therapy for CMLy Up to now, few researches are available. This study aimed to observe whether the DCs were induced through culturing bone marrow mononuclear cells (BMMNCs) of CML in vitro, investigate the mechanism of IFN-alpha therapy for CML, and then provide a new strategy for clinical therapy. METHODS: BMMNCs were obtained from blood of CML patients by Ficoll-Paque density gradient centrifugation, and induced with IFN-alpha and granulocyte-macrophage colony-stimulating factor (GM-CSF) (IFN-alpha/ GM-CSF group), or interleukin-4 (IL-4) and GM-CSF (IL-4/ GM-CSF group), or IFN-alpha, GM-CSF, and IL-4 (IFN-alpha/GM-CSF/IL-4 group) for 7 days. Morphology of BMMNCs was observed under transmissional and optical microscope. The phenotypes [CD1a, CD83, CD86, human leukocyte antigen (HLA)-ABC, HLA-DR, CD54] were assayed by flow cytometry (FCM). The mixed lymphocyte reaction(MLR) of DCs was evaluated by MTT assay. RESULTS: After inducements, BMMNCs showed typical dendritic projections, and highly expressed CD1a, CD83, CD86, HLA-ABC, HLA-DR, and CD54. Positive rates of HLA-ABC and HLA-DR were higher in IFN-alpha/ GM-CSF group and IFN-alpha/GM-CSF/IL-4 group than in IL-4/ GM-CSF group (P<0.05). Positive rate of CD86 and MLR were the highest in IFN-alpha/GM-CSF/IL-4 group (P<0.05). Positive rates of DC antigens and MLR in IFN-resistant group were significantly lower than those in newly diagnosed group and IFN-sensitive group (P<0.05), but positive rate of CD86 and MLR have no significant difference among 3 groups in the presence of IFN-alpha/GM-CSF/IL-4 (P>0.05). CONCLUSIONS: The BMMNCs of CML cultured in the presence of IFN-alpha and other cytokines can be induced into DCs with morphologic and immunophenotypic characteristics, overexpresses major histocompatibility complex (MHC) molecules, co-stimulatory molecules, and adhesion molecules, and have enhancing MLR. The possible mechanism of IFN-alpha therapy for CML may be relate to DCs.