[Specific changes in gut microbiota and short-chain fatty acid levels in infants with cow's milk protein allergy]. / ç‰›å¥¶è›‹ç™½è¿‡æ•å©´å„¿è‚ é“èŒç¾¤ç‰¹å¼‚æ€§å˜åŒ–åŠçŸ­é“¾è„‚è‚ªé ¸æ°´å¹³åˆ†æž.

OBJECTIVES: To explore the changes in gut microbiota and levels of short-chain fatty acids (SCFA) in infants with cow's milk protein allergy (CMPA), and to clarify their role in CMPA. METHODS: A total of 25 infants diagnosed with CMPA at Children's Hospital Affiliated to Zhengzhou University from August 2019 to August 2020 were enrolled as the CMPA group, and 25 healthy infants were selected as the control group. Fecal samples (200 mg) were collected from both groups and subjected to 16S rDNA high-throughput sequencing technology and liquid chromatography-mass spectrometry to analyze the changes in gut microbial composition and metabolites. Microbial diversity was analyzed in conjunction with metabolites. RESULTS: Compared to the control group, the CMPA group showed altered gut microbial structure and significantly increased α-diversity (P<0.001). The abundance of Firmicutes, Clostridiales and Bacteroidetes was significantly decreased, while the abundance of Sphingomonadaceae, Clostridiaceae_1 and Mycoplasmataceae was significantly increased in the CMPA group compared to the control group (P<0.001). Metabolomic analysis revealed reduced levels of acetic acid, butyric acid, and isovaleric acid in the CMPA group compared to the control group, and the levels of the metabolites were positively correlated with the abundance of SCFA-producing bacteria such as Faecalibacterium and Roseburia (P<0.05). CONCLUSIONS: CMPA infants have alterations in gut microbial structure, increased microbial diversity, and decreased levels of SCFA, which may contribute to increased intestinal inflammation.

REGγ Mitigates Radiation-Induced Enteritis by Preserving Mucin Secretion and Sustaining Microbiome Homeostasis.

Radiation-induced enteritis, a significant concern in abdominal radiation therapy, is associated closely with gut microbiota dysbiosis. The critical mucus layer plays a pivotal role in preventing the translocation of commensal and pathogenic microbes. Although the significant expression of REGγ in intestinal epithelial cells is well established, its role in modulating the mucus layer and gut microbiota remains enigmatic. The current study revealed notable changes in gut microorganisms and metabolites in irradiated mice lacking REGγ, as opposed to wild-type mice. Concomitant with gut microbiota dysbiosis, REGγ deficiency facilitated the infiltration of neutrophils and macrophages, thereby exacerbating intestinal inflammation after irradiation. Furthermore, fluorescence in situ hybridization assays unveiled an augmented proximity of bacteria to intestinal epithelial cells in REGγ knockout mice after irradiation. Mechanistically, deficiency of REGγ led to diminished goblet cell populations and reduced expression of key goblet cell markers, Muc2 and Tff3, observed in both murine models, minigut organoid systems and human intestinal goblet cells, indicating the intrinsic role of REGγ within goblet cells. Interestingly, although administration of broad-spectrum antibiotics did not impact the alteration of goblet cell numbers and MUC2 secretion, it effectively attenuated inflammation levels in the ileum of irradiated REGγ absent mice, aligning them with their wild-type counterparts. Collectively, these findings highlight the crucial contribution of REGγ in counteracting radiation-triggered microbial imbalances and cell-autonomous regulation of mucin secretion.

The prognostic value of CD8+ CTLs, CD163+ TAMs, and PDL1 expression in the tumor microenvironment of primary central nervous system lymphoma.

To explore immune cell infiltration and PDL1 expression in the tumor microenvironment (TME) of primary central nervous system lymphoma (PCNSL), we performed immunohistochemical staining on paraffin-embedded tumor tissues from 34 patients diagnosed with PCNSL. CD8 and CD163 positive cells were manually counted, and PDL1 expression was quantified by the H-score scoring method in the tumor center and around the tumor. The Kaplan-Meier method was used to analyze the prognostic value of the TME. We found obvious infiltration of CD8+ CTLs and CD163+ TAMs in the TME of PCNSL patients. And PDL1 was expressed in the tumor center as well as around the tumor. Survival analysis showed that high CD8+ CTLs levels and high intratumoral PDL1 expression were significantly correlated with longer OS. High CD8+ CTLs and CD163+ TAMs levels were associated with longer PFS.

[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.

Impairment of intestinal barrier associated with the alternation of intestinal flora and its metabolites in cow's milk protein allergy.

Cow's milk protein allergy (CMPA), one of the most prevalent food allergies, seriously affects the growth and development of infants and children with the rising incidence and prevalence. The dysbiosis of intestinal flora acts to promote disease including allergic disease. Therefore, studying the role of intestinal flora in allergic diseases holds great promise for developing effective strategies to mitigate the risk of food allergies. This study aims to elucidate the role of disrupted intestinal flora and its metabolites in children with CMPA.16S rDNA sequence analysis was applied to characterize the changes in the composition of intestinal flora. The findings revealed heightened diversity of intestinal flora in CMPA, marked by decreased abundance of Firmicutes and Bacteroidetes, and increased abundance of Proteobacteria and Actinobacteria. Furthermore, metabolite analysis identified a total of 1245 differential metabolites in children with CMPA compared to those in healthy children. Among these, 765 metabolites were down-regulated, while 480 were up-regulated. Notably, there were 10 negative differential metabolites identified as bile acids and derivatives, including second bile acids, such as deoxycholic acid, ursodeoxycholic acid and isoursodexycholic acid. The intestinal barrier was further analyzed and showed that the enterocytes proliferation and the expression of Claudin-1, Claudin-3 and MUC2 were down-regulated with the invasion of biofilm community members in the CMPA group. In summary, these findings provide compelling evidence that food allergies disrupt intestinal flora and its metabolites, consequently damaging the intestinal barrier's integrity to increase intestinal permeability and immune response.

Quercetin Mitigates Radiation-Induced Intestinal Injury and Promotes Intestinal Regeneration via Nrf2-Mediated Antioxidant Pathway1.

Radiation-induced intestinal injury is one the most common adverse events of radiotherapy, which can severely affect quality of life. There are currently no effective preventive and therapeutic options for this disorder. Quercetin is a natural flavonoid found in common food species, with the characteristics of antioxidative, anti-inflammatory, and anti-cancerous activity. However, the role of quercetin on radiation-induced intestinal injury and the underlying mechanism remains poorly understood. In this study, we found quercetin treatment can improve the survival rate of mice after a single-dose (10 Gy) abdominal irradiation. Quercetin-pretreated mice significantly reduced radiation-induced DNA damage and intestinal epithelium cell apoptosis. In addition, quercetin also improved the proliferation activity of intestinal stem cells and promoted intestine epithelium repair after irradiation. Further studies demonstrated that quercetin treatment curtailed radiation-induced reactive oxygen species generation via regulating Nrf2 signaling in intestinal epithelium cells. Furthermore, treatment with Nrf2 inhibitor, could reverse the above effects. Altogether, quercetin can ameliorate radiation-induced intestine injury via regulating Nrf2 signaling, scavenging free radicals, and promoting intestinal epithelium repair.

Frequent Gene Mutations and Their Possible Roles in the Pathogenesis, Treatment and Prognosis of Primary Central Nervous System Lymphoma.

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma with poor prognosis. In recent years, the emergence of genetic subtypes of systematic diffuse large B-cell lymphoma has highlighted the importance of molecular genetics, but large-scale research on the molecular genetics of PCNSL is lacking. Herein, we summarize the frequent gene mutations and discuss the possible pathogenesis of PCNSL. Myeloid differentiation primary response gene 88 (MYD88) and CD79B mutations, which cause abnormal activation of noncanonical nuclear factor-κB, are prominent genetic abnormalities in PCNSL. They are considered to play a major role in the pathogenesis of PCNSL. Other genes, such as caspase recruitment domain family member 11 (CARD11), tumor necrosis factor alpha induced protein 3 (TNFAIP3), transducin (ß)-like 1 X-linked receptor 1, cyclin dependent kinase inhibitor 2A, PR domain zinc finger protein 1, and proviral insertion in murine malignancies 1, are also frequently mutated. Notably, the pathogenesis of immune insufficiency-associated PCNSL is related to Epstein-Barr virus infection, and its progression may be affected by different signaling pathways. The different mutational patterns in different studies highlight the heterogeneity of PCNSL. However, existing research on the molecular genetics of PCNSL is still limited, and further research into PCNSL is required to clarify the genetic characteristics of PCNSL.

The novel HLA-DQB1*03:499N allele identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-DQB1*03:499N differs from HLA-DQB1*03:01:01:01 by one nucleotide in exon 2.

[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.

[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.

Retraction: The lnc-SNHG1 Gene Is Overexpressed and Correlates with Increased White Blood Cell Count, Poor Induction Treatment Response, and Poor Survival Profile in Adult Acute Myeloid Leukemia

Objective: Long noncoding RNA small nucleolar RNA host gene 1 (lnc-SNHG1) is involved in leukemogenesis via mediating multiple pathways. The current study aimed to further explore its clinical roles in disease risk, clinical features, and prognosis in patients with acute myeloid leukemia (AML). Materials and Methods: A total of 161 adult AML patients, 50 patients as a disease control (DC) group, and 50 healthy individuals as a healthy control (HC) group were enrolled and bone marrow mononuclear cells were collected. Subsequently, reverse transcriptionquantitative polymerase chain reaction (RT-qPCR) was performed to measure lnc-SNHG1 expression. Results: Lnc-SNHG1 expression was higher in AML patients than in the DC and HC groups (both p<0.001), with good value in distinguishing AML patients from DC and HC individuals (area under the curve of 0.726 and 0.884, respectively). Moreover, lnc-SNHG1 expression was positively associated with white blood cell (WBC) count (p=0.008) but was not correlated with other clinical features such as cytogenetics, molecular genetics, and risk stratification (all p>0.05). Lnc-SNHG1 expression was also associated with a lower complete remission (CR) rate (p=0.001). Patients with lnc-SNHG1 expression in the fourth quantile had the worst CR rates compared to patients with lnc-SNHG1 expressions in the first, second, and third quantiles (all p<0.05). Furthermore, lnc-SNHG1 expression was correlated with unsatisfactory event-free survival (p<0.001) and overall survival (p=0.002), which were worst in patients with lnc-SNHG1 expression in the fourth quantile compared to patients with lnc-SNHG1 expressions in the first, second, and third quantiles (all p<0.05). Conclusion: Lnc-SNHG1 overexpression is associated with elevated WBC count, poor induction treatment response, and poor survival profile in cases of AML and it may serve as a potential indicator for AML.

Nontargeted and targeted metabolomics approaches reveal the key amino acid alterations involved in multiple myeloma.

PURPOSE: Multiple myeloma (MM), a kind of malignant neoplasm of clonal plasma cells in the bone marrow, is a refractory disease. Understanding the metabolism disorders and identification of metabolomics pathways as well as key metabolites will provide new insights for exploring diagnosis and therapeutic targets of MM. METHODS: We conducted nontargeted metabolomics analysis of MM patients and normal controls (NC) using ultra-high-performance liquid chromatography (UHPLC) combined with quadrupole time-of-flight mass spectrometry (Q-TOF-MS) in 40 cases of cohort 1 subjects. The targeted metabolomics analysis of amino acids using multiple reaction monitoring-mass spectrometry (MRM-MS) was also performed in 30 cases of cohort 1 and 30 cases of cohort 2 participants, to comprehensively investigate the metabolomics disorders of MM. RESULTS: The nontargeted metabolomics analysis in cohort 1 indicated that there was a significant metabolic signature change between MM patients and NC. The differential metabolites were mainly enriched in metabolic pathways related to amino acid metabolism, such as protein digestion and absorption, and biosynthesis of amino acids. Further, the targeted metabolomics analysis of amino acids in both cohort 1 and cohort 2 revealed differential metabolic profiling between MM patients and NC. We identified 12 and 14 amino acid metabolites with altered abundance in MM patients compared to NC subjects, in cohort 1 and cohort 2, respectively. Besides, key differential amino acid metabolites, such as choline, creatinine, leucine, tryptophan, and valine, may discriminate MM patients from NC. Moreover, the differential amino acid metabolites were associated with clinical indicators of MM patients. CONCLUSIONS: Our findings indicate that amino acid metabolism disorders are involved in MM. The differential profiles reveal the potential utility of key amino acid metabolites as diagnostic biomarkers of MM. The alterations in metabolome, especially the amino acid metabolome, may provide more evidences for elucidating the pathogenesis and development of MM.

Correlation analysis of long non-coding RNA TUG1 with disease risk, clinical characteristics, treatment response, and survival profiles of adult Ph- Acute lymphoblastic leukemia.

BACKGROUND: Long non-coding RNA taurine-upregulated gene 1 (lncRNA TUG1) is reported to be involved in the progression and development of several malignancies; however, its role in Philadelphia chromosome-negative acute lymphoblastic leukemia (Ph- ALL) is unknown. The present study aimed to explore the correlation of lncRNA TUG1 with disease risk, disease condition, and prognosis of adult Ph- ALL. METHODS: Total 101 adult Ph- ALL patients and 40 bone marrow (BM) donors were included, followed by detection of BM monocyte cell lncRNA TUG1 expression by reverse transcription-quantitative polymerase chain reaction. According to the quantiles of lncRNA TUG1 expression in Ph- ALL patients, these patients were divided into four tiers: tier 1 (ranked in 0%~25%), tier 2 (ranked in 25%~50%), tier 3 (ranked in 50%~75%), and tier 4 (ranked in 75%~100%). RESULTS: LncRNA TUG1 was upregulated in Ph- ALL patients compared with healthy donors. Further analysis indicated that in Ph- ALL patients, higher lncRNA TUG1 tier was correlated with the presence of central nervous system leukemia, increased white blood cell level, and bone marrow blasts. Furthermore, higher lncRNA TUG1 tier was negatively associated with complete remission (CR) within 4 weeks, total CR, and allogeneic hematopoietic stem cell transplant achievement. In addition, higher lncRNA TUG1 tier was associated with decreased disease-free survival and overall survival, which was further verified to be an independent factor by Cox's regression analysis. CONCLUSION: lncRNA TUG1 presents potential to be a novel biomarker for disease risk assessment and survival surveillance in Ph- ALL management.

[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.

Prognostic significance of peripheral monocytic myeloid-derived suppressor cells and monocytes in patients newly diagnosed with diffuse large b-cell lymphoma.

OBJECTIVE: The revised International Prognostic Index (R-IPI) aids in predicting the prognosis of patients with diffuse large B cell lymphoma (DLBCL), but R-IPI yields no significant differences in assessing different subtypes of DLBCL. It is necessary to identify patients with a high-risk of DLBCL and alternative therapy should be delivered as early as possible. METHODS: In total, 144 patients newly diagnosed with DLBCL including 63 GCB-DLBCL and 81 non-GCB-DLBCL and 30 healthy controls were enrolled. Peripheral monocytic myeloid-derived suppressor cells (M-MDSC) (CD14(+)HLA(-)DR(low/-)) were detected by flow cytometry and the percentage of monocytes (MΦ) was evaluated by completed blood count (CBC). The correlation between M-MDSC% and MΦ% was statistically analyzed. RESULTS: Compared with healthy controls, significant increase was observed in M-MDSC% and MΦ% in DLBCL patients (both P<0.001). Significant difference of M-MDSC% was found between GCB-DLBCL and non-GCB-DLBCL patients in both poor (P<0.001) and very good groups (P=0.03), whereas no statistical significance in the good group (P>0.05). The MΦ% in non-GCB-DLBCL patients was significantly higher than that in GCB-DLBCL counterparts merely in the poor group (P<0.001). Positive correlation was noted between MΦ% and M-MDSC in all DLBCL patients rather than in healthy controls (r=0.227 P=0.229). CONCLUSION: The percentage of peripheral MΦ was positively correlated with M-MDSC% in patients with different subtypes and risks of DLBCL. Peripheral MΦ% and M-MDSC% combined with R-IPI score may be useful for predicting the prognosis of patients newly-diagnosed with DLBCL.

[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.

[Immuno-effect of plasmacytoid dendritic cells on bacteria infection induced spontaneous remission of leukemia].

OBJECTIVE: To explore the immuno-effect of plasmacytoid dendritic cells (pDC) on bacteria infection induced spontaneous remission (SR) of leukemia. METHODS: Both pDC and myeloid dendritic cells (mDC) were isolated and purified from leukemic patient with SR and healthy donor by combination of immunomagnetic beads and flow cytometry. pDC were cultured in RPMI1640 medium and stimulated with different bacteria. The T cells proliferation was detected by MTT, and cytokine production by ELISA kits. RESULTS: The human bacterial pathogen Staphylococcus aureus and Pseudomonas aeruginosa stimulation for 48 h resulted in the maturation of pDC with production of high quantity of IFN-α at (15.34 ± 2.91) ng/ml and (10.38 ± 1.41) ng/ml, respectively, comparing with that of negative group at (1.36 ± 0.13) ng/ml (P<0.01). Activated pDC could promote the differentiation of naive CD4⁺ T cells to Th1 cells with secretion of IFN-γ at (2.16 ± 0.37) ng/ml and (2.73 ± 1.11) ng/ml, respectively, comparing with that of positive control at (2.55 ± 0.23) ng/ml (P > 0.05). Activated pDC showed higher T cell stimulatory capacities [proliferation index (PI) was 4.36 and 4.05, respectively] than that of non-activated pDC (PI was 1.23 and 0.13, respectively) (P < 0.01). CONCLUSION: Staphylococcus aureus and Pseudomonas aeruginosa activated pDC may play a key role in SR of leukemia following severe infections.

[Effect of astragalus polysaccharide on sensitivity of leukemic cell line HL-60 to NK cell cytotoxicity and its mechanism].

The objective of this study was to explore the effect of astragalus polysaccharide (APS) on sensitivity of leukemic cell line HL-60 to NK cell cytotoxicity and its mechanism. The cytotoxicities of NK cells against HL-60 cells were analyzed by LDH releasing assay at different effect-to-target cell ratios (E:T) before and after treated with APS. The gene expression of MHC class I chain-related (MICA) in HL-60 cells before and after APS treatment was assayed with RT-PCR. Protein expression of MICA in HL-60 cells was assayed by flow cytometry before and after treated by APS. The results showed that after treated with APS 15 mg/ml for 48 h, the cytotoxicities of NK cells against HL-60 cells enhanced at different effect-to-target (P < 0.05), and the gene and protein expressions in MICA of HL-60 cells were up-regulated (P < 0.05). It is concluded that the APS can obviously up-regulate the expression of MICA in HL-60 cells, thus enhance sensitivity of HL-60 cells to cytotoxicity of NK cells.

[Anti-tumor immune response of dendritic cells derived from lymphoma cells transduced with recombinant adenovirus encoding human P53].

This study was aimed to investigate the immunological effect of modified dendritic cells (DC) which inducing cytotoxic T cells (CTL) against lymphoma cells. The DC were isolated from the lymph node and peripheral blood of patients with diffuse large B cell lymphoma (DLBCL). DC were transfected with recombinant adenovirus vector carrying human p53 gene (rAd-p53-DC). The expression of p53 gene was detected by flow cytometry. Western-blot was used to detect the expression of P53. ELISA was used to detect IL-12 level in supernatant. The mixed lymphocyte reaction (MLR) was used to detect the proliferative ability of auto-lymphocyte stimulated by DC. The lactate dehydrogenase (LDH) release test was used to determine the cytotoxicity of CTL. The results indicates that the expressions of DC surface molecule (except for CD1a) such as CD83, CD80, CD86 and HLA-DR were significantly higher in experiment group than that in control group and blank control group. The secretion of IL-12 in supernatant was higher in experiment group than that in control group. The autologous T lymphocyte proliferation and cytotoxic activity against the same kind of DLBL-cells increased in experiment group as compared with control group and blank control group (P < 0.05). The ability to stimulate T lymphocyte proliferation increased with the rising of the ratio of DC and T lymphocyte. However, there was statistically significant difference between rAd-p53-DC derived from Lymph node and peripheral blood (P < 0.05). It is concluded that rAd-p53-transfected DC can induce CTL response in vitro against lymphoma cells.