Project description:Background: We aimed to investigate the effects of intravenous immune globulin (IVIG) and rituximab desensitization treatment on kidney transplant rate and blood gene expression profiles by microrarrays. Methods: We enrolled patients with PRA levels >50% and on the deceased-donor waiting list for >5 years. Patients received IVIG (2.0 g/kg) on day 0 and 30; and rituximab (375 mg/m2) on day 15. The antibodies with mean fluorescence intensity (MFI) values > 5,000 were reported to UNET as unacceptable antigens. The gene expression profiles of blood samples collected in PAXGene tube were studied by Affymetrix HuGene 1.0 ST expression arrays. Results: 40 of the 415 patients (10%) on the waiting list were eligible for desensitization treatment and 11 completed the treatment. While 15 of the remaining 29 patients (52%) received a transplant without therapy, only 2 of the 11 desensitized patients (18%) received transplant during a median follow-up of 217 days. While there were no statistically significant difference in demographics, desensitized patients had higher cPRA values (97% vs. 77%, p=0.0005) and more number of unacceptable antigens (39 vs. 10, p=0.0001). There was no significant change in the mean number of unacceptable antigens (39 ± 22 versus 39 ± 23) or reduction in the mean MFI values (11,333 ± 3,133 vs 11,289 ± 3,386). Analysis of genes chosen as significantly differentially expressed revealed downregulation of genes involved in B cells and immune system (CD79a, B and T lymphocyte associated transcript, B cell scaffold protein, CD22, CXCR5, fas apoptotic inhibitory protein). Gene set enrichment analysis using Pathogenesis Based Transcripts created by Edmonton Group demonstrated significant downregulation of B cell associated (p=0.04) and immunoglobulin transcripts (p=0.03). Conclusion: Although, desensitization with IVIG and rituximab decreases the expression of B cell and immunoglobulin associated transcripts, it was not successful in increasing kidney transplant rate or in decreasing the number of unacceptable antigens. Total of 28 arrays included in this study, which corresponding to 9 individuals with paired pre/post treatment samples and an additional 10 untreated control individuals. pair_analysis_normData.txt for paired analysis of pre/post treatment; ordinary_analysis_normData.txt for non-paired analysis include all samples, except for 38 Pax V0 and 56 Pax V1, which shows technicial bias and lowest array quality, hence removed from analysis.
Project description:Background: We aimed to investigate the effects of intravenous immune globulin (IVIG) and rituximab desensitization treatment on kidney transplant rate and blood gene expression profiles by microrarrays. Methods: We enrolled patients with PRA levels >50% and on the deceased-donor waiting list for >5 years. Patients received IVIG (2.0 g/kg) on day 0 and 30; and rituximab (375 mg/m2) on day 15. The antibodies with mean fluorescence intensity (MFI) values > 5,000 were reported to UNET as unacceptable antigens. The gene expression profiles of blood samples collected in PAXGene tube were studied by Affymetrix HuGene 1.0 ST expression arrays. Results: 40 of the 415 patients (10%) on the waiting list were eligible for desensitization treatment and 11 completed the treatment. While 15 of the remaining 29 patients (52%) received a transplant without therapy, only 2 of the 11 desensitized patients (18%) received transplant during a median follow-up of 217 days. While there were no statistically significant difference in demographics, desensitized patients had higher cPRA values (97% vs. 77%, p=0.0005) and more number of unacceptable antigens (39 vs. 10, p=0.0001). There was no significant change in the mean number of unacceptable antigens (39 ± 22 versus 39 ± 23) or reduction in the mean MFI values (11,333 ± 3,133 vs 11,289 ± 3,386). Analysis of genes chosen as significantly differentially expressed revealed downregulation of genes involved in B cells and immune system (CD79a, B and T lymphocyte associated transcript, B cell scaffold protein, CD22, CXCR5, fas apoptotic inhibitory protein). Gene set enrichment analysis using Pathogenesis Based Transcripts created by Edmonton Group demonstrated significant downregulation of B cell associated (p=0.04) and immunoglobulin transcripts (p=0.03). Conclusion: Although, desensitization with IVIG and rituximab decreases the expression of B cell and immunoglobulin associated transcripts, it was not successful in increasing kidney transplant rate or in decreasing the number of unacceptable antigens.
Project description:Immune profiles were performed retrospectively in highly sensitized kidney transplant candidates Our hypothesis was that baseline differences in immune profiles could help identify candidates that respond to desensitization therapy. Single-cell mass cytometry by time-of-flight (CyTOF) phenotyping, gene arrays, and phosphoepitope flow cytometry were performed in 20 highly sensitized kidney transplant candidates undergoing desensitization therapy.
Project description:Background: Plasmapheresis/rituximab-based desensitization therapy has successfully reduced anti-ABO antibody levels and suppressed antibody-mediated rejection (AMR) in ABO-incompatible (ABOi) kidney transplantation (KT). However, high titers of anti-ABO antibodies in some patients are refractory to standard desensitization, leading to loss of KT opportunities or AMR. Methods: Eculizumab-based desensitization was used to rescue high-titer ABOi KT patients refractory to plasmapheresis/rituximab-based desensitization. Results: The initial titers of anti-ABO IgG antibodies in the two patients were 1:512 and >1:1024; the final pre-transplant titers after desensitization were 1:128 and 1:64. Both patients received eculizumab from the day of KT to two or four weeks post-KT and maintained stable renal function up to one-year post-transplantation without overt infectious complications, despite early episodes of suspicious AMR or borderline T cell-mediated rejection. Molecular phenotype analysis of allograft biopsies using the Banff Human Organ Transplant gene panel revealed that gene expression patterns in the ABOi KT with eculizumab group overlapped with those in the ABOi KT with AMR group more than in the ABOi KT without AMR group, except for complement pathway-related gene expression. Anti-ABO antibody titers decreased to low levels 1–3 months post-transplant in the eculizumab group in parallel with decreasing anti-B-specific B cells at this time point. Conclusions: Short-term eculizumab-based desensitization therapy is promising for rescuing ABOi KT recipients with unacceptably high anti-ABO antibody titers refractory to plasmapheresis-based desensitization therapy.
Project description:Immune profiles were performed retrospectively in highly sensitized kidney transplant candidates Our hypothesis was that baseline differences in immune profiles could help identify candidates that respond to desensitization therapy.
Project description:Rituximab/chemotherapy relapsed and refractory B cell lymphoma patients have a poor overall prognosis, and it is urgent to develop novel drugs for improving the therapies of these patients. A new oral histone deacetylase inhibitor, chidamide shows anti-tumor activity by activating the pro-apoptosis pathway in some other hematological malignancies, suggesting its potential application to the relapsed and refractory B cell lymphoma. In this study, we examined the therapeutic effects of chidamide on the cell and mouse models of the rituximab/chemotherapy resistant B cell lymphoma, as well as the primary B cell lymphoma cells. In Raji-4RH and RL-4RH cells, the rituximab/chemotherapy resistant B cell lymphoma cell lines (RRCL), chidamide treatment induced growth inhibition and G0/G1 cell cycle arrest, which were associated with E2F1/2 inactivation and CDK2 degradation. The primary B cell lymphoma cells from Rituximab/chemotherapy relapsed and refractory patients were also very sensitive to chidamide treatment. Interestingly, chidamide triggered the cell death via the autophagy pathway instead of the activation of apoptosis in Raji-4RH and RL-4RH cells, likely due to the lack of the pro-apoptotic proteins in these resistant cells. In the RNA-seq and chromatin immunoprecipitation (ChIP) analysis, we identified BTG1 and FOXO1 as the direct target genes of chidamide, which control the autophagy and cell cycle respectively in RRCL treated with chidamide. Moreover, the combination of chidamide with the chemotherapy drug Cisplatin sensitized the RRCL to growth inhibition in a synergistic manner. Chidamide-Cisplatin combination significantly reduced the tumor burden of a mouse lymphoma model established with engraftment of RRCL. Taken together, our studies provides a theoretic and mechanistic basis for further evaluation of the chidamide-based clinical trial for rituximab/chemotherapy relapsed and refractory B cell lymphoma patients.
Project description:Objective: Rituximab displays therapeutic benefits in the treatment of rheumatoid arthritis (RA) patients resistant to TNF blockade. However, the precise role of B cells in the pathogenesis of RA is still unknown. In this study we investigated the global molecular effects of rituximab in synovial biopsies obtained from anti-TNF resistant RA patients before and after administration of the drug. Methods: Paired synovial biopsies were obtained from the affected knee of anti-TNF resistant RA patients before (T0) and 12 weeks after initiation of rituximab therapy (T12). Total RNA was extracted, labeled according to standard Affymetrix procedures and hybridized on GeneChip HGU133 Plus 2.0 slides. Immunohistochemistry and quantitative real-time PCR experiments were performed to confirm the differential expression of selected transcripts. Results: According to paired Student’s t-tests, 549 out of 54,675 investigated probe sets were differentially expressed between T0 and T12. Pathway analysis revealed that genes down-regulated between T0 and T12 were significantly enriched in immunoglobulin genes, and genes involved in chemotaxis, leucocyte activation and immune responses (Gene Ontology annotations). By contrast, genes up-regulated between T0 and T12 were significantly enriched in transcripts involved in cell development (Gene Ontology annotation) and wound healing (GSEA). At baseline, higher synovial expression of immunoglobulin genes was associated with response to therapy. Conclusion: Rituximab displays unique effects on global gene expression profiles in synovial tissue of RA patients. These observations open new perspectives in the understanding of the biological effects of the drug and in the selection of patients likely to benefit from this therapy.
Project description:Systemic sclerosis (SSc) shows complex clinical manifestations including progressive skin and internal organ fibrosis. SSc can be divided into 'intrinsic subsets' by gene expression suggesting patient-specific heterogeneity in pathogenesis or temporal evolution of disease. Here we validate these subsets using an independent patient population, and test whether the genes vary over time with patients changing subsets as disease progresses, or if the genes are a stable feature of the patients within each subset. Skin biopsies were analyzed from 13 dSSc patients enrolled in an open label study of rituximab, 9 dSSc patients not treated with rituximab, and 9 healthy controls. These data recapitulate the patient 'intrinsic subsets' described previously with gene expression associated with cell proliferation, inflammatory processes, and a normal-like group. Serial skin biopsies showed consistent and non-progressing gene expression. We were unable to detect significant differences in gene expression before and after rituximab treatment, consistent with an apparent lack of clinical response. Serial biopsies from each patient stayed within the same gene expression subset regardless of treatment regimen or the time point at which they were taken. This demonstrates the intrinsic subsets are an inherent, reproducible and stable feature of SSc that is independent of disease duration. Skin biopsies were analyzed from 13 dSSc patients enrolled in an open label study of rituximab, 9 dSSc patients not treated with rituximab, and 9 healthy controls.
Project description:This study is the first of this kind performed on minor salivary glands (mSG) of patients with Sjögren’s Syndrome. It shows that B cells clones are able to circulate across different glands and once re-seeded in a different mSG to continue the process of somatic hypermutation and switching of the immunoglobulin genes. Understanding B cells behavior in organs affected by autoantibodies, may help in designing personalized therapies, using monoclonal antibodies that target B cells (e.g. Rituximab) only on those patients that have a higher chance to respond.