ABSTRACT: 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: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:Systems biology approach to examine effects of seasonal flu vaccination in adults of different ages on gene expression, cytokine stimulation and serum cytokines with parameters such as immune senescence to uncover new markers and mechanisms behind failure of immune function in many older people. 1. Combinatorial tetramer analysis by FACS and/or CyTOF; Phosphoflow. 2. Luminex; Gene expression profiling (Affymetrix microarray). 3. Luminex; Gene expression profiling (Affymetrix microarry); Microneutralization assays. 4. Gene expression profiling (Affymetrix microarray); Immune phenotyping by CyTOF. 5. Gene expression profiling (Affymetrix microarray). 6. Immune phenotyping by CyTOF; Luminex. 7. ELISA.
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: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:In this study we employed transcriptome mRNA profiling of whole blood and purified CD4, CD8 T cells, B cells and monocytes in tandem with high-throughput flow cytometry in 10 kidney transplant patients sampled serially pre-transplant, 1, 2, 4, 8 and 12 weeks. We then mechanistically deconvoluted the early post-transplant immune response. The flow cytometry data confirms depletion of specific cell subsets in response to ATG induction and immunosuppression with sustained decreases in CD4 as well as CD8 cell subsets. A series of T cell activation markers were expressed from Pre-Tx to 12 weeks indicating the evolution of immunity including expansion of CD45RO+CD62L- effector memory cells. Serial whole blood transcript monitoring demonstrated over 2000 differentially expressed genes, with over 80 percent down-regulated Post-Tx. However, cell subset analysis revealed a unique spectrum of subset-specific gene expression with time-dependent changes, with contrasting significant Post-Tx gene upregulation. Our results provide a unique view of the complex evolution of immune/inflammatory molecular networks marking the early post transplant immune response. A critical finding is that analysis of the constituent blood cell subsets provides an entirely new level of detail revealing the nature of this process, effectively deconvoluting the changes that are otherwise lost in the noise of cellular complexity of whole blood. Keywords: kidney transplantation, peripheral blood, DNA microarrays, acute kidney rejection, cell subsets, flow cytometry, serial monitoring We employed Affymetrix HG-U133 Plus 2.0 GeneChips for mRNA profiling of whole blood and purified CD4, CD8 T cells, B cells and monocytes in tandem with high-throughput flow cytometry in 10 kidney transplant patients sampled serially pre-transplant, 1, 2, 4, 8 and 12 weeks. We then mechanistically deconvoluted the early post-transplant immune response.
Project description:In this study, investigators recruited the largest reported cohort of tolerant kidney transplant recipients who maintained their graft after ceasing to take their immunosuppression drug, and compared this cohort to subjects with stable allograft function while on immunosuppression and healthy non transplated, controls. Using gene expression studies, they identified genetic markers that are strong candidates for predicting kidney transplant candidates who may benefit from minimization or withdrawl of immunosuppression. Microarrays were used to detect expressed gene profiles of whole-blood total RNA from subjects in the tolerant, standard immunotherapy and healthy control participants
Project description:Kidney transplant recipients are at particular risk for developing tumors, many of which are now routinely treated with immune checkpoint inhibitors (ICIs); however, ICI therapy can precipitate transplant rejection. We utilized TCR sequencing to identify and track alloreactive T cells in a patient with melanoma who experienced kidney transplant rejection following ICI therapy. ICI therapy was associated with a sharp increase in circulating alloreactive CD8+ T cell clones, many of which were also detected in the rejected kidney but not at tumor sites. Longitudinal and cross-tissue TCR analyses revealed unintended expansion of alloreactive CD8+ T cells induced by ICI therapy for cancer, coinciding with ICI-associated organ rejection.
Project description:Kidney transplant recipients are at particular risk for developing tumors, many of which are now routinely treated with immune checkpoint inhibitors (ICIs); however, ICI therapy can precipitate transplant rejection. We utilized TCR sequencing to identify and track alloreactive T cells in a patient with melanoma who experienced kidney transplant rejection following ICI therapy. ICI therapy was associated with a sharp increase in circulating alloreactive CD8+ T cell clones, many of which were also detected in the rejected kidney but not at tumor sites. Longitudinal and cross-tissue TCR analyses revealed unintended expansion of alloreactive CD8+ T cells induced by ICI therapy for cancer, coinciding with ICI-associated organ rejection.
Project description:Kidney transplant recipients are at particular risk for developing tumors, many of which are now routinely treated with immune checkpoint inhibitors (ICIs); however, ICI therapy can precipitate transplant rejection. We utilized TCR sequencing to identify and track alloreactive T cells in a patient with melanoma who experienced kidney transplant rejection following ICI therapy. ICI therapy was associated with a sharp increase in circulating alloreactive CD8+ T cell clones, many of which were also detected in the rejected kidney but not at tumor sites. Longitudinal and cross-tissue TCR analyses revealed unintended expansion of alloreactive CD8+ T cells induced by ICI therapy for cancer, coinciding with ICI-associated organ rejection.