RESUMEN
Background: Kidney transplantation is the preferred treatment option for patients with end-stage renal disease. However, long-term graft survival remains a challenge. The enzyme indoleamine 2,3 dioxygenase (IDO) has been reported to have immunomodulatory effects with IDO transcripts being elevated in both antibody-mediated rejection and T cell-mediated rejection. Methods: A metal-conjugated antibody panel for the staining of kidney biopsies was developed, allowing the visualization of 41 structural and immune markers on a single tissue slide to gain in-depth insight into the composition and localization of the immune cell compartment. Staining was applied to week 4 and 24 protocol biopsies of 49 patients as well as on 15 indication biopsies of the TRITON study and 4 additional transplantation biopsies with glomerulitis. Results: A highly distinctive and specific glomerular IDO expression was observed in biopsies from 3 of 49 patients in imaging mass cytometry. Immunohistochemistry confirmed IDO expression in glomeruli of 10 of 10 cases with glomerulitis. IDO was found to be expressed by CD31+ glomerular endothelial cells, accompanied by the presence of granzyme-B+Tbet+CD7+CD45RA+ natural killer cells and CD68+ macrophages. Furthermore, a proportion of both the immune cells and endothelial cells expressed Ki-67, indicative of cell proliferation, which was not observed in control glomeruli. Conclusions: Our results show glomerular IDO expression in transplanted kidneys with glomerulitis, which is accompanied by increased numbers of natural killer cells and macrophages and likely reflects local immune activation.
RESUMEN
Tacrolimus is the backbone of immunosuppressive agents to prevent transplant rejection. Paradoxically, tacrolimus is nephrotoxic, causing irreversible tubulointerstitial damage. Therefore, infusion of mesenchymal stromal cells (MSC) 6 and 7 weeks post-transplantation was assessed to facilitate withdrawal of tacrolimus in the randomized phase II TRITON trial. Here, we performed detailed analysis of the peripheral blood immune composition using mass cytometry to assess potential effects of MSC therapy on the immune system. We developed two metal-conjugated antibody panels containing 40 antibodies each. PBMC samples from 21 MSC-treated patients and 13 controls, obtained pre-transplant and at 24 and 52 weeks post-transplantation, were analyzed. In the MSC group at 24 weeks, 17 CD4+ T cell clusters were increased of which 14 Th2-like clusters and three Th1/Th2-like clusters, as well as CD4+FoxP3+ Tregs. Additionally, five B cell clusters were increased, representing either class switched memory B cells or proliferating B cells. At 52 weeks, CCR7+CD38+ mature B cells were decreased. Finally, eight Tc1 (effector) memory cytotoxic T cell clusters were increased. Our work provides a comprehensive account of the peripheral blood immune cell composition in kidney transplant recipients after MSC therapy and tacrolimus withdrawal. These results may help improving therapeutic strategies using MSCs with the aim to reduce the use of calcineurin inhibitors. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT02057965.
Asunto(s)
Trasplante de Riñón , Células Madre Mesenquimatosas , Humanos , Tacrolimus , Trasplante de Riñón/métodos , Leucocitos Mononucleares , Inmunosupresores/uso terapéutico , Rechazo de InjertoRESUMEN
Although the immunological complexity of the maternal-fetal interface is well appreciated, the actual interaction of maternal immune cells and fetal trophoblasts is insufficiently understood. To comprehend the composition and spatial orientation of maternal immune cells and fetal extravillous trophoblasts, we applied imaging mass cytometry on decidua basalis of the three trimesters of healthy pregnancy. Within all trimesters, we observed considerably higher frequencies of myeloid cells in the decidua than is seen with single-cell suspension techniques. Moreover, they were the most pronounced cell type in the microenvironment of other decidual cells. In first trimester, HLA-DR- macrophages represented the most abundant myeloid subcluster and these cells were frequently observed in the vicinity of trophoblasts. At term, HLA-DR+ macrophage subclusters were abundantly present and frequently observed in the microenvironment of T cells. Taken together, our results highlight the dynamic role of myeloid cells at the human maternal-fetal interface throughout gestation.
RESUMEN
Inhibitors of the PD-1-PD-L1 axis have been approved as therapy for many human cancers. In spite of the evidence for their widespread clinical activity, little is known about the immunological alterations that occur in human cancer tissue after PD-1 blockade. We developed and employed a patient-derived tumor fragment platform to dissect the early immunological response of human tumor tissue to ex vivo PD-1 blockade. We observed that the capacity of immune cells to be reactivated ex vivo was predictive of clinical response, and perturbation analyses identified tumor-resident T cells as a key component of this immunological response. In addition, through combined analysis of baseline properties and immune response capacity, we identified a new subgroup of infiltrated tumors that lacks the capacity to respond to PD-1 blockade. Finally, the baseline presence of tertiary lymphoid structures and their components correlated with the capacity of cancers to undergo intratumoral immune cell reactivation.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Inhibidores de Puntos de Control Inmunológico/farmacología , Activación de Linfocitos/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Antineoplásicos Inmunológicos/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Linfocitos T CD8-positivos/citología , Diferenciación Celular/inmunología , Línea Celular Tumoral , Citocinas/análisis , Humanos , Activación de Linfocitos/inmunología , Linfocitos Infiltrantes de Tumor/citología , Neoplasias/inmunología , Microambiente Tumoral/inmunologíaRESUMEN
After renal transplantation, there is a need for immunosuppressive regimens which effectively prevent allograft rejection, while preserving renal function and minimizing side effects. From this perspective, mesenchymal stromal cell (MSC) therapy is of interest. In this randomized prospective, single-center, open-label trial, we compared MSCs infused 6 and 7 weeks after renal transplantation and early tacrolimus withdrawal with a control tacrolimus group. Primary end point was quantitative evaluation of interstitial fibrosis in protocol biopsies at 4 and 24 weeks posttransplant. Secondary end points included acute rejection, graft loss, death, renal function, adverse events, and immunological responses. Seventy patients were randomly assigned of which 57 patients were included in the final analysis (29 MSC; 28 controls). Quantitative progression of fibrosis failed to show benefit in the MSC group and GFR remained stable in both groups. One acute rejection was documented (MSC group), while subclinical rejection in week 24 protocol biopsies occurred in seven patients (four MSC; three controls). In the MSC group, regulatory T cell numbers were significantly higher compared to controls (p = .014, week 24). In conclusion, early tacrolimus withdrawal with MSC therapy was safe and feasible without increased rejection and with preserved renal function. MSC therapy is a potentially useful approach after renal transplantation.
Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Médula Ósea , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Estudios Prospectivos , TacrolimusRESUMEN
We describe an MHC class II (I-Ab)-restricted TCR transgenic mouse line that produces CD4+ T cells specific for Plasmodium species. This line, termed PbT-II, was derived from a CD4+ T cell hybridoma generated to blood-stage Plasmodium berghei ANKA (PbA). PbT-II cells responded to all Plasmodium species and stages tested so far, including rodent (PbA, P. berghei NK65, Plasmodium chabaudi AS, and Plasmodium yoelii 17XNL) and human (Plasmodium falciparum) blood-stage parasites as well as irradiated PbA sporozoites. PbT-II cells can provide help for generation of Ab to P. chabaudi infection and can control this otherwise lethal infection in CD40L-deficient mice. PbT-II cells can also provide help for development of CD8+ T cell-mediated experimental cerebral malaria (ECM) during PbA infection. Using PbT-II CD4+ T cells and the previously described PbT-I CD8+ T cells, we determined the dendritic cell (DC) subsets responsible for immunity to PbA blood-stage infection. CD8+ DC (a subset of XCR1+ DC) were the major APC responsible for activation of both T cell subsets, although other DC also contributed to CD4+ T cell responses. Depletion of CD8+ DC at the beginning of infection prevented ECM development and impaired both Th1 and follicular Th cell responses; in contrast, late depletion did not affect ECM. This study describes a novel and versatile tool for examining CD4+ T cell immunity during malaria and provides evidence that CD4+ T cell help, acting via CD40L signaling, can promote immunity or pathology to blood-stage malaria largely through Ag presentation by CD8+ DC.
Asunto(s)
Presentación de Antígeno , Linfocitos T CD4-Positivos/inmunología , Antígenos CD40/inmunología , Células Dendríticas/inmunología , Malaria/inmunología , Ratones Transgénicos/inmunología , Parasitemia/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Antígenos de Protozoos/inmunología , Antígenos CD40/deficiencia , Ligando de CD40/inmunología , Células Cultivadas , Cruzamientos Genéticos , Hibridomas , Activación de Linfocitos , Malaria Cerebral/inmunología , Malaria Cerebral/prevención & control , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos/genética , Plasmodium berghei/inmunología , Quimera por RadiaciónRESUMEN
Stem-cell-based repair of auditory neurons may represent an attractive therapeutic option to restore sensorineural hearing loss. Hair-follicle-bulge-derived stem cells (HFBSCs) are promising candidates for this type of therapy, because they (1) have migratory properties, enabling migration after transplantation, (2) can differentiate into sensory neurons and glial cells, and (3) can easily be harvested in relatively high numbers. However, HFBSCs have never been used for this purpose. We hypothesized that HFBSCs can be used for cell-based repair of the auditory nerve and we have examined their migration and incorporation into cochlear modiolus explants and their subsequent differentiation. Modiolus explants obtained from adult wild-type mice were cultured in the presence of EF1α-copGFP-transduced HFBSCs, constitutively expressing copepod green fluorescent protein (copGFP). Also, modiolus explants without hair cells were co-cultured with DCX-copGFP-transduced HFBSCs, which demonstrate copGFP upon doublecortin expression during neuronal differentiation. Velocity of HFBSC migration towards modiolus explants was calculated, and after two weeks, co-cultures were fixed and processed for immunohistochemical staining. EF1α-copGFP HFBSC migration velocity was fast: 80.5 ± 6.1 µm/h. After arrival in the explant, the cells formed a fascicular pattern and changed their phenotype into an ATOH1-positive neuronal cell type. DCX-copGFP HFBSCs became green-fluorescent after integration into the explants, confirming neuronal differentiation of the cells. These results show that HFBSC-derived neuronal progenitors are migratory and can integrate into cochlear modiolus explants, while adapting their phenotype depending on this micro-environment. Thus, HFBSCs show potential to be employed in cell-based therapies for auditory nerve repair.