RESUMO
Antigen-specific immunotherapy combats autoimmunity or allergy by reinstating immunological tolerance to target antigens without compromising immune function. Optimization of dosing strategy is critical for effective modulation of pathogenic CD4(+) T-cell activity. Here we report that dose escalation is imperative for safe, subcutaneous delivery of the high self-antigen doses required for effective tolerance induction and elicits anergic, interleukin (IL)-10-secreting regulatory CD4(+) T cells. Analysis of the CD4(+) T-cell transcriptome, at consecutive stages of escalating dose immunotherapy, reveals progressive suppression of transcripts positively regulating inflammatory effector function and repression of cell cycle pathways. We identify transcription factors, c-Maf and NFIL3, and negative co-stimulatory molecules, LAG-3, TIGIT, PD-1 and TIM-3, which characterize this regulatory CD4(+) T-cell population and whose expression correlates with the immunoregulatory cytokine IL-10. These results provide a rationale for dose escalation in T-cell-directed immunotherapy and reveal novel immunological and transcriptional signatures as surrogate markers of successful immunotherapy.
Assuntos
Autoantígenos/administração & dosagem , Linfócitos T CD4-Positivos/efeitos dos fármacos , Dessensibilização Imunológica/métodos , Encefalomielite Autoimune Experimental/terapia , Peptídeos/administração & dosagem , Transcriptoma/efeitos dos fármacos , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Autoantígenos/química , Autoantígenos/imunologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Anergia Clonal/efeitos dos fármacos , Misturas Complexas/administração & dosagem , Misturas Complexas/imunologia , Relação Dose-Resposta Imunológica , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/imunologia , Regulação da Expressão Gênica , Receptor Celular 2 do Vírus da Hepatite A , Injeções Subcutâneas , Interleucina-10/genética , Interleucina-10/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Peptídeos/química , Peptídeos/imunologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Proteínas Proto-Oncogênicas c-maf/genética , Proteínas Proto-Oncogênicas c-maf/imunologia , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores Virais/genética , Receptores Virais/imunologia , Medula Espinal/química , Transcriptoma/imunologia , Proteína do Gene 3 de Ativação de LinfócitosRESUMO
Most studies on Salmonella enterica serovar Typhimurium infection focus on strains ATCC SL1344 or NTCC 12023 (ATCC 14028). We have compared the abilities of these strains to induce membrane ruffles and invade epithelial cells. S. Typhimurium strain 12023 is less invasive and induces smaller membrane ruffles on MDCK cells compared with SL1344. Since the SPI-1 effector SopE is present in SL1344 and absent from 12023, and SL1344 sopE mutants have reduced invasiveness, we investigated whether 12023 is less invasive due to the absence of SopE. However, comparison of SopE(+) and SopE(-) S. Typhimurium strains, sopE deletion mutants and 12023 expressing a sopE plasmid revealed no consistent relationship between SopE status and relative invasiveness. Nevertheless, absence of SopE was closely correlated with reduced size of membrane ruffles. A PprgH-gfp reporter revealed that relatively few of the 12023 population (and that of the equivalent strain ATCC 14028) express SPI-1 compared to other S. Typhimurium strains. Expression of a PhilA-gfp reporter mirrored that of PprgH-gfp in 12023 and SL1344, implicating reduced signalling via the transcription factor HilA in the heterogeneous SPI-1 expression of these strains. The previously unrecognized strain heterogeneity in SPI-1 expression and invasiveness has important implications for studies of Salmonella infection.
