RESUMO
Natural Killer T cells (NKT cells) are emerging as critical regulators of pro- and anti-tumor immunity, both at baseline and in therapeutic settings. While type I NKT cells can promote anti-tumor immunity, their activity in the tumor microenvironment may be limited by negative regulators such as inhibitory immune checkpoints. We observed dominant expression of B- and T-lymphocyte attenuator (BTLA) on type I NKT cells in polyoma middle T oncogene-driven (PyMT) murine autochthonous mammary tumors. Other immune checkpoint receptors, such as programmed cell death 1 (PD-1) were equally distributed among T cell populations. Interference with BTLA using neutralizing antibodies limited tumor growth and pulmonary metastasis in the PyMT model in a therapeutic setting, correlating with an increase in type I NKT cells and expression of cytotoxic marker genes. While therapeutic application of an anti-PD-1 antibody increased the number of CD8+ cytotoxic T cells and elevated IL-12 expression, tumor control was not established. Expression of ZBTB16, the lineage-determining transcription factor of type I NKT cells, was correlated with a favorable patient prognosis in the METABRIC dataset, and BTLA levels were instrumental to further distinguish prognosis in patents with high ZBTB16 expression. Taken together, these data support a role of BTLA on type I NKT cells in limiting anti-tumor immunity.
Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Receptores Imunológicos/genética , Animais , Biomarcadores , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Imunofenotipagem , Contagem de Linfócitos , Camundongos , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteína com Dedos de Zinco da Leucemia Promielocítica/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo , Receptores Imunológicos/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Haemophilus parasuis is the causative agent of Glässer's disease, which is responsible for considerable economic losses in the pig-rearing industry. The aim of the study reported here was the identification, sequencing and molecular characterization of the TonB region that includes tonB, exbBD, and tbpBA genes in H. parasuis. In addition, two fusion proteins were generated. One of them (pGEX-6P-1-GST-TbpB) contained the first 501 amino acids of H. parasuis TbpB protein, while the second (pBAD-Thio-TbpB-V5-His) included the first 102 amino acids of H. parasuis TbpB N-terminus domain. A panel of 14 hybridomas secreting monoclonal antibodies was raised against the two recombinant TbpB fusion proteins. Furthermore, to assess whether the expression of the H. parasuis ExbB, TbpB, and TbpA proteins was upregulated under conditions of restricted availability of iron, a rabbit polyclonal antibody against H. parasuis TbpB-His fusion protein was produced. A rabbit polyclonal antibody against serotype 7 of Actinobacillus pleuropneumoniae ExbB and TbpA proteins was also used for the detection of the homologous proteins in H. parasuis. Overall, the data indicate that H. parasuis, like other members of the Pasteurellaceae family, possesses the genetic elements of the TonB region for iron acquisition and the transferrin-binding proteins encoded under this region are upregulated under restricted iron availability.
