RESUMEN
Neoantigen-based immunotherapy is an attractive potential treatment for previously intractable tumors. To effectively broaden the application of this approach, stringent biomarkers are crucial to identify responsive patients. ARID1A, a frequently mutated subunit of SWI/SNF chromatin remodeling complex, has been reported to determine tumor immunogenicity in some cohorts; however, mutations and deletions of ARID1A are not always linked to clinical responses to immunotherapy. In this study, we investigated immunotherapeutic responses based on ARID1A status in targeted therapy-resistant cancers. Mouse and human BRAFV600E melanomas with or without ARID1A expression were transformed into resistant to vemurafenib, an FDA-approved specific BRAFV600E inhibitor. Anti-PD-1 antibody treatment enhanced antitumor immune responses in vemurafenib-resistant ARID1A-deficient tumors but not in ARID1A-intact tumors or vemurafenib-sensitive ARID1A-deficient tumors. Neoantigens derived from accumulated somatic mutations during vemurafenib resistance were highly expressed in ARID1A-deficient tumors and promoted tumor immunogenicity. Furthermore, the newly generated neoantigens could be utilized as immunotherapeutic targets by vaccines. Finally, targeted therapy resistance-specific neoantigen in experimental human melanoma cells lacking ARID1A were validated to elicit T-cell receptor responses. Collectively, the classification of ARID1A-mutated tumors based on vemurafenib resistance as an additional indicator of immunotherapy response will enable a more accurate prediction to guide cancer treatment. Furthermore, the neoantigens that emerge with therapy resistance can be promising therapeutic targets for refractory tumors. Significance: Chemotherapy resistance promotes the acquisition of immunogenic neoantigens in ARID1A-deficient tumors that confer sensitivity to immune checkpoint blockade and can be utilized for developing antitumor vaccines, providing strategies to improve immunotherapy efficacy.
Asunto(s)
Antígenos de Neoplasias , Proteínas de Unión al ADN , Resistencia a Antineoplásicos , Melanoma , Factores de Transcripción , Vemurafenib , Animales , Humanos , Factores de Transcripción/genética , Factores de Transcripción/inmunología , Ratones , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/inmunología , Resistencia a Antineoplásicos/inmunología , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/genética , Vemurafenib/farmacología , Vemurafenib/uso terapéutico , Melanoma/inmunología , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/terapia , Inmunoterapia/métodos , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/inmunología , Línea Celular Tumoral , Femenino , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Mutación , Terapia Molecular Dirigida/métodos , Ratones Endogámicos C57BLRESUMEN
After activation, some invariant natural killer T (iNKT) cells are differentiated into Klrg1+ long-lived effector NKT1 cells. However, the regulation from the effector phase to the memory phase has not been elucidated. Zeb2 is a zinc finger E homeobox-binding transcription factor and is expressed in a variety of immune cells, but its function in iNKT cell differentiation remains also unknown. Here, we show that Zeb2 is dispensable for development of iNKT cells in the thymus and their maintenance in steady state peripheral tissues. After ligand stimulation, Zeb2 plays essential roles in the differentiation to and maintenance of Klrg1+ Cx3cr1+GzmA+ iNKT cell population derived from the NKT1 subset. Our results including single-cell-RNA-seq analysis indicate that Zeb2 regulates Klrg1+ long-lived iNKT cell differentiation by preventing apoptosis. Collectively, this study reveals the crucial transcriptional regulation by Zeb2 in establishment of the memory iNKT phase through driving differentiation of Klrg1+ Cx3cr1+GzmA+ iNKT population.
Asunto(s)
Células T Asesinas Naturales , Diferenciación Celular , Regulación de la Expresión Génica , Factores de Transcripción , TimoRESUMEN
Multiple myeloma (MM) remains an incurable hematological neoplasm. Neoantigen-specific T cell receptor (TCR)-engineered T (TCR-T) cell therapy is a potential alternative treatment. Particularly, TCRs derived from a third-party donor may cover broad ranges of neoantigens, whereas TCRs in patients suffering from immune disorders are limited. However, the efficacy and feasibility of treating MM have not been evaluated thoroughly. In this study, we established a system for identifying immunogenic mutant antigens on MM cells and their corresponding TCRs using healthy donor-derived peripheral blood mononuclear cells (PBMCs). Initially, the immune responses to 35 candidate peptides predicted by the immunogenomic analysis were investigated. Peptide-reactive T lymphocytes were enriched, and subsequently, TCR repertoires were determined by single-cell TCR sequencing. Eleven reconstituted TCRs showed mutation-specific responses against 4 peptides. Particularly, we verified the HLA-A∗24:02-binding QYSPVQATF peptide derived from COASY S55Y as the naturally processed epitope across MM cells, making it a promising immune target. Corresponding TCRs specifically recognized COASY S55Y+HLA-A∗24:02+ MM cells and augmented tumoricidal activity. Finally, adoptive cell transfer of TCR-T cells showed objective responses in the xenograft model. We initiatively proposed the utility of tumor mutated antigen-specific TCR genes to suppress MM. Our unique strategy will facilitate further identification of neoantigen-specific TCRs.
RESUMEN
Bovine respiratory syncytial virus (BRSV) strains that were detected in Kagoshima prefecture and isolated in Hokkaido between 2017 and 2019, together with a BRSV vaccine strain, were subjected to full-genome sequencing. The BRSV strains identified in Japan were found to be genetically close to each other but distant from the vaccine strains. The deduced amino acids at positions 206 and 208 of the glycoprotein (G protein), which form one of the major epitopes of the recent Japanese BRSV strains, were different from those of the vaccine strains. Therefore, the recent Japanese BRSV strains might be antigenically different from the BRSV vaccine strains.
Asunto(s)
Enfermedades de los Bovinos , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Bovino , Animales , Bovinos , Virus Sincitial Respiratorio Bovino/genética , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/veterinaria , Infecciones por Virus Sincitial Respiratorio/genética , Japón , Secuencia de Bases , Anticuerpos AntiviralesRESUMEN
SARS-CoV-2-specific CD8+ T cells are scarce but detectable in unexposed healthy donors (UHDs). It remains unclear whether pre-existing human coronavirus (HCoV)-specific CD8+ T cells are converted to functionally competent T cells cross-reactive to SARS-CoV-2. Here, we identified the HLA-A24-high binding, immunodominant epitopes in SARS-CoV-2 spike region that can be recognized by seasonal coronavirus-specific CD8+ T cells from HLA-A24+ UHDs. Cross-reactive CD8+ T cells were clearly reduced in patients with hematological malignancy, who are usually immunosuppressed, compared to those in UHDs. Furthermore, we showed that CD8+ T cells in response to a selected dominant epitope display multifunctionality and cross-functionality across HCoVs in HLA-A24+ donors. Cross-reactivity of T-cell receptors isolated from them exhibited selective diversity at the single-cell level. Taken together, when stimulated well by immunodominant epitopes, selective pre-existing CD8+ T cells with high functional avidity may be cross-reactive against SARS-CoV-2.
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Antígenos Virales/inmunología , Epítopos Inmunodominantes/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , SARS-CoV-2/inmunología , Linfocitos T Citotóxicos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , Reacciones Cruzadas , HumanosRESUMEN
Eomes regulates the differentiation of CD8+ T cells into effector and memory phases. However, its role in invariant (i)NKT cells remains unknown. Here, we show the impact of Eomes on iNKT cells in the thymus and peripheral tissue using conditional knockout (Eomes-cKO) mice. In the thymus, CD1d-tetramer+CD24+CD44-NK1.1-CD69+stage 0 iNKT cells express higher levels of Eomes than the other iNKT stages. We also found that Eomes regulates NKT1 cell differentiation predominantly. Interestingly, the expression of Eomes in the steady state is low, but can be upregulated after TCR stimulation. We also showed epigenetic changes in the Eomes locus after activation. In addition, vaccination of C57BL/6, but not Eomes-cKO mice with iNKT ligand-loaded dendritic cells generated KLRG1+iNKT cells in lung, characterized as effector memory phenotype by transcriptome profiling. Thus, Eomes regulates not only the differentiation of NKT1 cells in the thymus, but also their differentiation into memory-like KLRG1+iNKT cells in the periphery.
Asunto(s)
Regulación de la Expresión Génica/inmunología , Memoria Inmunológica/genética , Células T Asesinas Naturales/citología , Proteínas de Dominio T Box/genética , Transcriptoma/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular , Linaje de la Célula/genética , Linaje de la Célula/inmunología , Proliferación Celular , Células Dendríticas/citología , Células Dendríticas/inmunología , Perfilación de la Expresión Génica , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Pulmón/citología , Pulmón/inmunología , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células T Asesinas Naturales/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Transducción de Señal , Proteínas de Dominio T Box/deficiencia , Proteínas de Dominio T Box/inmunología , Timo/citología , Timo/inmunologíaRESUMEN
The recurrent translocation t(1;3)(p36;q21) is associated with myelodysplastic syndrome (MDS)/acute myelogenous leukemia (AML) characterized by trilineage dysplasia, especially dysmegakaryopoiesis and a poor prognosis. Recently, the two genes involved in this translocation have been identified: the MEL1 gene at 1p36.3, and the RPN1 gene at 3q21. The breakpoint in RPN1 is centromeric to the breakpoint cluster region of the inv(3) abnormality. Because the MEL1 transcript is detected only in leukemic cells with t(1;3)(p36;q21), ectopic expression of MEL1 driven by RPN1 at 3q21 is thought to contribute to the pathogenesis of t(1;3)(p36;q21) leukemia. However, the precise breakpoint in the patients has not yet been identified. With fluorescence in situ hybridization analysis by use of BAC/PAC probes, we identified the breakpoint at 1p36.3 in three MDS/AML patients with t(1;3)(p36;q21): within the first intron of the MEL1 gene (one patient) or within a 29-kb region located in the 5' region of MEL1 (two other patients). We detected several sizes of MEL1 transcript in two patients including the first patient, although we have not yet clarified whether MEL1 transcripts were different among the patients and whether a truncated MEL1 transcript was expressed in the first patient. This patient showed an unusual clinical profile, repeating progression to overt leukemia and conversion to MDS three times during the 29-month survival period, which might be related to a different molecular mechanism in this patient.
Asunto(s)
Región de Flanqueo 5'/genética , Proteínas Portadoras/genética , Rotura Cromosómica/genética , Cromosomas Humanos Par 1/genética , Proteínas de Unión al ADN , Intrones/genética , Leucemia Mielomonocítica Aguda/genética , Síndromes Mielodisplásicos/genética , Factores de Transcripción , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The t(3;12)(q26;p13) translocation is a recurrent chromosomal aberration observed in myeloid malignancies. It has been shown that the translocation results in the fusion of the TEL (ETV6) gene at 12p13 and the EV11 gene at 3q26. We report the first case with Philadelphia (Ph)-positive chronic myelogenous leukemia (CML) expressing the TEL/EVI1 fusion transcript. A 26-year-old man was initially diagnosed as having the chronic phase of Ph-positive CML. The t(3;12)(q26;p13) emerged 16 months prior to the myeloid blastic crisis. Reverse transcriptase-polymerase chain reaction detected the TEL/EVI1 transcript without the intervening 5' non-coding exon of EVI1, suggesting that inappropriate expression of the EVI1 protein driven by the TEL promotor could play a critical role in progression to the blast crisis of CML.
Asunto(s)
Cromosomas Humanos Par 12 , Cromosomas Humanos Par 3 , Proteínas de Unión al ADN/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas de Fusión Oncogénica/genética , Proto-Oncogenes , Proteínas Represoras/genética , Factores de Transcripción , Adulto , Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Proteína del Locus del Complejo MDS1 y EV11 , Masculino , Proteínas Proto-Oncogénicas c-ets , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Translocación Genética , Proteína ETS de Variante de Translocación 6RESUMEN
A cDNA encoding a novel serine protease, which we designated spinesin, has been cloned from human spinal cord. The longest open reading frame was 457 amino acids. A homology search revealed that the human spinesin gene was located at chromosome 11q23 and contained 13 exons, the gene structure being similar to that of TMPRSS3 whose gene is also located on 11q23. Spinesin has a simple type II transmembrane structure, consisting of, from the N terminus, a short cytoplasmic domain, a transmembrane domain, a stem region containing a scavenger receptor-like domain, and a serine protease domain. Unlike TMPRSS3, it carries no low density lipoprotein receptor domain in the stem region. The extracellular region carries five N-glycosylation sites. The sequence of the protease domain carried the essential triad His, Asp, and Ser and showed some similarity to that of TMPRSS2, hepsin, HAT, MT-SP1, TMPRSS3, and corin, sharing 45.5, 41.9, 41.3, 40.3, 39.1, and 38.5% identity, respectively. The putative mature protease domain preceded by H(6)DDDDK was produced in Escherichia coli, purified, and successfully activated by immobilized enterokinase. Its optimal pH was about 10. It cleaved synthetic substrates for trypsin, which is inhibited by p-amidinophenylmethanesulfonyl fluoride hydrochloride but not by antipain or leupeptin. Northern blot analysis against mRNA from human tissues including liver, lung, placenta, and heart demonstrated a specific expression of spinesin mRNA in the brain. Immunohistochemically, spinesin was predominantly expressed in neurons, in their axons, and at the synapses of motoneurons in the spinal cord. In addition, some oligodendrocytes were clearly stained. These results indicate that spinesin is transported to the synapses through the axons after its synthesis in the cytoplasm and may play important roles at the synapses. Further analyses are required to clarify its roles at the synapses and in oligodendrocytes.