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1.
Cancer Res ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635899

RESUMEN

T cell exhaustion is a major contributor to immunosuppression in the tumor microenvironment (TME). Blockade of key regulators of T cell exhaustion, such as PD-1, can reinvigorate tumor-specific T cells and activate anti-tumor immunity in various types of cancer. Here, we identified that CD106 was specifically expressed in exhausted CD8+ T cells in the TME using single-cell RNA-sequencing. High CD106 expression in the TME in clinical samples corresponded to improved response to cancer immunotherapy. CD106 in tumor-specific T cells suppressed anti-tumor immunity both in vitro and in vivo, and loss of CD106 in CD8+ T cells suppressed tumor growth and improved response to PD-1 blockade. Mechanistically, CD106 inhibited T-cell receptor (TCR) signaling by interacting with the TCR/CD3 complex and reducing its surface expression. Together, these findings provide insights into the immunosuppressive role of CD106 expressed in tumor-specific exhausted CD8+ T cells, identifying it as a potential biomarker and therapeutic target for cancer immunotherapy.

2.
JCI Insight ; 9(3)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329122

RESUMEN

Immune checkpoint inhibitors (ICIs) are indicated for a diverse range of cancer types, and characterizing the tumor immune microenvironment is critical for optimizing therapeutic strategies, including ICIs. T cell infiltration and activation status in the tumor microenvironment greatly affects the efficacy of ICIs. Here, we show that semaphorin 6D (Sema6D) forward signaling, which is reportedly involved in coordinating the orientation of cell development and migration as a guidance factor, impaired the infiltration and activation of tumor-specific CD8+ T cells in murine oral tumors. Sema6D expressed by nonhematopoietic cells was responsible for this phenotype. Plexin-A4, a receptor for Sema6D, inhibited T cell infiltration and partially suppressed CD8+ T cell activation and proliferation induced by Sema6D stimulation. Moreover, mouse oral tumors, which are resistant to PD-1-blocking treatment in wild-type mice, showed a response to the treatment in Sema6d-KO mice. Finally, analyses of public data sets of human head and neck squamous cell carcinoma, pan-cancer cohorts, and a retrospective cohort study showed that SEMA6D was mainly expressed by nonhematopoietic cells such as cancer cells, and SEMA6D expression was significantly negatively correlated with CD8A, PDCD1, IFNG, and GZMB expression. Thus, targeting Sema6D forward signaling is a promising option for increasing ICI efficacy.


Asunto(s)
Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Animales , Humanos , Ratones , Proliferación Celular , Neoplasias de Cabeza y Cuello/genética , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Microambiente Tumoral
3.
Cell Rep ; 43(2): 113797, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38363680

RESUMEN

Immune checkpoint inhibitors exert clinical efficacy against various types of cancer through reinvigoration of exhausted CD8+ T cells that attack cancer cells directly in the tumor microenvironment (TME). Using single-cell sequencing and mouse models, we show that CXCL13, highly expressed in tumor-infiltrating exhausted CD8+ T cells, induces CD4+ follicular helper T (TFH) cell infiltration, contributing to anti-tumor immunity. Furthermore, a part of the TFH cells in the TME exhibits cytotoxicity and directly attacks major histocompatibility complex-II-expressing tumors. TFH-like cytotoxic CD4+ T cells have high LAG-3/BLIMP1 and low TCF1 expression without self-renewal ability, whereas non-cytotoxic TFH cells express low LAG-3/BLIMP1 and high TCF1 with self-renewal ability, closely resembling the relationship between terminally differentiated and stem-like progenitor exhaustion in CD8+ T cells, respectively. Our findings provide deep insights into TFH-like CD4+ T cell exhaustion with helper progenitor and cytotoxic differentiated functions, mediating anti-tumor immunity orchestrally with CD8+ T cells.


Asunto(s)
Agotamiento de Células T , Microambiente Tumoral , Animales , Ratones , Linfocitos T CD8-positivos , Diferenciación Celular , Linfocitos T CD4-Positivos
4.
Microbiol Spectr ; 11(4): e0214323, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37428088

RESUMEN

T cell immunity is crucial for long-term immunological memory, but the profile of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific memory T cells in individuals who recovered from COVID-19 (COVID-19-convalescent individuals) is not sufficiently assessed. In this study, the breadth and magnitude of SARS-CoV-2-specific T cell responses were determined in COVID-19-convalescent individuals in Japan. Memory T cells against SARS-CoV-2 were detected in all convalescent individuals, and those with more severe disease exhibited a broader T cell response relative to cases with mild symptoms. Comprehensive screening of T cell responses at the peptide level was conducted for spike (S) and nucleocapsid (N) proteins, and regions frequently targeted by T cells were identified. Multiple regions in S and N proteins were targeted by memory T cells, with median numbers of target regions of 13 and 4, respectively. A maximum of 47 regions were recognized by memory T cells for an individual. These data indicate that SARS-CoV-2-convalescent individuals maintain a substantial breadth of memory T cells for at least several months following infection. Broader SARS-CoV-2-specific CD4+ T cell responses, relative to CD8+ T cell responses, were observed for the S but not the N protein, suggesting that antigen presentation is different between viral proteins. The binding affinity of predicted CD8+ T cell epitopes to HLA class I molecules in these regions was preserved for the Delta variant and at 94 to 96% for SARS-CoV-2 Omicron subvariants, suggesting that the amino acid changes in these variants do not have a major impact on antigen presentation to SARS-CoV-2-specific CD8+ T cells. IMPORTANCE RNA viruses, including SARS-CoV-2, evade host immune responses through mutations. As broader T cell responses against multiple viral proteins could minimize the impact of each single amino acid mutation, the breadth of memory T cells would be one essential parameter for effective protection. In this study, breadth of memory T cells to S and N proteins was assessed in COVID-19-convalescent individuals. While broad T cell responses were induced against both proteins, the ratio of N to S proteins for breadth of T cell responses was significantly higher in milder cases. The breadth of CD4+ and CD8+ T cell responses was also significantly different between S and N proteins, suggesting different contributions of N and S protein-specific T cells for COVID-19 control. Most CD8+ T cell epitopes in the immunodominant regions maintained their HLA binding to SARS-CoV-2 Omicron subvariants. Our study provides insights into understanding the protective efficacy of SARS-CoV-2-specific memory T cells against reinfection.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Linfocitos T CD8-positivos , Epítopos de Linfocito T , Proteínas Virales
5.
Sci Adv ; 9(24): eadf0661, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37315144

RESUMEN

Severe acute respiratory syndrome coronavirus 2-neutralizing antibodies primarily target the spike receptor binding domain (RBD). However, B cell antigen receptors (BCRs) on RBD-binding memory B (Bmem) cells have variation in the neutralizing activities. Here, by combining single Bmem cell profiling with antibody functional assessment, we dissected the phenotype of Bmem cell harboring the potently neutralizing antibodies in coronavirus disease 2019 (COVID-19)-convalescent individuals. The neutralizing subset was marked by an elevated CD62L expression and characterized by distinct epitope preference and usage of convergent VH (variable region of immunoglobulin heavy chain) genes, accounting for the neutralizing activities. Concordantly, the correlation was observed between neutralizing antibody titers in blood and CD62L+ subset, despite the equivalent RBD binding of CD62L+ and CD62L- subset. Furthermore, the kinetics of CD62L+ subset differed between the patients who recovered from different COVID-19 severities. Our Bmem cell profiling reveals the unique phenotype of Bmem cell subset that harbors potently neutralizing BCRs, advancing our understanding of humoral protection.


Asunto(s)
Subgrupos de Linfocitos B , COVID-19 , Selectina L , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , SARS-CoV-2
6.
Sci Adv ; 9(20): eade0718, 2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37205755

RESUMEN

Immune checkpoint inhibitors (ICIs) have caused revolutionary changes in cancer treatment, but low response rates remain a challenge. Semaphorin 4A (Sema4A) modulates the immune system through multiple mechanisms in mice, although the role of human Sema4A in the tumor microenvironment remains unclear. This study demonstrates that histologically Sema4A-positive non-small cell lung cancer (NSCLC) responded significantly better to anti-programmed cell death 1 (PD-1) antibody than Sema4A-negative NSCLC. Intriguingly, SEMA4A expression in human NSCLC was mainly derived from tumor cells and was associated with T cell activation. Sema4A promoted cytotoxicity and proliferation of tumor-specific CD8+ T cells without terminal exhaustion by enhancing mammalian target of rapamycin complex 1 and polyamine synthesis, which led to improved efficacy of PD-1 inhibitors in murine models. Improved T cell activation by recombinant Sema4A was also confirmed using isolated tumor-infiltrating T cells from patients with cancer. Thus, Sema4A might be a promising therapeutic target and biomarker for predicting and promoting ICI efficacy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Semaforinas , Animales , Humanos , Ratones , Anticuerpos Bloqueadores , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Linfocitos T CD8-positivos , Proliferación Celular , Neoplasias Pulmonares/tratamiento farmacológico , Receptor de Muerte Celular Programada 1 , Semaforinas/genética , Semaforinas/metabolismo , Microambiente Tumoral
7.
J Exp Med ; 220(2)2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36512034

RESUMEN

In contrast to a second dose of the SARS-CoV-2 mRNA vaccine, a third dose elicits potent neutralizing activity against the Omicron variant. To address the underlying mechanism for this differential antibody response, we examined spike receptor-binding domain (RBD)-specific memory B cells in vaccinated individuals. Frequency of Omicron-reactive memory B cells increased ∼9 mo after the second vaccine dose. These memory B cells show an altered distribution of epitopes from pre-second memory B cells, presumably due to an antibody feedback mechanism. This hypothesis was tested using mouse models, showing that an addition or a depletion of RBD-induced serum antibodies results in a concomitant increase or decrease, respectively, of Omicron-reactive germinal center (GC) and memory B cells. Our data suggest that pre-generated antibodies modulate the selection of GC and subsequent memory B cells after the second vaccine dose, accumulating more Omicron-reactive memory B cells over time, which contributes to the generation of Omicron-neutralizing antibodies elicited by the third vaccine dose.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Animales , Ratones , Humanos , Retroalimentación , Células B de Memoria , SARS-CoV-2 , COVID-19/prevención & control , ARN Mensajero , Anticuerpos Neutralizantes , Anticuerpos Antivirales
8.
Plant Pathol J ; 38(4): 383-394, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35953058

RESUMEN

In Japan, the P1 protein (S-type) encoded by leek yellow stripe virus (LYSV) isolates detected in Honshu and southward is shorter than the P1 (N-type) of LYSV isolates from garlic grown in Hokkaido due to a large deletion in the N-terminal half. In garlic fields in Hokkaido, two types of LYSV isolate with N- and S-type P1s are sometimes found in mixed infections. In this study, we confirmed that N- and S-type P1 sequences were present in the same plant and that they belong to different evolutionary phylogenetic groups. To investigate how LYSV with S-type P1 (LYSV-S) could have invaded LYSV with N-type P1 (LYSV-N)-infected garlic, we examined wild Allium spp. plants in Hokkaido and found that LYSV was almost undetectable. On the other hand, in Honshu, LYSV-S was detected at a high frequency in Allium spp. other than garlic, suggesting that the LYSV-S can infect a wider host range of Allium spp. compared to LYSV-N. Because P1 proteins of potyviruses have been reported to promote RNA silencing suppressor (RSS) activity of HC-Pro proteins, we analyzed whether the same was true for P1 of LYSV. In onion, contrary to expectation, the P1 protein itself had RSS activity. Moreover, the RSS activity of S-type P1 was considerably stronger than that of N-type P1, suggesting that LYSV P1 may be able to enhance its RSS activity when the deletion is in the N-terminal half and that acquiring S-type P1 may have enabled LYSV to expand its host range.

9.
Virus Evol ; 8(2): veac060, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903148

RESUMEN

Characterizing the detailed spatial and temporal dynamics of plant pathogens can provide valuable information for crop protection strategies. However, the epidemiological characteristics and evolutionary trajectories of pathogens can differ markedly from one country to another. The most widespread and important virus of brassica vegetables, turnip mosaic virus (TuMV), causes serious plant diseases in Japan. We collected 317 isolates of TuMV from Raphanus and Brassica plants throughout Japan over nearly five decades. Genomic sequences from these isolates were combined with published sequences. We identified a total of eighty-eight independent recombination events in Japanese TuMV genomes and found eighty-two recombination-type patterns in Japan. We assessed the evolution of TuMV through space and time using whole and partial genome sequences of both nonrecombinants and recombinants. Our results suggest that TuMV was introduced into Japan after the country emerged from its isolationist policy (1639-1854) in the Edo period and then dispersed to other parts of Japan in the 20th century. The results of our analyses reveal the complex structure of the TuMV population in Japan and emphasize the importance of identifying recombination events in the genome. Our study also provides an example of surveying the epidemiology of a virus that is highly recombinogenic.

10.
Cell Rep Med ; 3(5): 100631, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35545084

RESUMEN

Two doses of Pfizer/BioNTech BNT162b2 mRNA vaccine elicit robust severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies with frequent adverse events. Here, by applying a high-dimensional immune profiling on 92 vaccinees, we identify six vaccine-induced immune dynamics that correlate with the amounts of neutralizing antibodies, the severity of adverse events, or both. The early dynamics of natural killer (NK)/monocyte subsets (CD16+ NK cells, CD56high NK cells, and non-classical monocytes), dendritic cell (DC) subsets (DC3s and CD11c- Axl+ Siglec-6+ [AS]-DCs), and NKT-like cells are revealed as the distinct cell correlates for neutralizing-antibody titers, severity of adverse events, and both, respectively. The cell correlates for neutralizing antibodies or adverse events are consistently associated with elevation of interferon gamma (IFN-γ)-inducible chemokines, but the chemokine receptors CCR2 and CXCR3 are expressed in distinct manners between the two correlates: vaccine-induced expression on the neutralizing-antibody correlate and constitutive expression on the adverse-event correlate. The finding may guide vaccine strategies that balance immunogenicity and reactogenicity.


Asunto(s)
Vacuna BNT162 , COVID-19 , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacuna BNT162/efectos adversos , Vacuna BNT162/inmunología , Vacuna BNT162/uso terapéutico , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/uso terapéutico , Humanos , SARS-CoV-2/genética , Vacunas Sintéticas/efectos adversos , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/uso terapéutico , Vacunas de ARNm/efectos adversos , Vacunas de ARNm/inmunología , Vacunas de ARNm/uso terapéutico
11.
Cell Rep ; 38(5): 110331, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35108529

RESUMEN

PD-1 blockade exerts clinical efficacy against various types of cancer by reinvigorating T cells that directly attack tumor cells (tumor-specific T cells) in the tumor microenvironment (TME), and tumor-infiltrating lymphocytes (TILs) also comprise nonspecific bystander T cells. Here, using single-cell sequencing, we show that TILs include skewed T cell clonotypes, which are characterized by exhaustion (Tex) or nonexhaustion signatures (Tnon-ex). Among skewed clonotypes, those in the Tex, but not those in the Tnon-ex, cluster respond to autologous tumor cell lines. After PD-1 blockade, non-preexisting tumor-specific clonotypes in the Tex cluster appear in the TME. Tumor-draining lymph nodes (TDLNs) without metastasis harbor a considerable number of such clonotypes, whereas these clonotypes are rarely detected in peripheral blood. We propose that tumor-infiltrating skewed T cell clonotypes with an exhausted phenotype directly attack tumor cells and that PD-1 blockade can promote infiltration of such Tex clonotypes, mainly from TDLNs.


Asunto(s)
Linfocitos T CD8-positivos/efectos de los fármacos , Inhibidores de Puntos de Control Inmunológico/farmacología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Microambiente Tumoral/inmunología , Animales , Linfocitos T CD8-positivos/metabolismo , Línea Celular Tumoral/efectos de los fármacos , Humanos , Linfocitos Infiltrantes de Tumor/metabolismo , Ratones , Receptor de Muerte Celular Programada 1/metabolismo , Microambiente Tumoral/efectos de los fármacos
12.
Cancer Res Commun ; 2(7): 739-753, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-36923281

RESUMEN

Some patients experience mixed response to immunotherapy, whose biological mechanisms and clinical impact have been obscure. We obtained two tumor samples from lymph node (LN) metastatic lesions in a same patient. Whole exome sequencing for the both tumors and single-cell sequencing for the both tumor-infiltrating lymphocytes (TIL) demonstrated a significant difference in tumor clonality and TILs' characteristics, especially exhausted T-cell clonotypes, although a close relationship between the tumor cell and T-cell clones were observed as a response of an overlapped exhausted T-cell clone to an overlapped neoantigen. To mimic the clinical setting, we generated a mouse model of several clones from a same tumor cell line. Similarly, differential tumor clones harbored distinct TILs, and one responded to programmed cell death protein 1 (PD-1) blockade but the other did not in this model. We further conducted cohort study (n = 503) treated with PD-1 blockade monotherapies to investigate the outcome of mixed response. Patients with mixed responses to PD-1 blockade had a poor prognosis in our cohort. Particularly, there were significant differences in both tumor and T-cell clones between the primary and LN lesions in a patient who experienced tumor response to anti-PD-1 mAb followed by disease progression in only LN metastasis. Our results underscore that intertumoral heterogeneity alters characteristics of TILs even in the same patient, leading to mixed response to immunotherapy and significant difference in the outcome. Significance: Several patients experience mixed responses to immunotherapies, but the biological mechanisms and clinical significance remain unclear. Our results from clinical and mouse studies underscore that intertumoral heterogeneity alters characteristics of TILs even in the same patient, leading to mixed response to immunotherapy and significant difference in the outcome.


Asunto(s)
Neoplasias , Animales , Ratones , Estudios de Cohortes , Neoplasias/genética , Inmunoterapia/métodos , Linfocitos T , Linfocitos Infiltrantes de Tumor
13.
Gastroenterology ; 162(3): 799-812, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34687740

RESUMEN

BACKGROUND & AIMS: A detailed understanding of antitumor immunity is essential for optimal cancer immune therapy. Although defective mutations in the B2M and HLA-ABC genes, which encode molecules essential for antigen presentation, have been reported in several studies, the effects of these defects on tumor immunity have not been quantitatively evaluated. METHODS: Mutations in HLA-ABC genes were analyzed in 114 microsatellite instability-high colorectal cancers using a long-read sequencer. The data were further analyzed in combination with whole-exome sequencing, transcriptome sequencing, DNA methylation array, and immunohistochemistry data. RESULTS: We detected 101 truncating mutations in 57 tumors (50%) and loss of 61 alleles in 21 tumors (18%). Based on the integrated analysis that enabled the immunologic subclassification of microsatellite instability-high colorectal cancers, we identified a subtype of tumors in which lymphocyte infiltration was reduced, partly due to reduced expression of HLA-ABC genes in the absence of apparent genetic alterations. Survival time of patients with such tumors was shorter than in patients with other tumor types. Paradoxically, tumor mutation burden was highest in the subtype, suggesting that the immunogenic effect of accumulating mutations was counterbalanced by mutations that weakened immunoreactivity. Various genetic and epigenetic alterations, including frameshift mutations in RFX5 and promoter methylation of PSMB8 and HLA-A, converged on reduced expression of HLA-ABC genes. CONCLUSIONS: Our detailed immunogenomic analysis provides information that will facilitate the improvement and development of cancer immunotherapy.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Genes MHC Clase I/genética , Escape del Tumor/genética , Escape del Tumor/inmunología , Microglobulina beta-2/genética , Alelos , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Metilación de ADN , Epigénesis Genética , Expresión Génica , Antígenos HLA-A/genética , Antígenos HLA-A/metabolismo , Humanos , Inmunogenética , Linfocitos Infiltrantes de Tumor , Inestabilidad de Microsatélites , Complejo de la Endopetidasa Proteasomal/genética , Factores de Transcripción del Factor Regulador X/genética , Tasa de Supervivencia , Microglobulina beta-2/metabolismo
14.
J Exp Med ; 218(12)2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34647971

RESUMEN

Adaptive immunity is a fundamental component in controlling COVID-19. In this process, follicular helper T (Tfh) cells are a subset of CD4+ T cells that mediate the production of protective antibodies; however, the SARS-CoV-2 epitopes activating Tfh cells are not well characterized. Here, we identified and crystallized TCRs of public circulating Tfh (cTfh) clonotypes that are expanded in patients who have recovered from mild symptoms. These public clonotypes recognized the SARS-CoV-2 spike (S) epitopes conserved across emerging variants. The epitope of the most prevalent cTfh clonotype, S864-882, was presented by multiple HLAs and activated T cells in most healthy donors, suggesting that this S region is a universal T cell epitope useful for booster antigen. SARS-CoV-2-specific public cTfh clonotypes also cross-reacted with specific commensal bacteria. In this study, we identified conserved SARS-CoV-2 S epitopes that activate public cTfh clonotypes associated with mild symptoms.


Asunto(s)
COVID-19/inmunología , Epítopos de Linfocito T/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Adulto , Anticuerpos Antivirales/inmunología , Femenino , Antígenos HLA/inmunología , Humanos , Activación de Linfocitos , Masculino
15.
J Exp Med ; 218(12)2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34623376

RESUMEN

Broadly protective vaccines against SARS-related coronaviruses that may cause future outbreaks are urgently needed. The SARS-CoV-2 spike receptor-binding domain (RBD) comprises two regions, the core-RBD and the receptor-binding motif (RBM); the former is structurally conserved between SARS-CoV-2 and SARS-CoV. Here, in order to elicit humoral responses to the more conserved core-RBD, we introduced N-linked glycans onto RBM surfaces of the SARS-CoV-2 RBD and used them as immunogens in a mouse model. We found that glycan addition elicited higher proportions of the core-RBD-specific germinal center (GC) B cells and antibody responses, thereby manifesting significant neutralizing activity for SARS-CoV, SARS-CoV-2, and the bat WIV1-CoV. These results have implications for the design of SARS-like virus vaccines.


Asunto(s)
Anticuerpos Antivirales/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , COVID-19/inmunología , Polisacáridos/inmunología , SARS-CoV-2/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Secuencias de Aminoácidos , Animales , COVID-19/genética , COVID-19/prevención & control , Vacunas contra la COVID-19/genética , Vacunas contra la COVID-19/inmunología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Polisacáridos/genética , Dominios Proteicos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
16.
J Exp Med ; 218(1)2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33045065

RESUMEN

A still unanswered question is what drives the small fraction of activated germinal center (GC) B cells to become long-lived quiescent memory B cells. We found here that a small population of GC-derived CD38intBcl6hi/intEfnb1+ cells with lower mTORC1 activity favored the memory B cell fate. Constitutively high mTORC1 activity led to defects in formation of the CD38intBcl6hi/intEfnb1+ cells; conversely, decreasing mTORC1 activity resulted in relative enrichment of this memory-prone population over the recycling-prone one. Furthermore, the CD38intBcl6hi/intEfnb1+ cells had higher levels of Bcl2 and surface BCR that, in turn, contributed to their survival and development. We also found that downregulation of Bcl6 resulted in increased expression of both Bcl2 and BCR. Given the positive correlation between the strength of T cell help and mTORC1 activity, our data suggest a model in which weak help from T cells together with provision of an increased survival signal are key for GC B cells to adopt a memory B cell fate.


Asunto(s)
Linfocitos B/inmunología , Reprogramación Celular/inmunología , Centro Germinal/inmunología , Memoria Inmunológica , Transducción de Señal/inmunología , Animales , Antígenos de Diferenciación/genética , Antígenos de Diferenciación/inmunología , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Reprogramación Celular/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/inmunología , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/inmunología , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Transducción de Señal/genética , Linfocitos T Colaboradores-Inductores/inmunología
17.
Surg Radiol Anat ; 43(2): 243-250, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32960308

RESUMEN

PURPOSE: Fibers of the glossopharyngeal part of the superior constrictor muscle are connected with fibers of the transverse lingual muscle, forming a ring of muscle at the base of the tongue. This group of muscles constrict the midpharyngeal cavity during retrusive movement of the tongue. The purpose of this study is to identify the contribution of the lingual branch of the glossopharyngeal nerve to the neuro-motor control of three muscles: the glossopharyngeal part of the superior pharyngeal constrictor muscle, the palatopharyngeal and the palatoglossus muscles. METHODS: Six en bloc samples (9 sides), including the tissue from the skull base to the hyoid bone were obtained from adult human cadavers. Nerve fiber of the lingual branch of the glossopharyngeal nerve (main root of the glossopharyngeal nerve) was examined by the use of a binocular stereomicroscope. RESULTS: We observed that, after branching to the stylopharyngeal muscle, the lingual branch of the glossopharyngeal nerve branched to the glossopharyngeal part of the superior pharyngeal constrictor muscle, the palatopharyngeal and the palatoglossus muscles before inserting into the space between the muscle layers of the superior and middle pharyngeal constrictors. CONCLUSION: These neuromuscular arrangements may suggest the presence of specialized constrictive movements of the midpharygeal cavity at the level of the base of the tongue with the retrusive movement of the tongue. The simultaneous contraction of the palatopharyngeal and palatoglossus muscles on the pharyngeal stage of deglutition may aid in the passage of bolus from the oral cavity to the midpharyngeal cavity by increasing pharyngeal pressure.


Asunto(s)
Nervio Glosofaríngeo/anatomía & histología , Fibras Nerviosas , Músculos Faríngeos/inervación , Lengua/inervación , Adulto , Deglución/fisiología , Humanos , Contracción Muscular/fisiología , Músculos Faríngeos/fisiología , Lengua/fisiología
18.
Artículo en Inglés | MEDLINE | ID: mdl-31165049

RESUMEN

APOBEC3G (A3G) is a cellular protein that inhibits HIV-1 infection through virion incorporation. The interaction of the A3G N-terminal domain (NTD) with RNA is essential for A3G incorporation in the HIV-1 virion. The interaction between A3G-NTD and RNA is not completely understood. The A3G-NTD is also recognized by HIV-1 Viral infectivity factor (Vif) and A3G-Vif binding leads to A3G degradation. Therefore, the A3G-Vif interaction is a target for the development of antiviral therapies that block HIV-1 replication. However, targeting the A3G-Vif interactions could disrupt the A3G-RNA interactions that are required for A3G's antiviral activity. To better understand A3G-RNA binding, we generated in silico docking models to simulate the RNA-binding propensity of A3G-NTD. We simulated the A3G-NTD residues with high RNA-binding propensity, experimentally validated our prediction by testing A3G-NTD mutations, and identified structural determinants of A3G-RNA binding. In addition, we found a novel amino acid residue, I26 responsible for RNA interaction. The new structural insights provided here will facilitate the design of pharmaceuticals that inhibit A3G-Vif interactions without negatively impacting A3G-RNA interactions.


Asunto(s)
Desaminasa APOBEC-3G/química , Desaminasa APOBEC-3G/metabolismo , VIH-1/inmunología , ARN Viral/metabolismo , Desaminasa APOBEC-3G/genética , Análisis Mutacional de ADN , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Simulación del Acoplamiento Molecular , Unión Proteica
19.
J Allergy Clin Immunol ; 143(3): 1163-1175.e15, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30053529

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyposis (CRSwNP) is characterized by eosinophilic inflammation and polyposis at the nose and paranasal sinus and a high concentration of IgE in nasal polyps (NPs). The causative antigen and pathogenesis of CRSwNP remain unknown. OBJECTIVE: We aimed to identify reactive allergens of IgE antibodies produced locally in NPs of patients with CRSwNP. We also attempted to unravel the differentiation pathway of IgE-producing B cells in NPs. METHODS: IgE reactivity of patients with CRSwNP was investigated by characterizing single cell-derived mAbs. T-cell response against identified allergens was investigated in vitro. NP-infiltrating lymphocytes were characterized by using flow cytometry. Immunoglobulins expressed in NPs were analyzed by using high-throughput DNA sequencing for immunoglobulin. RESULTS: About 20% of isolated IgE antibodies derived from NP-residing plasmablasts specifically recognized surface determinants of nasal bacteria, such as Staphylococcus aureus, Streptococcus pyogenes, and Haemophilus influenzae. A TH2 response against S pyogenes was observed in patients with CRSwNP. Flow cytometric analysis revealed sizable germinal center B-like cell and plasmablast subsets expressing IgE on the cell surface in NPs. High-throughput DNA sequencing immunoglobulin analysis highlighted the clonal connectivity of IgE with IgG and IgA1. The Iε-Cα1 circle transcript was detected in NPs. CONCLUSIONS: In patients with CRSwNP, nasal bacteria-reactive B cells differentiate into IgE-producing B cells through IgG/IgA1-IgE class switching, suggesting that allergic conversion of the mucosal response against nasal bacteria underlies disease pathogenesis.


Asunto(s)
Linfocitos B/inmunología , Bacterias/inmunología , Inmunidad Mucosa , Inmunoglobulina E/inmunología , Pólipos Nasales/inmunología , Rinitis/inmunología , Sinusitis/inmunología , Adulto , Anciano , Anticuerpos Monoclonales/farmacología , Células Cultivadas , Enfermedad Crónica , Eosinofilia/inmunología , Eosinofilia/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/inmunología , Mucosa Nasal/microbiología , Pólipos Nasales/microbiología , Rinitis/microbiología , Sinusitis/microbiología , Adulto Joven
20.
J Environ Manage ; 231: 749-756, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30408768

RESUMEN

Crushed stone powder and aluminum ash are industrial wastes, and effective utilization of these wastes has been highly expected. Since the main components of the two wastes are Si, Al and O, those wastes can be used as starting materials for synthesis of zeolites of which some types have been commercialized as catalysts and ion-exchangers. In this study, zeolites A and X well-known as practical materials were successfully synthesized with high purity using the two industrial wastes by a mild process based on two hydrothermal treatments with intermediate acid treatment. In the first hydrothermal treatment at 150 °C, quartz in the crushed stone powder was dissolved and acid-soluble hydroxysodalite (Na8(AlSiO4)6(H2O)2(OH)2) with Si/Al = 1 and sodium aluminosilicate (Na6(AlSiO4)6) were formed. Those compounds were dissolved with HCl aq. solution. The zeolites were successfully synthesized from the second hydrothermal treatment of the yellow dried filtrates at 80 °C in NaOH aq. solution. In the process proposed, removal of Ca from the crushed stone powder was effective to formation of zeolites A and/or X. Selective synthesis of zeolites A and X was achieved by controlling the acid treatment conditions. Furthermore, the effect of the drying condition of the filtrate obtained after the acid treatment was also investigated on the differences in the product phase.


Asunto(s)
Zeolitas , Aluminio , Catálisis , Ceniza del Carbón , Residuos Industriales
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