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1.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526692

RESUMEN

A hallmark of cancer, including pancreatic ductal adenocarcinoma (PDA), is a massive stromal and inflammatory reaction. Many efforts have been made to identify the anti- or protumoral role of cytokines and immune subpopulations within the stroma. Here, we investigated the role of interleukin-17A (IL17A) and its effect on tumor fibroblasts and the tumor microenvironment. We used a spontaneous PDA mouse model (KPC) crossed to IL17A knockout mice to show an extensive desmoplastic reaction, without impaired immune infiltration. Macrophages, especially CD80+ and T cells, were more abundant at the earlier time point. In T cells, a decrease in FoxP3+ cells and an increase in CD8+ T cells were observed in KPC/IL17A-/- mice. Fibroblasts isolated from IL17A+/+ and IL17A-/- KPC mice revealed very different messenger RNA (mRNA) and protein profiles. IL17A-/- fibroblasts displayed the ability to restrain tumor cell invasion by producing factors involved in extracellular matrix remodeling, increasing T cell recruitment, and producing higher levels of cytokines and chemokines favoring T helper 1 cell recruitment and activation and lower levels of those recruiting myeloid/granulocytic immune cells. Single-cell quantitative PCR on isolated fibroblasts confirmed a very divergent profile of IL17A-proficient and -deficient cells. All these features can be ascribed to increased levels of IL17F observed in the sera of IL17A-/- mice, and to the higher expression of its cognate receptor (IL17RC) specifically in IL17A-/- cancer-associated fibroblasts (CAFs). In addition to the known effects on neoplastic cell transformation, the IL17 cytokine family uniquely affects fibroblasts, representing a suitable candidate target for combinatorial immune-based therapies in PDA.


Asunto(s)
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Interleucina-17/genética , Receptores de Interleucina/genética , Adenocarcinoma/patología , Animales , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Carcinogénesis/genética , Carcinoma Ductal Pancreático/patología , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/genética , Humanos , Ratones , Ratones Noqueados , Microambiente Tumoral/genética
2.
Cytokine ; 161: 156061, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36252436

RESUMEN

The loss of control of cell proliferation, apoptosis regulation and contact inhibition leads to tumor development. While benign tumors are restricted to their primary space, i.e. where these tumors first originate, the metastatic tumors not only disseminate- facilitated by hypoxia-driven neovascularization- to distant secondary sites but also show substantial changes in metabolism, tissue architectures, gene expression profiles and immune phenotypes. All these alterations result in radio-, chemo- and immune-resistance rendering these metastatic tumor cells refractory to therapy. Since the beginning of the transformation, these factors- which influence each other- are incorporated to the developing and metastasizing tumor. As a result, the complexities in the heterogeneity of tumor progressively increase. This space-time function in the heterogeneity of tumors is generated by various conditions and factors at the genetic as well as microenvironmental levels, for example, endogenous retroviruses, methylation and epigenetic dysregulation that may be etiology-specific, cancer associated inflammation, remodeling of the extracellular matrix and mesenchymal cell shifted functions. On the one hand, these factors may cause de-differentiation of the tumor cells leading to cancer stem cells that contribute to radio-, chemo- and immune-resistance and recurrence of tumors. On the other hand, they may also enhance the heterogeneity under specific microenvironment-driven proliferation. In this editorial, we intend to underline the importance of heterogeneity in cancer progress, its evaluation and its use in correlation with the tumor evolution in a specific patient as a field of research for achieving precise patient-tailored treatments and amelioration of diagnostic (monitoring) tools and prognostic capacity.


Asunto(s)
Neoplasias , Humanos , Neoplasias/genética , Neovascularización Patológica , Proliferación Celular/genética , Células Madre Neoplásicas , Matriz Extracelular , Microambiente Tumoral/genética
3.
Opt Express ; 30(7): 11973-11985, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35473128

RESUMEN

We report on the design of nanohole/nanobeam cavities in ridge waveguides for on-chip, quantum-dot-based single-photon generation. Our design overcomes limitations of a low-refractive-index-contrast material platform in terms of emitter-mode coupling efficiency and yields an outcoupling efficiency of 0.73 to the output ridge waveguide. Importantly, this high coupling efficiency is combined with broadband operation of 9 nm full-width half-maximum. We provide an explicit design procedure for identifying the optimum geometrical parameters according to the developed design. Besides, we fabricate and optically characterize a proof-of-concept waveguide structure. The results of the microphotoluminescence measurements provide evidence for cavity-enhanced spontaneous emission from the quantum dot, thus supporting the potential of our design for on-chip single-photon sources applications.

4.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36232398

RESUMEN

The immune checkpoint inhibitors have revolutionized cancer immunotherapy. These inhibitors are game changers in many cancers and for many patients, sometimes show unprecedented therapeutic efficacy. However, their therapeutic efficacy is largely limited in many solid tumors where the tumor-controlled immune microenvironment prevents the immune system from efficiently reaching, recognizing, and eliminating cancer cells. The tumor immune microenvironment is largely orchestrated by immune cells through which tumors gain resistance against the immune system. Among these cells are mast cells and dendritic cells. Both cell types possess enormous capabilities to shape the immune microenvironment. These capabilities stage these cells as cellular checkpoints in the immune microenvironment. Regaining control over these cells in the tumor microenvironment can open new avenues for breaking the resistance of solid tumors to immunotherapy. In this review, we will discuss mast cells and dendritic cells in the context of solid tumors and how these immune cells can, alone or in cooperation, modulate the solid tumor resistance to the immune system. We will also discuss how this modulation could be used in novel immunotherapeutic modalities to weaken the solid tumor resistance to the immune system. This weakening could then help other immunotherapeutic modalities engage against these tumors more efficiently.


Asunto(s)
Mastocitos , Neoplasias , Células Dendríticas/patología , Humanos , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Mastocitos/patología , Neoplasias/patología , Microambiente Tumoral
5.
Vet Med (Praha) ; 67(2): 99-104, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39171215

RESUMEN

Ovarian teratomas are rare neoplasms in female dogs, and they are characterised by the proliferation of tissues of embryonic origin. Most teratomas are benign, but a histological diagnosis is important for clinicians. The objective of this article is to describe a benign ovarian teratoma in a dog, which was found on the street and was appearing like pregnant. A veterinary inspection by palpation documented an enlarged abdomen with a mass of tough matter located on the right side in the abdominal-pelvic part. An ultrasound examination presumed neoplastic mass in region of ovary. A bilateral ovariohysterectomy was performed and the subsequent histological evaluation revealed a benign ovarian teratoma with a histochemically and immunohistochemically verified nervous tissue. After one year, no distant metastases were found and the dog was recognised as being clinically healthy without problems. On the basis of the ultrasonography diagnostics and histopathological analyses, we have demonstrated the occurrence of a benign ovarian teratoma in a dog.

6.
Int J Mol Sci ; 22(19)2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34639025

RESUMEN

The concept of trained immunity has become one of the most interesting and potentially commercially and clinically relevant ideas of current immunology. Trained immunity is realized by the epigenetic reprogramming of non-immunocompetent cells, primarily monocytes/macrophages and natural killer (NK) cells, and is less specific than adaptive immunity; therefore, it may cross-protect against other infectious agents. It remains possible, however, that some of the observed changes are simply caused by increased levels of immune reactions resulting from supplementation with immunomodulators, such as glucan. In addition, the question of whether we can talk about trained immunity in cells with a life span of only few days is still unresolved.


Asunto(s)
Inmunidad Adaptativa , Inmunidad Innata , Animales , Susceptibilidad a Enfermedades , Homeostasis/inmunología , Humanos , Inmunidad Celular , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Leucocitos/inmunología , Leucocitos/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , beta-Glucanos/metabolismo
7.
Medicina (Kaunas) ; 57(3)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799911

RESUMEN

Cancer, bacteria, and immunity relationships are much-debated topics in the last decade. Microbiome's importance for metabolic and immunologic modulation of the organism adaptation and responses has become progressively evident, and models to study these relationships, especially about carcinogenesis, have acquired primary importance. The availability of germ-free (GF) animals, i.e., animals born and maintained under completely sterile conditions avoiding the microbiome development offers a unique tool to investigate the role that bacteria can have in carcinogenesis and tumor development. The comparison between GF animals with the conventional (CV) counterpart with microbiome can help to evidence conditions and mechanisms directly involving bacterial activities in the modulation of carcinogenesis processes. Here, we review the literature about spontaneous cancer and cancer modeling in GF animals since the early studies, trying to offer a practical overview on the argument.


Asunto(s)
Vida Libre de Gérmenes , Microbiota , Animales , Bacterias , Carcinogénesis
8.
Cancer Immunol Immunother ; 69(2): 223-235, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31650200

RESUMEN

The lysyl oxidases (LOXs) are a family of enzymes deputed to cross-link collagen and elastin, shaping the structure and strength of the extracellular matrix (ECM). However, many novel "non-canonical" functions, alternative substrates, and regulatory mechanisms have been described and are being continuously elucidated. The activity of LOXs, therefore, appears to be integrated into a complex network of signals regulating many cell functions, including survival/proliferation/differentiation. Among these signaling pathways, TGF-ß and PI3K/Akt/mTOR, in particular, cross-talk extensively with each other and with LOXs also initiating complex feedback loops which modulate the activity of LOXs and direct the remodeling of the ECM. A growing body of evidence indicates that LOXs are not only important in the homeostasis of the normal structure of the ECM, but are also implicated in the establishment and maturation of the tumor microenvironment. LOXs' association with advanced and metastatic cancer is well established; however, there is enough evidence to support a significant role of LOXs in the transformation of normal epithelial cells, in the accelerated tumor development and the induction of invasion of the premalignant epithelium. A better understanding of LOXs and their interactions with the different elements of the tumor immune microenvironment will prove invaluable in the design of novel anti-tumor strategies.


Asunto(s)
Inmunidad , Neoplasias/etiología , Proteína-Lisina 6-Oxidasa/química , Proteína-Lisina 6-Oxidasa/inmunología , Microambiente Tumoral/inmunología , Animales , Biomarcadores , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Familia de Multigenes , Neoplasias/patología , Transducción de Señal , Relación Estructura-Actividad
9.
Scand J Immunol ; 91(2): e12833, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31544248

RESUMEN

Vaccination constitutes one of the major breakthroughs in human medicine. At the same time, development of more immunogenic vaccine alternatives to using aluminium-based adjuvants is one of the most important phases of vaccination development. Among different sources of carbohydrate polymers, including plants, microbes and synthetic sources tested, glucans were found to be the most promising vaccine adjuvant, as they alone stimulate various immune reactions including antibody production without any negative side effects. The use of glucan particles as a delivery system is a viable option based on the documented efficient antigen loading and receptor-targeted uptake in antigen-presenting cells. In addition to particles, soluble glucans can be used as novel hydrogels or as direct immunocyte-targeting delivery systems employing novel complexes with oligodeoxynucleotides. This review focuses on recent advances in glucan-based vaccine development from glucan-based conjugates to a glucan-based delivery and adjuvant platform.


Asunto(s)
Adyuvantes Inmunológicos , Sistemas de Liberación de Medicamentos/métodos , Hidrogeles/uso terapéutico , Vacunas/inmunología , beta-Glucanos/inmunología , Animales , Presentación de Antígeno , Humanos , Oligodesoxirribonucleótidos , Vacunación , beta-Glucanos/uso terapéutico
10.
Molecules ; 24(7)2019 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-30935016

RESUMEN

Glucans are part of a group of biologically active natural molecules and are steadily gaining strong attention not only as an important food supplement, but also as an immunostimulant and potential drug. This paper represents an up-to-date review of glucans (ß-1,3-glucans) and their role in various immune reactions and the treatment of cancer. With more than 80 clinical trials evaluating their biological effects, the question is not if glucans will move from food supplement to widely accepted drug, but how soon.


Asunto(s)
Adyuvantes Inmunológicos/química , Antineoplásicos/química , Suplementos Dietéticos , beta-Glucanos/química , Adyuvantes Inmunológicos/farmacología , Agaricales/química , Animales , Antineoplásicos/farmacología , Regulación de la Expresión Génica , Humanos , Sistema Inmunológico/efectos de los fármacos , Valor Nutritivo , Transducción de Señal , beta-Glucanos/farmacología
11.
Biologicals ; 42(3): 139-44, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24548911

RESUMEN

Mesenchymal stromal cells (MSC) are fibroblast-like cells present in different types of tissues. Their immunomodulatory potential represents a promising method for post-transplant immunotherapy in the treatment of GVHD (graft-versus-host disease) with suboptimal response to standard immunosuppression. In this study we tested influence of 1-8 month-long cryopreservation on ability of MSC to suppress activation of non-specifically stimulated lymphocytes. We did not observe any changes in proliferation capacity of MSC after thawing. Lymphocytes metabolic activity was inhibited by 30% and number of dividing cells was three times smaller in the presence of MSC. Two activation markers were studied (CD25 and CD69) to confirm preservation of functional cell integrity. Expression of CD25 antigen on CD3(+)CD4(+) and CD3(+)CD4(-) cells was decreased in all co-cultivated samples. Level of CD69 expression on CD3(+)CD4(+) cells was lower in samples with added MSC (10-15% on day +2) but without reaching statistical significance. The lower expression (approximately 5%) was observed also on CD4-cells. The study confirms the preservation of immunomodulatory properties of cryopreserved and re-expanded MSC. Aliquots with cryopreserved cells can represent an optimal source for a quick preparation of MSC cell product with the possibility to apply the same cells repeatedly.


Asunto(s)
Criopreservación , Enfermedad Injerto contra Huésped/terapia , Células Madre Mesenquimatosas/citología , Proliferación Celular , Humanos , Inmunofenotipificación , Activación de Linfocitos
12.
J Immunol Res ; 2024: 5537948, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39056014

RESUMEN

CD8+ T cells are essential for adaptive immunity against infection and tumors. Their ability to proliferate after stimulation is crucial to their functionality. Dendritic cells (DCs) are professional antigen-presenting cells that induce their proliferation. Here, we show that thapsigargin-induced LAD2 mast cell (MC) line-released products can impair the ability of monocyte-derived DCs to induce CD8+ T-cell proliferation and the generation of Th1 cytokine-producing T cells. We found that culture medium conditioned with LAD2 MCs previously stimulated with thapsigargin (thapsLAD2) induces maturation of DCs as determined by the maturation markers CD80, CD83, CD86, and HLA-DR. However, thapsLAD2-matured DCs produced no detectable TNFα or IL-12 during the maturation. In addition, although their surface expression of PD-L1 was comparable with the immature or TLR7/8-agonist (R848)-matured DCs, their TIM-3 expression was significantly higher than in immature DCs and even much higher than in R848-matured DCs. In addition, contrary to R848-matured DCs, the thapsLAD2-matured DCs only tended to induce enhanced proliferation of CD4+ T cells than immature DCs. For CD8+ T cells, this tendency was not even detected because thapsLAD2-matured and immature DCs comparably induced their proliferation, which contrasted with the significantly enhanced proliferation induced by R848-matured DCs. Furthermore, these differences were comparably recapitulated in the ability of the tested DCs to induce IFNγ- and IFNγ/TNFα-producing T cells. These findings show a novel mechanism of MC-mediated regulation of adaptive immune responses.


Asunto(s)
Linfocitos T CD8-positivos , Diferenciación Celular , Proliferación Celular , Células Dendríticas , Activación de Linfocitos , Mastocitos , Tapsigargina , Humanos , Células Dendríticas/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Tapsigargina/farmacología , Proliferación Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Mastocitos/inmunología , Mastocitos/efectos de los fármacos , Mastocitos/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Monocitos/inmunología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Citocinas/metabolismo , Imidazoles/farmacología , Línea Celular
13.
Mol Biol Rep ; 40(10): 5921-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24065530

RESUMEN

Altered expression and methylation pattern of tumor suppressor and DNA repair genes, in particular involved in mismatch repair (MMR) pathway, frequently occur in primary colorectal (CRC) tumors. However, little is known about (epi)genetic changes of these genes in precancerous and early stages of CRC. The aim of this pilot study was to analyze expression profile and promoter methylation status of important tumor suppressor and DNA repair genes in the early stages of experimentally induced colorectal carcinogenesis. Rats were treated with azoxymethane (AOM), dextran sodium sulphate (DSS) or with their combination, and sacrificed 1 or 4 months post-treatment period. The down-regulation of Apc expression in left colon, detectable in animals treated with DSS-AOM and sacrificed 1 month after the end of treatment, represents most early marker of the experimental colorectal carcinogenesis. Significantly reduced gene expressions were also found in 5 out of 7 studied MMR genes (Mlh1, Mlh3, Msh3 Pms1, Pms2), regarding the sequential administration of DSS-AOM at 4 months since the treatment. Strong down-regulation was also discovered for Apc, Apex1, Mgmt and TP53. Tumors developed in rectum-sigmoid region displayed significantly lower Apc and Pms2 expressions. The decreased expression of studied genes was not in any case associated with aberrant methylation of promoter region. Present data suggest that down-regulation of Apc and MMR genes are prerequisite for the development of CRC. In this study we addressed for the first time early functional alterations of tumor suppressor genes with underlying epigenetic mechanisms in experimentally induced CRC in rats.


Asunto(s)
Neoplasias del Colon/genética , Metilación de ADN/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Supresoras de Tumor/genética , Animales , Colon/metabolismo , Colon/patología , Masculino , Proyectos Piloto , Reacción en Cadena de la Polimerasa , Ratas , Ratas Wistar , Proteínas Supresoras de Tumor/metabolismo
14.
Nanoscale ; 15(13): 6156-6169, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36806428

RESUMEN

We present a detailed analysis of the physics governing the collection efficiency and the Purcell enhancement of the nanopost single-photon source. We show that a standard single-mode Fabry-Pérot model is insufficient to describe the device performance, which benefits significantly from scattering from the fundamental mode to radiation modes. We show how the scattering mechanism decouples the collection efficiency from the Purcell enhancement, such that maximum collection efficiency is obtained off-resonance. Finally, we discuss how this scattering mechanism can be beneficial for future single-photon source designs.

15.
Foods ; 12(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36981048

RESUMEN

For centuries human civilization has cultivated oats, and now they are consumed in various forms of food, from instant breakfasts to beverages. They are a nutrient-rich food containing linear mixed-linkage (1 → 3) (1 → 4)-ß-d-glucans, which are relatively well soluble in water and responsible for various biological effects: the regulation of the blood cholesterol level, as well as being anti-inflammatory, prebiotic, antioxidant, and tumor-preventing. Numerous studies, especially in the last two decades, highlight the differences in the biological properties of the oat ß-d-glucan fractions of low, medium, and high molecular weight. These fractions differ in their features due to variations in bioavailability related to the rheological properties of these polysaccharides, and their association with food matrices, purity, and mode of preparation or modification. There is strong evidence that, under different conditions, the molecular weight may determine the potency of oat-extracted ß-d-glucans. In this review, we intend to give a concise overview of the properties and studies of the biological activities of oat ß-d-glucan preparations depending on their molecular weight and how they represent a prospective ingredient of functional food with the potential to prevent or modulate various pathological conditions.

16.
Sci Rep ; 13(1): 19079, 2023 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-37925511

RESUMEN

Soft tissue sarcomas are aggressive mesenchymal-origin malignancies. Undifferentiated pleomorphic sarcoma (UPS) belongs to the aggressive, high-grade, and least characterized sarcoma subtype, affecting multiple tissues and metastasizing to many organs. The treatment of localized UPS includes surgery in combination with radiation therapy. Metastatic forms are treated with chemotherapy. Immunotherapy is a promising treatment modality for many cancers. However, the development of immunotherapy for UPS is limited due to its heterogeneity, antigenic landscape variation, lower infiltration with immune cells, and a limited number of established patient-derived UPS cell lines for preclinical research. In this study, we established and characterized a novel patient-derived UPS cell line, JBT19. The JBT19 cells express PD-L1 and collagen, a ligand of the immune checkpoint molecule LAIR-1. JBT19 cells can form spheroids in vitro and solid tumors in immunodeficient nude mice. We found JBT19 cells induce expansion of JBT19-reactive autologous and allogeneic NK, T, and NKT-like cells, and the reactivity of the expanded cells was associated with cytotoxic impact on JBT19 cells. The PD-1 and LAIR-1 ligand-expressing JBT19 cells show ex vivo immunogenicity and effective in vivo xenoengraftment properties that can offer a unique resource in the preclinical research developing novel immunotherapeutic interventions in the treatment of UPS.


Asunto(s)
Histiocitoma Fibroso Maligno , Sarcoma , Ratones , Animales , Humanos , Antígeno B7-H1/metabolismo , Ratones Desnudos , Ligandos , Sarcoma/patología , Inmunoterapia , Línea Celular
17.
Ann Transl Med ; 9(14): 1186, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34430627

RESUMEN

Andrographolide is a labdane diterpenoid isolated from Andrographis paniculata and traditionally used in Chinese and Indian medicine. Reported effects include anti-bacterial, anti-inflammatory and anti-cancer functions. Most of the studies support the hypothesis that andrographolide supplementation stimulates immune system, so the observed effects migh in fact be secondary to the stimulation of defense reactions. As andrographolide is involved in regulation of inflammation, it is not surprising that it is also evaluated in inflammation-mediated diseases such as ulcerative colitis. Anticancer effects of the andrographolide have been tested on various cancer panels. Colon cancer, breast cancer, and head and neck carcinomas were the most investigated, followed by prostate cancer and glioblastoma. The results looked promising. However, problems with solubility and low level of active substance in natural extract leads to preparation of chemical analogs. Objective of this short review is to summarize current knowledge of the biological effects of andragrapholide. We conclude that despite documented effects and some partly characterized mechanisms of action, more research is clearly needed. At present, the doses, types of treatment and possible negative side effects are not yet established. In addition, various isolations and compound formulas have been used for treatment of various diseases, making final conclusions problematic.

18.
J Immunotoxicol ; 18(1): 37-49, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33749490

RESUMEN

Germ-free animals (GF) are those without a microbiome since birth. This particular biological model has become one of special interest with the growing evidence of importance of the microbiome in the life, development, adaptation, and immunity of humans and animals in the environments in which they live. Anatomical differences observed in GF compared with conventionally-reared animals (CV) has given rise to the question of the influence of commensal microflora on the development of structure and function (even immunological) of the bowel. Only recently, thanks to achievements in microscopy and associated methods, structural differences can be better evaluated and put in perspective with the immunological characteristics of GF vs. CV animals. This study, using a GF rat model, describes for the first time the possible influence that the presence of commensal microflora, continuously stimulating mucosal immunity, has on the collagen scaffold organization of the colon mucosa. Significant differences were found between CV and GF mucosa structure with higher complexity in the CV rats associated to a more activated immune environment. The immunological data suggest that, in response to the presence of a microbiome, an effective homeostatic regulation in developed by the CV rats in healthy conditions to avoid inflammation and maintain cytokine levels near the spontaneous production found in the GF animals. The results indicated that collagen scaffold adapted to the immune microenvironment; therefore, it is apparent that the microbiome was able to condition the structure of the colon mucosa.


Asunto(s)
Vida Libre de Gérmenes , Microbiota , Animales , Colon , Inmunidad Mucosa , Mucosa Intestinal , Ratas
19.
Cancers (Basel) ; 13(10)2021 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-34070183

RESUMEN

Continuous activation of the immune system inside a tissue can lead to remodelling of the tissue structure and creation of a specific microenvironment, such as during the tumour development. Chronic inflammation is a central player in stimulating changes that alter the tissue stroma and can lead to fibrotic evolution. In the colon mucosa, regulatory mechanisms, including TGF-ß1, avoid damaging inflammation in front of the continuous challenge by the intestinal microbiome. Inducing either DSS colitis or AOM colorectal carcinogenesis in AVN-Wistar rats, we evaluated at one month after the end of each treatment whether immunological changes and remodelling of the collagen scaffold were already in development. At this time point, we found in both models a general downregulation of pro-inflammatory cytokines and even of TGF-ß1, but not of IL-6. Moreover, we demonstrated by multi-photon microscopy the simultaneously presence of pro-fibrotic remodelling of the collagen scaffold, with measurable changes in comparison to the control mucosa. The scaffold was significantly modified depending on the type of induced stimulation. These results suggest that at one month after the end of the DSS or AOM inductions, a smouldering inflammation is present in both induced conditions, since the pro-inflammatory cytokines still exceed, in proportion, the local homeostatic regulation of which TGF-ß1 is a part (inflammatory threshold). Such an inflammation appears sufficient to sustain remodelling of the collagen scaffold that may be taken as a possible pathological marker for revealing pre-neoplastic inflammation.

20.
Mucosal Immunol ; 14(2): 511-522, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32973324

RESUMEN

Mucosal surfaces are colonized by highly diverse commensal microbiota. Coating with secretory IgA (SIgA) promotes the survival of commensal bacteria while it inhibits the invasion by pathogens. Bacterial coating could be mediated by antigen-specific SIgA recognition, polyreactivity, and/or by the SIgA-associated glycans. In contrast to many in vitro studies, only a few reported the effect of SIgA glycans in vivo. Here, we used a germ-free antibody-free newborn piglets model to compare the protective effect of SIgA, SIgA with enzymatically removed N-glycans, Fab, and Fc containing the secretory component (Fc-SC) during oral necrotoxigenic E. coli O55 challenge. SIgA, Fab, and Fc-SC were protective, whereas removal of N-glycans from SIgA reduced SIgA-mediated protection as demonstrated by piglets' intestinal histology, clinical status, and survival. In vitro analyses indicated that deglycosylation of SIgA did not reduce agglutination of E. coli O55. These findings highlight the role of SIgA-associated N-glycans in protection. Further structural studies of SIgA-associated glycans would lead to the identification of those involved in the species-specific inhibition of attachment to corresponding epithelial cells.


Asunto(s)
Infecciones por Escherichia coli/inmunología , Escherichia coli/fisiología , Inmunoglobulina A Secretora/metabolismo , Fragmentos Fab de Inmunoglobulinas/metabolismo , Polisacáridos/metabolismo , Anticuerpos de Cadena Única/metabolismo , Aglutinación , Animales , Animales Recién Nacidos , Resistencia a la Enfermedad , Femenino , Vida Libre de Gérmenes , Glicosilación , Embarazo , Porcinos
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