RESUMEN

Several natural products are being studied to identify new bioactive molecules with therapeutic potential for infections, immune modulation, and other pathologies. TLRs are a family of receptors that play a crucial role in the immune system, constituting the first line of immune defense. They recognize specific products derived from microorganisms that activate multiple pathways and transcription factors in target cells, which are vital for producing immune mediators. Mygalin is a synthetic acylpolyamine derived from hemocytes of the spider Acanthoscurria gomesiana. This molecule negatively regulates macrophage response to LPS stimulation by interacting with MD2 in the TLR4/MD2 complex. Here, we investigated the activity of Mygalin mediated by TLR2 agonists in cells treated with Pam3CSK4 (TLR2/1), Pam2CSK4, Zymosan (TLR2/6), and IFN-γ. Our data showed that Mygalin significantly inhibited stimulation with agonists and IFN-γ, reducing NO and IL-6 synthesis, regardless of the stimulation. There was also a significant reduction in the phosphorylation of proteins NF-κB p65 and STAT-1 in cells treated with Pam3CSK4. Molecular docking assays determined the molecular structure of Mygalin and agonists Pam3CSK4, Pam2CSK4, and Zymosan, as well as their interaction and free energy with the heterodimeric complexes TLR2/1 and TLR2/6. Mygalin interacted with the TLR1 and TLR2 dimer pathway through direct interaction with the agonists, and the ligand-binding domain was similar in both complexes. However, the binding of Mygalin was different from that of the agonists, since the interaction energy with the receptors was lower than with the agonists for their receptors. In conclusion, this study showed the great potential of Mygalin as a potent natural inhibitor of TLR2/1 and TLR2/6 and a suppressor of the inflammatory response induced by TLR2 agonists, in part due to its ability to interact with the heterodimeric complexes.

Asunto(s)

Interferón gamma , Receptor Toll-Like 2 , Receptor Toll-Like 2/agonistas , Receptor Toll-Like 2/metabolismo , Animales , Interferón gamma/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Lipopéptidos/farmacología , Células RAW 264.7 , Humanos , Transducción de Señal/efectos de los fármacos , Zimosan/farmacología , Interleucina-6/metabolismo , Polisacáridos/farmacología , Polisacáridos/química , Factor de Transcripción ReIA/metabolismo

RESUMEN

Natural killer (NK) cells play a crucial role in innate immunity, particularly in combating infections and tumors. However, in hematological cancers, NK cells often exhibit impaired functions. Therefore, it is very important to activate its endosomal Toll-like receptors (TLRs) as a potential strategy to restore its antitumor activity. We stimulated NK cells from the peripheral blood mononuclear cells from children with acute lymphoblastic leukemia and NK cells isolated, and the NK cells were stimulated with specific TLR ligands (Poly I:C, Imiquimod, R848, and ODN2006) and we evaluated changes in IFN-γ, CD107a, NKG2D, NKp44 expression, Granzyme B secretion, cytokine/chemokine release, and cytotoxic activity. Results revealed that Poly I:C and Imiquimod enhanced the activation of both immunoregulatory and cytotoxic NK cells, increasing IFN-γ, CD107a, NKG2D, and NKp44 expression. R848 activated immunoregulatory NK cells, while ODN2006 boosted CD107a, NKp44, NKG2D, and IFN-γ secretion in cytotoxic NK cells. R848 also increased the secretion of seven cytokines/chemokines. Importantly, R848 and ODN 2006 significantly improved cytotoxicity against leukemic cells. Overall, TLR stimulation enhances NK cell activation, suggesting TLR8 (R848) and TLR9 (ODN 2006) ligands as promising candidates for antitumor immunotherapy.

Asunto(s)

Imiquimod , Células Asesinas Naturales , Activación de Linfocitos , Poli I-C , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores Toll-Like , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Poli I-C/farmacología , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Imiquimod/farmacología , Receptores Toll-Like/metabolismo , Receptores Toll-Like/agonistas , Niño , Oligodesoxirribonucleótidos/farmacología , Citocinas/metabolismo , Femenino , Interferón gamma/metabolismo , Masculino , Imidazoles/farmacología , Citotoxicidad Inmunológica/efectos de los fármacos , Preescolar , Agonistas de los Receptores Toll-Like

RESUMEN

The SARS-CoV-2 outbreak has provoked more than 6 million deaths worldwide. The scarcity of effective treatments and its virulence converted the vaccines into an essential tool to face it. The most used vaccines were the mRNA, adenovirus vector, and inactivated whole-virus. However, nowadays, infants aged < 6 months are not eligible for any vaccines against COVID-19, and their immunization relies on passive immunity. In this research, we investigated the humoral and cellular immune response generated on newborns of SARS-CoV-2 vaccinated mothers with mRNA or viral vector (VV) vaccine employing Fourier transformed infrared (FTIR) spectroscopy in saliva samples. For this purpose, saliva samples of newborns and their mothers were collected; the population was divided into two groups, VV and mRNA, which were subdivided into three subgroups: before pregnancy (BP), at the first (FTP) and second (STP) trimesters of pregnancy. The samples were analyzed using FTIR spectroscopy, and the bands associated with the humoral and cellular immune responses, such as IgG, IgA, and IFN-γ were analyzed. The integrated areas were calculated and compared to elucidate the quantity of those immunoglobins and the cytokine. Likewise, the correlation of the humoral and cellular immune response between the newborns and their mothers and the correlation between cellular and humoral immune response was also evaluated. The VV vaccine produced a significant humoral and cellular immune response in newborns and their mothers when they received it at the STP compared with the mRNA vaccine, evidencing statistical significance. However, no correlation was observed between newborns and their mothers when the vaccine was applied in this trimester of pregnancy. When administered BP, the mRNA vaccine generated more humoral immunity in newborns and their mothers. Nevertheless, compared with the VV vaccine, it only showed statistical significance in the mothers, highlighting that IgG showed a moderate positive correlation between the newborns and their mothers.

Asunto(s)

Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Vacunación , Humanos , Femenino , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Recién Nacido , COVID-19/prevención & control , COVID-19/inmunología , Embarazo , Vacunación/métodos , SARS-CoV-2/inmunología , Vacunas contra la COVID-19/inmunología , Adulto , Madres , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/análisis , Inmunidad Humoral , Saliva/inmunología , Inmunidad Celular , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina A/inmunología , Inmunoglobulina A/análisis , Interferón gamma/metabolismo , Vacunas de ARNm/inmunología

RESUMEN

Brucella abortus (Ba) is a pathogen that survives inside macrophages. Despite being its preferential niche, Ba infects other cells, as shown by the multiple signs and symptoms humans present. This pathogen can evade our immune system. Ba displays a mechanism of down-modulating MHC-I on monocytes/macrophages in the presence of IFN-γ (when Th1 response is triggered) without altering the total expression of MHC-I. The retained MHC-I proteins are located within the Golgi Apparatus (GA). The RNA of Ba is one of the PAMPs that trigger this phenomenon. However, we acknowledged whether this event could be triggered in other cells relevant during Ba infection. Here, we demonstrate that Ba RNA reduced the surface expression of MHC-I induced by IFN-γ in the human bronchial epithelium (Calu-6), the human alveolar epithelium (A-549) and the endothelial microvasculature (HMEC) cell lines. In Calu-6 and HMEC cells, Ba RNA induces the retention of MHC-I in the GA. This phenomenon was not observed in A-549 cells. We then evaluated the effect of Ba RNA on the secretion of IL-8, IL-6 and MCP-1, key cytokines in Ba infection. Contrary to our expectations, HMEC, Calu-6 and A-549 cells treated with Ba RNA had higher IL-8 and IL-6 levels compared to untreated cells. In addition, we showed that Ba RNA down-modulates the MHC-I surface expression induced by IFN-γ on human monocytes/macrophages via the pathway of the Epidermal Growth Factor Receptor (EGFR). So, cells were stimulated with an EGFR ligand-blocking antibody (Cetuximab) and Ba RNA. Neutralization of the EGFR to some extent reversed the down-modulation of MHC-I mediated by Ba RNA in HMEC and A-549 cells. In conclusion, this is the first study exploring a central immune evasion strategy, such as the downregulation of MHC-I surface expression, beyond monocytes and could shed light on how it persists effectively within the host, enduring unseen and escaping CD8+ T cell surveillance.

Asunto(s)

Brucella abortus , Células Endoteliales , Células Epiteliales , Antígenos de Histocompatibilidad Clase I , Interferón gamma , Humanos , Interferón gamma/metabolismo , Interferón gamma/farmacología , Células Endoteliales/metabolismo , Células Endoteliales/microbiología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Células Epiteliales/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , ARN Bacteriano/genética , Línea Celular , Regulación hacia Abajo/efectos de los fármacos , Receptores ErbB/metabolismo , Brucelosis/inmunología , Brucelosis/metabolismo , Brucelosis/microbiología , Brucelosis/genética , Aparato de Golgi/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Monocitos/metabolismo , Monocitos/inmunología , Monocitos/efectos de los fármacos

RESUMEN

Protein ADP-ribosylation plays important but ill-defined roles in antiviral signalling cascades such as the interferon response. Several viruses of clinical interest, including coronaviruses, express hydrolases that reverse ADP-ribosylation catalysed by host enzymes, suggesting an important role for this modification in host-pathogen interactions. However, which ADP-ribosyltransferases mediate host ADP-ribosylation, what proteins and pathways they target and how these modifications affect viral infection and pathogenesis is currently unclear. Here we show that host ADP-ribosyltransferase activity induced by IFNγ signalling depends on PARP14 catalytic activity and that the PARP9/DTX3L complex is required to uphold PARP14 protein levels via post-translational mechanisms. Both the PARP9/DTX3L complex and PARP14 localise to IFNγ-induced cytoplasmic inclusions containing ADP-ribosylated proteins, and both PARP14 itself and DTX3L are likely targets of PARP14 ADP-ribosylation. We provide evidence that these modifications are hydrolysed by the SARS-CoV-2 Nsp3 macrodomain, shedding light on the intricate cross-regulation between IFN-induced ADP-ribosyltransferases and the potential roles of the coronavirus macrodomain in counteracting their activity.

Asunto(s)

ADP-Ribosilación , Interferón gamma , Poli(ADP-Ribosa) Polimerasas , Humanos , Poli(ADP-Ribosa) Polimerasas/metabolismo , Interferón gamma/metabolismo , Interacciones Huésped-Patógeno , Células HEK293 , ADP Ribosa Transferasas/metabolismo , ADP Ribosa Transferasas/genética , Procesamiento Proteico-Postraduccional , SARS-CoV-2/metabolismo , Proteínas de Neoplasias , Ubiquitina-Proteína Ligasas

RESUMEN

Introduction: Several effective vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed and implemented in the population. However, the current production capacity falls short of meeting global demand. Therefore, it is crucial to further develop novel vaccine platforms that can bridge the distribution gap. AVX/COVID-12 is a vector-based vaccine that utilizes the Newcastle Disease virus (NDV) to present the SARS-CoV-2 spike protein to the immune system. Methods: This study aims to analyze the antigenicity of the vaccine candidate by examining antibody binding and T-cell activation in individuals infected with SARS-CoV-2 or variants of concern (VOCs), as well as in healthy volunteers who received coronavirus disease 2019 (COVID-19) vaccinations. Results: Our findings indicate that the vaccine effectively binds antibodies and activates T-cells in individuals who received 2 or 3 doses of BNT162b2 or AZ/ChAdOx-1-S vaccines. Furthermore, the stimulation of T-cells from patients and vaccine recipients with AVX/COVID-12 resulted in their proliferation and secretion of interferon-gamma (IFN-γ) in both CD4+ and CD8+ T-cells. Discussion: The AVX/COVID-12 vectored vaccine candidate demonstrates the ability to stimulate robust cellular responses and is recognized by antibodies primed by the spike protein present in SARS-CoV-2 viruses that infected patients, as well as in the mRNA BNT162b2 and AZ/ChAdOx-1-S vaccines. These results support the inclusion of the AVX/COVID-12 vaccine as a booster in vaccination programs aimed at addressing COVID-19 caused by SARS-CoV-2 and its VOCs.

Asunto(s)

Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Activación de Linfocitos , Virus de la Enfermedad de Newcastle , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , COVID-19/inmunología , COVID-19/prevención & control , SARS-CoV-2/inmunología , Anticuerpos Antivirales/inmunología , Virus de la Enfermedad de Newcastle/inmunología , Vacunas contra la COVID-19/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Activación de Linfocitos/inmunología , Adulto , Femenino , Masculino , Persona de Mediana Edad , Linfocitos T/inmunología , Vacuna BNT162/inmunología , Vacunación , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo

RESUMEN

Plasmacytoid dendritic cells (pDCs) are vital players in antiviral immune responses because of their high levels of IFN-α secretion. However, this attribute has also implicated them as critical factors behind the immunopathogenesis of inflammatory diseases, and no currently available therapy can efficiently inhibit pDCs' aberrant activation. Mesenchymal stromal cells (MSCs) possess stromal immunomodulatory functionality, regulating immune cell activation through several mechanisms, including the adenosinergic (CD39/CD73/adenosine) pathway. The IFN-γ preconditioning of bone marrow MSCs improves their inhibitory properties for therapy applications; however, isolating human gingival tissue-derived MSCs (hGMSCs) is more accessible. These cells have shown better immunomodulatory effects, yet the outcome of IFN-γ preconditioning and its impact on the adenosinergic pathway has not been evaluated. This study first validated the immunoregulatory properties of primary-cultured hGMSCs, and the results showed that IFN-γ preconditioning strengthens CD39/CD73 coexpression, adenosine production, and the regulatory properties of hGMSC, which were confirmed by describing for the first time their ability to reduce pDC activation and their IFN-α secretion and to increase the frequency of CD73+ pDC. In addition, when CD73's enzymatic activity was neutralized in hGMSCs, adenosine production and the IFN-γ preconditioning effect were restrained. This evidence might be applied to design hGMSCs- and adenosine-based immunotherapeutic strategies for treating inflammatory disorders that are associated with pDC overactivation.

Asunto(s)

5'-Nucleotidasa , Adenosina , Células Dendríticas , Encía , Interferón gamma , Células Madre Mesenquimatosas , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/citología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Adenosina/metabolismo , Interferón gamma/metabolismo , Encía/citología , 5'-Nucleotidasa/metabolismo , Células Cultivadas , Apirasa/metabolismo , Proteínas Ligadas a GPI

RESUMEN

BACKGROUND: In most cases, Zika virus (ZIKV) causes a self-limited acute illness in adults, characterized by mild clinical symptoms that resolve within a few days. Immune responses, both innate and adaptive, play a central role in controlling and eliminating virus-infected cells during the early stages of infection. AIM: To test the hypothesis that circulating T cells exhibit phenotypic and functional activation characteristics during the viremic phase of ZIKV infection. METHODS: A comprehensive analysis using mass cytometry was performed on peripheral blood mononuclear cells obtained from patients with acute ZIKV infection (as confirmed by RT-PCR) and compared with that from healthy donors (HD). The frequency of IFN-γ-producing T cells in response to peptide pools covering immunogenic regions of structural and nonstructural ZIKV proteins was quantified using an ELISpot assay. RESULTS: Circulating CD4+ and CD8+ T lymphocytes from ZIKV-infected patients expressed higher levels of IFN-γ and pSTAT-5, as well as cell surface markers associated with proliferation (Ki-67), activation ((HLA-DR, CD38) or exhaustion (PD1 and CTLA-4), compared to those from HD. Activation of CD4+ and CD8+ memory T cell subsets, including Transitional Memory T Cells (TTM), Effector Memory T cells (TEM), and Effector Memory T cells Re-expressing CD45RA (TEMRA), was prominent among CD4+ T cell subset of ZIKV-infected patients and was associated with increased levels of IFN-γ, pSTAT-5, Ki-67, CTLA-4, and PD1, as compared to HD. Additionally, approximately 30% of ZIKV-infected patients exhibited a T cell response primarily directed against the ZIKV NS5 protein. CONCLUSION: Circulating T lymphocytes spontaneously produce IFN-γ and express elevated levels of pSTAT-5 during the early phase of ZIKV infection whereas recognition of ZIKV antigen results in the generation of virus-specific IFN-γ-producing T cells.

Asunto(s)

Linfocitos T CD8-positivos , Interferón gamma , Infección por el Virus Zika , Virus Zika , Humanos , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/epidemiología , Adulto , Virus Zika/inmunología , Femenino , Masculino , Interferón gamma/metabolismo , Interferón gamma/inmunología , Brasil/epidemiología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD4-Positivos/inmunología , Persona de Mediana Edad , Adulto Joven , Epidemias , Activación de Linfocitos/inmunología , Linfocitos T/inmunología

RESUMEN

Toxoplasmosis is the most prevalent parasitic zoonosis worldwide, causing ocular and neurological diseases. No vaccine has been approved for human use. We evaluated the response of peripheral blood mononuclear cells (PBMCs) to a novel construct of Toxoplasma gondii total antigen in maltodextrin nanoparticles (NP/TE) in individuals with varying infectious statuses (uninfected, chronic asymptomatic, or ocular toxoplasmosis). We analyzed the concentration of IFN-γ after NP/TE ex vivo stimulation using ELISA and the immunophenotypes of CD4+ and CD8+ cell populations using flow cytometry. In addition, serotyping of individuals with toxoplasmosis was performed by ELISA using GRA6-derived polypeptides. Low doses of NP/TE stimulation (0.9 µg NP/0.3 µg TE) achieved IFN-γ-specific production in previously exposed human PBMCs without significant differences in the infecting serotype. Increased IFN-γ expression in CD4+ effector memory cell subsets was found in patients with ocular toxoplasmosis with NP/TE but not with TE alone. This is the first study to show how T-cell subsets respond to ex vivo stimulation with a vaccine candidate for human toxoplasmosis, providing crucial insights for future clinical trials.

Asunto(s)

Antígenos de Protozoos , Interferón gamma , Activación de Linfocitos , Nanopartículas , Polisacáridos , Toxoplasma , Toxoplasmosis , Humanos , Nanopartículas/química , Polisacáridos/inmunología , Toxoplasma/inmunología , Antígenos de Protozoos/inmunología , Toxoplasmosis/inmunología , Interferón gamma/metabolismo , Interferón gamma/inmunología , Activación de Linfocitos/inmunología , Femenino , Adulto , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Masculino , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Persona de Mediana Edad

RESUMEN

New adjuvant strategies are needed to improve protein-based subunit vaccine immunogenicity. We examined the potential to use nanostructure of 6-O-ascorbyl palmitate to formulate ovalbumin (OVA) protein and an oligodeoxynucleotide (CpG-ODN) (OCC). In mice immunized with a single dose, OCC elicited an OVA-specific immune response superior to OVA/CpG-ODN solution (OC). Rheological studies demonstrated OCC's self-assembling viscoelastic properties. Biodistribution studies indicated that OCC prolonged OVA and CpG-ODN retention at injection site and lymph nodes, reducing systemic spread. Flow-cytometry assays demonstrated that OCC promoted OVA and CpG-ODN co-uptake by Ly6ChiCD11bhiCD11c+ monocytes. OCC and OC induced early IFN-γ in lymph nodes, but OCC led to higher concentration. Conversely, mice immunized with OC showed higher serum IFN-γ concentration compared to those immunized with OCC. In mice immunized with OCC, NK1.1+ cells were the IFN-γ major producers, and IFN-γ was essential for OVA-specific IgG2c switching. These findings illustrate how this nanostructure improves vaccine's response.

Asunto(s)

Nanoestructuras , Oligodesoxirribonucleótidos , Ovalbúmina , Vacunas de Subunidad , Animales , Nanoestructuras/química , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/química , Vacunas de Subunidad/farmacocinética , Ratones , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/farmacocinética , Ovalbúmina/inmunología , Ovalbúmina/química , Femenino , Ratones Endogámicos C57BL , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacocinética , Interferón gamma/metabolismo , Distribución Tisular , Ácido Ascórbico/análogos & derivados

RESUMEN

This work evaluated aspects of the immune response of BALB/c mice infected with Corynebacterium pseudotuberculosis (T1 and C57). The fifteen BALB/c mice were euthanized after 70 days of infection and morphologically evaluated, also analyzing the innate and adaptive immune responses. The C57 strain induced more pronounced morphological changes than the T1 strain. There was an increase in CD4+ and CD8+ T cells identified during infection with the C57 strain. Cytokines of the inflammatory profile IL-1α and IL-6 and regulatory IL-13 and IL-10 presented significant differences. Cytokines IL-2, IL-4, INF-γ, IL-22, IL-21, and IL-27 did not differ significantly between groups. The obtained results contribute to a better understanding of the type of response and the immunological mechanisms involved during infection with different strains of C. pseudotuberculosis.

Asunto(s)

Linfocitos T CD8-positivos , Infecciones por Corynebacterium , Corynebacterium pseudotuberculosis , Citocinas , Ratones Endogámicos BALB C , Animales , Corynebacterium pseudotuberculosis/inmunología , Infecciones por Corynebacterium/inmunología , Infecciones por Corynebacterium/microbiología , Ratones , Citocinas/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD4-Positivos/inmunología , Interleucina-10 , Inmunidad Adaptativa , Inmunidad Innata , Interleucina-6 , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Interleucina-1alfa/metabolismo , Interleucina-1alfa/inmunología , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Interleucinas , Interleucina-2/metabolismo

RESUMEN

Cumulative evidence has established that Interferon (IFN)-γ has both pathogenic and protective roles in Multiple Sclerosis and the animal model, Experimental Autoimmune Encephalomyelitis (EAE). However, the underlying mechanisms to the beneficial effects of IFN-γ are not well understood. In this study, we found that IFN-γ exerts therapeutic effects on chronic, relapsing-remitting, and chronic progressive EAE models. The frequency of regulatory T (Treg) cells in spinal cords from chronic EAE mice treated with IFN-γ was significantly increased with no effect on Th1 and Th17 cells. Consistently, depletion of FOXP3-expressing cells blocked the protective effects of IFN-γ, indicating that the therapeutic effect of IFN-γ depends on the presence of Treg cells. However, IFN-γ did not trigger direct in vitro differentiation of Treg cells. In vivo administration of blocking antibodies against either interleukin (IL)-10, transforming growth factor (TGF)-ß or program death (PD)-1, revealed that the protective effects of IFN-γ in EAE were also dependent on TGF-ß and PD-1, but not on IL-10, suggesting that IFN-γ might have an indirect role on Treg cells acting through antigen-presenting cells. Indeed, IFN-γ treatment increased the frequency of a subset of splenic CD11b+ myeloid cells expressing TGF-ß-Latency Associated Peptide (LAP) and program death ligand 1 (PD-L1) in a signal transducer and activator of transcription (STAT)-1-dependent manner. Furthermore, splenic CD11b+ cells from EAE mice preconditioned in vitro with IFN-γ and myelin oligodendrocyte glycoprotein (MOG) peptide exhibited a tolerogenic phenotype with the capability to induce conversion of naïve CD4+ T cells mediated by secretion of TGF-ß. Remarkably, adoptive transfer of splenic CD11b+ cells from IFN-γ-treated EAE mice into untreated recipient mice ameliorated clinical symptoms of EAE and limited central nervous system infiltration of mononuclear cells and effector helper T cells. These results reveal a novel cellular and molecular mechanism whereby IFN-γ promotes beneficial effects in EAE by endowing splenic CD11b+ myeloid cells with tolerogenic and therapeutic activities.

Asunto(s)

Antígeno CD11b , Encefalomielitis Autoinmune Experimental , Interferón gamma , Ratones Endogámicos C57BL , Células Mieloides , Bazo , Animales , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Ratones , Interferón gamma/metabolismo , Células Mieloides/efectos de los fármacos , Células Mieloides/inmunología , Células Mieloides/metabolismo , Bazo/inmunología , Antígeno CD11b/metabolismo , Femenino , Glicoproteína Mielina-Oligodendrócito/toxicidad , Glicoproteína Mielina-Oligodendrócito/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Fragmentos de Péptidos/farmacología , Factor de Crecimiento Transformador beta/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Receptor de Muerte Celular Programada 1/inmunología , Factores de Transcripción Forkhead/metabolismo , Modelos Animales de Enfermedad

RESUMEN

Rotavirus is the main cause of acute diarrhea in children up to five years of age. In this regard, probiotics are commonly used to treat or prevent gastroenteritis including viral infections. The anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana, by reducing viral infectivity and improving IFN-type I response, has been previously reported. The present study aimed to study the effect of B. longum and/or C. sorokiniana on modulating the antiviral cellular immune response mediated by IFN-γ, IL-10, SOCS3, STAT1, and STAT2 genes in rotavirus-infected cells. To determine the mRNA relative expression of these genes, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection. In addition, infected cells were treated with B. longum and/or C. sorokiniana. Cellular RNA was purified, used for cDNA synthesis, and amplified by qPCR. Our results demonstrated that the combination of B. longum and C. sorokiniana stimulates the antiviral cellular immune response by upregulating IFN-γ and may block pro-inflammatory cytokines by upregulating IL-10 and SOCS3. The results of our study indicated that B. longum, C. sorokiniana, or their combination improve antiviral cellular immune response and might modulate pro-inflammatory responses.

Asunto(s)

Bifidobacterium longum , Chlorella , Interferón gamma , Interleucina-10 , Probióticos , Infecciones por Rotavirus , Proteína 3 Supresora de la Señalización de Citocinas , Humanos , Células HT29 , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Probióticos/farmacología , Rotavirus/fisiología , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/virología , Factor de Transcripción STAT1/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo

RESUMEN

Tumor-associated macrophages (TAM) are abundant in several tumor types and usually correlate with poor prognosis. Previously, we demonstrated that anti-inflammatory macrophages (M2) inhibit NK cell effector functions. Here, we explored the impact of TAM on NK cells in the context of clear-cell renal cell carcinoma (ccRCC). Bioinformatics analysis revealed that an exhausted NK cell signature strongly correlated with an M2 signature. Analysis of TAM from human ccRCC samples confirmed that they exhibited an M2-skewed phenotype and inhibited IFN-γ production by NK cells. Moreover, human M0 macrophages cultured with conditioned media from ccRCC cell lines generated macrophages with an M2-skewed phenotype (TAM-like), which alike TAM, displayed suppressive activity on NK cells. Moreover, TAM depletion in the mouse Renca ccRCC model resulted in delayed tumor growth and reduced volume, accompanied by an increased frequency of IFN-γ-producing tumor-infiltrating NK cells that displayed heightened expression of T-bet and NKG2D and reduced expression of the exhaustion-associated co-inhibitory molecules PD-1 and TIM-3. Therefore, in ccRCC, the tumor microenvironment polarizes TAM toward an immunosuppressive profile that promotes tumor-infiltrating NK cell dysfunction, contributing to tumor progression. In addition, immunotherapy strategies targeting TAM may result in NK cell reinvigoration, thereby counteracting tumor progression.

Asunto(s)

Carcinoma de Células Renales , Interferón gamma , Neoplasias Renales , Células Asesinas Naturales , Macrófagos Asociados a Tumores , Células Asesinas Naturales/inmunología , Carcinoma de Células Renales/inmunología , Carcinoma de Células Renales/patología , Interferón gamma/metabolismo , Interferón gamma/inmunología , Humanos , Animales , Ratones , Neoplasias Renales/inmunología , Neoplasias Renales/patología , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Progresión de la Enfermedad , Línea Celular Tumoral , Microambiente Tumoral/inmunología , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/inmunología , Receptor de Muerte Celular Programada 1/metabolismo

RESUMEN

The thymus plays a crucial role in T cell differentiation, a complex process influenced by various factors such as antigens, the microenvironment and thymic architecture. The way the thymus resolves infections is critical, as chronic persistence of microbes or inflammatory mediators can obstruct the differentiation. Here, we illustrate that following inflammatory T helper 1 infectious processes like those caused by Candida albicans or Trypanosoma cruzi, single positive thymocytes adopt a mature phenotype. Further investigations focused on T. cruzi infection, reveal a substantial existence of CD44+ cells in both the cortical and medullary areas of the thymus at the onset of infection. This disturbance coincides with heightened interferon gamma (IFNγ) production by thymocytes and an increased cytotoxic capacity against T. cruzi-infected macrophages. Additionally, we observe a reduced exportation capacity in T. cruzi-infected mice. Some alterations can be reversed in IFNγ knockout mice (KO). Notably, the majority of these effects can be replicated by systemic expression of interleukin (IL)-12+IL-18, underlining the predominantly inflammatory rather than pathogen-specific nature of these phenomena. Understanding the mechanisms through which systemic inflammation disrupts normal T cell development, as well as subsequent T cell exportation to secondary lymphoid organs (SLO) is pivotal for comprehending susceptibility to diseases in different pathological scenarios.

Asunto(s)

Enfermedad de Chagas , Citocinas , Ratones Noqueados , Células TH1 , Timo , Trypanosoma cruzi , Animales , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/patología , Enfermedad de Chagas/metabolismo , Trypanosoma cruzi/inmunología , Ratones , Timo/inmunología , Timo/patología , Células TH1/inmunología , Citocinas/metabolismo , Interferón gamma/metabolismo , Interferón gamma/inmunología , Ratones Endogámicos C57BL , Inflamación/inmunología , Diferenciación Celular

RESUMEN

Studies about thymic B cells are scarce in the literature, but it was suggested that they can exert modulatory and regulatory functions on the immune system. Thymic B cells can play some role in regulating the most frequent allergic background worldwide, the atopy induced by the mite Dermatophagoides pteronyssinus (Der p). Here, we aimed to evaluate if the polyclonal IgG repertoire produced by Der p-atopic individuals can influence the homing and cytokine profile of human thymic B derived from non-atopic children aged less than seven days. With this purpose, we produced polyclonal IgG formulations and cultivated human thymocytes in their presence. We also assessed IgG subclasses and the direct interaction of IgG with thymic B cell membranes. Our results could demonstrate that Der p-atopic IgG could not reduce the expression of α4ß7 homing molecule as observed in response to the other IgG formulations and could reduce the frequency of IFN-γ- and IL-9-producing thymic B cells compared to the mock condition. Der p-atopic IgG could also induce thymic IL-10-producing B cells compared to control conditions. The IgG derived from Der p-atopic individuals failed to diminish the population of IL-13-producing thymic B cells, unlike the reduction observed with other IgG formulations when compared to the mock condition. All IgG formulations had similar levels of IgG subclasses and directly interacted with thymic B cell membranes. Finally, we performed experiments using peripheral non-atopic B cells where IgG effects were not observed. In conclusion, our observation demonstrates that IgG induced in allergic individuals can modulate non-atopic thymic B cells, potentially generating thymic B cells prone to allergy development, which seems to not occur in mature B cells.

Asunto(s)

Hipersensibilidad Inmediata , Hipersensibilidad , Animales , Niño , Humanos , Interleucina-10 , Dermatophagoides pteronyssinus , Interleucina-9 , Interferón gamma/metabolismo , Inmunoglobulina G , Fenotipo , Antígenos Dermatofagoides , Alérgenos

RESUMEN

Introduction: In VL, a proinflammatory phenotype is typically associated with enhanced phagocytosis and a Th1 mediated immune response resulting in infection control. In contrast, an anti-inflammatory phenotype, associated with a predominant regulatory response, typically enables intracellular multiplication of Leishmania parasites and disease progression. Methods: To investigate the impact of chemotherapy on Th2 and Th17 immune responses in patients with visceral leishmaniasis (VL), we assessed all combinations of intracellular expression of IFN-γ, IL-10, IL-4 and IL-17 in the CD4+ and CD8+ T cell populations of peripheral blood mononuclear cell (PBMC) samples from patients, after antigenic stimulation with Leishmania lysate, throughout treatment and follow-up. As increases in spleen and liver sizes and decreases in hematocrit, hemogloblin, erythrocytes, monocytes, leukocytes and platelets levels are strongly related to the disease, we studied the correlations between the frequencies of T cells producing the afore mentioned cytokines, individually and in combination, and these variables, as markers of disease or cure. Results: We found that the frequency of IFN-γ-producingCD4+ T cells increased until the end of chemotherapy with Glucantime® or AmBisome ®, while IL-10, IL-4 and IL-17-producing CD4+ T cells peaked on day 7 following the start of treatment. Although the frequency of CD4+IL-17+ cells decreased during treatment an increase was observed after clinical cure. The frequency of CD4+ T cells producing only IFN-γ or IL-17 correlated with blood monocytes levels. Frequencies of double-producers of IFN-γ and IL-10 or IL-4 correlated positively with eosinophils and platelets levels. Together, this suggest that IFN-γ drives the immune response towards Th1 at cure. In contrast, and associated with disease or Th2 response, the frequency of CD4+ IL-10+ cells correlated positively with spleen sizes and negatively with circulating monocyte levels, while the frequency of CD4+ producing both IL-4 and IL-10 correlated negatively with platelets levels. The frequency of CD8+ single-producers of IFN-γ increased from day 21 to 90 while that of single-producers of IL-10 peaked on day 7, of IL-4 on day 30 and of IL-17, on day 180. IFN-γ expression in CD8+ single- and double-producers of cytokines was indicative of an immune response associated with cure. In contrast, frequencies of CD8+ double-producers of IL-4 and IL-10, IL-4 and IL-17 and IL-10 and IL-17 and producers of three and four cytokines, were associated with disease and were low after the cure. Frequencies of CD8+ T cells producing IFN-γ alone or with IL-17 were positively correlated with platelets levels. In contrast, as markers of disease: 1) frequencies of single producers of IL-10 correlated negatively with leukocytes levels, 2) frequencies of double producers of IL-4 and IL-10 correlated negatively with platelet, leukocyte, lymphocyte and circulating monocyte levels, 3) frequencies of triple-producers of IFN-γ, IL-4 and IL-10 correlated negatively with platelet, leukocyte and neutrophil levels and 4) frequencies of producers of IFN-γ, IL-4, IL-10 and IL-17 simultaneously correlated positively with spleen size, and negatively with leukocyte and neutrophil levels. Discussion: Our results confirmed that the clinical improvement of VL patients correlates with the decrease of an IL-4 and IL-10 CD4+Th2 response, the recovery of CD4+ Th1 and Th17 responses and the frequency of CD8+ single-producers of IFN-γ and double producers of IFN-γ and IL-17.

Asunto(s)

Linfocitos T CD8-positivos , Leishmaniasis Visceral , Humanos , Interleucina-10 , Interleucina-17 , Leucocitos Mononucleares/metabolismo , Interleucina-4 , Interferón gamma/metabolismo , Citocinas/metabolismo , Células Th17/metabolismo

RESUMEN

BACKGROUND: Glioblastoma is a brain malignant tumor grade IV, highly invasive. Alterations in several signaling pathways are involved in glioblastoma development. In this work, we evaluated the IFN-γ canonical signaling pathway in glioblastoma cells and its effect on cell viability and migration. METHODS: The levels of STAT1/pSTAT1, IRF1, and PD-L1 in LN-18 glioblastoma cells were analyzed using western blotting. Cell viability was evaluated by calcein-AM/propidium iodide assays, and a wound healing assay was used to study the migration of glioblastoma cells treated with IFN-γ. Our aim was to determine the expression of IFN-γ signaling elements in cell lines and tissue from glioblastoma samples and examine the relationship between these elements and the survival of glioblastoma patients. The following platforms were utilized for analysis: the CCLE (Cancer Cell Line Encyclopedia), UALCAN (University of Alabama at Birmingham Cancer data analysis Portal), GEPIA (Gene Expression Profiling Interactive Analysis), and GENT2 (Gene Expression patterns across Normal and Tumor tissues). RESULTS: Our results evidenced that IFN-γ signaling increases non-phosphorylated and phosphorylated STAT1 levels and promotes the upregulation of IRF1 and PD-L1 in glioblastoma cells. The activation of IFN-γ signaling increased cell migration without affecting the viability of glioblastoma cells. Furthermore, in silico analysis showed that the elements of IFN-γ signaling pathways (IFNGR1/IFNGR2/STAT1/IRF1) are upregulated in human glioblastoma samples. The upregulation of IFN-γ signaling was associated with shorter survival in glioblastoma patients. CONCLUSION: IFN-γ signaling pathway is upregulated in glioblastoma, displaying pro-tumor activity. Thus, IFN-γ signaling elements may be potential biomarkers and targets for treating glioblastoma.

Asunto(s)

Glioblastoma , Interferón gamma , Humanos , Interferón gamma/metabolismo , Glioblastoma/genética , Antígeno B7-H1/metabolismo , Regulación hacia Arriba , Transducción de Señal , Línea Celular Tumoral

RESUMEN

In this study, we assessed the survival and immune response of mice vaccinated with recombinant Mycobacterium bovis BCG Pasteur that expressed the CP40 or CP09720 proteins after the mice were challenged with a C. pseudotuberculosis MIC-6 virulent strain. Six groups of mice (n = 10 mice per group) were immunised with a sterile 0.9% saline solution (G1), 106 CFU of M. bovis BCG Pasteur (G2), 106 CFU of M. bovis BCG/cp40 (G3), 106 CFU of M. bovis BCG/cp09720 (G4), M. bovis BCG/cp40 boosted with rCP40 (G5), and M. bovis BCG/cp09720 boosted with rCP09720 (G6). The highest survival rate of 90% was observed in the G5 group, followed by 80% in the G6 group and 70% in the G3 and G4 groups. Moreover, a significantly greater induction of IFN-γ and IL-10 was found in the G3 group and higher IL-17 levels were recorded in the G5 group compared to their levels in the control group (G1) (p < 0.05). A specific humoral immune response (total IgG) was found in the G5 and G6 groups on day 42 compared to the level of response in the G1 group. These results indicated that the vector vaccine elicited significantly greater survival of mice in all experimental groups after a strong virulent challenge and induced a strong immune response.

Asunto(s)

Corynebacterium pseudotuberculosis , Mycobacterium bovis , Animales , Ratones , Vacuna BCG , Interferón gamma/metabolismo

RESUMEN

Introduction: Tuberculosis (TB) is a bacterial infection caused by Mycobacterium tuberculosis (M.tb). B cells are the central mediator of the humoral response; they are responsible for producing antibodies in addition to mediating other functions. The role of the cellular response during the TB spectrum by B cells is still controversial. Methods: In this study, we evaluated the distribution of the circulating B cell subsets in patients with active and latent TB (ATB and LTB, respectively) and how they respond to stimuli of protein or lipid from M.tb. Results: Here, we show that ATB patients show an immune fingerprinting. However, patients with drug-sensitive- (DS-TB) or drug-resistant- (DR-TB) TB have altered frequencies of circulating B cells. DS-TB and DR-TB display a unique profile characterized by high systemic levels of IFN-γ, IL-10, IgG, IgG/IgM ratio, and total B cells. Moreover, B cells from DR-TB are less efficient in producing IL-10, and both DS-TB and DR-TB produce less IFN-γ in response to M.tb antigens. Conclusion: These results provide new insights into the population dynamics of the cellular immune response by B cells against M.tb and suggest a fingerprinting to characterize the B-cell response on DR-TB.

Asunto(s)

Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis , Humanos , Interleucina-10 , Interferón gamma/metabolismo , Inmunoglobulina G