Tumor cell lysate with low content of HMGB1 enhances immune response of dendritic cells against lung cancer in mice / 南方医科大学学报

OBJECTIVE@#To assess the effect of tumor cell lysate (TCL) with low high-mobility group B1 (HMGB1) content for enhancing immune responses of dendritic cells (DCs) against lung cancer.@*METHODS@#TCLs with low HMGB1 content (LH-TCL) and normal HMGB1 content (NH-TCL) were prepared using Lewis lung cancer (LLC) cells in which HMGB1 was inhibited with 30 nmol/L glycyrrhizic acid (GA) and using LLC cells without GA treatment, respectively. Cultured mouse DCs were exposed to different doses of NH-TCL and LH-TCL, using PBS as the control. Flow cytometry was used to detect the expressions of CD11b, CD11c and CD86 and apoptosis of the stimulated DCs, and IL-12 levels in the cell cultures were detected by ELISA. Mouse spleen cells were co-cultured with the stimulated DCs, and the activation of the spleen cells was assessed by detecting CD69 expression using flow cytometry; TNF-β production in the spleen cells was detected with ELISA. The spleen cells were then co-cultured with LLC cells at the effector: target ratios of 5:1, 10:1 and 20:1 to observe the tumor cell killing. In the animal experiment, C57/BL6 mouse models bearing subcutaneous LLC xenograft received multiple injections with the stimulated DCs, and the tumor growth was observed.@*RESULTS@#The content of HMGB1 in the TCL prepared using GA-treated LLC cells was significantly reduced (P < 0.01). Compared with NH-TCL, LH-TCL showed a stronger ability to reduce apoptosis (P < 0.001) and promote activation and IL- 12 production in the DCs. Compared with those with NH-TCL stimulation, the DCs stimulated with LH-TCL more effectively induced activation of splenic lymphocytes and enhanced their anti-tumor immunity (P < 0.05). In the cell co-cultures, the spleen lymphocytes activated by LH-TCL-stimulated DCs showed significantly enhanced LLC cell killing activity (P < 0.01). In the tumor-bearing mice, injections of LH-TCL-stimulated DCs effectively activated host anti-tumor immunity and inhibited the growth of the tumor xenografts (P < 0.05).@*CONCLUSION@#Stimulation of the DCs with LH-TCL enhances the anti-tumor immune activity of the DCs and improve the efficacy of DCbased immunotherapy for LLC in mice.

Aspects of Langerhans cells and TNF-α in the cutaneous immunity of anogenital warts

Abstract Background: Anogenital warts are the leading sexually transmitted infection in patients seeking care at specialized clinics. They may display a vast array of forms, according to the interaction of the virus with the host's immunity. Cellular immunity is the epithelium's main form of defense against the virus, involving an active participation of the Langerhans cells and pro-inflammatory cytokines such as TNF-α. Objective: To assess the epithelial immune response of anogenital warts in males, according to the number of lesions presented. Methods: This is a prospective, cross-sectional study carried out at the dermatology outpatient clinic in a tertiary hospital. We included male patients over 18 years of age without comorbidities who had anogenital condylomata and no previous treatments.In order to evaluate the local epithelial immunity, the lesions were quantified, then removed and employed in CD1a immunohistochemistry assays for assessing the morphometry and morphology of Langerhans cells; TNF-α; reaction was used for determining cytokine positivity in the epithelium. Results: 48 patients were included in the study. There was no statistically significant difference as to the number of Langerhans cells, in their morphology, or the presence of TNF-α. However, patients presenting with more Langerhans cells in the lesions had cells with a star-like and dendritic morphology, whereas in those with a lower cell count had cells with a rounded morphology and no dendrites (p < 0.001). Study limitations: Small number of patients analyzed. Conclusion: There was no difference in epithelial immunity between patients having few or many anogenital condyloma lesions as measured by the morphology and morphometry of Langerhans cells and TNF-α; positivity. Such an assessment employing immunity markers differing from the usual ones is expected to yield useful results.

LMP2-DC Vaccine Elicits Specific EBV-LMP2 Response to Effectively Improve Immunotherapy in Patients with Nasopharyngeal Cancer / 生物医学与环境科学（英文）

Objective@#To evaluate the safety and effectiveness of a vaccine based on latent membrane protein 2 (LMP2) modified dendritic cells (DCs) that boosts specific responses of cytotoxic T lymphocytes (CTLs) to LMP2 before and after intradermal injection in patients with nasopharyngeal carcinoma (NPC).@*Methods@#DCs were derived from peripheral blood monocytes of patients with NPC. We prepared LMP2-DCs infected by recombinant adenovirus vector expressing LMP2 (rAd-LMP2). NPC patients were immunized with 2 × 10 @*Results@#We demonstrated that DCs derived from monocytes displayed typical DC morphologies; the expression of LMP2 in the LMP2-DCs vaccine was confirmed by immunocytochemical assay. Twenty-nine patients with NPC were enrolled in this clinical trial. The LMP2-DCs vaccine was well tolerated in all of the patients. Boosted responses to LMP2 peptide sub-pools were observed in 18 of the 29 patients with NPC. The follow-up data of 29 immunized patients from April, 2010 to April 2015 indicated a five-year survival rate of 94.4% in responders and 45.5% in non-responders.@*Conclusion@#In this pilot study, we demonstrated that the LMP2-DCs vaccine is safe and effective in patients with NPC. Specific CTLs responses to LMP2 play a certain role in controlling and preventing the recurrence and metastasis of NPC, which warrants further clinical testing.

Las células dendríticas plasmacitoides evocan la respuesta efectora de los linfocitos T citotóxicos específicos para Salmonella / The plasmacytoid dendritic cells evoke Salmonella-specific CTL effector response

Resumen Introducción. La función inmunológica de las células dendríticas plasmacitoides durante las infecciones bacterianas, como la de Salmonella spp., es poco conocida. En ese contexto, se analizó su función efectora para presentar antígenos de Salmonella Typhimurium ante linfocitos T citotóxicos. Objetivo. Analizar la respuesta de los linfocitos T citotóxicos específicos para Salmonella evocada por las células dendríticas plasmacitoides. Materiales y métodos. Se usaron células dendríticas plasmacitoides marcadas con éster de succinimidil-carboxifluoresceína, pulsadas con el epítopo de Salmonella OmpC73 Kb- restringido o infectadas con S. Typhimurium como blanco en ensayos de citotoxicidad. Resultados. La lisis específica tuvo significación estadística usando células dendríticas plasmacitoides positivas pulsadas con OmpC73 en todas las relaciones de células efectoras y blanco (E:B) (p≤0,05); en cuanto a las células dendríticas plasmacitoides positivas para S. Typhimurium, solo se observó significación estadística en la relación de 1:100 (p≤0,05) usando las células efectoras OmpC73. Conclusión. Las células dendríticas plasmacitoides pueden evocar la respuesta de los linfocitos T citotóxicos durante la infección con S. Typhimurium.

Abstract Introduction: The immunological role of plasmacytoid dendritic cells (pDC) in bacterial infections such as Salmonella has been poorly documented. Therefore, we analyzed the effector function of these cells by presenting cytotoxic T lymphocytes (CTL) with Salmonella Typhimurium antigens. Objective: To analyze the Salmonella-specific CTL response evoked by pDCs. Materials and methods: We used plasmacytoid dendritic cells stained with carboxyfluorescein succinimidyl ester (CFSE) and pulsed with OmpC73, Salmonella Kb- restricted epitopes or S. Typhimurium as targets for cytotoxicity assays. Results: Specific lysis was shown to be statistically significant in pDC + OmpC73 for all effector:target ratios (p≤0.05). For pDC + S. Typhimurium, statistical significance was only observed at a 1:100 ratio (p≤0.05) using OmpC73. Conclusion: Plasmacytoid dendritic cells evoke CTL response during S. Typhimurium infection.

Smoking promotes exacerbated inflammatory features in dendritic cells of Chilean rheumatoid arthritis patients / El tabaco exacerba características inflamatorias en células dendríticas de pacientes chilenos con artritis reumatoide

ABSTRACT Background: The dual potential to promote tolerance or inflammation when facing self-antigens makes dendritic cells (DCs) fundamental players in autoimmunity. There is an association between smoking and DCs maturation in patients with rheumatoid arthritis (RA). However, ethnicity is a key factor in autoimmune disorders. Aim: To evaluate phenotypic and functional alterations of DCs obtained from Chilean patients with RA as compared to healthy controls (HC). In second term, to compare the inflammatory behaviour of DCs between smoker and non-smoker patients. Material and Methods: Monocyte-derived DCs and T-cells were obtained from blood samples isolated from 30 HC and 32 RA-patients, 14 of which were currently smokers and 18 non-smokers. Several maturation surface markers were evaluated in DCs, including HLA-DR, CD40, CD80, CD83 and CD86. Furthermore, autologous co-cultures of DCs and T-cells were carried out and then T-cell proliferation, and expansion of Th1, Th17 and Tregs were analysed. Results: Compared with HC, RA-patients displayed increased HLA-DR expression in DCs, which was manifested mainly in patients with moderate-to- high disease activity scores (DAS28). Furthermore, RA-patients presented a stronger Th17-expansion and a correlation between DAS28 and Th1-expansion. Both effects were mainly observed in patients in remission or with a low DAS28. Moreover, smoker RA-patients displayed enhanced HLA-DR and CD83 expression in DCs as well as an exacerbated Th17-expansion and a correlation between DAS28 and Th1-expansion. Conclusions: These findings suggest that smoking enhances the inflammatory behaviour of DCs and the consequent Th1 and Th17-mediated response in patients with RA

Introducción: El potencial dual que poseen para promover tolerancia o inflamación ante antígenos propios, hace de las células dendríticas (CDs) actores fundamentales en el desarrollo de autoinmunidad. Existe una asociación entre fumar y la maduración de las CDs en pacientes con artritis reumatoide (AR). No obstante, la etnicidad es un factor clave a considerar en desórdenes autoinmunes. Objetivos: Comparar las alteraciones fenotípicas y funcionales de las CDs obtenidas desde pacientes Chilenos con AR y controles sanos (CS). Además, analizamos las diferencias en el comportamiento inflamatorio que existe entre las CDs obtenidas de pacientes fumadores y CS. Materiales y Métodos: Se obtuvieron CDs derivadas de monocitos y células T desde muestras de sangre aisladas de 30 CS y 32 pacientes con AR, 14 de los cuales eran fumadores y 18 no fumadores. Se evaluaron marcadores de maduración en la superficie de las CDs: HLA-DR, CD40, CD80, CD83 y CD86. Además, se realizaron co-cultivos autólogos de células T y CDs, analizando la proliferación de células T, y la expansión de células Th1, Th17 y Tregs. Resultados: En comparación con los CS, los pacientes AR mostraron un aumento de la expresión de HLA-DR en las CDs, principalmente en los individuos con DAS28 moderado-alto. Los pacientes con AR presentaron una mayor expansión de células Th17 y una correlación entre el DAS28 y la expansión de células Th1, ambos efectos manifestados principalmente en los individuos con un DAS28 bajo o en remisión. Además, los pacientes con AR fumadores mostraron un aumento en la expresión de HLA-DR y CD83 en las CDs y una expansión de células Th17 exacerbada así como una correlación entre el DAS28 y la expansión de células Th1. Conclusiones: Nuestros resultados sugieren que fumar favorece el comportamiento inflamatorio de las CDs y en consecuencia la inducción de respuestas mediadas por células Th1 y Th17 en los pacientes Chilenos con AR.

Dendritic cells and their relation to apical peridontitis

Abstract: The purpose of this manuscript was to re-discuss apical periodontitis, apical biofilm, and its possible relationship with dendritic cells (DC). DCs are potent regulators of the immune system and their function is divided into three categories that involve the presentation of antigens: the presentation of antigens and activation of T cells; a not well established category suggested that DCs induce and maintain immunological tolerance; and the maintenance of the immune memory in conjunction with B cells. DCs in periapical inflammatory lesions are composed of at least two subpopulations that can be distinguished on the basis of ultrastructure and phenotype. These populations might differ in lineage, state of maturation, differentiation, activation, and/or function. The authors hereby analyzed the root apexes of teeth under SEM, after performing apicoectomy due to the failure of conventional endodontic treatment. Microbial biofilm with multispecies and areas of resorption with the presence of Howship lacunae, and images suggestive of denditric cells could be observed. The presence of DCs in periapical lesion could be an indication of the severity of the lesion, with a constant presence of antigen in the periradicular region.

Generation of potent cytotoxic T lymphocytes against in male patients with non-muscle invasive bladder cancer by dendritic cells loaded with dying T24 bladder cancer cells

ABSTRACT Background In order to induce a potent cytotoxic T lymphocyte (CTL) response in dendritic cell (DC)-based immunotherapy for bladder cancer, various tumor antigens can be loaded onto DCs. Objective The aim of this study was to establish a method of immunotherapy for male patients with non-muscle invasive bladder cancer (NMIBC), using bladder cancer-specific CTLs generated in vitro by DCs. Materials and Methods Monocyte-derived DCs from bladder cancer patients were induced to mature in a standard cytokine cocktail (IL-1β, TNF-α, IL-6, and PGE2: standard DCs, sDCs) or anα-type 1-polarized DC (αDC1) cocktail (IL-1β, TNF-α, IFN-α, IFN-γ, and polyinosinic:polycytidylic acid) and loaded with the UVB-irradiated bladder cancer cell line, T24. Antigen-loaded αDC1s were evaluated by morphological and functional assays, and the bladder cancer-specific CTL response was analyzed by cytotoxic assay. Results The αDC1s significantly increased the expression of several molecules pertaining to DC maturation, regardless of whether or not the αDC1s were loaded with tumor antigens, relative to sDCs. The αDC1s demonstrated increased production of interleukin-12 both during maturation and after subsequent stimulation with CD40L that was not significantly affected by loading with tumor antigens as compared to that of sDCs. Bladder cancer-specific CTLs targeting autologous bladder cancer cells were successfully induced by αDC1s loaded with dying T24 cells. Conclusion Autologous αDC1s loaded with an allogeneic bladder cancer cell line resulted in increased bladder cancer-specific CTL responses as compared to that with sDCs, and therefore, may provide a novel source of DC-based vaccines that canbe used in immunotherapy for male patients with NMIBC.

Papel de las células dendríticas en la infección por el virus dengue: blancos de replicación y respuesta inmune / Role of dendritic cells in infection by dengue virus: targets for replication and immune response

Dengue fever, caused by dengue virus (DENV) infection, is one of the most important diseases in the world, not only due to the high morbidity/mortality rates it causes, but also because of its great economic and social impact in tropical/subtropical countries. DENV infection has a wide range of clinical manifestations ranging from asymptomatic infection or infection with mild symptoms to severe dengue that can lead to death. At present, no etiological treatment or effective globally distributed vaccine against the four DENV serotypes exists. Despite great efforts made to understand the mechanism associated with DENV disease pathogenesis the causes leading to severe dengue presentation have not been clarified. Some hypotheses seek to give a biological and physiological explanation to the clinical manifestations that appear during the infection. Based on the evidence that after contact with dendritic cells DENV alters the functionality of these cells, this review aims to describe the most relevant findings regarding the importance of dendritic cells in the context of DENV infection and progression of the illness.

El dengue, causada por el virus dengue (DENV), es una de las enfermedades más importantes no sólo por los altos índices de morbilidad/mortalidad, sino también por su gran impacto económico y social en los países de las regiones tropicales/subtropicales. La infección por el DENV cursa por un variado rango de manifestaciones clínicas que van desde una infección asintomática o con síntomas leves, hasta el dengue grave que puede ser fatal. En la actualidad, no se dispone de un tratamiento etiológico y tampoco de una vacuna eficaz mundialmente distribuida, contra los 4 serotipos del DENV. A pesar de los grandes esfuerzos orientados a entender el mecanismo asociado con la patogénesis de la enfermedad, aún no se ha logrado esclarecer de forma definitiva las causas que conllevan a las formas graves de enfermedad. Algunas hipótesis buscan dar una explicación biológica y fisiológica a las manifestaciones clínicas que se presentan durante la infección. Dado que una de ellas sugiere que luego del contacto con las células dendríticas el DENV altera su funcionalidad, la presente revisión tiene como objetivo describir los hallazgos más relevantes referentes a la importancia de dichas células en el marco de la infección por el DENV y progresión de la enfermedad.

Vacunas terapéuticas antitumorales basadas en células dendríticas / Dendritic cell-based therapeutic cancer vaccines

En los últimos años la inmunoterapia ha revolucionado el tratamiento de pacientes con cáncer avanzado. El mayor conocimiento de la biología tumoral y de la inmunología ha permitido desarrollar tratamientos racionales manipulando el sistema inmunitario con importante impacto clínico. Entre otras estrategias de inmunoterapia contra el cáncer se ha explorado el uso de vacunas terapéuticas basadas en células dendríticas (CD). Las CD son células de origen hematopoyético, que expresan constitutivamente moléculas presentadoras de antígeno, y son funcionalmente las inductoras más potentes de la activación y proliferación de linfocitos T a los que presentan antígenos. Los linfocitos T CD8+ proliferan y adquieren capacidad citotóxica cuando reconocen su antígeno específico presentado en la superficie de CD, aunque solo algunos tipos de CD pueden presentar antígenos internalizados desde el exterior celular a precursores de linfocitos T citotóxicos (a esta función se la llama presentación cruzada). Explotar la inducción de una respuesta inmunitaria adaptativa eficaz se considera una buena opción por su especificidad y prolongada duración de la respuesta. Las CD, gracias a su particular capacidad de presentación antigénica y de estimulación linfocitaria, son capaces de revertir la respuesta inmunitaria antitumoral deficiente que presentan algunos pacientes con cáncer. Las CD se pueden obtener a partir de distintas fuentes, empleando diversos protocolos para generar diferenciación y maduración, y se administran por diversas vías como son subcutánea, intravenosa o intranodal. La gran variedad de protocolos en los que se aplican las CD explica los resultados clínicos tan heterogéneos que se han comunicado hasta la fecha.

In recent years immunotherapy has revolutionized the treatment of patients with advanced cancer. The increased knowledge in the tumor immune-biology has allowed developing rational treatments by manipulation of the immune system with significant clinical impact. This rapid development has significantly changed the prognosis of many tumors without treatment options up to date. Other strategies have explored the use of therapeutic vaccines based on dendritic cells (DC) by inducing antitumor immunity. DC are cells of hematopoietic origin, constitutively expressing molecules capable to present antigens, that are functionally the most potent inducers of the activation and proliferation of antigen specific T lymphocytes. The CD8+ T cells proliferate and acquire cytotoxic capacity after recognizing their specific antigen presented on the surface of DC, although only some types of DC can present antigens internalized from outside the cell to precursors of cytotoxic T lymphocytes (this function is called cross-presentation) requiring translocation mechanisms of complex antigens. The induction of an effective adaptive immune response is considered a good option given its specificity, and prolonged duration of response. The DC, thanks to its particular ability of antigen presentation and lymphocyte stimulation, are able to reverse the poor antitumor immune response experienced by patients with cancer. The DC can be obtained from various sources, using different protocols to generate differentiation and maturation, and are administered by various routes such as subcutaneous, intravenous or intranodal. The wide variety of protocols resulted in heterogeneous clinical responses.

Rol de la microbiota gastrointestinal en la regulación de la respuesta inmune / The role of gut microbiota in the regulation of the immune response

The gastrointestinal tract hosts around 10(14) bacterial microorganisms, in a constantly growing density from the stomach to the distal colon. This microbiota is composed by more than 500 species of bacteria, which are quickly acquired after birth, fairly stable during the host’s life, and essential for human homeostasis. These bacteria have important functions, such as stimulating the immune system, protecting the host from invading bacteria and viruses, and improving digestion, especially of complex carbohydrates. Also, the gut microbiota interacts directly with the immune system. However, the interaction of the intestinal epithelium and its microbiota with the immune system has yet to be fully understood. Secretory immunoglobulin A, produced by the plasma cells in Peyer’s patches and in the lamina propria, maintains non-invasive commensal bacteria and neutralize invasive pathogens. Dendritic cells migrate from the lamina propria of the secondary lymphoid organs to regulate gut immunity. They also have a key role maintaining luminal IgA and inducing the growth of regulatory T cells. Dendritic cells supervise the gut microenvironment too, keeping an immunological equilibrium and tolerance. The importance of the gut microbiota in regulating the immune system lies mostly in the homeostasis-or positive equilibrium. Thus, many diseases are a consequence of poor interactions or a loss of this equilibrium.

Immunotherapy for human papillomavirus-associated disease and cervical cancer: review of clinical and translational research / 부인종양

Cervical cancer is the fourth most lethal women's cancer worldwide. Current treatments against cervical cancer include surgery, radiotherapy, chemotherapy, and anti-angiogenic agents. However, despite the various treatments utilized for the treatment of cervical cancer, its disease burden remains a global issue. Persistent infection of human papillomavirus (HPV) has been identified as an essential step of pathogenesis of cervical cancer and many other cancers, and nation-wide HPV screening as well as preventative HPV vaccination program have been introduced globally. However, even though the commercially available prophylactic HPV vaccines, Gardasil (Merck) and Cervarix (GlaxoSmithKline), are effective in blocking the entry of HPV into the epithelium of cervix through generation of HPV-specific neutralizing antibodies, they cannot eliminate the pre-existing HPV infection. For these reason, other immunotherapeutic options against HPV-associated diseases, including therapeutic vaccines, have been continuously explored. Therapeutic HPV vaccines enhance cell-mediated immunity targeting HPV E6 and E7 antigens by modulating primarily dendritic cells and cytotoxic T lymphocyte. Our review will cover various therapeutic vaccines in development for the treatment of HPV-associated lesions and cancers. Furthermore, we will discuss the potential of immune checkpoint inhibitors that have recently been adopted and tested for their treatment efficacy against HPV-induced cervical cancer.

Differential expression of CC chemokines (CCLs) and receptors (CCRs) by human T lymphocytes in response to different Aggregatibacter actinomycetemcomitans serotypes

In Aggregatibacter actinomycetemcomitans, different serotypes have been described based on LPS antigenicity. Recently, our research group has reported a differential immunogenicity when T lymphocytes were stimulated with these different serotypes. In particular, it was demonstrated that the serotype b of A. actinomycetemcomitans has a stronger capacity to trigger Th1- and Th17-type cytokine production.Objective This study aimed to quantify the expression of different CC chemokines (CCLs) and receptors (CCRs) in T lymphocytes stimulated with the differentA. actinomycetemcomitans serotypes. In addition, the expression of the transcription factors T-bet, GATA-3, RORC2, and Foxp3, master-switch genes implied in the Th1, Th2, Th17, and T-regulatory differentiation, respectively, was analysed in order to determine T-cell phenotype-specific patterns of CCL and CCR expression upon A. actinomycetemcomitans stimulation.Material and Methods Human naïve CD4+ T lymphocytes were obtained from healthy subjects and stimulated with autologous dendritic cells primed with the differentA. actinomycetemcomitans serotypes. The expression levels for the chemokines CCL1, CCL2, CCL3, CCL5, CCL11, CCL17, CCL20, CCL21, CCL25, and CCL28, as well as the chemokine receptors CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 were quantified by qPCR. Similarly, the expression levels for the transcription factors T-bet, GATA-3, RORC2, and Foxp3 were quantified and correlated with the CCL and CCR expression levels.Results Higher expression levels of CCL2, CCL3, CCL5, CCL20, CCL21, CCL28, CCR1, CCR2, CCR5, CCR6, CCR7, and CCR9 were detected in T lymphocytes stimulated with the serotype b of A. actinomycetemcomitans compared with the other serotypes. In addition, these higher expression levels of CCLs and CCRs positively correlated with the increased levels of T-bet and RORC2 when T lymphocytes were stimulated with the serotype b.Conclusion A T-lymphocyte response biased towards a Th1- and Th17-pattern of CCL and CCR expression was detected under stimulation with the serotype b ofA. actinomycetemcomitans.

Inmunoterapia en melanoma: vacunas de células dendríticas / Melanoma immunotherapy: dendritic cell vaccines

La presente es una revisión narrativa que muestra la información accesible a la comunidad científica sobre melanoma e inmunoterapia. Las células dendríticas tienen la capacidad de participar en la inmunidad innata y adaptativa, pero no son ajenas a la evasión inmune de los tumores. Conocer su biología y rol ha llevado a generar in vitro varios prospectos de vacunas celulares autólogas contra diversos tipos de cáncer en humanos y modelos animales; sin embargo, en vista de la poca eficiencia que han mostrado, se deben implementar estrategias para potenciar su capacidad natural ya sea a través de la coexpresión de moléculas clave para activar o reactivar al sistema inmune, en combinación con biosimilares o drogas quimioterapeúticas y no se debe descartar la acción de productos naturales como alternativa inmunoestimulante o adyuvante. Todos los tipos de inmunoterapía deberían medir el impacto de las células supresoras de origen mieloide, las que pueden atacar al sistema inmune y ayudar a la progresión tumoral, respectivamente. Esto puede reducir la actividad de las vacunas celulares y/o sus combinaciones pudiendo ser la diferencia entre el éxito o no de la inmunoterapia. Aunque en melanoma existen biosimilares aprobados por la Food and Drug Administration (FDA) no todos tienen el éxito esperado por lo que es necesario evaluar otras estrategias que incluyan vacunas celulares cargadas con péptidos antigénicos tumorales expresados exclusivamente o antígenos provenientes de extractos tumorales y sus respectivos adyuvantes...

This is a narrative review that shows accessible information to the scientific community about melanoma and immunotherapy. Dendritic cells have the ability to participate in innate and adaptive immunity, but are not unfamiliar to the immune evasion of tumors. Knowing the biology and role has led to generate in vitro several prospects of autologous cell vaccines against diverse types of cancer in humans and animal models. However, given the low efficiency they have shown, we must implement strategies to enhance their natural capacity either through the coexpression of key molecules to activate or reactivate the immune system, in combination with biosimilars or chemotherapeutic drugs. The action of natural products as alternative or adjuvant immunostimulant should not be ruled out. All types of immunotherapy should measure the impact of myeloid suppressor cells, which can attack the immune system and help tumor progression, respectively. This can reduce the activity of cellular vaccines and/or their combinations, that could be the difference between success or not of the immunotherapy. Although for melanoma there exist biosimilars approved by the Food and Drug Administration (FDA), not all have the expected success. Therefore it is necessary to evaluate other strategies including cellular vaccines loaded with tumor antigenic peptides expressed exclusively or antigens from tumor extracts and their respective adjuvants...

Activation and cytokine profile of monocyte derived dendritic cells in leprosy: in vitro stimulation by sonicated Mycobacterium leprae induces decreased level of IL-12p70 in lepromatous leprosy

Dendritic cells (DCs) play a pivotal role in the connection of innate and adaptive immunity of hosts to mycobacterial infection. Studies on the interaction of monocyte-derived DCs (MO-DCs) using Mycobacterium leprae in leprosy patients are rare. The present study demonstrated that the differentiation of MOs to DCs was similar in all forms of leprosy compared to normal healthy individuals. In vitro stimulation of immature MO-DCs with sonicated M. leprae induced variable degrees of DC maturation as determined by the increased expression of HLA-DR, CD40, CD80 and CD86, but not CD83, in all studied groups. The production of different cytokines by the MO-DCs appeared similar in all of the studied groups under similar conditions. However, the production of interleukin (IL)-12p70 by MO-DCs from lepromatous (LL) leprosy patients after in vitro stimulation with M. lepraewas lower than tuberculoid leprosy patients and healthy individuals, even after CD40 ligation with CD40 ligand-transfected cells. The present cumulative findings suggest that the MO-DCs of LL patients are generally a weak producer of IL-12p70 despite the moderate activating properties ofM. leprae. These results may explain the poor M. leprae-specific cell-mediated immunity in the LL type of leprosy.

Acesso a informações sobre como evitar problemas bucais entre escolares da Rede Pública de Ensino / Access to information about how to prevent oral problems among school children in the public school network

O presente estudo propõe-se a identificar a prevalência do acesso a informações sobre como evitar problemas bucais entre escolares da rede pública de ensino, assim como os fatores associados a este acesso. Trata-se de um estudo transversal e analítico conduzido entre escolares de 12 anos de idade de um município brasileiro de grande porte populacional. Os exames foram realizados por 24 cirurgiões-dentistas treinados e calibrados com auxilio de 24 anotadores. A coleta de dados ocorreu em 36 escolas sorteadas das 89 escolas públicas do município. Foram conduzidas análises descritivas, univariadas e múltiplas. Dos 2510 escolares incluídos no estudo, 2211 relataram já ter recebido informações sobre como evitar problemas bucais. O acesso a tais informações foi maior entre os que utilizaram serviços odontológicos privado/convênio; e menor entre aqueles que utilizaram o serviço para tratamento, os que avaliaram o serviço como regular ou ruim/péssimo, os que utilizam como meio de higiene bucal somente escova dente/escova dente e higienização a língua e os que relataram não estarem satisfeitos com a aparência de seus dentes. Conclui-se que a maioria dos escolares teve acesso a informações sobre como evitar problemas bucais, o qual esteve associado a características dos serviços de saúde, comportamentos e desfechos de saúde.

The scope of this study is to identify the prevalence of access to information about how to prevent oral problems among schoolchildren in the public school network, as well as the factors associated with such access. This is a cross-sectional and analytical study conducted among 12-year-old schoolchildren in a Brazilian municipality with a large population. The examinations were performed by 24 trained dentists and calibrated with the aid of 24 recorders. Data collection occurred in 36 public schools selected from the 89 public schools of the city. Descriptive, univariate and multiple analyses were conducted. Of the 2510 schoolchildren included in the study, 2211 reported having received information about how to prevent oral problems. Access to such information was greater among those who used private dental services; and lower among those who used the service for treatment, who evaluated the service as regular or bad/awful. The latter use toothbrush only or toothbrush and tongue scrubbing as a means of oral hygiene and who reported not being satisfied with the appearance of their teeth. The conclusion drawn is that the majority of schoolchildren had access to information about how to prevent oral problems, though access was associated with the characteristics of health services, health behavior and outcomes.

Estudo da interação entre neutrófilos, células dendríticas humanas e L. braziliensis / Study of the interaction between neutrophils, human dendritic cells and L. braziliensis

Os neutrófilos são essenciais para a resposta imune inata contra uma variedade de patógenos. Eles são capazes de modular a resposta imune através da produção de citocinas e quimiocinas, degranulação e a sua interação direta com outras células no local da infecção, tais como as células dendríticas. A interação entre as células do sistema imune inato é essencial para direcionar a resposta imune adaptativa, a qual é responsável pela eliminação de microrganismos e manutenção de memória imunológica. Objetivo: Este estudo avaliou a interação de neutrófilos humanos com Leishmania braziliensis, através da análise da expressão de moléculas de superfície, liberação de enzimas presentes nos grânulos e produção de espécies reativas de oxigênio (ROS). Também foi avaliada a interação entre neutrófilos humanos infectados e células dendríticas, a fim de se observar o efeito desta interação na indução da ativação das células dendríticas. Metodologia: Os neutrófilos foram purificados a partir do sangue periférico de doadores saudáveis e as células dendríticas foram geradas in vitro. Os neutrófilos foram infectados ou não com L. braziliensis e co-cultivados com as células dendríticas. Em seguida, os sobrenadantes e as células foram coletadas para avaliar a liberação de enzimas, tais como mieloperoxidase (MPO) e metaloproteinase 9 (MMP-9). O fenótipo e a função dos neutrófilos foram analisados através da expressão de Mac-1 (CD18 e CD11b), CD16, CD62-L e produção de ROS...

Neutrophils are essential in the innate immune response against a variety of pathogens. They are able to modulate immune response by cytokine and chemokine production, release of granules and their direct interaction with other cells at the infection site. Dendritic cells are recruited in response to cytokines and chemokines produced by neutrophils. The interaction between cells of the innate immune system is essential for targeting the adaptive immune response, which is responsible for eliminating microorganisms and the maintenance of immunological memory. Objective: Evaluate the interaction of human neutrophils with Leishmania braziliensis, through the analysis of surface molecule expression, release of granules enzymes and production of reactive oxygen species (ROS). We also evaluated the interaction between human infected neutrophils and dendritic cells, in order to observe the effect of this interaction on dendritic cells. Methodology: Neutrophils were purified from peripheral blood of healthy donors and dendritic cells were generated in vitro. Neutrophils were infected or not with L. braziliensis and cocultured with DC. Afterwards, supernatants and cells were harvested to evaluate the release of granules enzymes, such as myeloperoxidase (MPO) and metalloproteinase 9 (MMP-9). Neutrophils phenotype and function were analyzed by the expression of Mac-1 (CD18 and CD11b), CD16 and ROS production...

Dendritic cell vaccine treatment of advanced de novo colorectal cancer in renal transplant patients.

Objective: The clinical outcome, especial the immunologic responses to cancer and graft, of dendritic cell (DC) vaccine in the treatment of advanced de novo colorectal cancer (CRC) in renal transplant patients was investigated in this study. Materials and Methods: 7 patients were received 1 cycle tumor lysate pulsed autologous DC vaccine. The positive cell-mediated cytotoxicity responses to DC vaccine against CRC cell in two out of 7 patients were seen by delayed type hypersensitivity (DTH) test. The positive cell-mediated cytotoxicity responses to DC vaccine against normal kidney cell in all 7 patients were not seen by DTH tests and no notable change of renal function during and after vaccination. Conclusions: DC vaccine has emerged as a promising new strategy in the treatment of advanced de novo CRC in renal transplant patients and DC vaccines have become an attractive therapeutic option, developing immune responses specific against CRC cell, achieving clinical efficacy without graft failure.

Oral chronic graft-versus-host disease: analysis of dendritic cells subpopulations

The graft-versus-host disease is the major cause of morbidity and mortality in patients who have undergone hematopoietic stem cell transplantation. Aiming at contributing to the understanding of the role of myeloid and plasmacytoid dendritic cells, and natural killer cells in chronic graft-versus-host disease, we examined biopsies of jugal mucosa of 26 patients with acute myeloid leukemia who had undergone allogenic hematopoietic stem cell transplantation. Half of these patients developed oral chronic graft-versus-host disease. Microscopic sections were immunohistochemically stained for anti-CD1a, anti-CD123 and anti-CD56. We calculated the number of immunostained cells in the corium per square millimeter and applied the Mann-Whitney test. Results showed a statistically significant increase of myeloid dendritic cells (CD1a+; p=0,02) and natural killer cells (CD56; p=0,04) in patients with oral chronic graft-versus-host disease. CD123 immunostaining showed no statistical difference between groups. It was concluded that myeloid dendritic cells and natural killer cells participate in the development of oral chronic graft-versus-host disease.

Redução da inflamação das vias aéreas e da produção de anticorpos IgEatravés do uso de células dendríticas tolerogênicas pulsadas com extrato solúvel de Blomia tropicalis / Reduction in airway inflammation and the production of IgE antibodies through the use of tolerogenic dendritic cells pulsed with soluble extracts of Blomia tropicalis

As alergias afetam cerca de 20 a 30% da população mundial e sua prevalência, bem como a gravidade dos sintomas, tem aumentado nas últimas décadas. As terapias existentes para as desordens do trato respiratório ocorrem por períodos prolongados, apresentam efeitos colaterais, muitas vezes não são efetivas para pacientes graves e dependem do afastamento do alérgeno. Uma alternativa para esses pacientes seria a indução de tolerância imunológica, através da terapia celular com células dendríticas pulsadas com o alérgeno. O presente trabalho objetivou avaliar o efeito de células dendríticas mielóides sensibilizadas in vitro com extrato de B. tropicalis em modelo murino de alergia respiratória. Em modelos experimentais de alergia respiratória, células T auxiliares (Th2)...

Allergies affect about 20-30% of world population and its prevalence and severity of symptoms has increased in recent decades. Existing therapies to respiratory tract disorders are extense, with side effects, not effective for severe patients and depending on the allergen removal. An alternative for these patients is the induction of immune tolerance by cell therapy with dendritic cells pulsed with the allergen. This study aimed to evaluate the effect of myeloid dendritic cells sensitized in vitro with B. tropicalis extract in a murine model of respiratory allergy. In experimental models of respiratory allergy, T helper cells (Th2)...

Mucosal dendritic cells shape mucosal immunity

Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases.