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Made available in DSpace on 2022-04-29T08:37:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The social wasp Polybia paulista (Hymenoptera, Vespidae) is highly aggressive, being responsible for many medical occurrences. One of the most allergenic components of this venom is Antigen 5 (Poly p 5). The possible modulation of the in vitro immune response induced by antigen 5 from P. paulista venom, expressed recombinantly (rPoly p 5), on BALB/c mice peritoneal macrophages, activated or not with LPS, was assessed. Here, we analyzed cell viability changes, expression of the phosphorylated form of p65 NF-κB subunit, nitric oxide (NO), proinflammatory cytokines production, and co-stimulatory molecules (CD80, CD86). The results suggest that rPoly p 5 does not affect NO production nor the expression of co-stimulatory molecules in mouse peritoneal macrophages. On the other hand, rPoly p 5 induced an increase in IL-1β production in non-activated macrophages and a reduction in the production of TNF-α and MCP-1 cytokines in activated macrophages. rPoly p 5 decreased the in vitro production of the phosphorylated p65 NF-κB subunit in non-activated macrophages. These findings suggest an essential role of this allergen in the polarization of functional M2 macrophage phenotypes, when analyzed in previously activated macrophages. Further investigations, mainly in in vivo studies, should be conducted to elucidate Polybia paulista Ag5 biological role in the macrophage functional profile modulation. Laboratório de Biologia Molecular de Artrópodes—LBMA Instituto de Biologia—IB Universidade Estadual Paulista Câmpus Rio Claro—UNESP-RC, Avenida 24-A, n◦1515, Bela Vista Laboratório de Imunologia Translacional—LIT Departamento de Clínica Médica Faculdade de Ciências Médicas—FCM Universidade Estadual de Campinas—UNICAMP Cidade Universitária “Zeferino Vaz”, Rua Tessália Vieira de Camargo, n◦126 Departamento de Biomedicina Faculdade de Americana—FAM, Avenida Joaquim Bôer, n◦733, Jardim Luciane Faculdade de Medicina Universidade Anhembi Morumbi, Av. Rio das Pedras, 1601-Pompéia Laboratório de Biologia Molecular de Artrópodes—LBMA Instituto de Biologia—IB Universidade Estadual Paulista Câmpus Rio Claro—UNESP-RC, Avenida 24-A, n◦1515, Bela Vista FAPESP: 2017/07988-2 FAPESP: 2017/18422-0 FAPESP: 2019/02298-3

Colorectal cancer is considered a disease of the elderly population. Since the number of geriatric patients continues to rise, monoclonal antibody therapy is the most promising therapy in the recent research. Presently, the monoclonal antibodies most frequently used in the treatment of colorectal tumors are bevacizumab, cetuximab, panitumumab, and ramucirumab. Bevacizumab is a monoclonal antibody that acts on VEGF. Cetuximab and panitumumab act on EGFR. Ramucirumab binds directly to the ligand-binding pocket of VEGFR-2 to block the binding of VEGF-A, VEGF-C, and VEGF-D. These monoclonal antibodies, alone or in association with radiotherapy or chemotherapy, are presenting good results and are increasing patient survival, despite the side effects. Due to the limited number of molecules available, several studies are trying to develop new monoclonal antibodies for the treatment of colorectal tumors. Among those being studied, some recent molecules are in phase I and/or II trials and are yielding advantageous results, such as anti-DR5, anti-Fn14, anti-IGF-1R, anti-EGFR, anti-NRP1, and anti-A33 antibodies. This has been successful in reducing side effects and in treating nonresponsive patients.

Dendritic cells (DCs) play a crucial role in balancing immune responses, and in that sense the interactions between the B7-1 and B7-2 molecules expressed on DCs and CD28 and CTLA-4 on helper T cells are fundamental. While coupling of B7 and CD28 molecules activates immune responses, binding of B7 to CTLA4 results in its blockade. CTLA4-Ig fusion protein, a competitor molecule of the B7-CD28 interaction, has been used for the development of immunological tolerance both experimentally and in patients. Here, we evaluated the effects of adoptive transfer of bone marrow-derived dendritic cells (BMDCs) pulsed with CTLA4-Ig in TNBS-induced colitis. CTLA4-Ig-modulated BMDCs or naïve BMDC were administered intravenously to BALB/c mice prior to TNBS rectal instillation. Five days later, spleens and colon segments were removed for immunological and histological analysis. Our results showed that the adoptive transfer of CTLA4-Ig-modulated BMDCs was able to reduce the severity of inflammation caused by the administration of TNBS, in view of tissue integrity and reduced leukocyte infiltration in the colon segments of the treated mice compared to controls. Non-specific spleen cell activation in vitro showed a reduction in the frequency of CD4+ IL-17+ T cells and CD4+ IFN-γ+ T cells as well as IL-9 secretion in cultures. To our knowledge, this is the first description of the beneficial effects of treatment with CTLA4-Ig modulated BMDC in experimental colitis.

Background: Methylphenidate is the first-choice drug to the treatment of patients with attention deficit/hyperactivity disorder (ADHD). However, there was an increase in the indiscriminate use of this drug. Objectives We aim to describe the mechanisms of action as well as the side effects of this drug and indiscriminate use of this medicine in Brazil and worldwide. Methods: We performed a bibliographic review on electronic scientific site as PubMed, Scielo and Google Scholar. Results: Forty-five articles were found and, among them, 28 were selected. Full article available in the international and national literature were selected based on key words: methylphenidate; action mechanism; adverse effects and ADHD. Articles published before 2003 were excluded. Discussion/Conclusions: Methylphenidate acts directly on three distinct regions of the central nervous system by blocking the reuptake of the hormone dopamine and noradrenaline. Nervousness, nasopharyngitis, insomnia, nausea are the most common adverse effects caused using methylphenidate. The less frequent reactions are headache, alteration in blood pressure and metabolic, hematological, immune changes. Further studies are necessary for an in-depth assessment of the mechanism of action and side effects of this drug on ADHD.

Made available in DSpace on 2018-12-11T16:53:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-05-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Introduction In addition to conventional therapies, several new strategies have been proposed for modulating autoimmune diseases, including the adoptive transfer of immunological cells. In this context, dendritic cells (DCs) appear to be one of the most promising treatments for autoimmune disorders. The present study aimed to evaluate the effects of adoptive transfer of DCs obtained from both naïve and ovalbumin (OVA)-tolerant mice on the severity of TNBS induced colitis and analyze the eventual protective mechanisms. Methods and results To induce oral tolerance, BALB/c mice were fed 4mg/mL OVA solution for seven consecutive days. Spleen DCs were isolated from tolerant (tDC) and naïve (nDC) mice, and then adop-tively transferred to syngeneic mice. Three days later, colitis was induced in DC treated mice by intrarectal instillation of 100μg2,4,6-trinitrobenzenesulfonic acid (TNBS) dissolved in 50% ethanol. Control subjects received only intrarectal instillation of either TNBS solution or a vehicle. Five days later, mice from all groups were euthanized and examined for physiological and immunological parameters. Regarding the phenotype, we observed that the frequencies of CD11+ MHC II+ and CD11+ MHCII+ CD86+ cells were significantly lower in DCs isolated from tolerant mice than in those from naive mice. However, pretreatment with both types of DCs was able to significantly reduce clinical signs of colitis such as diarrhea, rectal prolapse, bleeding, and cachexia, although only treatment with tDCs was able to prevent weight loss from instillation of TNBS. In vitro proliferation of spleen cells from mice treated with either type of DCs was significantly lower than that observed in splenic cell cultures of naïve mice. Institute of Biosciences Universidade Estadual Paulista UNESP Faculty of Food Engineering University of Campinas UNICAMP Department of Food School of Nutrition Federal University of Ouro Preto Department of Biochemistry and Tissue Biology Institute of Biology University of Campinas UNICAMP Department of Genetics Evolution Microbiology and Immunology Institute of Biology University of Campinas UNICAMP Department of Biomedical Science Faculty of Americana FAM Institute of Biosciences Universidade Estadual Paulista UNESP FAPESP: 2013/20258-2 FAPESP: 2014/08591-0 FAPESP: 2014/086192 FAPESP: 2014/167010 FAPESP: 2015/09326-1

Made available in DSpace on 2018-12-11T16:46:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-03-01 Dendritic cells (DC) are potential tools for therapeutic applications and several strategies to generate tolerogenic DCs are under investigation. When activated by cytokines and microbial products, DCs express mediators that modulate immune responses. In this regard, the metabolites generated by the activities of inducible nitric oxide synthase (iNOS) and arginase in DCs seem to play important roles. Here, we evaluated the effects of adoptive transfer of DCs generated in vitro from bone marrow precursors (BMDC) modulated with L-NAME (Nω-nitro-L-arginine methyl ester) and NOHA (NG-Hydroxy-L-arginine), inhibitors of iNOS and arginase, respectively, upon the immune response of the wild type (BALB/c) and OVA-TCR transgenic (DO11.10) mice. The modulation with L-NAME increased CD86 expression in BMDC, whereas treatment with NOHA increased both CD80 and CD86 expression. Adoptive transfer of either L-NAME- or NOHA-modulated BMDCs to BALB/c mice reduced the plasma levels of ovalbumin-specific antibody as well as proliferation and cytokine secretion in cultures of spleen cells in comparison adoptive transfer of non-modulated DCs. Conversely, transfer of both modulated and non-modulated BMDCs had no effect on immune response of DO11.10 mice. Together, these results show that the treatment with iNOS and Arg inhibitors leads to increased expression of co-stimulatory molecules in DCs, and provides evidences that L-arginine metabolism may be an important therapeutic target for modulating immune responses in inflammatory disorders. Department of Genetics Evolution and Bioagents Institute of Biology University of Campinas UNICAMP Department of Biomedical Science Faculty of Americana FAM Institute of Biosciences Universidade Estadual Paulista UNESP Medical School University of Campinas UNICAMP Institute of Biosciences Universidade Estadual Paulista UNESP

Made available in DSpace on 2018-12-11T16:45:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Introduction Literature data have shown that the consumption of dietary proteins may cause modulatory effects on the host immune system, process denominated oral tolerance by bystander suppression. It has been shown that the bystander suppression induced by dietary proteins can improve inflammatory diseases such as experimental arthritis. Here, we evaluated the effects of oral tolerance induced by ingestion of ovalbumin (OVA) on TNBS-induced colitis in mice, an experimental model for human Crohn's disease. Methods and Results Colitis was induced in BALB/c mice by instilling a single dose of TNBS (100 mg/kg) in ethanol into the colon. Tolerized mice received OVA (4mg/mL) dissolved in the drinking water for seven consecutive days, prior to or concomitantly with the intrarectal instillation. Control groups received protein-free water and ethanol by intrarectal route. We observed that either the prior or concomitant induction of oral tolerance were able to reduce the severity of colitis as noted by recovery of body weight gain, improvement of clinical signs and reduction of histological abnormalities. The in vitro proliferation of spleen cells from tolerant colitic mice was lower than that of control mice, the same as the frequencies of CD4+ T cells secreting IL-17 and IFN-ã. The frequencies of regulatory T cells and T cells secreting IL-10 have increased significantly in mice orally treated with OVA. The levels of inflammatory cytokines (IL-17A, TNF-α, IL-6 and IFN-ã) were lower in supernatants of cells from tolerant colitic mice, whereas IL-10 levels were higher. Conclusion Our data show that the modulation of immune response induced by oral tolerance reduces the severity of experimental colitis. Such modulation may be partially attributed to the increase of Treg cells and reduction of pro-inflammatory cytokines in peripheral lymphoid organs of tolerant mice by bystander suppression. Department of Genetics Evolution and Bioagents Institute of Biology State University of Campinas UNICAMP Institute of Biosciences Universidade Estadual Paulista UNESP Faculty of Food Engineering University of Campinas UNICAMP Department of Histology and Embryology Institute of Biology State University of Campinas UNICAMP Department of Biomedical Science Faculty of Americana FAM Institute of Biosciences Universidade Estadual Paulista UNESP FAPESP: 2013/20258-2#2014/086192#2015/09326-1#2014/1670102014/08591-0

Dendritic cells (DCs), the most important professional antigen-presenting cells (APC), play crucial role in both immunity and tolerance. It is well known that DCs are able to mount immune responses against foreign antigens and simultaneously tolerate self-antigens. Since DCs can be modulated depending on the surrounding microenvironment, they can act as a bridge between innate and adaptive immunity. However, the mechanisms that support this dual role are not entirely clear. Recent studies have shown that DCs can be manipulatedex vivoin order to trigger their tolerogenic profile, what can be a tool to be used in clinical trials aiming the treatment of various diseases and the prevention of transplant rejection. In this sense, the blockage of costimulatory molecules on DC, in the attempt of inhibiting the second signal in the immunological synapse, can be considered as one of the main strategies under development. This review brings an update on current therapies using tolerogenic dendritic cells modulated with costimulatory blockers with the aim of reducing transplant rejection. However, although there are current clinical trials using tolerogenic DC to treat allograft rejection, the actual challenge is to modulate these cells in order to maintain a permanent tolerogenic profile.

In this work, we evaluated the effects of administration of OVA on phenotype and function of intraepithelial lymphocytes (IELs) from small intestine of transgenic (TGN) DO11.10 and wild-type BALB/c mice. While the small intestines from BALB/c presented a well preserved structure, those from TGN showed an inflamed aspect. The ingestion of OVA induced a reduction in the number of IELs in small intestines of TGN, but it did not change the frequencies of CD8+and CD4+T-cell subsets. Administration of OVA via oral + ip increased the frequency of CD103+cells in CD4+T-cell subset in IELs of both BALB/c and TGN mice and elevated its expression in CD8β+T-cell subset in IELs of TGN. The frequency of Foxp3+cells increased in all subsets in IELs of BALB/c treated with OVA; in IELs of TGN, it increased only in CD25+subset. IELs from BALB/c tolerant mice had lower expression of all cytokines studied, whereas those from TGN showed high expression of inflammatory cytokines, especially of IFN-γ, TGF-β, and TNF-α. Overall, our results suggest that the inability of TGN to become tolerant may be related to disorganization and altered proportions of inflammatory/regulatory T cells in its intestinal mucosa.

The limited amount of information on the primary age-related deficiencies in the innate immune system led us to study the production of inducible nitric oxide synthase (iNOS), arginase, and cytokines in macrophages of young (8 weeks old) and old (72 weeks old) female BALB/c mice. We first evaluated iNOS and arginase inducers on peritoneal (PMΦ) and bone marrow-derived (BMMΦ) macrophages of young BALB/c and C57BL/6 mice, and then investigated their effects on macrophages of old mice. Upon stimulation with lipopolysaccharide (LPS), resident and thioglycolate-elicited PMΦ from young mice presented higher iNOS activity than those from old mice (54.4%). However, LPS-stimulated BMMΦ from old mice showed the highest NO levels (50.1%). Identical NO levels were produced by PMΦ and BMMΦ of both young and old mice stimulated with interferon-γ. Arginase activity was higher in resident and elicited PMΦ of young mice stimulated with LPS (48.8 and 32.7%, respectively) and in resident PMΦ stimulated with interleukin (IL)-4 (64%). BMMΦ of old mice, however, showed higher arginase activity after treatment with IL-4 (46.5%). In response to LPS, PMΦ from old mice showed the highest levels of IL-1α (772.3 ± 51.9 pg/mL), whereas, those from young mice produced the highest amounts of tumor necrosis factor (TNF)-α (937.2 ± 132.1 pg/mL). Only TNF-α was expressed in LPS-treated BMMΦ, and cells from old mice showed the highest levels of this cytokine (994.1 ± 49.42 pg/mL). Overall, these results suggest that macrophages from young and old mice respond differently to inflammatory stimuli, depending on the source and maturity of the cell donors.

Aging is accompanied by a decrease in several physiological functions that make older individuals less responsive to environmental challenges. In the present study, we analyzed the immune response of female BALB/c mice (N = 6) of different ages (from 2 to 96 weeks) and identified significant age-related alterations. Immunization with hapten-protein (trinitrophenyl-bovine serum albumin) conjugates resulted in lower antibody levels in the primary and secondary responses of old mice (72 weeks old). Moreover, young mice (2, 16, and 32 weeks old) maintained specific antibodies in their sera for longer periods after primary immunization than did old mice. However, a secondary challenge efficiently induced memory in old mice, as shown by the increased antibody levels in their sera. The number of CD4+ and CD8+ T cells in the spleen increased until 8 weeks of age but there was no change in the CD4+/CD8+ ratio with aging. Splenic T cells from old mice that had or had not been immunized were less responsive to concanavalin-A and showed reduced cytokine production compared to young mice (IL-2: 57-127 vs 367-1104 pg/mL, IFN-gamma: 2344-12,836 vs 752-23,106 pg/mL and IL-10: 393-2172 vs 105-2869 pg/mL in old and young mice, respectively). These data suggest that there are significant changes in the organization of the immune system throughout life. However, the relevance of these alterations for the functioning of the immune system is unknown.

Dietary proteins play an important role in the regulation of systemic immune response, in a phenomenon known as oral tolerance (OT). To evaluate the effects of OT on a murine model of type II collagen (CII) plus ovalbumin (OVA)-induced arthritis (CIA), mice were fed with OVA either before or after CIA induction. OT significantly reduced the paw edema and synovial inflammation, as well as serum levels of anti-CII, the ex vivo proliferation and inflammatory cytokine production by spleen cells from CIA mice. The frequencies of Foxp3(+) and IL-10(+) cells were higher, whereas IFNγ(+) cells and IL-17(+) cells were lower, among gated CD4(+) spleen T cells from tolerized CIA mice than in those from non-tolerized CIA mice. Adoptive transfer of tolerogenic dendritic cells (DCs) before CIA induction mimics the effects observed in the OT. We demonstrate here that bystander suppression induced by OT can modify the course of CIA and tolerogenic DCs play a role this phenomenon.