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1.
Vet Parasitol Reg Stud Reports ; 47: 100951, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199694

RESUMO

Taeniasis/cysticercosis complex caused by Taenia solium, is a serious public health problem and causes major economic losses to swine producers in developing countries in Asia, Africa and the Americas. Despite scarce epidemiological data, Guatemala is considered endemic for T. solium. A cross-sectional study was conducted in Azacualpa and Malpais, two villages in the department of Zacapa, to assess the prevalence of swine cysticercosis and associated factors. Between March and October 2019, 149 pigs were examined by tongue palpation and serum samples were then collected to detect antibodies by ab-ELISA, and necropsy was performed on pigs that were positive by tongue palpation and/or ab-ELISA, to assess parasite load. Pig owners were asked to fill out a questionnaire on factors related to pig husbandry and occurrence of swine cysticercosis. Pearson's chi-square test and multivariate analysis were used to measure the association between serological results and other variables (p < 0.05 was considered significant). The seroprevalence of swine cysticercosis was 13.4% (13/97, 95% C.I. 6.6%-20.2%) and 25% (13/52, 95% C.I. 13.2%-36.8%) in Azacualpa and Malpais, respectively, yielding an overall seroprevalence of 17.4% (26/149, 95% C.I. 11.4%-23.5%). Parasite loads ranged from 1 to over 23,000 metacestodes per carcass. No bivariate association was found between exposure variables and seropositivity. A positive diagnosis by tongue palpation increased the odds of finding pigs seropositive for cysticercosis by a factor of 16.1 in the multivariate analysis. Despite the high prevalence and parasite load of T. solium, risk factors associated with cysticercosis were not significant in this study.


Assuntos
Cisticercose , Doenças dos Suínos , Animais , Suínos , Guatemala/epidemiologia , Estudos Transversais , População Rural , Estudos Soroepidemiológicos , Cisticercose/epidemiologia , Cisticercose/veterinária , Doenças dos Suínos/epidemiologia
2.
Appl Microbiol Biotechnol ; 108(1): 179, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280035

RESUMO

Several COVID-19 vaccines use adenovirus vectors to deliver the SARS-CoV-2 spike (S) protein. Immunization with these vaccines promotes immunity against the S protein, but against also the adenovirus itself. This could interfere with the entry of the vaccine into the cell, reducing its efficacy. Herein, we evaluate the efficiency of an adenovirus-vectored vaccine (chimpanzee ChAdOx1 adenovirus, AZD1222) in boosting the specific immunity compared to that induced by a recombinant receptor-binding domain (RBD)-based vaccine without viral vector. Mice immunized with the AZD1222 human vaccine were given a booster 6 months later, with either the homologous vaccine or a recombinant vaccine based on RBD of the delta variant, which was prevalent at the start of this study. A significant increase in anti-RBD antibody levels was observed in rRBD-boosted mice (31-61%) compared to those receiving two doses of AZD1222 (0%). Significantly higher rates of PepMix™- or RBD-elicited proliferation were also observed in IFNγ-producing CD4 and CD8 cells from mice boosted with one or two doses of RBD, respectively. The lower efficiency of the ChAdOx1-S vaccine in boosting specific immunity could be the result of a pre-existing anti-vector immunity, induced by increased levels of anti-adenovirus antibodies found both in mice and humans. Taken together, these results point to the importance of avoiding the recurrent use of the same adenovirus vector in individuals with immunity and memory against them. It also illustrates the disadvantages of ChAdOx1 adenovirus-vectored vaccine with respect to recombinant protein vaccines, which can be used without restriction in vaccine-booster programs. KEY POINTS: • ChAdOx1 adenovirus vaccine (AZD1222) may not be effective in boosting anti-SARS-CoV-2 immunity • A recombinant RBD protein vaccine is effective in boosting anti-SARS-CoV-2 immunity in mice • Antibodies elicited by the rRBD-delta vaccine persisted for up to 3 months in mice.


Assuntos
Vacinas contra Adenovirus , COVID-19 , Vacinas , Humanos , Animais , Camundongos , Pan troglodytes , ChAdOx1 nCoV-19 , Vacinas contra COVID-19/genética , SARS-CoV-2 , COVID-19/prevenção & controle , Adenoviridae/genética , Vacinação , Anticorpos Antivirais , Anticorpos Neutralizantes
3.
Cancer Immunol Immunother ; 72(11): 3825-3838, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37736849

RESUMO

Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/patologia , Exaustão das Células T , Linfócitos do Interstício Tumoral/metabolismo , Prognóstico , Antineoplásicos/uso terapêutico , Linfócitos T CD8-Positivos/metabolismo
4.
Pathogens ; 12(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37764924

RESUMO

Extraparenchymal neurocysticercosis (EP-NC) is a chronic, potentially life-threatening disease that responds poorly to initial anthelmintic drug therapy. A depressed specific reactivity of peripheral lymphocytes and an increased level of specific Tregs accompanies EP-NC. The immune checkpoint pathway PD-1 and its ligand PD-L1 downregulates effector T cells, causing specific immune suppression in chronic diseases. This study explored whether their soluble forms, sPD-1/sPD-L1, are present in plasma among patients with EP-NC and if their levels could be associated with treatment response. A total of 21 patients with vesicular EP-NC and 22 healthy controls were included. Patients received standard treatment and were followed for six months to assess treatment response by assessing changes in cyst volume determined with 3D MRI. The presence of both sPD-1 and sPD-L1 was more frequently detected among patients with EP-NC than in healthy controls and had higher concentrations. Among patients, higher pre-treatment levels of both markers were associated with a poor treatment response, and the sensitivity and specificity of the sPD-1/sPD-L1 ratio for predicting any response to treatment were high. Our results are consistent with the presence of lymphocyte exhaustion and open new research perspectives to improve the prognosis of patients with this severe disease.

5.
Brain Sci ; 13(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37508953

RESUMO

BACKGROUND: Neurocysticercosis (NCC) is endemic in non-developed regions of the world. Two forms of NCC have been described, for which neurological morbidity depends on the location of the lesion, which can be either within the cerebral parenchyma or in extraparenchymal spaces. The extraparenchymal form (EXP-NCC) is considered the most severe form of NCC. EXP-NCC often requires several cycles of cysticidal treatment and the concomitant use of glucocorticoids to prevent increased inflammation, which could lead to intracranial hypertension and, in rare cases, to death. Thus, the improvement of EXP-NCC treatment is greatly needed. METHODS: An experimental murine model of EXP-NCC, as an adequate model to evaluate new therapeutic approaches, and the parameters that support it are described. EXP-NCC was established by injecting 30 Taenia crassiceps cysticerci, which are less than 0.5 mm in diameter, into the cisterna magna of male and female Wistar rats. RESULTS: Cyst implantation and infection progression were monitored by detecting the HP10 antigen and anti-cysticercal antibodies in the serum and cerebral spinal fluid (CSF) of infected rats and by magnetic resonance imaging. Higher HP10 levels were observed in CSF than in the sera, as in the case of human EXP-NCC. Low cell recruitment levels were observed surrounding established cysticerci in histological analysis, with a modest increase in GFAP and Iba1 expression in the parenchyma of female animals. Low cellularity in CSF and low levels of C-reactive protein are consistent with a weak inflammatory response to this infection. After 150 days of infection, EXP-NCC is accompanied by reduced levels of mononuclear cell proliferation, resembling the human disease. EXP-NCC does not affect the behavior or general status of the rats. CONCLUSIONS: This model will allow the evaluation of new approaches to control neuroinflammation and immunomodulatory treatments to restore and improve the specific anti-cysticercal immunity in EXP-NCC.

6.
Parasitol Res ; 122(9): 2147-2154, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37428312

RESUMO

Neurocysticercosis is a heterogeneous disease, and the patient's sex seems to play a role in this heterogeneity. Hosts' sexual dimorphism in cysticercosis has been largely explored in the murine model of intraperitoneal Taenia crassiceps cysticercosis. In this study, we investigated the sexual dimorphism of inflammatory responses in a rat model of extraparenchymal neurocysticercosis caused by T. crassiceps. T. crassiceps cysticerci were inoculated in the subarachnoid space of Wistar rats (25 females, 22 males). Ninety days later, the rats were euthanized for histologic, immunohistochemistry, and cytokines studies. Ten animals also underwent a 7-T magnetic resonance imaging (MRI). Female rats presented a higher concentration of immune cells in the arachnoid-brain interface, reactive astrogliosis in the periventricular region, in situ pro-inflammatory cytokine (interleukin [IL]-6) and anti-inflammatory cytokine (IL-10), and more intense hydrocephalus on MRI than males. Intracranial hypertension signals were not observed during the observational period. Overall, these results suggest sexual dimorphism in the intracranial inflammatory response that accompanied T. crassiceps extraparenchymal neurocysticercosis.


Assuntos
Cisticercose , Neurocisticercose , Taenia , Masculino , Camundongos , Feminino , Ratos , Animais , Neurocisticercose/diagnóstico por imagem , Neurocisticercose/patologia , Modelos Animais de Doenças , Caracteres Sexuais , Ratos Wistar , Citocinas , Interleucina-6 , Camundongos Endogâmicos BALB C
7.
Infect Immun ; 91(7): e0051722, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37341599

RESUMO

Parasitic diseases are a major public health problem worldwide. Plant-derived products appear to be ideal candidates from a biotechnological perspective, being sustainable and environmentally friendly. The antiparasitic properties of Carica papaya have been attributed to some of its components, including papain and other compounds that are concentrated in the latex and seeds. This study demonstrated in vitro a high and insignificantly different cysticidal activity of soluble extract that was obtained after the disruption of nontransformed wild-type (WT) cells as well as transformed papaya calluses (PC-9, PC-12, and PC-23) and papaya cell suspensions (CS-9, CS-12, and CS-23). In vivo, cell suspensions of CS-WT and CS-23 that had been previously lyophilized were tested with respect to their cysticidal effects, compared with those of three commercial antiparasitic drugs. CS-WT and CS-23 together reduced the number of cysticerci, the number of buds, and the percentage of calcified cysticerci in a similar extent to albendazole and niclosamide, whereas ivermectin was less effective. Mice were then orally immunized with CS-23 that expressed the anti-cysticercal KETc7 antigen (10 µg/mouse), CS-WT (10 mg/mouse), or both together to evaluate their preventive properties. CS-23 and CS-WT significantly reduced the expected parasite and increased the percentage of calcified cysticerci as well as recovery, being more effective when employed together. The results reported in this study support the feasibility of the development of an anti-cysticercosis vaccine from cells of C. papaya in in vitro cultures, as they are a source of an anthelmintic, natural, and reproducible product.


Assuntos
Carica , Camundongos , Animais , Suspensões , Albendazol , Extratos Vegetais/farmacologia , Sementes
8.
PLoS Negl Trop Dis ; 17(6): e0011386, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37262055

RESUMO

BACKGROUND: The morbidity and mortality of extraparenchymal neurocysticercosis (EP-NC) remain high and effectiveness of current medical treatment is suboptimal. Various factors have been implicated in the severity of EP-NC and in the poor response to treatment, but the possible role of host immune and endocrine systems has not yet been examined thoroughly. METHODOLOGY/PRINCIPAL FINDINGS: 42 participants with EP-NC before receiving standard treatment and 25 healthy controls were included in the study. Treatment response was assessed by comparing pre/post treatment parasite volumes from 3D MRI. Prior to treatment among participants with EP-NC, specific stimulation induced an increased specific proliferative response accompanied by a significant increase in IL-4, NK, NKT, Bregs and Tregs cells, whereas in healthy controls, specific stimulation induced a significant increase in IL-1ß, IL-5, CCL5, IL-6, TNF-α, NK and Bregs cells. Significant differences between participants with EP-NC and healthy controls in the specific inflammatory response were observed. Participants with EP-NC prior to treatment had significantly weaker responses of proinflammatory cytokines (IL-6, TNF-α) and NK cells, and stronger IL-4 response. Anthelmintic treatment did not promote significant peripheral immunological changes at any time, although inflammation was sustained in the cerebrospinal fluid. Serum estradiol concentration significantly decreased after anthelmintic treatment among males, and cortisol correlated negatively with IL-6 and positively with IFN-γ levels. No pre-treatment immunologic or endocrinologic parameters were significantly associated with response to treatment. CONCLUSION/SIGNIFICANCE: Prior to anthelmintic treatment, EP-NC was characterized by low lymphocyte reactivity accompanied by a regulatory response, which may be involved in the lack of peripheral immunological changes during and after treatment, although a central inflammatory response was present. This weak specific peripheral response could favor the chronicity of the infection and the poor response to treatment. Our findings highlight the need for new anti-inflammatory treatment focused on the central nervous system with less systemic immunosuppressive effects.


Assuntos
Neurocisticercose , Masculino , Humanos , Neurocisticercose/tratamento farmacológico , Fator de Necrose Tumoral alfa , Interleucina-4 , Interleucina-6 , Citocinas , Células Matadoras Naturais
9.
Exp Parasitol ; 250: 108529, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37015309

RESUMO

Neurocysticercosis, caused by the larval stage of Taenia solium, is a life-threatening condition and the most severe form of the disease. Yet, despite being a required link in the parasite life cycle, tapeworm carriers are rarely reported. This study is aimed to find and evaluate T. solium carriers, describing some characteristics of these patients and the treatment. Taeniasis cases were searched for in various Mexican states from 1983 to 2016. Previous informed consent, tapeworm-carrier patients were administered with niclosamide and a saline purge. Parasite specimens were recovered and identified, both morphologically and by PCR. From 117 treated patients, Taenia sp. specimens were obtained from 46 subjects (47.8%). From these, complete parasites were recovered from 42 (90.5%), and only detached proglottids from 4 patients. Cases were more frequent in Morelos, Chiapas, and Guerrero. More than one adult cestode was recovered from 4 patients (9.5%). To improve treatment efficacy and adherence, the drug was administered in late afternoon, resulting a high recovery yield of complete parasites (90.5%). The success rate of deworming campaigns in areas of Mexico and the world that are endemic for Taenia sp. could be improved by administering the treatment at times that do not interfere with the patients' daily activities, and national health authorities could apply this simple strategy to help eradication efforts in endemic areas. The detection of carriers will only be possible through the coordinated efforts of public and private health services, a better education of the general population to improve self-detection, and adequate, personalized diagnostic procedures for suspect cases.


Assuntos
Infecções por Cestoides , Cisticercose , Neurocisticercose , Taenia solium , Teníase , Adulto , Animais , Humanos , Fezes/parasitologia , Teníase/diagnóstico , Teníase/tratamento farmacológico , Teníase/epidemiologia , Neurocisticercose/diagnóstico , Neurocisticercose/tratamento farmacológico , Neurocisticercose/epidemiologia , Taenia solium/genética , Cisticercose/diagnóstico
10.
Phytother Res ; 37(8): 3394-3407, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37012651

RESUMO

Triple-negative breast cancer (TNBC) does not express estrogen receptor, progesterone receptor, and human epidermal growth factor receptor; therefore, TNBC lacks targeted therapy, and chemotherapy is the only available treatment for this illness but causes side effects. A putative strategy for the treatment of TNBC could be the use of the polyphenols such as α-Mangostin (α-M), which has shown anticancerogenic effects in different cancer models and can modulate the inflammatory and prooxidant state in several pathological models. The redox state, oxidative stress (OS), and oxidative damage are highly related to cancer development and its treatment. Thus, this study aimed to evaluate the effects of α-M on redox state, mitochondrial metabolism, and apoptosis in 4T1 mammary carcinoma cells. We found that α-M decreases both protein levels and enzymatic activity of catalase, and increases reactive oxygen species, oxidized proteins and glutathione disulfide, which demonstrates that α-M induces oxidative damage. We also found that α-M promotes mitochondrial dysfunction by abating basal respiration, the respiration ligated to oxidative phosphorylation (OXPHOS), and the rate control of whole 4T1 cells. Additionally, α-M also decreases the levels of OXPHOS subunits of mitochondrial complexes I, II, III, and adenosine triphosphate synthase, the activity of mitochondrial complex I as well as the levels of peroxisome proliferator-activated receptor-gamma co-activator 1α, showing a mitochondrial mass reduction. Then, oxidative damage and mitochondrial dysfunction induced by α-M induce apoptosis of 4T1 cells, which is evidenced by B cell lymphoma 2 decrease and caspase 3 cleavage. Taken together, our results suggest that α-M induces OS and mitochondrial dysfunction, resulting in 4T1 cell death through apoptotic mechanisms.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Mitocôndrias
11.
Pathog Glob Health ; 117(1): 5-13, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35657099

RESUMO

In Guatemala, neurocysticercosis (NCC) was first recognized in 1940; since then, cases of NCC have been reported in all Guatemalan departments. However, epidemiological studies on Taenia solium infections are scarce and most information remains unpublished. This study aims to provide evidence of T. solium infections as a public health problem in Guatemala. All information available, either published or unpublished, on T. solium infections in the country was compiled. Official data from the Ministry of Health for the period 2003-2019 were reviewed and analyzed, and all cases of T. solium infections were classified and counted. In total, 5246 cases of taeniasis and 454 cases of human cysticercosis were recorded. On the other hand, 44 studies were identified, mostly from local journals, which included 1951 cases of taeniasis, 2873 cases of human cysticercosis of which 543 were classified with complete diagnosis, and 2590 cases of porcine cysticercosis. Cases were classified by geographic region, patient sex, and Taenia species in taeniasis cases when information was available, and the departments with the highest number of taeniasis and cysticercosis cases were identified. Meanwhile, in Zacapa, a northeastern department of Guatemala with one the highest number of taeniasis cases, a young man diagnosed with a severe form of NCC and two cases of porcine cysticercosis (both confirmed by necropsy) were identified. Taken together, the data herein reported indicate that T. solium infections are a major health problem in Guatemala that needs to be addressed.


Assuntos
Cisticercose , Neurocisticercose , Taenia solium , Teníase , Masculino , Humanos , Animais , Suínos , Saúde Pública , Guatemala/epidemiologia , Cisticercose/epidemiologia , Teníase/epidemiologia , Teníase/diagnóstico , Neurocisticercose/epidemiologia
12.
Vaccine ; 40(45): 6489-6498, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36195474

RESUMO

The rapid spread of COVID-19 on all continents and the mortality induced by SARS-CoV-2 virus, the cause of the pandemic coronavirus disease 2019 (COVID-19) has motivated an unprecedented effort for vaccine development. Inactivated viruses as well as vaccines focused on the partial or total sequence of the Spike protein using different novel platforms such us RNA, DNA, proteins, and non-replicating viral vectors have been developed. The high global need for vaccines, now and in the future, and the emergence of new variants of concern still requires development of accessible vaccines that can be adapted according to the most prevalent variants in the respective regions. Here, we describe the immunogenic properties of a group of theoretically predicted RBD peptides to be used as the first step towards the development of an effective, safe and low-cost epitope-focused vaccine. One of the tested peptides named P5, proved to be safe and immunogenic. Subcutaneous administration of the peptide, formulated with alumina, induced high levels of specific IgG antibodies in mice and hamsters, as well as an increase of IFN-γ expression by CD8+ T cells in C57 and BALB/c mice upon in vitro stimulation with P5. Neutralizing titers of anti-P5 antibodies, however, were disappointingly low, a deficiency that we will attempt to resolve by the inclusion of additional immunogenic epitopes to P5. The safety and immunogenicity data reported in this study support the use of this peptide as a starting point for the design of an epitope restricted vaccine.


Assuntos
COVID-19 , Vacinas Virais , Cricetinae , Humanos , Camundongos , Animais , SARS-CoV-2 , Epitopos , Glicoproteína da Espícula de Coronavírus/genética , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Anticorpos Antivirais , Imunoglobulina G , Peptídeos , RNA , Óxido de Alumínio , Anticorpos Neutralizantes
13.
Front Cell Infect Microbiol ; 12: 958741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159651

RESUMO

Parasitic diseases have a major impact on human and animal health worldwide. Despite the availability of effective anti-parasitic drugs, their excessive and uncontrolled use has promoted the emergence of drug resistance, severely affecting ecosystems and human health. Thus, developing environmentally friendly antiparasitic treatments is urgently needed. Carica papaya has shown promising effects against infectious diseases. C. papaya embryogenic calluses were genetically modified by our research team to insert immunogenic peptides with the goal of developing an oral anti-cysticercosis vaccine. Among these callus cell lines, one labeled as CF-23, which expresses the KETc7 immunogenic peptide, induced the highest protection levels against experimental cysticercosis. In the process of designing a natural antiparasitic product based on C. papaya that simultaneously induced immunity against cysticercosis, both transformed (SF-23) and untransformed (SF-WT) suspension cultures were produced and optimized. Our results showed a better duplication time (td) for SF-23 (6.9 days) than SF-WT (13.02 days); thus, the SF-23 line was selected for scale-up in a 2-L airlift bioreactor, reaching a td of 4.4 days. This is the first time that a transgenic line of C. papaya has been grown in an airlift bioreactor, highlighting its potential for scale-up cultivation in this type of reactor. Considering the previously reported nematocidal activity of C. papaya tissues, their activity against the nematode Haemonchus contortus of aqueous extracts of SF-WT and SF-23 was explored in this study, with promising results. The information herein reported will allow us to continue the cultivation of the transgenic cell suspension line of C. papaya under reproducible conditions, to develop a new anti-parasitic product.


Assuntos
Carica , Haemonchus , Animais , Antiparasitários/farmacologia , Carica/genética , Linhagem Celular , Ecossistema , Haemonchus/genética , Humanos , Plantas Geneticamente Modificadas
14.
Arch Biochem Biophys ; 730: 109414, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174750

RESUMO

Cancer, a major public health problem, is the fourth cause of death in the world. While cancer mortality has decreased in recent decades due to more effective treatments, mostly based on improving antitumor immunity, some forms of cancer are resistant to these immunotherapies. A promising approach for cancer treatment involves the administration of antitumor and immunomodulatory peptides. Immunomodulatory peptides have been proved to exert antitumor and immunomodulatory effects by activating immune cells such as cytotoxic T cells, with fewer side-effects. A process closely related to the regulation of the immune system by immunomodulatory antitumor peptides is the modulation of the redox state, which has been poorly studied. This review focuses on the redox state regulated by antitumor and immunomodulatory peptides in cancer development, and on the potential of redox state as a therapy associated with these peptides in cancer treatment.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Imunoterapia , Linfócitos T Citotóxicos , Peptídeos/uso terapêutico , Oxirredução
15.
Antioxidants (Basel) ; 12(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36670920

RESUMO

Breast cancer (BC) is the second most common cancer worldwide in women. During the last decades, the mortality due to breast cancer has progressively decreased due to early diagnosis and the emergence of more effective new treatments. However, human epidermal growth factor receptor 2 (HER2) and triple-negative breast cancer (TNBC) remain with poor prognoses. In our research group, we are proposing the GK-1 immunomodulatory peptide as a new alternative for immunotherapy of these aggressive tumors. GK-1 reduced the growth rate of established tumors and effectively reduced lung metastasis in the 4T1 experimental murine model of breast cancer. Herein, the effect of GK-1 on the redox state, mitochondrial metabolism, and autophagy of triple-negative tumors that can be linked to cancer evolution was studied. GK-1 decreased catalase activity, reduced glutathione (GSH) content and GSH/oxidized glutathione (GSSG) ratio while increased hydrogen peroxide (H2O2) production, GSSG, and protein carbonyl content, inducing oxidative stress (OS) in tumoral tissues. This imbalance between reactive oxygen species (ROS) and antioxidants was related to mitochondrial dysfunction and uncoupling, characterized by reduced mitochondrial respiratory parameters and dissipation of mitochondrial membrane potential (ΔΨm), respectively. Furthermore, GK-1 likely affected autophagy flux, confirmed by elevated levels of p62, a marker of autophagy flux. Overall, the induction of OS, dysfunction, and uncoupling of the mitochondria and the reduction of autophagy could be molecular mechanisms that underlie the reduction of the 4T1 breast cancer induced by GK-1.

16.
Front Cell Infect Microbiol ; 11: 630583, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33928043

RESUMO

Murine cysticercosis by Taenia crassiceps is a model for human neurocysticercosis. Genetic and/or immune differences may underlie the higher susceptibility to infection in BALB/cAnN with respect to C57BL/6 mice. T regulatory cells (Tregs) could mediate the escape of T. crassiceps from the host immunity. This study is aimed to investigate the role of Tregs in T. crassiceps establishment in susceptible and non-susceptible mouse strains. Treg and effector cells were quantified in lymphoid organs before infection and 5, 30, 90, and 130 days post-infection. The proliferative response post-infection was characterized in vitro. The expression of regulatory and inflammatory molecules was assessed on days 5 and 30 post-infection. Depletion assays were performed to assess Treg functionality. Significantly higher Treg percentages were observed in BALB/cAnN mice, while increased percentages of activated CD127+ cells were found in C57BL/6 mice. The proliferative response was suppressed in susceptible mice, and Treg proliferation occurred only in susceptible mice. Treg-mediated suppression mechanisms may include IL-10 and TGFß secretion, granzyme- and perforin-mediated cytolysis, metabolic disruption, and cell-to-cell contact. Tregs are functional in BALB/cAnN mice. Therefore Tregs could be allowing parasite establishment and survival in susceptible mice but could play a homeostatic role in non-susceptible strains.


Assuntos
Linfócitos T Reguladores , Taenia , Animais , Imunidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
17.
Expert Rev Anti Infect Ther ; 19(12): 1503-1518, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33794119

RESUMO

INTRODUCTION: Neurocysticercosis is caused by the localization of Taenia solium larvae in the central nervous system. The disease remains endemic in most countries of Latin America, Asia and Africa. While major improvements have been made in its diagnosis and treatment, uncertainties persist regarding the clinical implications and treatment of the inflammatory reaction associated with the disease. AREAS COVERED: In this review, based on PubMed searches, the authors describe the characteristics of the immune-inflammatory response in patients with neurocysticercosis, its clinical implications and the treatment currently administered. The dual role of inflammation (participating in both, the death of the parasite, and the precipitation of serious complications) is discussed. New therapeutic strategies of potential interest are presented. EXPERT OPINION: Inflammatory reaction is the main pathogenic mechanism associated to neurocysticercosis. Its management is mainly based on corticosteroids administration. This strategy had improved prognostic of patients as it allows for the control of most of the inflammatory complications. On the other side, it might be involved in the persistence of parasites in some patients, despite cysticidal treatment, due to its immunosuppressive properties. New strategies are needed to improve therapeutical management, particularly in the severest presentations.


Assuntos
Neurocisticercose , Taenia solium , Corticosteroides/uso terapêutico , Animais , Cysticercus , Humanos , Inflamação/tratamento farmacológico , Neurocisticercose/complicações , Neurocisticercose/tratamento farmacológico , Neurocisticercose/epidemiologia , Taenia solium/fisiologia
18.
PLoS Negl Trop Dis ; 15(2): e0009104, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33600419

RESUMO

The flatworm Taenia solium causes human and pig cysticercosis. When cysticerci are established in the human central nervous system, they cause neurocysticercosis, a potentially fatal disease. Neurocysticercosis is a persisting public health problem in rural regions of Mexico and other developing countries of Latin America, Asia, and Africa, where the infection is endemic. The great variability observed in the phenotypic and genotypic traits of cysticerci result in a great heterogeneity in the patterns of molecules secreted by them within their host. This work is aimed to identify and characterize cysticercal secretion proteins of T. solium cysticerci obtained from 5 naturally infected pigs from Guerrero, Mexico, using 2D-PAGE proteomic analysis. The isoelectric point (IP) and molecular weight (MW) of the spots were identified using the software ImageMaster 2D Platinum v.7.0. Since most secreted proteins are impossible to identify by mass spectrometry (MS) due to their low concentration in the sample, a novel strategy to predict their sequence was applied. In total, 108 conserved and 186 differential proteins were identified in five cysticercus cultures. Interestingly, we predicted the sequence of 14 proteins that were common in four out of five cysticercus cultures, which could be used to design vaccines or diagnostic methods for neurocysticercosis. A functional characterization of all sequences was performed using the algorithms SecretomeP, SignalP, and BlastKOALA. We found a possible link between signal transduction pathways in parasite cells and human cancer due to deregulation in signal transduction pathways. Bioinformatics analysis also demonstrated that the parasite release proteins by an exosome-like mechanism, which could be of biological interest.


Assuntos
Cysticercus/metabolismo , Proteoma , Taenia solium/metabolismo , Animais , Cisticercose/veterinária , Eletroforese em Gel Bidimensional , Proteínas de Helminto/genética , Proteínas de Helminto/isolamento & purificação , Análise de Sequência de Proteína , Transdução de Sinais , Suínos , Doenças dos Suínos/parasitologia , Taenia solium/genética , Taenia solium/crescimento & desenvolvimento
19.
Mol Immunol ; 128: 22-32, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33049560

RESUMO

GK-1 is an immunomodulatory, 18-aa-long peptide that has been proved to promote the activation of mouse peritoneal macrophages and LPS-pulsed mouse bone marrow-derived dendritic cells (BM-DCs). This study is aimed to explore the mechanisms underlying the activation of these antigen-presenting cells (APCs) by GK-1. In our study, GK-1 up-regulated in vitro the expression of CD86 and CD40, and it increased the secretion of NO in bone marrow-derived macrophages (BMDMs). In BM-DCs, GK-1 upregulated the expression of MHC class II and CD86. Additionally, GK-1 was found to be involved in the phosphorylation of MAPK p38, JNK and ERK 1/2 and in Myd88-dependent activation of NF-κB in both antigen-presenting cell types. In vivo, GK-1 increased the secretion of IL-15, CCL2, and IL-6 through a Myd88-dependent mechanism. This study demonstrated that GK-1 promotes the activation and effector activity of APCs through a mechanism dependent on Myd88, probably involving a Toll-like receptor as a target.


Assuntos
Células Apresentadoras de Antígenos/metabolismo , Medula Óssea/metabolismo , Proteínas de Helminto/metabolismo , Helmintos/metabolismo , Inflamação/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Peptídeos Cíclicos/metabolismo , Animais , Antígeno B7-2/metabolismo , Células da Medula Óssea/metabolismo , Antígenos CD40/metabolismo , Células Cultivadas , Citocinas , Células Dendríticas/metabolismo , Feminino , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia
20.
J Neuroimmunol ; 349: 577389, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32977250

RESUMO

Neurocysticercosis (NC) presents two broad clinical entities: extraparenchymal (EP-NC) and parenchymal (P-NC). Using ELISA methodology, we demonstrate autoantibodies to tubulin and the Major oligodendrocyte glycoprotein (MOG) in the CSF of most, but not all, EP-NC samples. Levels of these autoantibodies were considerably reduced or absent in the P-NC samples. There was a striking correlation between levels of anti-tubulin and anti-MOG, and the significant correlation between the levels of autoantibodies and cellularity in the CSF, suggests that stimulation of the autoantibody response may be a function of cerebral inflammation. A hypothetical model to describe the pathogenesis of EP-NC is presented.


Assuntos
Autoanticorpos/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Glicoproteína Mielina-Oligodendrócito/líquido cefalorraquidiano , Neurocisticercose/líquido cefalorraquidiano , Neurocisticercose/diagnóstico por imagem , Tubulina (Proteína)/líquido cefalorraquidiano , Animais , Biomarcadores/líquido cefalorraquidiano , Equador/epidemiologia , Humanos , México/epidemiologia , Neurocisticercose/epidemiologia , Tecido Parenquimatoso/metabolismo , Fragmentos de Peptídeos/líquido cefalorraquidiano , Suínos
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