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1.
Front Immunol ; 14: 1128637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36865534

RESUMO

Eimeria, a cousin of malarial parasites, causes coccidiosis that results in huge losses in the poultry industry. Although live coccidiosis vaccines have been developed and used widely for the successful control of the disease, the mechanism underlying protective immunity remains largely unknown. Using Eimeria falciformis as a model parasite, we observed that tissue-resident memory CD8+ T (Trm) cells accumulated in cecal lamina propria following E. falciformis infection in mice, especially after reinfection. In convalescent mice challenged with a second infection, E. falciformis burden diminished within 48-72 h. Deep-sequencing revealed that CD8+ Trm cells were characterized by rapid up-regulation of effector genes encoding pro-inflammatory cytokines and cytotoxic effector molecules. While FTY720 (Fingolimod) treatment prevented the trafficking of CD8+ T cells in peripheral circulation and exacerbated primary E. falciformis infection, such treatment had no impact on the expansion of CD8+ Trm cells in convalescent mice receiving secondary infection. Adoptive transfer of cecal CD8+ Trm cells conferred immune protection in naïve mice, indicating that these cells provide direct and effective protection against infection. Overall, our findings not only explain a protective mechanism of live oocyst-based anti-Eimeria vaccines but also provide a valuable correlate for assessing vaccines against other protozoan diseases.


Assuntos
Coccidiose , Eimeria , Animais , Camundongos , Linfócitos T CD8-Positivos , Reinfecção , Transferência Adotiva , Cloridrato de Fingolimode , Vacinas Atenuadas
2.
iScience ; 26(4): 106334, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36968087

RESUMO

The control of coccidiosis, causing huge economic losses in the poultry industry, is facing the stagnation of the development of new drugs and the emergence of drug resistance. Thus, the priority for coccidiosis control is to decipher the effect mechanisms and resistance mechanisms of anticoccidial drugs. In this study, we mined and validated a molecular marker for halofuginone resistance in Eimeria tenella through forward and reverse genetic approaches. We screened whole-genome sequencing data and detected point mutations in the ETH2_1020900 gene (encoding prolyl-tRNA synthetase, PRS). Then, we introduced this mutated gene into E. tenella and Toxoplasma gondii and validated that overexpression of this mutated gene confers resistance to halofuginone in vivo and in vitro. These results together show that mutations A1852G and A1854G on the ETH2_1020900 gene are pivotal to halofuginone resistance in E. tenella, encouraging the exploration of mechanisms of drug resistance against other anticoccidial drugs in eimerian parasites.

3.
Int J Parasitol ; 53(2): 81-89, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36549444

RESUMO

Eimeria species are apicomplexan parasites with a direct life cycle consisting of a replicative phase involving multiple rounds of asexual replication in the intestine or other organs including kidneys, liver, and gallbladder, depending on the species, followed by a sexual phase or gamogony involving the development and fertilization of gametes, an essential process for Eimeria transmission. Recent advances in the genetic manipulation of these parasites made it possible to conduct genetic crosses combined with genomic approaches to elucidate the genetic determinants of Eimeria development, virulence, drug resistance, and immune evasion. Here, we employed genetic techniques to generate two transgenic Eimeria acervulina lines, EaGAM56 and EaHAP2, each expressing two unique fluorescent proteins, with one controlled by a constitutive promotor for cross-efficiency analysis and the other by a male or female gametocyte stage-specific promoter to observe sexual development. The expression of fluorescent proteins in the transgenic lines was analyzed in different developmental stages of the E. acervulina life cycle by immunoblotting and by examination of frozen sections using fluorescence microscopy. The effect of infective doses on cross-fertilization was further investigated by conducting several genetic crosses between the two transgenic lines at different doses and ratios. Two transgenic lines expressing constitutive and gametocyte-specific fluorescence proteins were generated and characterized. These transgenic parasites display synchronous development in chickens, comparable with that of the wild type. Genetic crosses between the two transgenic parasites showed that a high rate of oocysts co-expressing the two reporters could be achieved following inoculation with high doses of infective oocysts. We further showed that the proportion of co-transfected oocysts can be modulated by altering the ratio of the transgenic parental lines. Higher infective doses and similar numbers of functional gametocytes from the parents increase the rate of cross-fertilization. Our data highlight the usefulness of genetic manipulation and fluorescently-labeled transgenic gametocytes as tools to study Eimeria development and to elucidate the factors that modulate sexual development. This work sets the stage for the implementation of novel approaches to investigate other aspects of Eimeria pathogenesis, virulence, and drug susceptibility and resistance.


Assuntos
Coccidiose , Eimeria , Parasitos , Doenças das Aves Domésticas , Animais , Feminino , Masculino , Eimeria/genética , Galinhas , Oocistos/genética , Animais Geneticamente Modificados , Estágios do Ciclo de Vida , Fertilização , Coccidiose/parasitologia , Doenças das Aves Domésticas/parasitologia
4.
Vaccines (Basel) ; 9(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34358207

RESUMO

The potential of Eimeria parasites as live vaccine vectors has been reported with successful genetic manipulation on several species like E. tenella, E. mitis and E. necatrix. Among seven Eimeria species infecting chickens, E. acervulina is a highly prevalent, moderately pathogenic species. Thus, it is valuable for the study of transfection and for use as a potential as vaccine vector. In this study, a plasmid containing expression cassette with enhanced yellow fluorescent protein (EYFP), red fluorescent protein (RFP) and 12 copies of extracellular domain of H9N2 avian influenza virus M2 (M2e) protein was used for the transfection. Nucleofected sporozoites were inoculated into birds through wing vein. Recombinant E. acervulina oocysts with 0.1% EYFP+ and RFP+ populations were collected from the feces of the inoculated birds. The fluorescent rate of transgenic parasites reached over 95% after nine successive propagations with a pyrimethamine selection in vivo and fluorescent-activated cell sorting (FACS) of progeny oocysts. The expression of M2e in the transgenic parasites (EaM2e) was confirmed by Western blot and its cytoplasm localization in sporozoites was displayed by an indirect immunofluorescent assay (IFA). Meanwhile, we found that the fecundity of EaM2e was equivalent to that of wild type E. acervulina (EaWT). Taken together, the stable transfection of E. acervulina was successfully established. Future studies will focus on whether transgenic E. acervulina can serve as a live vaccine vector.

5.
Res Vet Sci ; 132: 97-100, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32544634

RESUMO

Aloperine is a major active component in Sophora alopecuroides L that plays diverse pharmacological properties. Recent studies have indicated the potential effect of aloperine against hypertension and cancers. However, possible toxicity of aloperine has not been carefully studied in vivo. The aim of this study was to assess the effect of intraperitoneal aloperine injection on mouse liver and kidney tissues and to investigate the role of CYP450 genes in aloperine-induced toxicity. 72 BALB/c mice were randomly divided into four groups: vehicle control group (normal saline), low-dose group (4 mg/kg), medium-dose group (8 mg/kg), and high-dose group (16 mg/kg). 18 mice in each group were intraperitoneally injected with aloperine daily for 4 weeks, and were then kept for another 1 or 4 weeks without aloperine treatment. Serum was colleted for analysis of serum biochemical indexes including ALT, AST, BUN and CRE. The liver and kidney were collected for analysis of histopathologic changes and CYP450 expression and activity. Vacuolization of cytoplasm in liver cells, swelling in kidney tubular cells, increased levels of ALT, AST, BUN, and CRE, and alteration in the expression and activity of CYP450 were observed in the high-dose group after 4 weeks of treatment. However, all aloperine-induced damages were recovered to a certain degree after maintained without aloperine for 1 week, and fully recovered after maintained without aloperine for 4 weeks. These findings suggested that aloperine regulated the expression of CYP450, which was possibly involved in aloperine-induced reversible toxicity in mouse liver and kidney tissues.


Assuntos
Anti-Hipertensivos/efeitos adversos , Antineoplásicos/efeitos adversos , Sistema Enzimático do Citocromo P-450/metabolismo , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Piperidinas/efeitos adversos , Animais , Feminino , Injeções Intraperitoneais/veterinária , Rim/patologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Substâncias Protetoras/metabolismo , Quinolizidinas , Sophora/química
6.
J Med Internet Res ; 22(2): e14410, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32130124

RESUMO

BACKGROUND: Patient portals are now widely available and increasingly adopted by patients and providers. Despite the growing research interest in patient portal adoption, there is a lack of follow-up studies describing the following: whether patients use portals actively; how frequently they use distinct portal functions; and, consequently, what the effects of using them are, the understanding of which is paramount to maximizing the potential of patient portals to enhance care delivery. OBJECTIVE: To investigate the characteristics of primary care patients using different patient portal functions and the impact of various portal usage behaviors on patients' primary care service utilization and appointment adherence. METHODS: A retrospective, observational study using a large dataset of 46,544 primary care patients from University of Florida Health was conducted. Patient portal users were defined as patients who adopted a portal, and adoption was defined as the status that a portal account was opened and kept activated during the study period. Then, users were further classified into different user subgroups based on their portal usage of messaging, laboratory, appointment, and medication functions. The intervention outcomes were the rates of primary care office visits categorized as arrived, telephone encounters, cancellations, and no-shows per quarter as the measures of primary care service utilization and appointment adherence. Generalized linear models with a panel difference-in-differences study design were then developed to estimate the rate ratios between the users and the matched nonusers of the four measurements with an observational window of up to 10 quarters after portal adoption. RESULTS: Interestingly, a high propensity to adopt patient portals does not necessarily imply more frequent use of portals. In particular, the number of active health problems one had was significantly negatively associated with portal adoption (odds ratios [ORs] 0.57-0.86, 95% CIs 0.51-0.94, all P<.001) but was positively associated with portal usage (ORs 1.37-1.76, 95% CIs 1.11-2.22, all P≤.01). The same was true for being enrolled in Medicare for portal adoption (OR 0.47, 95% CI 0.41-0.54, P<.001) and message usage (OR 1.44, 95% CI 1.03-2.03, P=.04). On the impact of portal usage, the effects were time-dependent and specific to the user subgroup. The most salient change was the improvement in appointment adherence, and patients who used messaging and laboratory functions more often exhibited a larger reduction in no-shows compared to other user subgroups. CONCLUSIONS: Patients differ in their portal adoption and usage behaviors, and the portal usage effects are heterogeneous and dynamic. However, there exists a lack of match in the patient portal market where patients who benefit the most from patient portals are not active portal adopters. Our findings suggest that health care delivery planners and administrators should remove the barriers of adoption for the portal beneficiaries; in addition, they should incorporate the impact of portal usage into care coordination and workflow design, ultimately aligning patients' and providers' needs and functionalities to effectively deliver patient-centric care.


Assuntos
Agendamento de Consultas , Portais do Paciente/normas , Atenção Primária à Saúde/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
J Ethnopharmacol ; 213: 376-383, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29102763

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sophora alopecuroides L., a traditional Chinese herb, has been widely used to treat numerous diseases throughout China. Quinolizidine alkaloids were identified as active components in Sophora alopecuroides L., and Sophoridine (SRI) is the major component in the Quinolizidine alkaloids. AIM OF THE STUDY: To investigate the toxic effects of SRI in rat liver BRL-3A cells and to explore potential ROS-related mechanisms. MATERIALS AND METHODS: Cell viability, cytotoxicity, apoptosis, intracellular generation of ROS, GSH/GSSG ratio and levels of proteins in mitochondria apoptosis pathway were analyzed. RESULTS: Our data indicated that SRI could suppress BRL-3A cells viability in a concentration- and time-dependent manner and increase cytotoxicity, ROS accumulation and cell apoptosis in a concentration-dependent manner. Expressions and activities of apoptotic related proteins were upregulated, whereas expression of Bcl-2 was downregulated after treatment. Furthermore, level of H2O2 was increased, whereas level of Superoxide was not changed after treatment. Moreover, the antioxidant N-acetylcysteine reversed SRI-induced apoptosis and ROS accumulation. CONCLUSION: Our data suggest that SRI promotes rat liver BRL-3A cells apoptosis by increasing intracellular ROS accumulation.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Fígado/citologia , Fígado/efeitos dos fármacos , Quinolizinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Alcaloides/antagonistas & inibidores , Animais , Proteínas Reguladoras de Apoptose/biossíntese , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos , Quinolizinas/antagonistas & inibidores , Ratos , Proteína X Associada a bcl-2/biossíntese , Matrinas
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