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1.
PLoS Negl Trop Dis ; 18(5): e0012126, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38743668

RESUMO

The parasite Leishmania (Viannia) braziliensis is widely distributed in Brazil and is one of the main species associated with human cases of different forms of tegumentary leishmaniasis (TL) such as cutaneous leishmaniasis (CL) and mucosal leishmaniasis (ML). The mechanisms underlying the pathogenesis of TL are still not fully understood, but it is known that factors related to the host and the parasite act in a synergistic and relevant way to direct the response to the infection. In the host, macrophages have a central connection with the parasite and play a fundamental role in the defense of the organism due to their ability to destroy intracellular parasites and present antigens. In the parasite, some intrinsic factors related to the species or even the strain analyzed are fundamental for the outcome of the disease. One of them is the presence of Leishmania RNA Virus 1 (LRV1), an endosymbiont virus that parasitizes some species of Leishmania that triggers a cascade of signals leading to a more severe TL phenotype, such as ML. One of the strategies for understanding factors associated with the immune response generated after Leishmania/host interaction is through the analysis of molecular patterns after infection. Thus, the gene expression profile in human monocyte-derived macrophages obtained from healthy donors infected in vitro with L. braziliensis positive (LbLRV1+) and negative (LbLRV1-) for LRV1 was evaluated. For this, the microarray assay was used and 162 differentially expressed genes were identified in the comparison LbLRV1+ vs. LbLRV1-, 126 upregulated genes for the type I and II interferons (IFN) signaling pathway, oligoadenylate synthase OAS/RNAse L, non-genomic actions of vitamin D3 and RIG-I type receptors, and 36 down-regulated. The top 10 downregulated genes along with the top 10 upregulated genes were considered for analysis. Type I interferon (IFNI)- and OAS-related pathways results were validated by RT-qPCR and Th1/Th2/Th17 cytokines were analyzed by Cytometric Bead Array (CBA) and enzyme-linked immunosorbent assay (ELISA). The microarray results validated by RT-qPCR showed differential expression of genes related to IFNI-mediated pathways with overexpression of different genes in cells infected with LbLRV1+ compared to LbLRV1- and to the control. No significant differences were found in cytokine levels between LbLRV1+ vs. LbLRV1- and control. The data suggest the activation of gene signaling pathways associated with the presence of LRV1 has not yet been reported so far. This study demonstrates, for the first time, the activation of the OAS/RNase L signaling pathway and the non-genomic actions of vitamin D3 when comparing infections with LbLRV1+ versus LbLRV1- and the control. This finding emphasizes the role of LRV1 in directing the host's immune response after infection, underlining the importance of identifying LRV1 in patients with TL to assess disease progression.


Assuntos
Leishmania braziliensis , Leishmaniavirus , Macrófagos , Humanos , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Macrófagos/imunologia , Macrófagos/virologia , Leishmaniavirus/genética , Perfilação da Expressão Gênica , Leishmaniose Cutânea/imunologia , Brasil , Simbiose , Citocinas/metabolismo , Citocinas/genética , Transcriptoma , Leishmaniose Mucocutânea/imunologia , Leishmaniose Mucocutânea/parasitologia
2.
Exp Parasitol ; 240: 108338, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35917898

RESUMO

American cutaneous leishmaniasis (ACL) may present different clinical manifestations, immune and therapeutic responses, depending on the Leishmania species, as well as inoculum size and factors inherent to the affected individual. Thus, the aim of this study was to carry out clinical-therapeutic follow-up of Brazilian patients with ACL caused by different Leishmania species. Between 2015 and 2018, patients with ACL from Amazonas and Pernambuco states (Brazil) were submitted to blood collection before and after treatment. The qPCR technique was used to quantify the parasite load. To identify the Leishmania species, one of the following techniques was employed: a conventional PCR performed from biopsy or blood DNA, followed by sequencing; or Multilocus Enzyme Electrophoresis from Leishmania isolated from biopsy/aspirated lesion. A total of 10.8% (23/213) of the patients included in positive cases were followed-up. All 23 patients were clinically and epidemiologically compatible with ACL and were also positive in parasitological tests (86.96%), molecular tests (73.91%) or both (60.87%). Seventeen samples collected before treatment and 11 collected after treatment were positive in the qPCR assay, with a mean parasite load (MPL) of 38.33 fg/µL and 11.81 fg/µL, respectively. Eight samples were positive in both collections. Thirteen patients (56.52%) were clinically cured (wound healing). Ten patients (43.47%) were not clinically cured at the time of return with the attending physician. Identification of Leishmania species was carried out in samples from nine patients, and six were identified as L. (Viannia) braziliensis, 2 as L (Viannia) guyanensis and 1 as L (Leishmania) amazonensis. One patient infected with L. guyanensis and other with L. braziliensis were not clinically cured and increased the mean parasite load after treatment. The data obtained from the followed-up patients and the relationship between clinical evolution and the infecting species demonstrate the need to understand its etiology to define the effective therapeutic protocol.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Leishmaniose Mucocutânea , Brasil/epidemiologia , Seguimentos , Humanos , Leishmania/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Leishmaniose Mucocutânea/parasitologia , Reação em Cadeia da Polimerase em Tempo Real
3.
Front Cell Infect Microbiol ; 12: 824968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242720

RESUMO

Leishmania (Viannia) braziliensis is the main etiological agent of cutaneous and mucocutaneous leishmaniasis in Latin America. Non-ulcerated atypical tegumentary leishmaniasis cases caused by L. braziliensis have been reported in several regions of the American continent, including the Xacriabá indigenous reserve in São João das Missões/Minas Gerais, Brazil. Parasites isolated from these atypical clinical lesions are resistant to antimony-based therapeutics. In the present study, proteins displaying differential abundance in two strains of L. braziliensis isolated from patients with atypical lesions compared with four strains isolated from patients with typical lesions were identified using a quantitative proteomics approach based on tandem mass tag labeling (TMT) and mass spectrometry. A total of 532 (P<0.05) differentially abundant proteins were identified (298 upregulated and 234 downregulated) in strains from atypical lesions compared to strains from typical lesions. Prominent positively regulated proteins in atypical strains included those that may confer greater survival inside macrophages, proteins related to antimony resistance, and proteins associated with higher peroxidase activity. Additionally, we identified proteins showing potential as new drug and vaccine targets. Our findings contribute to the characterization of these intriguing L. braziliensis strains and provide a novel perspective on Atypical Cutaneous Leishmaniasis (ACL) cases that have been associated with therapeutic failures.


Assuntos
Leishmania braziliensis , Leishmaniose Cutânea , Leishmaniose Mucocutânea , Antimônio/farmacologia , Antimônio/uso terapêutico , Brasil , Humanos , Leishmaniose Cutânea/parasitologia , Leishmaniose Mucocutânea/parasitologia , Pele
4.
Sci Rep ; 11(1): 15323, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321495

RESUMO

Lutzomyia umbratilis is the main vector of Leishmania guyanensis in the Brazilian Amazon and in neighboring countries. Previous biological and molecular investigations have revealed significant differences between L. umbratilis populations from the central Brazilian Amazon region. Here, a phylogeographic survey of L. umbratilis populations collected from nine localities in the Brazilian Amazon was conducted using two mitochondrial genes. Statistical analyses focused on population genetics, phylogenetic relationships and species delimitations. COI genetic diversity was very high, whereas Cytb diversity was moderate. COI genealogical haplotypes, population structure and phylogenetic analyses identified a deep genetic differentiation and three main genetic groups. Cytb showed a shallower genetic structure, two main haplogroups and poorly resolved phylogenetic trees. These findings, allied to absence of isolation by distance, support the hypothesis that the Amazon and Negro Rivers and interfluves are the main evolutionary forces driving L. umbratilis diversification. The main three genetic groups observed represent three evolutionary lineages, possibly species. The first lineage occurs north of the Amazon River and east of Negro River, where Le. guyanensis transmission is intense, implying that L. umbratilis is an important vector there. The second lineage is in the interfluve between north of Amazon River and west of Negro River, an area reported to be free of Le. guyanensis transmission. The third lineage, first recorded in this study, is in the interfluve between south of Amazonas River and west of Madeira River, and its involvement in the transmission of this parasite remains to be elucidated.


Assuntos
Evolução Biológica , Insetos Vetores/genética , Leishmania guyanensis/patogenicidade , Leishmaniose Mucocutânea/transmissão , Filogenia , Psychodidae/genética , Animais , Brasil/epidemiologia , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Expressão Gênica , Variação Genética , Haplótipos , Humanos , Proteínas de Insetos/genética , Insetos Vetores/classificação , Leishmania guyanensis/crescimento & desenvolvimento , Leishmaniose Mucocutânea/epidemiologia , Leishmaniose Mucocutânea/parasitologia , Mitocôndrias/enzimologia , Mitocôndrias/genética , Filogeografia , Psychodidae/classificação , Rios/parasitologia
5.
PLoS One ; 16(5): e0251956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34043671

RESUMO

Immunological tests may represent valuable tools for the diagnosis of human tegumentary leishmaniasis (TL) due to their simple execution, less invasive nature and potential use as a point-of-care test. Indeed, several antigenic targets have been used with the aim of improving the restricted scenario for TL-diagnosis. We performed a worldwide systematic review to identify antigenic targets that have been evaluated for the main clinical forms of TL, such as cutaneous (CL) and mucosal (ML) leishmaniasis. Included were original studies evaluating the sensitivity and specificity of immunological tests for human-TL, CL and/or ML diagnosis using purified or recombinant proteins, synthetic peptides or polyclonal or monoclonal antibodies to detect Leishmania-specific antibodies or antigens. The review methodology followed PRISMA guidelines and all selected studies were evaluated in accordance with QUADAS-2. Thirty-eight original studies from four databases fulfilled the selection criteria. A total of 79 antigens were evaluated for the detection of antibodies as a diagnostic for TL, CL and/or ML by ELISA. Furthermore, three antibodies were evaluated for the detection of antigen by immunochromatographic test (ICT) and immunohistochemistry (IHC) for CL-diagnosis. Several antigenic targets showed 100% of sensitivity and specificity, suggesting potential use for TL-diagnosis in its different clinical manifestations. However, a high number of proof-of-concept studies reinforce the need for further analysis aimed at verifying true diagnostic accuracy in clinical practice.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/sangue , Leishmania/imunologia , Leishmaniose Tegumentar Difusa/diagnóstico , Leishmaniose Mucocutânea/diagnóstico , Antígenos de Protozoários/classificação , Antígenos de Protozoários/imunologia , Cromatografia de Afinidade/normas , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Imuno-Histoquímica/normas , Leishmaniose Tegumentar Difusa/imunologia , Leishmaniose Tegumentar Difusa/parasitologia , Leishmaniose Mucocutânea/imunologia , Leishmaniose Mucocutânea/parasitologia , Testes Imediatos/normas , Guias de Prática Clínica como Assunto , Sensibilidade e Especificidade
6.
Am J Trop Med Hyg ; 104(4): 1326-1334, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432903

RESUMO

Isolates from 475 cutaneous leishmaniasis (CL) patients from three endemic regions were studied by three typing techniques. The molecular analysis from lesion scrapings based on hsp70 PCR-restriction fragment length polymorphism (RFLP) showed that 78.1% (371/475) restriction patterns corresponded to Leishmania (Viannia) panamensis, 19% (90/475) to Leishmania (Viannia) guyanensis, and 3.0% (14/475) to Leishmania (Viannia) braziliensis. Promastigotes isolated by culture from lesions of 228 patients (48.0%, 228/475) were identified by multi-locus enzyme electrophoresis. Of them, 95.2% (217/228) were typified as L. (V.) panamensis, 1.3% (3/228) as L. (V.) guyanensis, 2.2% (5/228) as L. (V.) braziliensis, and 1.3% (3/228) as hybrids (L. [V.] braziliensis/L. [V.] panamensis). However, a partial sequencing analysis of the hsp70 gene from 77 selected samples showed 16.9% (13/77) typified as L. (V.) panamensis, 68.8% (53/77) as Leishmania (V.) sp., 1, 3.9% (3/77) as L. (V.) guyanensis, 1.3% (1/77) as L. (V.) braziliensis outlier, 2.6% (2/77) as Leishmania (Viannia) naiffi, 2.6% as (2/77) Leishmania (V.) sp., and 2 and 3.9% (3/77) hybrid isolates of L. (V.) braziliensis/L. (V.) guyanensis. These results confirm L. (V.) panamensis as the predominant species and cause of CL lesions in Panama and that L. (V.) guyanensis, L. (V.) braziliensis, and L. (V.) naiffi are circulating to a lower degree. Furthermore, the determination of parasite isolates belonging to atypical clusters and hybrid isolates suggests the circulation of genetic variants with important implications for the epidemiology and clinical follow-up of CL in Panama. No evidence of the existence of parasites of the Leishmania (Leishmania) mexicana complex in Panamanian territory was found in this study.


Assuntos
DNA de Protozoário/análise , Variação Genética , Leishmania/genética , Leishmaniose Cutânea/parasitologia , Impressões Digitais de DNA/métodos , DNA de Protozoário/genética , Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Mucocutânea/epidemiologia , Leishmaniose Mucocutânea/parasitologia , Panamá/epidemiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
7.
Int J Infect Dis ; 97: 204-207, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32505874

RESUMO

INTRODUCTION: Mucocutaneous leishmaniasis (MCL) is a complication of tegumentary leishmaniasis, causing potentially life-threatening lesions in the ear, nose, and throat (ENT) region, and most commonly due to Leishmania (Viannia) braziliensis. We report a case of relapsing MCL in an Italian traveler returning from Argentina. CASE DESCRIPTION: A 65-year-old Italian male patient with chronic kidney disease, arterial hypertension, prostatic hypertrophy, and type-2 diabetes mellitus was referred for severe relapsing MCL acquired in Argentina. ENT examination showed severe diffuse pharyngolaryngeal edema and erythema, partially obstructing the airways. A nasopharyngeal biopsy revealed a lymphoplasmacytic inflammation and presence of Leishmania amastigotes, subsequently identified as L. (V.) braziliensis by hsp70 PCR-RFLP analysis and sequencing. Despite receiving four courses of liposomal amphotericine B (L-AmB) and two courses of miltefosine over a 2-year period, the patient presented recurrence of symptoms a few months after the end of each course. After the patient was referred to us, a combined treatment was started with intravenous pentamidine 4 mg/kg on alternate days for 10 doses, followed by one dose per week for an additional seven doses, intralesional meglumine antimoniate on the nasal lesion once per week for six doses, oral azoles for three months, and aerosolized L-AmB on alternate days for three months. The treatment led to regression of mucosal lesions and respiratory symptoms. Renal function temporarily worsened, and the addition of insulin was required to maintain glycemic compensation after pentamidine discontinuation. CONCLUSIONS: This case highlights the difficulties in managing a life-threatening refractory case of MCL in an Italian traveler with multiple comorbidities. Even though parenteral antimonial derivatives are traditionally considered the treatment of choice for MCL, they are relatively contraindicated in cases of chronic kidney disease.The required dose adjustment in cases of impaired renal function is unknown, therefore the use of alternative drugs is recommended. This case was resolved with combination treatment, including aerosolized L-AmB, which had never been used before for MCL.


Assuntos
Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Azóis/administração & dosagem , Leishmaniose Mucocutânea/tratamento farmacológico , Antimoniato de Meglumina/administração & dosagem , Pentamidina/administração & dosagem , Administração Intravenosa , Idoso , Argentina , Quimioterapia Combinada , Humanos , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/fisiologia , Leishmaniose Mucocutânea/parasitologia , Masculino , Recidiva
8.
PLoS One ; 15(5): e0232829, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32379842

RESUMO

The diagnosis of American tegumentary leishmaniasis (ATL) still requires the design of more effective tools. Leishmania (Viannia) braziliensis is the causal agent of the 90% of Argentinean ATL cases. Considering the current knowledge, an ELISA based crude antigen (CA) for the diagnosis was designed. Ninety-nine subjects diagnosed as ATL, 27 as no-ATL, and 84 donors from non-ATL-endemic areas were included in this study. The current ATL diagnosis was based four techniques, dermal smear microscopic examination (parasitological test), PCR, Leishmanin skin test, and clinical records. We obtained CA extracts from promastigotes and amastigotes from macrophage cultures of different zymodemes of endemic Leishmania species circulating in the study area. Crude antigens from the 'local' main zymodeme of L. (V.) braziliensis showed the highest reactivity against anti-Leishmania antibodies compared to the other included species. The CA of amastigotes of this zymodeme was 3.4 fold more reactive than promastigotes one. Moreover, amastigote-membrane CA (MCA) were 3.6 fold more reactive than the soluble antigens. The MCA-ELISA reached a sensitivity and specificity of 98% (CI = 94.7%-100%) and 63.6% (53.9-73.1), respectively. When anti-Trypanosoma cruzi reactive sera were excluded, the specificity reached 98.4% (94.4-100), while the sensitivity was similar, with a positive predictive value (PV) of 98.6% (94.6-100) and negative PV of 96.3% (91.6-100). The performance of the MCA-ELISA results strongly contribute to the final diagnostic decision, since a non-reactive serological result almost discards the suspected ATL, because of its high negative PV. The developed MCA-ELISA showed a high diagnostic performance, which makes it a good candidate for ATL diagnosis, for seroprevalence studies, or for monitoring treatments efficacy.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Membrana Celular/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/diagnóstico , Afinidade de Anticorpos , Especificidade de Anticorpos , Argentina/epidemiologia , Doadores de Sangue , Doenças Endêmicas , Humanos , Leishmania braziliensis/crescimento & desenvolvimento , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Mucocutânea/sangue , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/parasitologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Trypanosoma cruzi/imunologia
9.
Epidemiol Serv Saude ; 29(1): e2018504, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32074196

RESUMO

OBJECTIVE: to investigate Leishmania species in a series of autochthonous cutaneous leishmaniasis (CL) cases in Amapá State, Brazilian Amazon. METHODS: this was a descriptive ecological study carried out from January-October/2018 at a reference center for CL diagnosis in Amapá; individuals with CL receiving care from January-May/2018 were recruited; clinical data and skin biopsies were obtained; from extracted DNA (phenol-chloroform) we amplified the hsp70-234 gene region (PCR) for nucleotide sequencing (Applied Biosystems: ABI3500XL). RESULTS: 38 individuals were interviewed, examined and diagnosed; men predominated (28/38; mean age=32.5±11.3); lesions (most ulcers: 37/38) measuring 0,4-10mm (34/38) and ≥11mm (4/38) were multiple in 20/38 individuals; diagnosis of L. braziliensis (1), L. naiffi (1), L. infantum (1), L. (Viannia) sp. (1), L. amazonensis (2) and L. guyanensis (32); individuals infected with L. guyanensis (32/38) lived in 9/10 municipalities represented in the sample, and 17/32 of these had multiple lesions. CONCLUSION: presence of Leishmania guyanensis predominated and was frequently associated with multiple lesions.


Assuntos
Leishmania guyanensis/isolamento & purificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Mucocutânea/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Humanos , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Vigilância da População , Distribuição por Sexo , Adulto Jovem
10.
Int. j. odontostomatol. (Print) ; 14(3): 342-347, 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1114904

RESUMO

La Leishmaniasis es un grupo de enfermedades transmitidas por vectores y causada por la Leishmania, un parásito intracelular, que se presenta de preferencia en regiones tropicales y subtropicales. Se manifiesta mediante un amplio rango de formas clínicas como la cutánea, mucocutánea, y visceral, dependiendo de la especie y respuesta inmunológica del paciente. Se presenta el caso de un hombre de 35 años que acudió derivado a Unidad de Estomatología del Hospital Señor del Milagro, Salta, Argentina, presentando en la cavidad oral lesión, granulomatosa, ulcerada, dolorosa a la palpación, única, en paladar blando, de tres meses de evolución. Se realizaron estudios serológicos, parasitológicos y PCR. Los ELISAs lisados, PCRs y cultivos de materiales de lesiones fueron positivos, confirmando diagnóstico de leishmaniasis mucocutánea. El paciente fue derivado al Servicio de Dermatología donde recibió tratamiento con Antimoniato de Meglumina, con repuesta clínica favorable. El conocimiento de las manifestaciones orales puede llevar al diagnóstico clínico de leishmaniasis mucocutánea por parte del odontólogo, pudiendo entregar un tratamiento oportuno y a la vez ayudar al paciente, evitando complicaciones de esta enfermedad.


Leishmaniasis is a group of vector-borne diseases caused by Leishmania, an intracellular parasite, which occurs preferentially in tropical and subtropical regions. It manifests itself through a wide range of clinical forms such as cutaneous, mucocutaneous, and visceral, depending on the species and the patient's immune response. We present a case of a 35-year-old man who was referred to the Stomatology Unit of the Señor del Milagro Hospital, Salta, Argentina, presenting in the oral cavity lesion, granulomatous, ulcerated, painful on palpation, unique, soft palate with three months of evolution. Serological, parasitological and PCR studies were performed. Lysed ELISAs, PCRs and cultures of lesion materials were positive, confirming diagnosis of mucocutaneous leishmaniasis. The patient was referred to the Dermatology Service where he received treatment with Meglumine Antimony, with favorable clinical response. The knowledge of the oral manifestations can lead to the clinical diagnosis of mucocutaneous leishmaniasis by the dentist, being able to provide timely treatment and at the same time help the patient, avoiding complications of this disease.


Assuntos
Humanos , Masculino , Adulto , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/parasitologia , Doenças da Boca/diagnóstico , Doenças da Boca/parasitologia , Paracoccidioidomicose/diagnóstico , Ensaio de Imunoadsorção Enzimática , Reação em Cadeia da Polimerase , Diagnóstico Diferencial , Histoplasmose/diagnóstico , Leishmania/isolamento & purificação , Mucosa Bucal/parasitologia
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