Navegando por Autor "Bueno, Lilian Lacerda"
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Item Antigenicity of a whole parasite vaccine as promising candidate against canine leishmaniasis.(2008) Giunchetti, Rodolfo Cordeiro; Reis, Alexandre Barbosa; Lemos, Denise da Silveira; Martins Filho, Olindo Assis; Oliveira, Rodrigo Corrêa de; Bethony, Jeffrey Michael; Vale, André Macedo; Quetz, Josiane da Silva; Bueno, Lilian Lacerda; Silva, João Carlos França da; Nascimento, Evaldo do; Mayrink, Wilson; Fujiwara, Ricardo ToshioHuman visceral leishmaniasis, one of the most important zoonoses, is caused by the protozoaLeishmania chagasi(syn. L. infantum ) and is present as a fatal disease common in South America and Europe where dogs and wild canids are the main reservoirs. A vaccine against visceral leishmaniasis would be an important tool in the control of this disease in dogs. Although the current strategies for vac-cination against leishmaniasis are based on the use of recombinant antigens, killed vaccines are still attractive in terms of stability of their biochemical composition and antigenicity, cost, and safety. Here we evaluate the immunogenicity of a whole parasite vaccine as a prom-ising candidate against canine leishmaniasis, demonstrated by cellular reactivity, changes in the cellular profile of the peripheral blood and by the differential production of immunoglobulins. Our results showed that immunization elicited mainly a strong cellular reactivity and increase in T-lymphocytes, particularly the subpopulation CD8 + that would be related to the control of tissue parasitism. In addi-tion, a higher production of anti- Leishmania total IgG, characterized by mixed isotypes profile (IgG1 and IgG2), was demonstrated.Item Exploring drug repositioning for leishmaniasis treatment : ivermectin plus polymeric micelles induce immunological response and protection against tegumentary leishmaniasis.(2023) Freitas, Camila Simões de; Lage, Daniela Pagliara; Machado, Amanda Sanchez; Vale, Danniele Luciana; Martins, Vívian Tamietti; Cardoso, Jamille Mirelle de Oliveira; Silva, João Augusto Oliveira da; Reis, Thiago Alves Rosa dos; Tavares, Grasiele de Sousa Vieira; Ramos, Fernanda Fonseca; Ribeiro, Fernanda Ludolf; Pereira, Isabela Amorim Gonçalves; Bandeira, Raquel Soares; Fujiwara, Ricardo Toshio; Bueno, Lilian Lacerda; Roatt, Bruno Mendes; Chávez Fumagalli, Miguel Angel; Coelho, Eduardo Antônio FerrazLeishmania amazonensis can cause a wide spectrum of the clinical manifestations of leishmaniasis in humans. The development of new therapeutics is a long and expensive task; in this context, drug repositioning could be considered a strategy to identify new biological actions of known products. In the present study, ivermectin (IVE) was tested against distinct Leishmania species able to cause disease in humans. In vitro experiments showed that IVE was effective to reduce the infection degree and parasite load in Leishmania donovani- and L. amazonensisinfected macrophages that were treated with it. In addition, using the culture supernatant of treated macrophages, higher production of IFN-γ and IL-12 and lower levels of IL-4 and IL-10 were found. Then, IVE was used in a pure form or incorporated into Poloxamer 407-based polymeric micelles (IVE/M) for the treatment of L. amazonensis-infected BALB/c mice. Animals (n = 16 per group) were infected and later received saline, empty micelles, amphotericin B (AmpB), IVE, or IVE/M. They were euthanized at one (n = 8 per group) and 30 (n = 8 per group) days after treatment and, in both endpoints, immunological, parasitological, and biochemical evaluations were performed. Results showed that both IVE and IVE/M induced higher levels of IFN-γ, IL-12, GM-CSF, nitrite, and IgG2a antibodies, as well as higher IFN-γ expression evaluated by RT-qPCR in spleen cell cultures. Such animals showed low organic toxicity, as well as significant reductions in the lesion’s average diameter and parasite load in their infected tissue, spleen, liver, and draining lymph node. The efficacy was maintained 30 days post-therapy, while control mice developed a polarized Th2-type response and high parasite load. In this context, IVE could be considered as a new candidate to be applied in future studies for the treatment against distinct Leishmania species.Item Immunodiagnosis of canine visceral leishmaniasis using mimotope peptides selected from phage is played combinatorial libraries.(2015) Machado, Christina Monerat Toledo; Ávila, Ricardo Andrez Machado de; NGuyen, Christophe; Granier, Claude; Bueno, Lilian Lacerda; Carneiro, Cláudia Martins; Souza, Daniel Menezes; Carneiro, Rubens Antônio; Chávez Orlórtegui, Carlos; Fujiwara, ToshioELISA and RIFI are currently used for serodiagnosis of canine visceral leishmaniasis (CVL). The accuracy of these tests is controversial in endemic areas where canine infections by Trypanosoma cruzi may occur.We evaluated the usefulness of synthetic peptides that were selected through phage display technique in the serodiagnosis of CVL. Peptides were chosen based on their ability to bind to IgGs purified from infected dogs pooled sera. We selected three phage clones that reacted only with those IgGs. Peptideswere synthesized, polymerizedwith glutaraldehyde, and used as antigens in ELISA assays. Each individual peptide or a mix of them was reactive with infected dogs serum. The assay was highly sensitive and specific when compared to soluble Leishmania antigen that showed cross-reactivity with anti-T. cruzi IgGs. Our results demonstrate that phage display technique is useful for selection of peptides that may represent valuable synthetic antigens for an improved serodiagnosis of CVLItem Immunogenicity in dogs of three recombinant antigens (TSA, LeiF and LmSTI1) potential vaccine for canine visceral leishmaniasis.(2005) Fujiwara, Ricardo Toshio; Vale, André Macedo; Silva, João Carlos França da; Costa, Roberto Teodoro da; Quetz, Josiane da Silva; Martins Filho, Olindo Assis; Reis, Alexandre Barbosa; Oliveira, Rodrigo Corrêa de; Coelho, George Luiz Lins Machado; Bueno, Lilian Lacerda; Bethony, Jeffrey Michael; Frank, Glen; Nascimento, Evaldo do; Genaro, Odair; Mayrink, Wilson; Reed, Steven G.; Campos Neto, AntonioControl of canine visceral leishmaniasis (VL) remains a difficult and serious problem mostly because there is no reliable and effective vaccine available to prevent this disease. A mixture of three recombinant leishmanial antigens (TSA, LeIF and LmSTI1) encoded by three genes highly conserved in the Leishmania genus have been shown to induce excellent protection against infection in both murine and simian models of cutaneous leishmaniasis. A human clinical trial with these antigens is currently underway. Because of the high degree of conservation, these antigens might be useful vaccine candidates for VL as well. In the present study, using the dog model of the visceral disease, we evaluated the immunogenicity of these three antigens formulated with two different adjuvants, MPL-SE® and AdjuPrime®. The results were compared with a whole parasite vaccine formulated with BCG as the adjuvant. In order to investigate if sensitization with the recombinant antigens would result in recognition of the corresponding native parasite antigens upon infection, the animals were exposed for four weeks after the termination of the immunization protocol with the recombinant antigens to a low number of L. chagasi promastigotes, an etiological agent of VL. Immune response was evaluated by quantitative ELISA in the animal sera before and after exposure to the viable parasites. Both antigen specific IgG1 and IgG2 antibody levels were measured. Immunization of dogs with the recombinant antigens formulated in either MPL-SE® or AdjuPrime® resulted in high antibody levels particularly to LmSTI1. In addition, this immunization although to low levels, resulted in the development of antibody response to the whole parasite lysate. Importantly, experimental exposure with low numbers of culture forms of L. chagasi promastigotes caused a clear boost in the immune response to both the recombinant antigens and the corresponding native molecules. The boost response was predominantly of the IgG2 isotype in animals primed with the recombinant antigens plus MPL-SE®. In contrast, animals primed with the recombinant antigens formulated in AdjuPrime® as well as animals vaccinated with crude antigen preparation responded with mixed IgG1/IgG2 isotypes. These results point to the possible use of this antigen cocktail formulated with the adjuvant MPL-SE® in efficacy field trials against canine VL.Item Nanoformulations with Leishmania braziliensis antigens triggered controlled parasite burden in vaccinated golden hamster (Mesocricetus auratus) against visceral leishmaniasis.(2022) Ottino, Jennifer; Leite, Jaqueline Costa; Melo Júnior, Otoni Alves de Oliveira; Cabrera González, Marco Antonio; Carvalho, Tatiane Furtado de; Garcia, Giani Martins; Batista, Maurício Azevedo; Silveira, Patrícia; Cardoso, Mariana Santos; Bueno, Lilian Lacerda; Fujiwara, Ricardo Toshio; Santos, Renato Lima; Paes, Paulo Ricardo de Oliveira; Lemos, Denise da Silveira; Martins Filho, Olindo Assis; Galdino, Alexsandro Sobreira; Chávez Fumagalli, Miguel Angel; Dutra, Walderez Ornelas; Mosqueira, Vanessa Carla Furtado; Giunchetti, Rodolfo CordeiroLeishmaniasis is a widespread vector-borne disease in Brazil, with Leishmania (Leishmania) infantum as the primary etiological agent of visceral leishmaniasis (VL). Dogs are considered the main reservoir of this parasite, whose treatment in Brazil is restricted to the use of veterinary medicines, which do not promote a parasitological cure. Therefore, efficient vaccine development is the best approach to Canine Visceral Leishmaniasis (CVL) control. With this in mind, this study used hamsters (Mesocricetus auratus) as an experimental model in an anti-Leishmania preclinical vaccine trial to evaluate the safety, antigenicity, humoral response, and effects on tissue parasite load. Two novel formulations of nanoparticles made from poly(D, L-lactic) acid (PLA) polymer loading Leishmania braziliensis crude antigen (LB) exhibiting two different particle sizes were utilized: LBPSmG (570 nm) and LBPSmP (388 nm). The results showed that the nanoparticles were safe and harmless to hamsters and were antigenic with the induction in LBSap, LBPSmG, and LBPSmG groups of total anti-Leishmania IgG antibodies 30 days after challenge, which persists 200 days in LBSap and LBPSmP. At the same time, a less pronounced hepatosplenomegaly in LBSap, LBPSmG, and LBPSmP was found when compared to control groups, as well as a less pronounced inflammatory infiltrate and granuloma formation in the spleen. Furthermore, significant reductions of 84%, 81%, and 90% were observed in spleen parasite burden accessed by qPCR in the LBSap, LBPSmG, and LBPSmP groups, respectively. In this way, LBSap, LBPSmG, and LBPSmP formulations showed better results in vaccinated and L. infantum-challenged animals in further reducing parasitic load in the spleen and attenuating lesions in liver and splenic tissues. This results in safe, harmless nanoformulation vaccines with significant immunogenic and infection control potential. In addition, animals vaccinated with LBPSmP had an overall reduction in parasite burden in the spleen, indicating that a smaller nanoparticle could be more efficient in targeting antigen-presenting cells.Item Vaccination with formulation of nanoparticles loaded with Leishmania amazonensis antigens confers protection against experimental visceral leishmaniasis in hamster.(2023) Cabrera González, Marco Antonio; Gonçalves, Ana Alice Maia; Ottino, Jennifer; Leite, Jaqueline Costa; Resende, Lucilene Aparecida; Melo Júnior, Otoni Alves de Oliveira; Silveira, Patricia; Cardoso, Mariana Santos; Fujiwara, Ricardo Toshio; Bueno, Lilian Lacerda; Santos, Renato Lima; Carvalho, Tatiane Furtado de; Garcia, Giani Martins; Paes, Paulo Ricardo de Oliveira; Galdino, Alexsandro Sobreira; Chávez Fumagalli, Miguel Angel; Melo, Marilia Martins; Lemos, Denise da Silveira; Martins Filho, Olindo Assis; Dutra, Walderez Ornelas; Mosqueira, Vanessa Carla Furtado; Giunchetti, Rodolfo CordeiroVisceral leishmaniasis (VL) is a fatal disease caused by the protozoa Leishmania infantum for which dogs are the main reservoirs. A vaccine against canine visceral leishmaniasis (CVL) could be an important tool in the control of human and CVL by reducing the infection pressure of L. infantum. Despite the CVL vaccine available on the market, the Brazilian Ministry of Health did not implement the use of it in their control programs. In this sense, there is an urgent need to develop more efficient vaccines. In this study, the association between two polymeric nanoformulations, (poly (D, L-lactic) acid (PLA) polymer) loading Leishmania amazonensis antigens, was evaluated as a potential immunobiological agent against VL using golden hamsters as an experimental model. The results indicated that no significant adverse reactions were observed in animals vaccinated with LAPSmP. LAPSmP presented similar levels of total anti-Leishmania IgG as compared to LAPSmG. The LAPSmP and LAPSmG groups showed an intense reduction in liver and spleen parasitic load by qPCR. The LAPSmP and LAPSmG vaccines showed exceptional results, indicating that they may be promising candidates as a VL vaccine.