MARCIA DALASTRA LAURENTI
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Patologia, Faculdade de Medicina - Docente
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina - Líder
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- Th17 lymphocytes in atypical cutaneous leishmaniasis caused byLeishmania (L.) infantum chagasiin Central America(2020) FLORES, Gabriela Venicia Araujo; PACHECO, Carmen Maria Sandoval; OCHOA, Wilfredo Humberto Sosa; GOMES, Claudia Maria Castro; ZUNIGA, Concepcion; CORBETT, Carlos P.; LAURENTI, Marcia DalastraSkin lesions in nonulcerated cutaneous leishmaniasis (NUCL) caused byLeishmania (L.) infantum chagasiare characterized by a mononuclear inflammatory infiltrate in the dermis, which is composed mainly of lymphocytes, followed by macrophages, few plasma cells and epithelioid granulomas with mild tissue parasitism. Previous studies have shown that the main population of lymphocytes present in the dermal infiltrate is CD8(+)T cells, followed by CD4(+)T cells, which are correlated with IFN-gamma(+)cells. To improve the knowledge of cellular immune responses in NUCL, skin biopsies were submitted to immunohistochemistry using anti-ROR-gamma t, anti-IL-17, anti-IL-6, anti-TGF-beta, and anti-IL-23 antibodies to characterize the involvement of Th17 cells in the skin lesions of patients affected by NUCL. ROR-gamma t(+), IL-17(+), IL-6(+), TGF-beta(+)and IL-23(+)cells were observed in the dermal inflammatory infiltrate of NUCL skin lesions. A positive correlation between CD4(+)T-lymphocytes and ROR-gamma t(+)and IL-17(+)cells suggests that some of the CD4(+)T-lymphocytes in NUCL could be Th17 lymphocytes. Moreover, a positive correlation between ROR-gamma t(+)cells and TGF-beta(+), IL-6(+), IL-17(+)and IL-23(+)cells could indicate the role of these cytokines in the differentiation and maintenance of Th17 lymphocytes. Our findings improve knowledge of the pathogenesis of this rare and atypical clinical form of leishmaniasis.
- Macrophage Polarization in the Skin Lesion Caused by Neotropical Species of Leishmania sp(2021) PACHECO, Carmen M. Sandoval; V, Gabriela Araujo Flores; GONZALEZ, Kadir; GOMES, Claudia M. de Castro; PASSERO, Luiz F. D.; TOMOKANE, Thaise Y.; SOSA-OCHOA, Wilfredo; ZUNIGA, Concepcion; CALZADA, Jose; SALDANA, Azael; CORBETT, Carlos E. P.; SILVEIRA, Fernando T.; LAURENTI, Marcia D.Macrophages play important roles in the innate and acquired immune responses against Leishmania parasites. Depending on the subset and activation status, macrophages may eliminate intracellular parasites; however, these host cells also can offer a safe environment for Leishmania replication. In this sense, the fate of the parasite may be influenced by the phenotype of the infected macrophage, linked to the subtype of classically activated (M1) or alternatively activated (M2) macrophages. In the present study, M1 and M2 macrophage subsets were analyzed by double-staining immunohistochemistry in skin biopsies from patients with American cutaneous leishmaniasis (ACL) caused by L. (L.) amazonensis, L. (V.) braziliensis, L. (V.) panamensis ,and L. (L.) infantum chagasi. High number of M1 macrophages was detected in nonulcerated cutaneous leishmaniasis (NUCL) caused by L. (L.) infantum chagasi (M1=112 +/- 12, M2=43 +/- 12 cells/mm(2)). On the other side, high density of M2 macrophages was observed in the skin lesions of patients with anergic diffuse cutaneous leishmaniasis (ADCL) (M1=195 +/- 25, M2=616 +/- 114), followed by cases of localized cutaneous leishmaniasis (LCL) caused by L. (L.) amazonensis (M1=97 +/- 24, M2=219 +/- 29), L. (V.) panamensis (M1=71 +/- 14, M2=164 +/- 14), and L. (V.) braziliensis (M1=50 +/- 13, M2=53 +/- 10); however, low density of M2 macrophages was observed in NUCL. The data presented herein show the polarization of macrophages in skin lesions caused by different Leishmania species that may be related with the outcome of the disease.
- Can domestic dogs be considered a good reservoir of Leishmania (L.) infantum chagasi in an endemic area of nonulcerated cutaneous leishmaniasis in Southern Honduras?(2023) SEGURA, Gabriela Beatriz Rodriguez; OCHOA, Wilfredo Humberto Sosa; MATTA, Vania Lucia Ribeiro da; MARTINEZ, Mercedes; TERCERO, Carol Rodriguez; GONZALEZ, Raquel Romero; PACHECO, Carmen M. Sandoval; FLORES, Gabriela V. Araujo; SILVEIRA, Fernando Tobias; HENRIQUEZ, Maria Mercedes Rueda; LAURENTI, Marcia DalastraDogs are considered to be the main domestic reservoir associated with the transmission of Leishmania (L.) infantum chagasi to humans in endemic areas of visceral leishmaniasis in America. However, little is known about the role of canines as a source of infection in endemic areas of nonulcerated cutaneous leishmaniasis (NUCL). Therefore, the objective of the present study was to investigate the role of dogs as a possible reservoir of the parasite in Southern Honduras. Dogs (n = 107) living with individuals affected by NUCL were clinically examined and biological material was collected for parasitological and immunological diagnosis. Most animals showed a healthy appearance and a few presented slight weight loss (64%), alopecia (7%), onychogryphosis (5%) and skin lesions (1%). The overall seroprevalence of Leishmania infection based on the DDP (R) quick test and/or in-house ELISA serological test was 41%. The presence of the parasite's DNA was confirmed in 94% of the dogs; however, the average parasite load in the buffy coat was low at 6.09 parasites/mu L, ranging between 0.221 and 50.2. The skin of seropositive dogs examined by histopathology using paraffin sections stained by hematoxylin and immunohistochemistry did not show cutaneous lesions or parasite amastigotes. Based on the absence of parasites in the skin and the low parasite load detected in the buffy coat, it seems that the dog does not represent a good source of infection for the vector in the endemic area of NUCL transmission in Southern Honduras. Other domestic and/or wild animals should be investigated.
- Histopathological features of skin lesions in patients affected by non-ulcerated or atypical cutaneous leishmaniasis in Honduras, Central America(2018) PACHECO, Carmen Maria Sandoval; FLORES, Gabriela Venicia Araujo; FERREIRA, Aurea Favero; OCHOA, Wilfredo Sosa; MATTA, Vania Lucia Ribeiro da; VALERIANO, Concepcion Zuniga; CORBETT, Carlos Eduardo Pereira; LAURENTI, Marcia DalastraIn Honduras visceral leishmaniasis and non-ulcerated or atypical cutaneous leishmaniasis (NUCL) are caused by the species Leishmania (L.) infantum chagasi. NUCL is the most common clinical form in the southern regions of the country, mainly affecting the young. In view of the lack of knowledge about the pathogenesis of the disease pattern caused by L. (L) infantum chagasi in individuals affected by NUCL, the aim of the present study was to describe in detail the histopathological features of the skin lesion caused by the parasite. Biopsies from human NUCL lesions with a positive parasitological diagnosis were collected and processed using standard histological techniques. Paraffin sections stained by haematoxylin and eosin were used to examine the histopathological alterations seen in the skin. The lesions varied between 3 and 5 mm, and the majority of the patients (60%) had a single lesion. Lesions were more frequently seen in females (65%), with an average age of 33.4 years. Microscopically, the skin lesions were characterized by mononuclear inflammatory infiltrate in the dermis composed of lymphocytes, macrophages and a few plasma cells. The intensity of the infiltration varied from discrete to intense. In both cases, the parasitic infection was discrete. Granulomas were present in 60% of cases and were associated with intense inflammation. The data revealed by the histopathological alterations in the skin of individuals affected by NUCL suggest activation of a cellular immune response that potentially controls parasite spreading.
- Lipophosphoglycans from dermotropic Leishmania infantum are more pro-inflammatory than those from viscerotropic strains(2020) CARDOSO, Camila A.; V, Gabriela Araujo; SANDOVAL, Carmen M.; NOGUEIRA, Paula M.; ZUNIGA, Concepcion; SOSA-OCHOA, Wilfredo H.; LAURENTI, Marcia D.; SOARES, Rodrigo P.Although Leishmania infantum is well-known as the aethiological agent of visceral leishmaniasis (VL), in some Central American countries it may cause atypical non-ulcerated cutaneous leishmaniasis ( NUCL). However, the mechanisms favoring its establishment in the skin are still unknown. Lipophosphoglycan (LPG) is the major Leishmania multivirulence factor involved in parasite-host interaction. In the case of viscerotropic L. infantum, it causes an immunosuppression during the interaction with macrophages. Here, we investigated the biochemical and functional roles of LPGs from four dermotropic L. infantum strains from Honduras during in vitro interaction with murine macrophages. LPGs were extracted, purified and their repeat units analysed. They did not have side chains consisting of Gal(beta 1,4)Man(alpha 1)-PO4 common to all LPGs. Peritoneal macrophages from BALB/c and C57BL/6 were exposed to LPG for nitric oxide (NO) and cytokine (TNF-alpha and, IL-6) production. LPGs from dermotropic strains from Honduras triggered higher NO and cytokine levels compared to those from viscerotropic strains. In conclusion, LPGs from dermotropic strains are devoid of side-chains and exhibit high pro-inflammatory activity.
- Evaluation of Regulatory Immune Response in Skin Lesions of Patients Affected by Nonulcerated or Atypical Cutaneous Leishmaniasis in Honduras, Central America(2018) FLORES, Gabriela Venicia Araujo; PACHECO, Carmen Maria Sandoval; TOMOKANE, Thaise Yumie; OCHOA, Wilfredo Sosa; VALERIANO, Concepcion Zuniga; GOMES, Claudia Maria Castro; CORBETT, Carlos Eduardo Pereira; LAURENTI, Marcia DalastraIn Honduras, Leishmania (L.) infantum chagasi causes both visceral leishmaniasis (LV) and nonulcerated or atypical cutaneous leishmaniasis (NUCL). NUCL is characterized by mononuclear inflammatory infiltration of the dermis, composed mainly of lymphocytes followed by macrophages with discrete parasitism. Considering that little is known about the pathogenesis of NUCL, the aim of this study was to evaluate the regulatory response in situ in skin lesions of patients affected by NUCL. Biopsies (n = 20) from human cutaneous nonulcerative lesions were collected and processed by usual histological techniques. The in situ regulatory immune response was evaluated by immunohistochemistry using antihuman CD4, FoxP3, IL-10, and TGF-beta antibodies. CD4(+), FoxP3(+), TGF-beta(+), and IL-10(+) cells were observed in the dermis with inflammatory infiltration in all studied cases and at higher densities compared to the normal skin controls. A positive and strong correlation was observed between CD4(+) and FoxP3(+) cells, and a positive and moderate correlation was observed between FoxP3(+) and TGF-beta(+) but not with IL-10(+) cells. The data suggest that T regulatory FoxP3(+) cells and the regulatory cytokines, especially TGF-beta, play an important role in the immunopathogenesis of NUCL, modulating a cellular immune response in the skin, avoiding tissue damage, and leading to low tissue parasitic persistence.
- Evaluation of systemic immunity in atypical cutaneous leishmaniasis caused by Leishmania (L.) infantum chagasi(2022) LAURENTI, Marcia Dalastra; SOSA-OCHOA, Wilfredo; FLORES, Gabriela Venicia Araujo; PACHECO, Carmen Maria Sandoval; TOMOKANE, Thaise Yumie; OLIVEIRA, Luanda Mara da Silva; ZUNIGA, Concepcion; SILVEIRA, Fernando Tobias; CORBETT, Carlos Eduardo PereiraIn some central-American countries, Leishmania (L.) infantum chagasi infection can cause non-ulcerated or atypical cutaneous leishmaniasis (NUCL) in addition to the classic clinical form, visceral leishmaniasis (VL). Little is known about the host-parasite relationship that can contribute to the determination of one or another clinical form. The present study had the objective to evaluate the humoral and cellular immunity in the sera of individuals affected by NUCL to improve the comprehension of this atypical host-parasite interaction. Based on clinical and laboratory diagnosis, serum of 80 individuals was collected to evaluate the cytokines and immunoglobulins profile of NUCL (n = 47), VL patients (n = 5), and negative controls (n = 28). Cytokines were detected using Cytokine Bead Array (CBA) Human Th1/Th2/Th17 kit according to the manufacturer's instructions; class (IgG and IgM), and subclass of (IgG1 and IgG2) immunoglobulins was evaluated by ELISA using specific antigens. The concentration of TNF-alpha, IFN-gamma, IL-2 and IL-4 cytokines in NUCL, VL and control was present below the detection threshold of CBA kit. IL-6, IL-10 and IL-17A cytokines was lower in NUCL compared to LV patients. Regarding to immunoglobulins, NUCL patients produced 4.0 times more IgG than the control, while VL patients produced 6.6 times more; and IgM level was 1.6 times higher in NUCL and 2.6 times in VL patients compared to the control. Concerning the immunoglobulins subclass, only VL patients showed positive reaction for IgG1, and IgG2 did not show positive reaction among the groups. The results showed a weak cellular and humoral systemic immune response in NUCL patients.
- Comparative Genomic Analyses of New and Old World Viscerotropic Leishmanine Parasites: Further Insights into the Origins of Visceral Leishmaniasis Agents(2023) SILVEIRA, Fernando Tobias; SOUSA, Edivaldo Costa; SILVESTRE, Rodrigo Vellasco Duarte; SANTOS, Thiago Vasconcelos dos; SOSA-OCHOA, Wilfredo; VALERIANO, Concepcion Zuniga; RAMOS, Patricia Karla Santos; CASSEB, Samir Mansour Moraes; LIMA, Luciana Vieira do Rego; CAMPOS, Marliane Batista; MATTA, Vania Lucia da; GOMES, Claudia Maria; FLORES, Gabriela V. Araujo; PACHECO, Carmen M. Sandoval M.; CORBETT, Carlos Eduardo; LAURENTI, Marcia DalastraVisceral leishmaniasis (VL), also known as kala-azar, is an anthropozoonotic disease affecting human populations on five continents. Aetiologic agents belong to the Leishmania (L.) donovani complex. Until the 1990s, three leishmanine parasites comprised this complex: L. (L.) donovani Laveran & Mesnil 1903, L. (L.) infantum Nicolle 1908, and L. (L.) chagasi Lainson & Shaw 1987 (=L. chagasi Cunha & Chagas 1937). The VL causal agent in the New World (NW) was previously identified as L. (L.) chagasi. After the development of molecular characterization, however, comparisons between L. (L.) chagasi and L. (L.) infantum showed high similarity, and L. (L.) chagasi was then regarded as synonymous with L. (L.) infantum. It was, therefore, suggested that L. (L.) chagasi was not native to the NW but had been introduced from the Old World by Iberian colonizers. However, in light of ecological evidence from the NW parasite's enzootic cycle involving a wild phlebotomine vector (Lutzomyia longipalpis) and a wild mammal reservoir (the fox, Cerdocyon thous), we have recently analyzed by molecular clock comparisons of the DNA polymerase alpha subunit gene the whole-genome sequence of L. (L.) infantum chagasi of the most prevalent clinical form, atypical dermal leishmaniasis (ADL), from Honduras (Central America) with that of the same parasite from Brazil (South America), as well as those of L. (L.) donovani (India) and L. (L.) infantum (Europe), which revealed that the Honduran parasite is older ancestry (382,800 ya) than the parasite from Brazil (143,300 ya), L. (L.) donovani (33,776 ya), or L. (L.) infantum (13,000 ya). In the present work, we have now amplified the genomic comparisons among these leishmanine parasites, exploring mainly the variations in the genome for each chromosome, and the number of genomic SNPs for each chromosome. Although the results of this new analysis have confirmed a high genomic similarity (similar to 99%) among these parasites [except L. (L.) donovani], the Honduran parasite revealed a single structural variation on chromosome 17, and the highest frequency of genomic SNPs (more than twice the number seen in the Brazilian one), which together to its extraordinary ancestry (382,800 ya) represent strong evidence that L. (L.) chagasi/L. (L.) infantum chagasi is, in fact, native to the NW, and therefore with valid taxonomic status. Furthermore, the Honduran parasite, the most ancestral viscerotropic leishmanine parasite, showed genomic and clinical taxonomic characteristics compatible with a new Leishmania species causing ADL in Central America.
- In situ cellular immune response in non-ulcerated skin lesions due to Leishmania (L.) infantum chagasi infection(2021) SANDOVAL, Carmen; ARAUJO, Gabriela; SOSA, Wilfredo; AVALOS, Sara; SILVEIRA, Fernando; CORBETT, Carlos; ZUNIGA, Concepcion; LAURENTI, MarciaBackground: Skin lesions of patients affected by non-ulcerated cutaneous leishmaniasis (NUCL) caused by L. (L.) infantum chagasi are characterized by lymphohistiocytic inflammatory infiltrate associated with epithelioid granuloma and scarce parasitism. However, the in situ cellular immune response of these patients is unclear. Therefore, the aim of the present study was to characterize the cellular immune response in the skin lesions of patients affected by NUCL. Methods: Twenty biopsies were processed by immunohistochemistry using primary antibodies to T lymphocytes (CD4, CD8), NK cells, B lymphocytes, macrophages, nitric oxide synthase and interferon-gamma. Results: Immunohistochemistry revealed higher expression of all cellular types and molecules (IFN-gamma, iNOS) in the dermis of diseased skin compared to the skin of healthy individuals (p < 0.05). Morphometric analysis performed in the skin lesions sections showed the predominance of CD8(+) T lymphocytes in the mononuclear infiltrate, followed by macrophages, mostly iNOS(+), a response that could be mediated by IFN-gamma. Conclusion: Our study improves knowledge of the cellular immune response in nonulcerated or atypical cutaneous leishmaniasis caused by L. (L.) infantum chagasi in Central America and pointed to the pivotal participation of CD8(+) T lymphocytes in the host defense mechanisms against the parasite in patients with NUCL.
- Role of antigen-presenting cells in non-ulcerated skin lesions caused by Leishmania (Leishmania) infantum chagasi(2023) PACHECO, Carmen M. Sandoval M.; FLORES, Gabriela V. Araujo V.; FERREIRA, Aurea F. F.; MATTA, Vania L. R. da; GOMES, Claudia M. de Castro M.; SOSA-OCHOA, Wilfredo H. H.; ZUNIGA, Concepcion; SILVEIRA, Fernando T. T.; CORBETT, Carlos E. P.; LAURENTI, Marcia D.In Central America, infection by Leishmania (Leishmania) infantum chagasi causes visceral leishmaniasis and non-ulcerated cutaneous leishmaniasis (NUCL). This work aimed to evaluate the participation of subpopulations of antigen-presenting cells in skin lesions of patients affected by NUCL through double-staining immunohistochemistry using cellular and intracellular markers. Twenty-three skin biopsies from patients affected by NUCL were used. Histological sections stained by HE were used for histopathological study. Immunohistochemical studies were performed using primary antibodies against Langerhans cells, dermal dendritic cells, T lymphocytes, and the cytokines IL-12, IFN-gamma, TNF-alpha, iNOS, and IL-10. The histopathological lesions were characterized by an inflammatory infiltrate, predominantly lymphohistiocytic, of variable intensity, with a diffuse arrangement associated with epithelioid granulomas and discreet parasitism. Double-staining immunohistochemistry showed higher participation of dendritic cells producing the proinflammatory cytokine IL-12 in relation to the other evaluated cytokines. Activation of the cellular immune response was marked by a higher density of CD8 Tc1-lymphocytes followed by CD4 Th1-lymphocytes producing mainly IFN-gamma. The data obtained in the present study suggest that antigen-presenting cells play an important role in the in situ immune response through the production of proinflammatory cytokines, directing the cellular immune response preferentially to the Th1 and Tc1 types in NUCL caused by L. (L.) infantum chagasi.