Murine experimental leprosy: Evaluation of immune response by analysis of peritoneal lavage cells and footpad histopathology.

This study evaluated the immune response of nude and BALB/c mice inoculated in the footpads (FP) with Mycobacterium leprae after 3, 5 and 8 months. At each timepoint peritoneal cells, peripheral blood, FP and popliteal lymph nodes (PLN) were collected. Peritoneal cell cultures were performed to measure the H2 O2 , O2- , NO, IL-2, IL-4, IL-10, IL-12, IFN-γ and TNF levels. Serum levels of anti-PGL-I antibodies were also quantified. The results showed that the infection was progressive in nude mice with bacterial multiplication, development of macroscopic lesions in the FP and presence of bacilli in the PLN at 8 months. In BALB/c mice, the infection reached a plateau of bacillary multiplication at 5 months and regressed at 8 months. Histopathological analysis of FP revealed a mononuclear inflammatory infiltrate with a large number of neutrophils at 5 months, with a higher number in nude mice. At 8 months, the number of neutrophils decreased and the infiltrate was predominantly mononuclear in both mouse strains. There was no H2 O2, O2- , IL-2, IL-4, IL-10 and IFN-γ production in the course of infection in nude mice; however, in BALB/c, O2- and IL-12 production was higher at 5 months and NO, IFN-γ and TNF production was higher at 8 months when there was a decrease in the number of bacilli. The level of anti-PGL-I antibodies was higher in BALB/c mice. Thus, nude and BALB/c mice can be used as experimental models for the study of various aspects of leprosy.

Nutritional status and immune response in murine experimental Jorge Lobo's disease.

There are no studies investigating the role of nutritional status and immunity associated with Jorge Lobo's disease. The objective of this study was to evaluate the effects of protein-calorie malnutrition on the immune response of BALB/c mice inoculated with Lacazia loboi. In this study,the animals were divided into four groups: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. The animals of groups G1 and G2 were submitted to malnutrition for 20 days and once installed the animals were inoculated intradermally into the footpad. After 4 months, they were euthanised for the isolation of peritoneal lavage cells and removal of the footpad. The production of IL-2, IL-4, IL-10, IL-12, IFN-γ, TNF-α, H2 O2 and nitric oxide (NO) was evaluated in the peritoneal lavage cells. The footpad was evaluated regarding the size of macroscopic lesions, number of fungi and viability index. The results showed that the infection did not exert great influence on the body weight of the mice and previous malnutrition was an unfavourable factor for viability index, number of fungi, macroscopic lesion size in the footpad and production of H2 O2 , NO, IL-12, IL-10 and IFN-γ, suggesting that malnutrition significantly altered fungal activity and peritoneal cells. The results suggest considerable interaction between nutrition and immunity in Jorge Lobo's disease.

THE RELEVANCE OF NUTRITIONAL STATUS AND HISTOPATHOLOGICAL FINDINGS ON THE INFECTIOUS PROCESS OF BALB/C MICE INOCULATED WITH Lacazia loboi.

The aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.

Search for Mycobacterium leprae in wild mammals.

Leprosy is still a worldwide public health problem. Brazil and India show the highest prevalence rates of the disease. Natural infection of armadillos Dasypus novemcinctus with Mycobacterium leprae has been reported in some regions of the United States. Identification of bacilli is difficult, particularly due to its inability to grow in vitro. The use of molecular tools represents a fast and sensitive alternative method for diagnosis of mycobacteriosis. In the present study, the diagnostic methods used were bacilloscopy, histopathology, microbiology, and PCR using specific primers for M. leprae repetitive sequences. PCR were performed using genomic DNA extracted from 138 samples of liver, spleen, lymph nodes, and skin of 44 D. novemcinctus, Euphractus sexcinctus, Cabassous unicinctus, and C. tatouay armadillos from the Middle Western region of the state of São Paulo and from the experimental station of Embrapa Pantanal, located in Pantanal da Nhecolândia of Mato Grosso do Sul state. Also, the molecular analysis of 19 samples from internal organs of other road killed species of wild animals, such as Nasua nasua (ring-tailed coati), Procyon cancrivoros (hand-skinned), Cerdocyon thous (dog-pity-bush), Cavia aperea (restless cavy), Didelphis albiventris (skunk), Sphigurrus spinosus (hedgehog), and Gallictis vittata (ferret) showed PCR negative data. None of the 157 analyzed samples had shown natural mycobacterial infection. Only the armadillo inoculated with material collected from untreated multibacillary leprosy patient presented PCR positive and its genomic sequencing revealed 100% identity with M. leprae. According to these preliminary studies, based on the used methodology, it is possible to conclude that wild mammals seem not to play an important role in the epidemiology of leprosy in the Middle Western region of the São Paulo state and in the Pantanal of Mato Grosso do Sul state.

THE RELEVANCE OF NUTRITIONAL STATUS AND HISTOPATHOLOGICAL FINDINGS ON THE INFECTIOUS PROCESS OF BALB/C MICE INOCULATED WITH Lacazia loboi / A relevância do estado nutricional e alterações histopatológicas no processo infeccioso de camundongos BALB/c inoculados com Lacazia loboi

SUMMARY The aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.

RESUMO O objetivo do estudo foi avaliar os efeitos da desnutrição protéico-calórica em camundongos isogênicos da linhagem BALB/c inoculados com Lacazia loboi, empregando parâmetros nutricionais e histopatológicos. Foram constituídos quatro grupos: G1- inoculados com restrição dietética; G2- não inoculados com restrição dietética; G3- inoculados sem restrição dietética; G4- não inoculados sem restrição dietética. Após instalada a desnutrição, os animais foram inoculados via intradérmica no coxim plantar e após quatro meses foram sacrificados para remoção do coxim plantar, fígado e baço. A infecção não exerceu grande influência no peso corporal dos camundongos. O peso do fígado e baço apresentou redução nos grupos desnutridos em comparação aos grupos nutridos. A lesão macroscópica, a viabilidade e o número total de fungos dos coxins plantares dos camundongos inoculados revelaram aumento no G3 quando comparado com o G1. Em relação à análise histopatológica dos coxins plantares observou-se aumento da celularidade global na composição do granuloma no G3 em relação ao G1, com grande número de macrófagos e células gigantes multinucleadas, discretos números de linfócitos estavam presentes em G3 e aumentados no G1. Os resultados sugerem que existe grande interação entre nutrição e doença de Jorge Lobo.