(Table 3) Liver weight, blood liver parameters, and blood plasma PCB concentrations in 14 sledge dog bitches and their 14 pups in Aasiaat, west Greenland

We assessed the relationship between exposure to organohalogen polluted minke whale (Balaenoptera acutorostrata) blubber and liver morphology and function in a generational controlled study of 28 Greenland sledge dogs (Canis familiaris). The prevalence of portal fibrosis, mild bile duct hyperplasia, and vascular leukocyte infiltrations was significantly higher in the exposed group (all Chi-square: p<0.05). In case of granulomas, the frequency was significantly highest in the bitches (P generation) while the prevalence of portal fibrosis was highest in the F generation (pups) (both Chi-square: p<0.05). No significant difference between exposed and controls was found for bile acid, ALAT, and ALKP, while ASAT and LDH were significantly highest in the control group (both ANOVA: p<0.05). We therefore suggest that a daily intake of 50-200 g environmentally organohalogen polluted minke whale blubber can cause liver lesions in Greenland sledge dogs. It is reasonable to infer that other apex predators such as polar bears (Ursus maritimus) and humans may suffer from similar impacts.

Severe reduction in leukocyte adhesion and monocyte extravasation in mice deficient in CC chemokine receptor 2

CC chemokine receptor 2 (CCR2) is a prominent receptor for the monocyte chemoattractant protein (MCP) group of CC chemokines. Mice generated by gene targeting to lack CCR2 exhibit normal leukocyte rolling but have a pronounced defect in MCP-1-induced leukocyte firm adhesion to microvascular endothelium and reduced leukocyte extravasation. Constitutive macrophage trafficking into the peritoneal cavity was not significantly different between CCR2-deficient and wild-type mice. However, after intraperitoneal thioglycollate injection, the number of peritoneal macrophages in CCR2-deficient mice did not rise above basal levels, whereas in wild-type mice the number of macrophages at 36 h was ≈3.5 times the basal level. The CCR2-deficient mice showed enhanced early accumulation and delayed clearance of neutrophils and eosinophils. However, by 5 days neutrophils and eosinophils in both CCR2-deficient and wild-type mice had returned to near basal levels, indicating that resolution of this inflammatory response can occur in the absence of macrophage influx and CCR2-mediated activation of the resident peritoneal macrophages. After intravenous injection with yeast β-glucan, wild-type mice formed numerous large, well-defined granulomas throughout the liver parenchyma, whereas CCR2-deficient mice had much fewer and smaller granulomas. These results demonstrate that CCR2 is a major regulator of induced macrophage trafficking in vivo.

Collagenase-3 Induction in Rat Lung Fibroblasts Requires the Combined Effects of Tumor Necrosis Factor-α and 12-Lipoxygenase Metabolites: A Model of Macrophage-induced, Fibroblast-driven Extracellular Matrix Remodeling during Inflammatory Lung Injury

The mechanisms responsible for the induction of matrix-degrading proteases during lung injury are ill defined. Macrophage-derived mediators are believed to play a role in regulating synthesis and turnover of extracellular matrix at sites of inflammation. We find a localized increase in the expression of the rat interstitial collagenase (MMP-13; collagenase-3) gene from fibroblastic cells directly adjacent to macrophages within silicotic rat lung granulomas. Conditioned medium from macrophages isolated from silicotic rat lungs was found to induce rat lung fibroblast interstitial collagenase gene expression. Conditioned medium from primary rat lung macrophages or J774 monocytic cells activated by particulates in vitro also induced interstitial collagenase gene expression. Tumor necrosis factor-α (TNF-α) alone did not induce interstitial collagenase expression in rat lung fibroblasts but did in rat skin fibroblasts, revealing tissue specificity in the regulation of this gene. The activity of the conditioned medium was found to be dependent on the combined effects of TNF-α and 12-lipoxygenase-derived arachidonic acid metabolites. The fibroblast response to this conditioned medium was dependent on de novo protein synthesis and involved the induction of nuclear activator protein-1 activity. These data reveal a novel requirement for macrophage-derived 12-lipoxygenase metabolites in lung fibroblast MMP induction and provide a mechanism for the induction of resident cell MMP gene expression during inflammatory lung processes.

Genetic control of resistance to experimental infection with virulent Mycobacterium tuberculosis

Over 2 billion people are estimated to be infected with virulent Mycobacterium tuberculosis, yet fewer than 10% progress to clinical tuberculosis within their lifetime. Twin studies and variations in the outcome of tuberculosis infection after exposure to similar environmental risks suggest genetic heterogeneity among individuals in their susceptibility to disease. In a mouse model of tuberculosis, we have established that resistance and susceptibility to virulent M. tuberculosis is a complex genetic trait. A new locus with a major effect on tuberculosis susceptibility, designated sst1 (susceptibility to tuberculosis 1), was mapped to a 9-centimorgan (cM) interval on mouse chromosome 1. It is located 10–19 cM distal to a previously identified gene, Nramp1, that controls the innate resistance of mice to the attenuated bacillus Calmette–Guérin vaccine strain. The phenotypic expression of the newly identified locus is distinct from that of Nramp1 in that sst1 controls progression of tuberculosis infection in a lung-specific manner. Mice segregating at the sst1 locus exhibit marked differences in the growth rates of virulent tubercle bacilli in the lungs. Lung lesions in congenic sst1-susceptible mice are characterized by extensive necrosis and unrestricted extracellular multiplication of virulent mycobacteria, whereas sst1-resistant mice develop interstitial granulomas and effectively control multiplication of the bacilli. The resistant allele of sst1, although powerful in controlling infection, is not sufficient to confer full protection against virulent M. tuberculosis, indicating that other genes located outside of the sst1 locus are likely also to be important for controlling tuberculosis infection.

A mAb recognizing a surface antigen of Mycobacterium tuberculosis enhances host survival

Murine mAbs reactive with the surface of Mycobacterium tuberculosis were assayed for their ability to affect the course of infection in mice challenged with virulent organisms. An IgG3 mAb (9d8) specific for arabinomannan and reactive with purified antigen from a clinical isolate of M. tuberculosis conferred partial protection on mice after respiratory challenge (30–60% survival >75 days; P ≤ 0.05). Control mice pretreated with an irrelevant mAb of the same isotype succumbed to tuberculosis within 30 days. Mice with gene disruptions in interferon γ and major histocompatibility complex Class II also were partially protected from challenge. The protective mAb was neither bactericidal nor inhibitory of infection or bacterial replication. Nevertheless, it profoundly altered the nature of the granulomas in the infected lungs. Mice treated with mAb 9d8 and challenged with M. tuberculosis localized the pathogen within granuloma centers, suggesting that the mAb conferred protection by enhancing a cellular immune response.

Defective localization of the NADPH phagocyte oxidase to Salmonella-containing phagosomes in tumor necrosis factor p55 receptor-deficient macrophages

Tumor necrosis factor receptor (TNFR) p55-knockout (KO) mice are susceptible profoundly to Salmonella infection. One day after peritoneal inoculation, TNFR-KO mice harbor 1,000-fold more bacteria in liver and spleen than wild-type mice despite the formation of well organized granulomas. Macrophages from TNFR-KO mice produce abundant quantities of reactive oxygen and nitrogen species in response to Salmonella but nevertheless exhibit poor bactericidal activity. Treatment with IFN-γ enhances killing by wild-type macrophages but does not restore the killing defect of TNFR-KO cells. Bactericidal activity of macrophages can be abrogated by a deletion in the gene encoding TNFα but not by saturating concentrations of TNF-soluble receptor, suggesting that intracellular TNFα can regulate killing of Salmonella by macrophages. Peritoneal macrophages from TNFR-KO mice fail to localize NADPH oxidase-containing vesicles to Salmonella-containing vacuoles. A TNFR-KO mutation substantially restores virulence to an attenuated mutant bacterial strain lacking the type III secretory system encoded by Salmonella pathogenicity island 2 (SPI2), suggesting that TNFα and SPI2 have opposing actions on a common pathway of vesicular trafficking. TNFα–TNFRp55 signaling plays a critical role in the immediate innate immune response to an intracellular pathogen by optimizing the delivery of toxic reactive oxygen species to the phagosome.

The human lysozyme promoter directs reporter gene expression to activated myelomonocytic cells in transgenic mice.

The 5' region of the human lysozyme gene from -3500 to +25 was fused to a chloramphenicol acetyltransferase (CAT) reporter gene and three transgenic founder mice were obtained. All three transgenic lines showed the same pattern of CAT enzyme expression in adult mouse tissues that was consistent with the targeting of elicited, activated macrophages in tissues and developing and elicited granulocytes. In normal mice high CAT enzyme activity was found in the spleen, lung, and thymus, tissues rich in phagocytically active cells, but not in many other tissues, such as the gut and muscle, which contain resident macrophages. Cultured resident peritoneal macrophages and cells elicited 18 hr (granulocytes) and 4 days (macrophages) after injection of sterile thioglycollate broth expressed CAT activity. Bacillus Calmette-Guérin infection of transgenic mice resulted in CAT enzyme expression in the liver, which contained macrophage-rich granulomas, whereas the liver of uninfected mice did not have any detectable CAT enzyme activity. Although the Paneth cells of the small intestine in both human and mouse produce lysozyme, the CAT gene, under the control of the human lysozyme promoter, was not expressed in the mouse small intestine. These results indicate that the human lysozyme promoter region may be used to direct expression of genes to activated mouse myeloid cells.

CLARITY and PACT-based imaging of adult zebrafish and mouse for whole-animal analysis of infections.

Visualization of infection and the associated host response has been challenging in adult vertebrates. Owing to their transparency, zebrafish larvae have been used to directly observe infection in vivo; however, such larvae have not yet developed a functional adaptive immune system. Cells involved in adaptive immunity mature later and have therefore been difficult to access optically in intact animals. Thus, the study of many aspects of vertebrate infection requires dissection of adult organs or ex vivo isolation of immune cells. Recently, CLARITY and PACT (passive clarity technique) methodologies have enabled clearing and direct visualization of dissected organs. Here, we show that these techniques can be applied to image host-pathogen interactions directly in whole animals. CLARITY and PACT-based clearing of whole adult zebrafish and Mycobacterium tuberculosis-infected mouse lungs enables imaging of mycobacterial granulomas deep within tissue to a depth of more than 1 mm. Using established transgenic lines, we were able to image normal and pathogenic structures and their surrounding host context at high resolution. We identified the three-dimensional organization of granuloma-associated angiogenesis, an important feature of mycobacterial infection, and characterized the induction of the cytokine tumor necrosis factor (TNF) within the granuloma using an established fluorescent reporter line. We observed heterogeneity in TNF induction within granuloma macrophages, consistent with an evolving view of the tuberculous granuloma as a non-uniform, heterogeneous structure. Broad application of this technique will enable new understanding of host-pathogen interactions in situ.

Transcriptional profiling of chronic clinical hepatic schistosomiasis japonica indicates reduced metabolism and immune responses

Schistosomiasis is a significant cause of human morbidity and mortality. We performed a genome-wide transcriptional survey of liver biopsies obtained from Chinese patients with chronic schistosomiasis only, or chronic schistosomiasis with a current or past history of viral hepatitis B. Both disease groups were compared with patients with no prior history or indicators of any liver disease. Analysis showed in the main, downregulation in gene expression, particularly those involved in signal transduction via EIF2 signalling and mTOR signalling, as were genes associated with cellular remodelling. Focusing on immune associated pathways, genes were generally downregulated. However, a set of three genes associated with granulocytes, MMP7, CLDN7, CXCL6 were upregulated. Differential gene profiles unique to schistosomiasis included the gene Granulin which was decreased despite being generally considered a marker for liver disease, and IGBP2 which is associated with increased liver size, and was the most upregulated gene in schistosomiasis only patients, all of which presented with hepatomegaly. The unique features of gene expression, in conjunction with previous reports in the murine model of the cellular composition of granulomas, granuloma formation and recovery, provide an increased understanding of the molecular immunopathology and general physiological processes underlying hepatic schistosomiasis.

Oral foreign body granuloma: unusual presentation of a rare adverse reaction to permanent injectable cosmetic filler

COSTA MIGUEL, M. C.; NONAKA, C. F. W.; GERMANO, A. R.; SOUZA, L. B.; SOUZA, L. B. Oral foreign body granuloma: unusual presentation of a rare adverse reaction to permanent injectable cosmetic filler. International journal of oral and maxillofacial surgery, v. 38, p. 385-387, 2009.

Oral foreign body granuloma: unusual presentation of a rare adverse reaction to permanent injectable cosmetic filler

COSTA MIGUEL, M. C.; NONAKA, C. F. W.; GERMANO, A. R.; SOUZA, L. B.; SOUZA, L. B. Oral foreign body granuloma: unusual presentation of a rare adverse reaction to permanent injectable cosmetic filler. International journal of oral and maxillofacial surgery, v. 38, p. 385-387, 2009.

Bartonelosis sistémica con lesiones hepatoesplénicas en un paciente inmunocompetente: Presentación de un caso y revisión de la bibliografía

Resumen La enfermedad por arañazo de gato (EAG) es una enfermedad infecciosa causada por Bartonella henselae. Esta enfermedad es de evolución habitualmente benigna, el beneficio del tratamiento antibiótico no está claramente demostrado, sin embargo algunos pacientes desarrollan formas atípicas y más graves con compromiso sistémico como la formación de granulomas hepáticos y esplénicos. Se presenta el caso clínico de una niña de 10 años con granulomas hepáticos que fue asistida en el Centro Hospitalario Pereira Rossell por fiebre prolongada, astenia, dolor abdominal y adelgazamiento. Lo que obliga a investigar la etiología y descartar diagnósticos diferenciales y proponer alternativas terapéuticas. En ese momento no disponíamos de estudios serológicos para la búsqueda etiológica en el país lo cual generó dificultades diagnósticas en esta paciente. Finalmente se pudo obtener la confirmación serológica de EAG de la paciente al enviar la muestra al Hospital de Niños Ricardo Gutiérrez en Buenos Aires prácticamente un mes después de iniciado los síntomas. Fue tratada inicialmente con azitromicina vía oral 10 mg/kg/día por 10 días y dada la tórpida evolución se utiliza un segundo plan antibiótico que incluyó claritromicina 15 mg/kg/día más rifampicina 20 mg/kg/día por 6 semanas. La paciente evolucionó favorablemente, presentando disminución progresiva del tamaño de los granulomas hepáticos y esplénicos. Discusión: Los granulomas hepatoesplénicos constituyen una forma de presentación poco frecuente pero orientadora de la EAG. La evidencia en relación a su tratamiento es escasa y deriva de series de casos. Es posible que los pacientes con manifestaciones sistémicas requieran tratamientos combinados y prolongados.

A Rare Manifestation of Crohn's Disease: Sinonasal Granulomatosis. Report of a Case and Review of Literature

Crohn’s disease is a granulomatous inflammatory bowel disease. Its pathologic findings include non-contiguous chronic inflammation and non-caseating granulomas, sometimes with extra-intestinal localizations. Sinonasal manifestations of Crohn’s disease are quite rare and only a few cases have been reported up to date in the worldwide literature. They are characterized by chronic mucosal inflammation, obstruction, bleeding and occasionally septal perforation. We report a case of sinonasal granulomatosis revealing Crohn’s disease in a 22-year-old woman and go over the available literature on sinonasal involvement in Crohn’s disease.

Gestation and breastfeeding in schistosomotic mothers differently modulate the immune response of adult offspring to postnatal Schistosoma mansoni infection

Schistosoma mansoni antigens in the early life alter homologous and heterologous immunity during postnatal infections. We evaluate the immunity to parasite antigens and ovalbumin (OA) in adult mice born/suckled by schistosomotic mothers. Newborns were divided into: born (BIM), suckled (SIM) or born/suckled (BSIM) in schistosomotic mothers, and animals from noninfected mothers (control). When adults, the mice were infected and compared the hepatic granuloma size and cellularity. Some animals were OA + adjuvant immunised. We evaluated hypersensitivity reactions (HR), antibodies levels (IgG1/IgG2a) anti-soluble egg antigen and anti-soluble worm antigen preparation, and anti-OA, cytokine production, and CD4+FoxP3+T-cells by splenocytes. Compared to control group, BIM mice showed a greater quantity of granulomas and collagen deposition, whereas SIM and BSIM presented smaller granulomas. BSIM group exhibited the lowest levels of anti-parasite antibodies. For anti-OA immunity, immediate HR was suppressed in all groups, with greater intensity in SIM mice accompanied of the remarkable level of basal CD4+FoxP3+T-cells. BIM and SIM groups produced less interleukin (IL)-4 and interferon (IFN)-g. In BSIM, there was higher production of IL-10 and IFN-γ, but lower levels of IL-4 and CD4+FoxP3+T-cells. Thus, pregnancy in schistosomotic mothers intensified hepatic fibrosis, whereas breastfeeding diminished granulomas in descendants. Separately, pregnancy and breastfeeding could suppress heterologous immunity; however, when combined, the responses could be partially restored in infected descendants.

Multi-Etiological Nature of Tuberculosis-Like Lesions in Condemned Pigs at the Slaughterhouse.

Tuberculosis-like lesions (TBL) in pigs have been associated with microorganisms other than mycobacteria. In this work a histopathological and microbiological evaluation of TBL in pigs is shown. A total of 352 samples belonging to 171 pigs totally condemned at slaughterhouse due to generalized TBL were sampled and selected for analysis. Pyogranulomatous (56.2%) and granulomatous lesions (20.2%) were observed in all analysed organs. Most of the granulomas observed in both lymph nodes and lungs belonged to more advanced stages of development (stages III and IV) whereas in the liver and the spleen most of lesions belonged to intermediate stages (stages II and III). Different microorganisms were simultaneously detected from TBL in the 42.7% of the animals. Mycobacterium tuberculosis complex (MTC) (38%), coryneform bacteria (40.3%) and streptococci (28.1%) were the main groups of microorganisms detected after bacteriological analysis, with Trueperella pyogenes and Streptococcus suis as the most frequently isolated species. Mycobacteria belonging to MTC were the most frequently detected pathogens in granulomatous and pyogranulomatous lesions in submandibular lymph nodes (32.7%) and coryneform bacteria were the microorganisms more frequently isolated from lungs (25.9%) and spleen samples (37.2%). These results may provide new insights into the pathogenesis and diagnosis of this pathology. The importance of coryneform bacteria and streptococci in such processes must be evaluated in future studies.