Lepromatous Lesions Research Articles

Exhausted CD8 T cells and anti-inflammatory macrophages characterize lepromatous leprosy lesions

Exhausted CD8 T cells and anti-inflammatory macrophages characterize lepromatous leprosy lesions

Potassium-Incorporated Titanium Oxide Nanoparticles Modulate Human Dendritic Cell Immune Response to Mycobacterium leprae

The two polar clinical forms of leprosy, termed tuberculoid and lepromatous, have polarized cellular immune responses with complex immunological distinctions. The predominance of DCs in tuberculoid leprosy has been reported, while the lepromatous pattern of illness is associated with weak activation of local populations of DCs. TiO2 nanoparticles have previously been shown to induce maturation of these cells, leading to an inflammatory response similar to adjuvant usage in vaccine administration. We aimed to evaluate the effect of potassium-incorporated Ti oxide nanostructures, namely KTiOxs, in the response of human monocyte-derived DCs to live M. leprae. Human monocytic cell line dual THP-1, which harbors two inducible reporter plasmid systems for transcription factor activation of NF-κB and interferon regulating factor (IRF), was treated with titanium control or with 1 mol/L KOH-treated Ti or 10 mol/L KOH for 24 h. Subsequently, cells were infected with M. leprae. KTiOx nanoparticles increase DC phagocytic activity without inflammation. KTiOx exposure of DCs led to an increase in IRF activation with modulation of the inflammatory response to live M. leprae. It also led to differential secretion of the critical components of innate immune response and the development of cell-mediated immunity against intracellular pathogens. This study demonstrates the effect of nanostructures of KTiOxs and the usefulness of nanoparticle technology in the in vitro activation of human DCs against an infectious disease with a puzzling immune spectrum. Our findings may prompt future therapeutic strategies, such as DC immunotherapy for disseminated and progressive lepromatous lesions.

Large-Scale Gene Expression Signatures Reveal a Microbicidal Pattern of Activation in Mycobacterium leprae-Infected Monocyte-Derived Macrophages With Low Multiplicity of Infection.

Leprosy is a disease with a clinical spectrum of presentations that is also manifested in diverse histological features. At one pole, lepromatous lesions (L-pole) have phagocytic foamy macrophages heavily parasitized with freely multiplying intracellular Mycobacterium leprae. At the other pole, the presence of epithelioid giant cells and granulomatous formation in tuberculoid lesions (T-pole) lead to the control of M. leprae replication and the containment of its spread. The mechanism that triggers this polarization is unknown, but macrophages are central in this process. Over the past few years, leprosy has been studied using large scale techniques to shed light on the basic pathways that, upon infection, rewire the host cellular metabolism and gene expression. M. leprae is particularly peculiar as it invades Schwann cells in the nerves, reprogramming their gene expression leading to a stem-like cell phenotype. This modulatory behavior exerted by M. leprae is also observed in skin macrophages. Here, we used live M. leprae to infect (10:1 multiplicity of infection) monocyte-derived macrophages (MDMs) for 48 h and analyzed the whole gene expression profile using microarrays. In this model, we observe an intense upregulation of genes consistent with a cellular immune response, with enriched pathways including peptide and protein secretion, leukocyte activation, inflammation, and cellular divalent inorganic cation homeostasis. Among the most differentially expressed genes (DEGs) are CCL5/RANTES and CYP27B1, and several members of the metallothionein and metalloproteinase families. This is consistent with a proinflammatory state that would resemble macrophage rewiring toward granulomatous formation observed at the T-pole. Furthermore, a comparison with a dataset retrieved from the Gene Expression Omnibus of M. leprae-infected Schwann cells (MOI 100:1) showed that the patterns among the DEGs are highly distinct, as the Schwann cells under these conditions had a scavenging and phagocytic gene profile similar to M2-like macrophages, with enriched pathways rearrangements in the cytoskeleton, lipid and cholesterol metabolism and upregulated genes including MVK, MSMO1, and LACC1/FAMIN. In summary, macrophages may have a central role in defining the paradigmatic cellular (T-pole) vs. humoral (L-pole) responses and it is likely that the multiplicity of infection and genetic polymorphisms in key genes are gearing this polarization.

Chronic Epididymo-Orchitis Mimicking Tuberculosis Turned Out to be Leprosy: A Case Report

We report a 55-year male with a prior history of treatment for bilateral Epididymo-orchitis without relief. We thought of genitourinary tuberculosis (GUTB) or nonspecific Epididymo-orchitis as differentials. Suddenly he developed crops of lepromatous skin lesions. On reviewing the literature, we found the involvement of testes in leprosy in 60-90% of cases. However, urology literature and textbooks do not mention leprosy to be a differential diagnosis of orchitis or chronic Epididymo-orchitis. Therefore, testicular atrophy, infertility or chronic Epididymo-orchitis should make us consider the possibility of leprosy, considering the half of the global burden in India.

IFN-β and IL-10 induce mTOR phosphorylation and regulate IFN-γ-induced autophagy during mycobacterial infection

Abstract The ability of mycobacteria to block the antimicrobial activity through the IFN-β→IL-10 pathway is critical to suppress IFN-γ induced antimicrobial response and increase mycobacterial survival. Leprosy is an infectious disease, caused by Mycobacterium leprae and IFN-γ is prevalent in the self-limited tuberculoid (T-lep) and reversal reaction (RR) lesions, whereas, IFN-β is higher in the disseminated lepromatous (L-lep) lesions. Here we investigated the role of the IFN-β→IL-10 pathway in the regulation of the IFN-γ-induced autophagy in M. leprae-infected macrophages. IFN-γ induced 65% more colocalization of the autophagosome with M. leprae compared to media alone. IFN-β and IL-10 reduced by 60% of the colocalization of LC3 and M. leprae induced by IFN-γ. The blocking of IL-10 recovered in 70% of the IFN-γ-induced autophagosomal fusion. Autophagy is negatively regulated by the mTOR complex 1 activation and live M. leprae induced phosphorylation of mTOR in 40% compared to uninfected MDMs. IFN-γ decreased the mTOR phosphorylation in 50% compared to media alone in M. leprae-infected MDMs. IL-10 reversed in 50% the IFN-γ-inhibition of mTOR phosphorylation in M. leprae infected macrophages. The colocalization of LC3 and M. leprae PGL-1 is higher in T-lep and RR in comparison with L-lep patients. However, mTOR phosphorylation was strongly detected in L-lep lesions vs. T-lep/RR lesions. The ability of the IFN-β → IL-10 pathway to inhibit IFN-γ-induced autophagy through induction of mTOR phosphorylation can be key for mycobacterial surveillance and inhibition of antigen presentation leading to disease pathogenesis.

Potential of AKR1B10 as a Biomarker and Therapeutic Target in Type 2 Leprosy Reaction.

The AKR1B10 (aldo-keto reductase family 1 member B10) gene has important functions in carcinogen-induced neoplasia. AKR1B10 is also expressed in type 2 reaction leprosy patients (R2). We measured the expression of AKR1B10 in the skin lesions of patients with leprosy by immunohistochemistry from biopsies that encompassed the spectrum of types of leprosy, based on the Ridley and Jopling classification [10 samples each of tuberculoid (TT), borderline tuberculoid (BT), mid-borderline (BB), and borderline lepromatous (BL) lesions; four samples of lepromatous lesions (LL)], reactional leprosy [14 samples of type 1 Reaction (R1) and 10 samples of type 2 Reaction (R2)], and biopsies from 9 healthy control (HC) subjects. In addition, 46 lepromatous lesions (BL and LL), 45 lepromatous lesions in regression, and 115 R2 lesions were included. Eight of 10 R2 samples (80%), 3 of 46 active BL and LL samples (6%), 23 of 45 BL and LL samples in regression (51%), and 107 of 115 R2 samples (93%) were positive for AKR1B10, differing significantly between all groups (p < 0.05). AKR1B10 expression was highest in the cytoplasm of macrophages. Thus, AKR1B10 is overexpressed on the lepromatous side (BL and LL) in samples that are in regression, especially type 2 reaction-associated lesions, rendering it a potential marker of type 2 reactional episodes of leprosy and a target of drugs against reactional episodes.

Sparfloxacin-induced photo-onycholysis and photosensitivity characteristically sparing lepromatous skin lesions: an interesting observation

Sparfloxacin is an antibiotic in the quinolone group of antibacterial agents, which often induce photosensitive skin reactions, more often phototoxic reactions than photoallergic ones, and sometimes associated photo-onycholysis. We present a case of phototoxic dermatitis with photo-onycholysis in a 38-year-old man probably induced by sparfloxacin, which was prescribed to him along with rifampicin and clofazimine because he was suffering from borderline lepromatous leprosy. He developed exaggerated sunburn-like eruptions mainly on sun-exposed sites along with painful onycholysis of the fingernails. Interestingly, the hypopigmented patches of leprosy were spared, which is a very rare phenomenon. Withdrawal of sparfloxacin along with administration of systemic steroids and other supportive measures helped heal the skin eruptions with hyperpigmentation, but the photo-onycholysis was slow to resolve.

Differential expression of solute carrier family 11a member 1 and inducible nitric oxide synthase 2 in skin biopsies from leprosy patients.

Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae, an intracellular parasite that resides within macrophages and cannot be eliminated effectively. Solute carrier family 11a member 1 (Slc11a1) and inducible nitric oxide synthase (iNOS), both expressed in macrophages, play major roles in host defense against several intracellular pathogens. However, the roles of these molecules in natural infection with M. leprae remain unknown. We aimed to investigate the expression of Slc11a1 and iNOS in macrophages (CD68+ cells) infiltrating skin lesions in leprosy. Skin biopsies from 48 Mexican patients of leprosy [(33 lepromatous (LL), 15 tuberculoid (TT)] and from 10 healthy controls, were subjected to immunohistochemistry to determine expression of CD68, Slc11a1 and iNOS. We found a high expression of Slc11a1 and iNOS in most lepromatous leprosy samples. In tuberculoid leprosy samples, Slc11a1 expression was moderate or low, and that of iNOS was almost always low. In addition, Slc11a1 and iNOS expression levels were positively associated with bacillary loads in lepromatous leprosy lesions (P=0.05). These observations suggest that M. leprae infection promotes the expression of Slc11a1 and iNOS in macrophages and that lepromatous leprosy can occur despite this response.

Differential dermal expression of CCL17 and CCL18 in tuberculoid and lepromatous leprosy.

BackgroundLeprosy is characterized by polar clinical, histologic and immunological presentations. Previous immunologic studies of leprosy polarity were limited by the repertoire of cytokines known at the time.MethodologyWe used a candidate gene approach to measure mRNA levels in skin biopsies from leprosy lesions. mRNA from 24 chemokines and cytokines, and 6 immune cell type markers were measured from 85 Nepalese leprosy subjects. Selected findings were confirmed with immunohistochemistry.Principal ResultsExpression of three soluble mediators (CCL18, CCL17 and IL-10) and one macrophage cell type marker (CD14) was significantly elevated in lepromatous (CCL18, IL-10 and CD14) or tuberculoid (CCL17) lesions. Higher CCL18 protein expression by immunohistochemistry and a trend in increased serum CCL18 in lepromatous lesions was observed. No cytokines were associated with erythema nodosum leprosum or Type I reversal reaction following multiple comparison correction. Hierarchical clustering suggested that CCL18 was correlated with cell markers CD209 and CD14, while neither CCL17 nor CCL18 were highly correlated with classical TH1 and TH2 cytokines.ConclusionsOur findings suggest that CCL17 and CCL18 dermal expression is associated with leprosy polarity.

Recidiva de lepra y reacción tipo II en paciente tratado con poliquimioterapia (PQT)

La lepra es una enfermedad infecciosa crónica propia de países de África, Asia, Oceanía y América Latina. Es causada por el Mycobacterium leprae que se manifiesta de forma variada como zonas de hipo o anestesia, máculas hipocrómicas, con o sin engrosamiento neural. En algunas ocasiones, después de haber completado el ciclo terapéutico recomendado por la Organización Mundial de la Salud, puede presentar recidivas, apareciendo nuevas lesiones clínicas o aumentando el índice bacilar. Esta características pueden confundirse con el eritema nodoso leproso, caracterizado por ser una reacción antígeno-anticuerpo que fija complemento mediante la cual el sistema inmune combate antígenos bacilares. En este texto se describe un caso de recidiva de lepra lepromatosa y lesiones compatibles con eritema nodoso leproso después de haber sido tratado con poliquimioterapia.

Type I interferon suppresses type II interferon-triggered human anti-mycobacterial responses.

Type I interferons (IFN-α and IFN-β) are important for protection against many viral infections, whereas type II interferon (IFN-γ) is essential for host defense against some bacterial and parasitic pathogens. Study of IFN responses in human leprosy revealed an inverse correlation between IFN-β and IFN-γ gene expression programs. IFN-γ and its downstream vitamin D-dependent antimicrobial genes were preferentially expressed in self-healing tuberculoid lesions and mediated antimicrobial activity against the pathogen Mycobacterium leprae in vitro. In contrast, IFN-β and its downstream genes, including interleukin-10 (IL-10), were induced in monocytes by M. leprae in vitro and preferentially expressed in disseminated and progressive lepromatous lesions. The IFN-γ-induced macrophage vitamin D-dependent antimicrobial peptide response was inhibited by IFN-β and by IL-10, suggesting that the differential production of IFNs contributes to protection versus pathogenesis in some human bacterial infections.

À propos d’une note de 1926 sur un essai du BCG dans le traitement de la lèpre

By 1926, two French physicians working in Indochina, R. Pons and L. Chastel, have suggested to treat leprosy by subcutaneous injections of bacillus Calmette-Guerin. This treatment appeared efficient since the lepromatous lesions quickly regressed and the Hansen bacillus disappeared from the nasal mucus. These results were quickly confirmed by other authors. They were all more appreciated than, at this time, the Chaulmoogra oil and its products, the only available drugs, were poorly efficient against the disease. Nevertheless, although not a panacea, the BCG therapy allowed to relieve these unfortunate patients until the beginning of the 1950's when an effective treatment by sulfones was at length available.

Increased hepcidin expression in multibacillary leprosy

Iron is essential for all organisms and its availability can control the growth of microorganisms; therefore, we examined the role of iron metabolism in multibacillary (MB) leprosy, focusing on the involvement of hepcidin. Erythrograms, iron metabolism parameters, pro-inflammatory cytokines and urinary hepcidin levels were evaluated in patients with MB and matched control subjects. Hepcidin expression in MB lesions was evaluated by quantitative polymerase chain reaction. The expression of ferroportin and hepcidin was evaluated by immunofluorescence in paucibacillary and MB lesions. Analysis of hepcidin protein levels in urine and of hepcidin mRNA and protein levels in leprosy lesions and skin biopsies from healthy control subjects showed elevated hepcidin levels in MB patients. Decreases in haematologic parameters and total iron binding capacity were observed in patients with MB leprosy. Moreover, interleukin-1 beta, ferritin, soluble transferrin receptor and soluble transferrin receptor/log ferritin index values were increased in leprosy patients. Hepcidin was elevated in lepromatous lesions, whereas ferroportin was more abundant in tuberculoid lesions. In addition, hepcidin and ferroportin were not colocalised in the biopsies from leprosy lesions. Anaemia was not commonly observed in patients with MB; however, the observed changes in haematologic parameters indicating altered iron metabolism appeared to result from a mixture of anaemia of inflammation and iron deficiency. Thus, iron sequestration inside host cells might play a role in leprosy by providing an optimal environment for the bacillus.

CD163 favors Mycobacterium leprae survival and persistence by promoting anti‐inflammatory pathways in lepromatous macrophages

Lepromatous macrophages possess a regulatory phenotype that contributes to the immunosuppression observed in leprosy. CD163, a scavenger receptor that recognizes hemoglobin-haptoglobin complexes, is expressed at higher levels in lepromatous cells, although its functional role in leprosy is not yet established. We herein demonstrate that human lepromatous lesions are microenvironments rich in IDO⁺CD163⁺. Cells isolated from these lesions were CD68⁺IDO⁺CD163⁺ while higher levels of sCD163 in lepromatous sera positively correlated with IL-10 levels and IDO activity. Different Myco-bacterium leprae (ML) concentrations in healthy monocytes likewise revealed a positive correlation between increased concentrations of the mycobacteria and IDO, CD209, and CD163 expression. The regulatory phenotype in ML-stimulated monocytes was accompanied by increased TNF, IL-10, and TGF-β levels whereas IL-10 blockade reduced ML-induced CD163 expression. The CD163 blockade reduced ML uptake in human monocytes. ML uptake was higher in HEK293 cells transfected with the cDNA for CD163 than in untransfected cells. Simultaneously, increased CD163 expression in lepromatous cells seemed to be dependent on ML uptake, and contributed to augmented iron storage in lepromatous macrophages. Altogether, these results suggest that ML-induced CD163 expression modulates the host cell phenotype to create a favorable environment for myco-bacterial entry and survival.

Immunohistochemical evaluation of macrophage activity and its relationship with apoptotic cell death in the polar forms of leprosy

The objective of the present study was to investigate the correlation between macrophage activity and apoptosis in the polar forms of leprosy because the immunopathological phenomena involved in these forms are still poorly understood. For this purpose, 29 skin biopsy samples obtained from patients with the polar forms of leprosy were analyzed. Macrophage activity and apoptosis were evaluated by immunohistochemistry using lysozyme, CD68, iNOS and caspase 3 as markers. The nonparametric Mann–Whitney test and Spearman’s linear correlation test were used for statistical analysis. The results suggest that the apoptosis rate is under the direct influence of macrophage activity in lesions of patients with the tuberculoid form. In contrast, in lepromatous lesions other factors seem to induce programmed cell death, possibly TGF-β. Further studies are necessary to identify additional factors involved in the immunopathogenesis of leprosy.

High Matrix Metalloproteinase Production Correlates with Immune Activation and Leukocyte Migration in Leprosy Reactional Lesions

Gelatinases A and B (matrix metalloproteinase 2 [MMP-2] and MMP-9, respectively) can induce basal membrane breakdown and leukocyte migration, but their role in leprosy skin inflammation remains unclear. In this study, we analyzed clinical specimens from leprosy patients taken from stable, untreated skin lesions and during reactional episodes (reversal reaction [RR] and erythema nodosum leprosum [ENL]). The participation of MMPs in disease was suggested by (i) increased MMP mRNA expression levels in skin biopsy specimens correlating with the expression of gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha), (ii) the detection of the MMP protein and enzymatic activity within the inflammatory infiltrate, (iii) increased MMP levels in patient sera, and (iv) the in vitro induction of MMP-9 by Mycobacterium leprae and/or TNF-alpha. It was observed that IFN-gamma, TNF-alpha, MMP-2, and MMP-9 mRNA levels were higher in tuberculoid than lepromatous lesions. In contrast, interleukin-10 and tissue inhibitor of MMP (TIMP-1) message were not differentially modulated. These data correlated with the detection of the MMP protein evidenced by immunohistochemistry and confocal microscopy. When RR and ENL lesions were analyzed, an increase in TNF-alpha, MMP-2, and MMP-9, but not TIMP-1, mRNA levels was observed together with stronger MMP activity (zymography/in situ zymography). Moreover, following in vitro stimulation of peripheral blood cells, M. leprae induced the expression of MMP-9 (mRNA and protein) in cultured cells. Overall, the present data demonstrate an enhanced MMP/TIMP-1 ratio in the inflammatory states of leprosy and point to potential mechanisms for tissue damage. These results pave the way toward the application of new therapeutic interventions for leprosy reactions.

Coordinate uptake of mycobacteria sand oxLDL by differential expression of IL‐10 and IL‐15 derived CD209+ macrophage subsets in human leprosy

Macrophage differentiation and function were investigated in the context of leprosy, which presents as a clinical and immunologic spectrum. The disseminated lepromatous (L‐lep) form is filled with lipid‐laden macrophages and numerous mycobacteria, while the localized tuberculoid form has macrophages but no mycobacteria found. Th1 macrophages correspond to T‐lep and can be derived in vitro with IL‐15. We hypothesized that the Th2 cytokine, IL‐10, can lead to CD209+ macrophage differentiation correlating to L‐lep macrophage phenotype and function. IL‐10 derived macrophages (M10) were found to express CD209 and CD163 in contrast to M15 being CD209+CD163−. M10 were determined to be highly endocytic by multiple assays and phagocytose more mycobacteria than IL‐15 derived macrophages (M15). Furthermore, M10 efficiently take in oxidized LDL (oxLDL) and become foam cell macrophages. Macrophage subsets in leprosy lesions were analyzed and we found CD209+CD163+ M10 macrophages in L‐lep lesions, while CD209+CD163− M15 macrophages were found in T‐Lep lesions. Furthermore, CD163+ macrophages in lepromatous leprosy lesions harbored mycobacteria and apolipoprotein B, a component of oxLDL, suggesting that M10 macrophage subset may lead to foam cell formation and mycobacterial uptake the pathogenesis of leprosy.

Relationships between clinical signs, pathological changes and tissue distribution of Mycobacterium avium subspecies paratuberculosis in 21 cows from herds affected by Johne's disease

Twenty-one cows from eight herds affected by Johne's disease were assigned to four groups: seven were not thriving and had persistent diarrhoea, six were not thriving and had intermittent diarrhoea,...

Molecular Characterization of a Novel Fastidious Mycobacterium Causing Lepromatous Lesions of the Skin, Subcutis, Cornea, and Conjunctiva of Cats Living in Victoria, Australia

Between 1999 and 2006, 15 cats were diagnosed with disease attributable to a novel mycobacterial species. The infections consisted of granulomatous lesions in the skin, subcutis, and ocular or periocular tissues with an indolent but progressive clinical course. Lesions typically were found in facial regions or on the distal limbs. Cats of all ages and both sexes were affected. Infections often were challenging to treat, although they could be cured using surgery in concert with combination antimicrobial therapy. Microscopically, lesions were granulomatous to pyogranulomatous and contained numerous acid-fast bacilli. Scanty cultures of the causal microorganisms occasionally could be obtained in mycobacterial broth, but subculture to solid media failed. When cultures were not available, DNA was extracted from fresh tissue, lyophilized material, and formalin-fixed, paraffin-embedded tissues from lesions. PCR amplification of the 5' end of the 16S rRNA gene and regions within four additional loci (ITS1, hsp65, rpoB, and sodA) was performed with various efficiencies using mycobacterial primers. Nucleotide sequences were unique for each locus tested. Nucleotide sequences obtained from individual cases were identical for each locus for which the amplification was successful. Phylogenetic analysis performed using concatenated partial 16S rRNA and hsp65 gene sequences indicated that this novel mycobacterial species from Victoria is a member of the Mycobacterium simiae-related group, taxonomically related to the mycobacterium causing leproid granulomas in dogs throughout the world. Based on the clustering of cases, we refer to this novel species as Mycobacterium sp. strain Tarwin.

Angiogenesis in Cutaneous Lesions of Leprosy

To examine the potential role of angiogenesis in leprosy. Immunohistochemical analysis of leprosy lesions. Department of Dermatology, Venereology, and Leprology, Kasturba Medical College; Division of Dermatology, University of California at Los Angeles; and Departments of Dermatology and Pathology, Emory University. Thirty-two cutaneous lesions that represented the spectrum of leprosy were obtained from 32 patients. CD31 microvessel counts. The mean CD31 microvessel count in borderline tuberculoid, midborderline, and lepromatous leprosy lesions was significantly higher than in indeterminate leprosy lesions. Increased bacterial load is associated with increased angiogenesis. Angiogenesis inhibitors may be of benefit in the treatment of leprosy.