Sensitivity and specificity of multibacillary and paucibacillary leprosy laboratory tests: A systematic review and meta-analysis.

This systematic review (number register: CRD42018112736) was performed to compare the sensitivity and specificity of leprosy diagnostic methods. The search was conducted in 3 electronic databases in January 2021. Studies evaluating leprosy diagnostic tests were included according the eligibility criteria. Meta-analysis was performed to calculate the sensibility and specificity of the groups. We included 36 studies. The test sensitivity for paucibacillary patients was 0.31 (95%CI: 0.29-0.33) and the specificity was 0.92 (95%CI: 0.92-0.93). In multibacillary patients, the sensitivity was 0.78 (95%CI: 0.77-0.80) and specificity was 0.92 (95%CI: 0.92-0.93). Comparing the sensitivity and specificity of the different techniques included, it should be noted that polymerase chain reaction (PCR) test presented the highest sensitivity for paucibacillary patients, while the western blot technique showed the highest sensitivity for multibacillary patients. However, further studies are needed to optimise the diagnosis of leprosy, requiring research with a larger number of samples and more uniform protocols.

Autophagy Is an Innate Mechanism Associated with Leprosy Polarization.

Leprosy is a chronic infectious disease that may present different clinical forms according to the immune response of the host. Levels of IFN-γ are significantly raised in paucibacillary tuberculoid (T-lep) when compared with multibacillary lepromatous (L-lep) patients. IFN-γ primes macrophages for inflammatory activation and induces the autophagy antimicrobial mechanism. The involvement of autophagy in the immune response against Mycobacterium leprae remains unexplored. Here, we demonstrated by different autophagic assays that LC3-positive autophagosomes were predominantly observed in T-lep when compared with L-lep lesions and skin-derived macrophages. Accumulation of the autophagic receptors SQSTM1/p62 and NBR1, expression of lysosomal antimicrobial peptides and colocalization analysis of autolysosomes revealed an impairment of the autophagic flux in L-lep cells, which was restored by IFN-γ or rapamycin treatment. Autophagy PCR array gene-expression analysis revealed a significantly upregulation of autophagy genes (BECN1, GPSM3, ATG14, APOL1, and TPR) in T-lep cells. Furthermore, an upregulation of autophagy genes (TPR, GFI1B and GNAI3) as well as LC3 levels was observed in cells of L-lep patients that developed type 1 reaction (T1R) episodes, an acute inflammatory condition associated with increased IFN-γ levels. Finally, we observed increased BCL2 expression in L-lep cells that could be responsible for the blockage of BECN1-mediated autophagy. In addition, in vitro studies demonstrated that dead, but not live M. leprae can induce autophagy in primary and lineage human monocytes, and that live mycobacteria can reduce the autophagy activation triggered by dead mycobacteria, suggesting that M. leprae may hamper the autophagic machinery as an immune escape mechanism. Together, these results indicate that autophagy is an important innate mechanism associated with the M. leprae control in skin macrophages.

IL-12 and IL-23 modulate plasticity of FoxP3+ regulatory T cells in human Leprosy.

Leprosy is a bacterial disease caused by M. leprae. Its clinical spectrum reflects the host's immune response to the M. leprae and provide an ideal model to investigate the host pathogen interaction and immunological dysregulation. Tregs are high in leprosy patients and responsible for immune suppression of the host by producing IL-10 and TGF-ß cytokines. In leprosy, plasticity of Tregs remain unstudied. This is the first study describing the conversion of Tregs into Th1-like and Th17-like cells using in vitro cytokine therapy in leprosy patients. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA), rIL-12 and rIL-23 for 48h. Expression of FoxP3 in CD4+CD25+ Tregs, intracellular cytokines IFN-γ, TGF-ß, IL-10 and IL-17 in Tregs cells were evaluated by flow cytometry (FACS) after stimulation. rIL-12 treatment increases the levels of pStat4 in Tregs and IFN-γ production. In the presence of rIL-23, pStat3+ and IL-17A+ cells increase. rIL-12 and r-IL-23 treatment downregulated the FoxP3 expression, IL-10 and TGF-ß production by Tregs and enhances the expression of co-stimulatory molecules (CD80, CD86). In conclusion rIL-12 converts Tregs into IFN-γ producing cells through STAT-4 signaling while rIL-23 converts Tregs into IL-17 producing cells through STAT-3 signaling in leprosy patients. This study may helpful to provide a new avenue to overcome the immunosuprression in leprosy patients using in vitro cytokine.

Autophagy is an innate mechanism associated with leprosy polarization

Leprosy is a chronic infectious disease that may present different clinical forms according to the immune response of the host. Levels of IFN-γ are significantly raised in paucibacillary tuberculoid (T-lep) when compared with multibacillary lepromatous (L-lep) patients. IFN-γ primes macrophages for inflammatory activation and induces the autophagy antimicrobial mechanism. The involvement of autophagy in the immune response against Mycobacterium leprae remains unexplored. Here, we demonstrated by different autophagic assays that LC3-positive autophagosomes were predominantly observed in T-lep when compared with L-lep lesions and skin-derived macrophages. Accumulation of the autophagic receptors SQSTM1/p62 and NBR1, expression of lysosomal antimicrobial peptides and colocalization analysis of autolysosomes revealed an impairment of the autophagic flux in L-lep cells, which was restored by IFN-γ or rapamycin treatment. Autophagy PCR array gene-expression analysis revealed a significantly upregulation of autophagy genes (BECN1, GPSM3, ATG14, APOL1, and TPR) in T-lep cells. Furthermore, an upregulation of autophagy genes (TPR, GFI1B and GNAI3) as well as LC3 levels was observed in cells of L-lep patients that developed type 1 reaction (T1R) episodes, an acute inflammatory condition associated with increased IFN-γ levels. Finally, we observed increased BCL2 expression in L-lep cells that could be responsible for the blockage of BECN1-mediated autophagy. In addition, in vitro studies demonstrated that dead, but not live M. leprae can induce autophagy in primary and lineage human monocytes, and that live mycobacteria can reduce the autophagy activation triggered by dead mycobacteria, suggesting that M. leprae may hamper the autophagic machinery as an immune escape mechanism. Together, these results indicate that autophagy is an important innate mechanism associated with the M. leprae control in skin macrophages.

Carbohydrate-dependent binding of langerin to SodC, a cell wall glycoprotein of Mycobacterium leprae.

Langerhans cells participate in the immune response in leprosy by their ability to activate T cells that recognize the pathogen, Mycobacterium leprae, in a langerin-dependent manner. We hypothesized that langerin, the distinguishing C-type lectin of Langerhans cells, would recognize the highly mannosylated structures in pathogenic Mycobacterium spp. The coding region for the extracellular and neck domain of human langerin was cloned and expressed to produce a recombinant active trimeric form of human langerin (r-langerin). Binding assays performed in microtiter plates, by two-dimensional (2D) Western blotting, and by surface plasmon resonance demonstrated that r-langerin possessed carbohydrate-dependent affinity to glycoproteins in the cell wall of M. leprae. This lectin, however, yielded less binding to mannose-capped lipoarabinomannan (ManLAM) and even lower levels of binding to phosphatidylinositol mannosides. However, the superoxide dismutase C (SodC) protein of the M. leprae cell wall was identified as a langerin-reactive ligand. Tandem mass spectrometry verified the glycosylation of a recombinant form of M. leprae SodC (rSodC) produced in Mycobacterium smegmatis. Analysis of r-langerin affinity by surface plasmon resonance revealed a carbohydrate-dependent affinity of rSodC (equilibrium dissociation constant [KD] = 0.862 µM) that was 20-fold greater than for M. leprae ManLAM (KD = 18.69 µM). These data strongly suggest that a subset of the presumptively mannosylated M. leprae glycoproteins act as ligands for langerin and may facilitate the interaction of M. leprae with Langerhans cells.

Mycobacterium leprae intracellular survival relies on cholesterol accumulation in infected macrophages: a potential target for new drugs for leprosy treatment.

We recently showed that Mycobacterium leprae (ML) is able to induce lipid droplet formation in infected macrophages. We herein confirm that cholesterol (Cho) is one of the host lipid molecules that accumulate in ML-infected macrophages and investigate the effects of ML on cellular Cho metabolism responsible for its accumulation. The expression levels of LDL receptors (LDL-R, CD36, SRA-1, SR-B1, and LRP-1) and enzymes involved in Cho biosynthesis were investigated by qRT-PCR and/or Western blot and shown to be higher in lepromatous leprosy (LL) tissues when compared to borderline tuberculoid (BT) lesions. Moreover, higher levels of the active form of the sterol regulatory element-binding protein (SREBP) transcriptional factors, key regulators of the biosynthesis and uptake of cellular Cho, were found in LL skin biopsies. Functional in vitro assays confirmed the higher capacity of ML-infected macrophages to synthesize Cho and sequester exogenous LDL-Cho. Notably, Cho colocalized to ML-containing phagosomes, and Cho metabolism impairment, through either de novo synthesis inhibition by statins or depletion of exogenous Cho, decreased intracellular bacterial survival. These findings highlight the importance of metabolic integration between the host and bacteria to leprosy pathophysiology, opening new avenues for novel therapeutic strategies to leprosy.

Diagnosis of American cutaneous leishmaniasis by enzyme immunoassay using membrane antigens of Leishmania (Viannia) braziliensis.

This study evaluated the reactivity of membrane antigens of Leishmania (Viannia) braziliensis for the diagnosis of ACL by enzyme immunoassay (EIA). Promastigotes of L. (V.) braziliensis were grown in medium 199 and lysed in a sonicator. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting showed that specific proteins of L. (V.) braziliensis (apparent molecular weights 36 kDa and 48-56 kDa) were recognized by sera from ACL patients. These proteins were eluted from the SDS-PAGE and tested in EIA-IgG with sera from ACL patients, healthy individuals, patients with toxoplasmosis, paracoccidioidomycosis, syphilis, tuberculosis, leprosy, and Chagas disease. The EIA-IgG with membrane antigens allowed us to distinguish patients with ACL from healthy individuals and patients with other diseases (P < 0.0001), and showed a sensitivity of 93.3% and specificity of 90.8%, not including Chagas disease patients. 2D-SDS-PAGE followed by Western blotting was performed to improve the characterization of the antigens, and showed a component with isoelectric points near the acid pH side and apparent molecular weights of 48-56 kDa. The results showed good sensitivity and specificity of EIA-IgG with membrane antigens, indicating their potential use for diagnosis of ACL, as well as seroepidemiological surveys and follow-up of clinically cured patients.

Mycobacterium leprae intracellular survival relies on cholesterol accumulation in infected macrophages: a potential target for new drugs for leprosy treatment

We recently showed that Mycobacterium leprae (ML) is able to induce lipid droplet formation in infected macrophages. We herein confirm that cholesterol (Cho) is one of the host lipid molecules that accumulate in ML-infected macrophages and investigate the effects of ML on cellular Cho metabolism responsible for its accumulation. The expression levels of LDL receptors (LDL-R, CD36, SRA-1, SR-B1, and LRP-1) and enzymes involved in Cho biosynthesis were investigated by qRT-PCR and/or Western blot and shown to be higher in lepromatous leprosy (LL) tissues when compared to borderline tuberculoid (BT) lesions. Moreover, higher levels of the active form of the sterol regulatory element-binding protein (SREBP) transcriptional factors, key regulators of the biosynthesis and uptake of cellular Cho, were found in LL skin biopsies. Functional in vitro assays confirmed the higher capacity of ML-infected macrophages to synthesize Cho and sequester exogenous LDL-Cho. Notably, Cho colocalized to ML-containing phagosomes, and Cho metabolism impairment, through either de novo synthesis inhibition by statins or depletion of exogenous Cho, decreased intracellular bacterial survival. These findings highlight the importance of metabolic integration between the host and bacteria to leprosy pathophysiology, opening new avenues for novel therapeutic strategies to leprosy.

Clofazimine modulates the expression of lipid metabolism proteins in Mycobacterium leprae-infected macrophages.

Mycobacterium leprae (M. leprae) lives and replicates within macrophages in a foamy, lipid-laden phagosome. The lipids provide essential nutrition for the mycobacteria, and M. leprae infection modulates expression of important host proteins related to lipid metabolism. Thus, M. leprae infection increases the expression of adipophilin/adipose differentiation-related protein (ADRP) and decreases hormone-sensitive lipase (HSL), facilitating the accumulation and maintenance of lipid-rich environments suitable for the intracellular survival of M. leprae. HSL levels are not detectable in skin smear specimens taken from leprosy patients, but re-appear shortly after multidrug therapy (MDT). This study examined the effect of MDT components on host lipid metabolism in vitro, and the outcome of rifampicin, dapsone and clofazimine treatment on ADRP and HSL expression in THP-1 cells. Clofazimine attenuated the mRNA and protein levels of ADRP in M. leprae-infected cells, while those of HSL were increased. Rifampicin and dapsone did not show any significant effects on ADRP and HSL expression levels. A transient increase of interferon (IFN)-ß and IFN-γ mRNA was also observed in cells infected with M. leprae and treated with clofazimine. Lipid droplets accumulated by M. leprae-infection were significantly decreased 48 h after clofazimine treatment. Such effects were not evident in cells without M. leprae infection. In clinical samples, ADRP expression was decreased and HSL expression was increased after treatment. These results suggest that clofazimine modulates lipid metabolism in M. leprae-infected macrophages by modulating the expression of ADRP and HSL. It also induces IFN production in M. leprae-infected cells. The resultant decrease in lipid accumulation, increase in lipolysis, and activation of innate immunity may be some of the key actions of clofazimine.

Desempenho de antígenos nativo, recombinante e sintético, em testes imunoenzimáticos, para diagnóstico e prognóstico de pacientes com diferentes formas clínicas de hanseníase / Performance of native, recombinant and synthetic antigens by enzyme immunoassays for the diagnosis and prognosis of leprosy patients classified in the wide spectrum of the disease

Apesar da Organização Mundial de Saúde (OMS) ter adotado medidas de controle, a hanseníase permanece como um problema social e de saúde pública em muitos países. O diagnóstico clínico e a baciloscopia permanecem como as principais ferramentas utilizadas para a classificação dos pacientes e definição da terapêutica a ser instituída. A identificação de novos antígenos de M. leprae, o desenvolvimento de novos métodos laboratoriais e melhorar o desempenho de testes sorológicos já existentes são prioridades para tentar atingir as metas da OMS programadas para o período de 2011-2015. Neste estudo avaliamos o desempenho diagnóstico dos antígenos glicolipídeo sintético ND-O-BSA para pesquisa de anticorpos totais e recombinante LID-1, para pesquisa anticorpos IgG por ELISA; e o perfil de reatividade de anticorpos IgG contra proteínas nativas de M. leprae por Western Blotting, em amostras de soros de pacientes de área endêmica com diferentes formas clínicas da doença. Nossos resultados mostraram que os testes ELISA ND-O-BSA e LID-1 auxiliaram na detecção de 70% dos pacientes multibacilares com baciloscopia negativa. O valor preditivo negativo foi de 94% para ambos os testes. A análise do Western Blotting mostrou que pacientes multibacilares possuem anticorpos IgG para a fração de 38kDa e região de 3,5kDa, esta reatividade não foi observada no grupo controle. Nosso estudo sugere a utilização do ELISA, com antígenos recombinante e sintético, na rotina diagnóstica; e que a fração de 38kDa e região de 3,5kDa, de antígeno nativo de M. leprae, são bons marcadores no diagnóstico de hanseníase e no prognóstico de pacientes com as formas borderline e indeterminada da doença

Although several control measures have been adopted by the World Health Organization, (WHO) leprosy continues to be a social and public health problem in many countries. Clinical diagnosis and acid-fast bacilli skin smear are the main tools used to classify patients and define therapy. According to the WHO program for 2011-2015, the identification of new Mycobacterium leprae antigens, the development of new laboratory methods and improved serological tests are the priorities. In the present study, we evaluated the diagnostic performance of the synthetic glycolipid antigen, ND-O-BSA, to detect total antibodies and the recombinant antigen LID-1 to detect IgG antibodies by ELISA and the IgG reactivity profile against native M. leprae proteins by Western blot in serum samples from leprosy patients classified in the wide spectrum of the disease. Our results showed that ND-O-BSA and LID-1 ELISA are able to detect the disease in 70% of multibacillary patients with negative skin smears. The negative predictive values were 94% for both tests. The Western blot analysis revealed that most multibacillary patients had IgG antibodies against the 38 kDa and 3.5 kDa regions; this reactivity was not observed in the control group. Our study suggests the use of ELISA, with recombinant or synthetic antigens, in routine diagnosis and that the 38 kDa fraction and the 3.5 kDa region, from native M leprae antigen, are good markers for the diagnosis of leprosy and its prognosis as shown for the borderline and indeterminate forms of the disease.

Apoptosis-inducing activity of clofazimine in macrophages.

Clofazimine is a riminophenazine compound which has been used for the treatment of leprosy since the 1960s. Although the drug is effective in the management of leprosy reactions because of its anti-inflammatory activity, the mechanism leading to the cessation of inflammation is not well understood. In the present study, it was shown that clofazimine exhibits apoptosis-inducing activity in macrophages. When human monocyte-derived macrophages were cultured in vitro in the presence of clofazimine, the cells exhibited a marked decrease in metabolic activity and showed shrinkage in cell size, indicating cell death. Nuclear condensation and fragmentation were also observed by Giemsa and Hoechst 33248 stains. The endonuclease inhibitor ZnCl(2) inhibited the clofazimine-induced cell death. Significant enhancement of caspase-3 activity was observed in clofazimine-treated macrophages and THP-1 cells. Collectively, these results suggest the apoptosis-inducing activity of clofazimine in macrophages, which may also be responsible for the antibacterial properties of clofazimine.

The role of indoleamine 2, 3-dioxygenase in lepromatous leprosy immunosuppression.

To elucidate further the possible role of the tryptophan, rate-limiting enzyme indoleamine 2, 3-dioxygenase (IDO) in leprosy, the distribution of IDO-positive cells and IDO activity in the skin biopsies and sera of these patients representing the entire spectrum of the disease were studied. An increased number of macrophages/dendritic cells (DC-lineage IDO(+) cells were found in lepromatous (LL) compared to tuberculoid (BT) and reversal reaction (RR) patients. IDO-positive cells showing CD68 and CD86 surface markers predominated in LL lesions, while higher levels of IDO activity were observed in the sera of LL versus BT patients. Tests revealed an increased IDO message in Mycobacterium leprae-stimulated peripheral blood mononuclear cells (PBMC) by real-time polymerase chain reaction (PCR) and increased IDO expression in M. leprae-stimulated CD14(+) cells of both healthy controls (HC) and LL patients, as evaluated via flow cytometry. Increased M. leprae-induced IDO-protein synthesis was also confirmed by Western blot. Based on our in vitro studies, it was confirmed that M. leprae up-regulated IDO expression and activity in HC and LL monocytes. Interferon (IFN)-γ synergized with M. leprae in promoting IDO expression and activity in monocytes. IDO expression induced by both IFN-γ and M. leprae was abrogated by 1-methyltryptophan (1-MT). Our data suggest that M. leprae chronic infection activates the suppressive molecule IDO which, in turn, contributes to the specific immunosuppression observed in LL leprosy.

Expression of Mycobacterium leprae HSP65 in tobacco and its effectiveness as an oral treatment in adjuvant-induced arthritis.

Transgenic plants are able to express molecules with antigenic properties. In recent years, this has led the pharmaceutical industry to use plants as alternative systems for the production of recombinant proteins. Plant-produced recombinant proteins can have important applications in therapeutics, such as in the treatment of rheumatoid arthritis (RA). In this study, the mycobacterial HSP65 protein expressed in tobacco plants was found to be effective as a treatment for adjuvant-induced arthritis (AIA). We cloned the hsp65 gene from Mycobacterium leprae into plasmid pCAMBIA 2301 under the control of the double 35S promoter from cauliflower mosaic virus. Agrobacterium tumefaciens bearing the pChsp65 plasmid was used to transform tobacco plants. Incorporation of the hsp65 gene was confirmed by PCR, reverse transcription-PCR, histochemistry, and western blot analyses in several transgenic lines of tobacco plants. Oral treatment of AIA rats with the HSP65 protein allowed them to recover body weight and joint inflammation was reduced. Our results suggest a synergistic effect between the HSP65 expressed protein and metabolites presents in tobacco plants.

Analysis of antibody responses to Mycobacterium leprae phenolic glycolipid I, lipoarabinomannan, and recombinant proteins to define disease subtype-specific antigenic profiles in leprosy.

A simple serodiagnostic test based on the Mycobacterium leprae-specific phenolic glycolipid I(PGL-I), for individuals with leprosy is nearly universally positive in leprosy patients with high bacillary loads but cannot be used as a stand-alone diagnostic test for the entire spectrum of the disease process. For patients with early infection with no detectable acid-fast bacilli in lesions or with low or no antibody titer to PGL-I, as in those at the tuberculoid end of the disease spectrum, this diagnostic approach has limited usefulness. To identify additional M. leprae antigens that might enhance the serological detection of these individuals, we have examined the reactivity patterns of patient sera to PGL-I, lipoarabinomannan (LAM), and six recombinant M. leprae proteins (ML1877, ML0841, ML2028, ML2038, ML0380, and ML0050) by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). Overall, the responses to ML2028 (Ag85B) and ML2038 (bacterioferritin) were consistently high in both multibacillary and paucibacillary groups and weak or absent in endemic controls, while responses to other antigens showed considerable variability, from strongly positive to completely negative. This analysis has given a clearer understanding of some of the differences in the antibody responses between individuals at opposite ends of the disease spectrum, as well as illustrating the heterogeneity of antibody responses toward protein, carbohydrate, and glycolipid antigens within a clinical group. Correlating these response patterns with a particular disease state could allow for a more critical assessment of the form of disease within the leprosy spectrum and could lead to better patient management.

Enhanced activation of T lymphocytes by urease-deficient recombinant bacillus Calmette-Guérin producing heat shock protein 70-major membrane protein-II fusion protein.

To activate naive T cells convincingly using Mycobacterium bovis bacillus Calmette-Guérin (BCG), recombinant BCG (BCG-D70M) that was deficient in urease, expressed with gene encoding the fusion of BCG-derived heat shock protein (HSP) 70 and Mycobacterium leprae-derived major membrane protein (MMP)-II, one of the immunodominant Ags of M. leprae, was newly constructed. BCG-D70M was more potent in activation of both CD4(+) and CD8(+) subsets of naive T cells than recombinant BCGs including urease-deficient BCG and BCG-70M secreting HSP70-MMP-II fusion protein. BCG-D70M efficiently activated dendritic cells (DCs) to induce cytokine production and phenotypic changes and activated CD4(+) T cells even when macrophages were used as APCs. The activation of both subsets of T cells was MHC and CD86 dependent. Pretreatment of DCs with chloroquine inhibited both surface expression of MMP-II on DCs and the activation of T cells by BCG-D70M-infected APCs. The naive CD8(+) T cell activation was inhibited by treatment of DCs with brefeldin A and lactacystin so that the T cell was activated by TAP- and proteosome-dependent cytosolic cross-priming pathway. From naive CD8(+) T cells, effector T cells producing perforin and memory T cells having migration markers were produced by BCG-D70M stimulation. BCG-D70M primary infection in C57BL/6 mice produced T cells responsive to in vitro secondary stimulation with MMP-II and HSP70 and more efficiently inhibited the multiplication of subsequently challenged M. leprae than vector control BCG. These results indicate that the triple combination of HSP70, MMP-II, and urease depletion may provide a useful tool for inducing better activation of naive T cells.

Colonization by Helicobacter pylori of leprosy patients in Spain: immunomodulation to low molecular weight antigens of H. pylori.

We studied the prevalence of Helicobacter pylori in patients with leprosy and the effects of co-infection on the immune response to Helicobacter antigens in the polar groups of leprosy (lepromatous and tuberculoid). We showed that there is no difference in the prevalence of H. pylori in patients with leprosy as compared to a non-leprosy population. We also demonstrated that the immune response to low molecular weight H. pylori antigens (35, 26 and 19 kDa) differs in patients with lepromatous as compared to those with tuberculoid leprosy. In lepromatous leprosy, we show that there is a higher prevalence of the 35 and 26 kDa antigens, but a lower prevalence of the 19 kDa antigen. These immunological results are consistent with previous histopathological studies illustrating a more severe gastrointestinal inflammation in lepromatous patients; importantly, a response to the 35 kDa antigen is recognized as a marker for the development of ulcerative disease.

Colonization by Helicobacter pylori of leprosy patients in Spain: immunomodulation to low molecular weight antigens of H. pylori

We studied the prevalence of Helicobacter pylori in patients with leprosy and the effects of co-infection on the immune response to Helicobacter antigens in the polar groups of leprosy (lepromatous and tuberculoid). We showed that there is no difference in the prevalence of H. pylori in patients with leprosy as compared to a non-leprosy population. We also demonstrated that the immune response to low molecular weight H. pylori antigens (35, 26 and 19 kDa) differs in patients with lepromatous as compared to those with tuberculoid leprosy. In lepromatous leprosy, we show that there is a higher prevalence of the 35 and 26 kDa antigens, but a lower prevalence of the 19 kDa antigen. These immunological results are consistent with previous histopathological studies illustrating a more severe gastrointestinal inflammation in lepromatous patients; importantly, a response to the 35 kDa antigen is recognized as a marker for the development of ulcerative disease.

Comparison of enzyme-linked immunosorbent assay test with immunoblot assay in the diagnosis of pemphigus in Indian patients.

BACKGROUND: The diagnosis of pemphigus vulgaris (PV) and pemphigus foliaceous (PF) rests upon clinical, histological and immunofluorescence features. Enzyme-linked immunosorbent assay (ELISA) test and immunoblot (IB) assay have shown variable sensitivity and specificity. AIMS: We compared the utility of ELISA and IB in pemphigus patients. METHODS: Sixty-six pemphigus cases (PV-54, PF-12) and 72 controls (other vesicobullous disorders and healthy controls) were inducted. ELISA for anti-Dsg 3 and 1 antibodies and IB assay were performed. RESULTS: On ELISA, both mean anti-Dsg 1 and 3 titers were raised in PV and PF. Mean anti-Dsg 1 in mucocutaneous PV was significantly higher than in mucosal PV and mean anti-Dsg 3 was significantly raised in PV than in PF. Anti-Dsg 1 and 3 in the control group were negative. Sensitivity and specificity of ELISA in PV was 98.14% and 90.5% while in PF it was 91.6% and 61.1%, respectively.On IB in PV, 36 cases (66.67%) showed the 130 kDa and 160 kDa antigen bands, 12 (22.2%) only the 130 kDa and six (11.1%) only the 160 kDa band. Eight of the nine pure mucosal cases (88.8%) showed only the 130 kDa. In PF, only the 160 kDa antigen was detected. These antigens were not identified in the control group. Sensitivity and specificity of IB in PV was 88.9% and 100% and in PF it was 100% and 95.2%, respectively. CONCLUSION: Both tests could differentiate pemphigus from other dermatoses, including other blistering disorders. ELISA could not make a distinction between PV and PF or between the various clinical phenotypes of PV. IB differentiated between PV and PF and the different clinical variants of PV.

Hypophosphorylation of NF-H and NF-M subunits of neurofilaments and the associated decrease in KSPXK kinase activity in the sciatic nerves of swiss white mice inoculated in the foot pad with mycobacterium leprae.

OBJECTIVE: To study the phosphorylation state of neurofilament (NF) proteins and activity of KSPXK kinase in the sciatic nerves of Swiss white (S/W) mice inoculated in the hind foot pads with M. leprae. DESIGN: Test group includes S/W mice inoculated in the foot pads with freshly harvested human derived (viable) M. leprae. Control groups were constituted by (1) Age matched un-inoculated mice, (2) Mice similarly inoculated with M. smegmatis and (3) heat killed M. leprae. Phosphorylation state of NF was studied using Western blot analysis and phosphor-specific NF antibody (SMI 31; Sternberger Monoclonals, Inc.). The KSPXK kinase activity was assayed by using KSPXK fusion protein in a radiometric method using gamma(22)P ATP. RESULTS: Several fold increase in M. leprae numbers was seen in viable M. leprae group while M. smegmatis failed to show any fold increase in the foot pads of S/W mice. Western immunoblot analysis of cytoskeletal preparation from sciatic nerves of uninoculated mice and mice inoculated with M. smegmatis showed immunoreactivity to SMI 31 antibody and protein bands corresponding to both NF-H and NF-M at all the time points from 4-20 months post inoculation. In case of viable M. leprae; SMI 31 reactive protein bands were seen at 4 months but not at any of the later intervals, i.e., between 6-20 months. With heat killed M. leprae transient loss of immunoreactivity to SMI 31 was seen. Decrease in KSPXK kinase activity was recorded in sets inoculated with viable and heat killed M. leprae, and corroborated with loss of immunoreactivity seen in WBs reacted with SMI 31 antibody. CONCLUSIONS: Alterations in the sciatic nerve NF cytoskeleton was seen following inoculation in the hind foot pad with both viable and heat killed M. leprae. The hypophosphorylation of NF observed in this study corroborates with the earlier observations in human leprous nerves.

Prevalence and pattern of cross-reacting antibodies to HIV in patients with tuberculosis.

In many countries, HIV testing among tuberculosis (TB) patients is recommended so that both infections are appropriately treated. Cross-reacting antibodies to HIV antigens have been reported for several conditions, including TB, leprosy, malaria, and rheumatoid arthritis. To study the pattern and prevalence of cross-reacting antibodies to HIV antigens, we examined sera from 153 HIV-negative TB patients and 40 healthy individuals in Chennai, south India. We also studied the differences in cross-reactivity of various HIV antigens using two different Western blot kits. Of the 153 samples studied, 80 were tested using HIV Western blot and 73 were tested using INNOLIA. Most patients in the study had concordantly negative ELISA and rapid tests, and no subject had a positive Western blot. However, seven TB patients had antibodies that cross-reacted with HIV antigens, giving rise to an indeterminate result. While p51/55 was the most frequently recognized antigen in the Western blot assay, antibodies to sgp120 was most frequently identified in INNOLIA. Sequence similarities between the two organisms could be responsible for eliciting cross-reacting antibodies, since a few related epitopes were identified in HIV and Mycobacterium. These findings could have potential implications for the development of diagnostics and vaccines.