Detection of Mycobacterium leprae antigens in the sera of leprosy patients by sandwich immunoradiometric assay using monoclonal antibodies.

SummaryTwo monoclonal antibodies raised against FVIII/von Willebrand protein were used in an immunoradiometric assay (IRMA) to measure this antigen in normal plasma and plasma of patients with different forms of von Willebrand’s disease. The first antibody, an IgG1 was used to coat polystyrene tubes, the second one, an IgG2a, iodinated and used in the second step. Both antibodies inhibit ristocetin induced platelet agglutination and react strongly with platelets, megacaryocytes and endothelial cells. The IRMA test using these antibodies showed greater sensitivity than that using rabbit polyclonal anti VIIIRAg antibodies. A good correlation between the two tests was nevertheless found when VIIIRAg was measured in the majority of patient’s plasma. However 5 patients from 3 different families showed more antigenic material in the rabbit antibody IRMA than in the monoclonal antibody IRMA. It is suggested therefore that the monoclonal antibodies identify part of the VIIIR:Ag molecule showing structural abnormalities in these vWd patients, these structural changes remaining undetected by the polyclonal antibodies.

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Recent Advancement in the Diagnosis and Treatment of Leprosy

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666181025100434 ◽

2018 ◽

Vol 18 (18) ◽

pp. 1550-1558

Author(s):

Muhammad Aamir ◽

Asma Sadaf ◽

Sehroon Khan ◽

Shagufta Perveen ◽

Afsar Khan

Keyword(s):

Vitamin D ◽

Drug Treatment ◽

Mycobacterium Leprae ◽

Neglected Diseases ◽

Specific Drug ◽

Genetic Studies ◽

Vitamin D Receptors ◽

Micro Rnas ◽

Leprosy Patients ◽

Skin Biopsies

Background: Many of the tropical diseases are neglected by the researchers and medicinal companies due to lack of profit and other interests. The Drugs for Neglected Diseases initiative (DNDi) is established to overcome the problems associated with these neglected diseases. According to a report published by the WHO, leprosy (Hansen's disease) is also a neglected infectious disease. Methods: A negligible amount of advancements has been made in last few decades which includes the tools of diagnosis, causes, treatment, and genetic studies of the bacterium (Mycobacterium leprae) that causes leprosy. The diagnosis of leprosy at earlier stages is important for its effective treatment. Recent studies on vitamin D and its receptors make leprosy diagnosis easier at earlier stages. Skin biopsies and qPCR are the other tools to identify the disease at its initial stages. Results: Until now a specific drug for the treatment of leprosy is not available, therefore, Multi-Drug Therapy (MDT) is used, which is hazardous to health. Besides Mycobacterium leprae, recently a new bacterium Mycobacterium lepromatosis was also identified as a cause of leprosy. During the last few years the genetic studies of Mycobacterium leprae, the role of vitamin D and vitamin D receptors (VDR), and the skin biopsies made the treatment and diagnosis of leprosy easier at early stages. The studies of micro RNAs (miRNAs) made it easy to differentiate leprosy from other diseases especially from tuberculosis. Conclusion: Leprosy can be distinguished from sarcoidosis by quantitative study of reticulin fibers present in skin. The treatment used until now for leprosy is multi-drug treatment. The complete genome identification of Mycobacterium leprae makes the research easy to develop target specified drugs for leprosy. Rifampicin, identified as a potent drug, along with other drugs in uniform multi-drug treatment, has a significant effect when given to leprosy patients at initial stages. These are effective treatments but a specific drug for leprosy is still needed to be identified. The current review highlights the use of modern methods for the identification of leprosy at its earlier stages and the effective use of drugs alone as well as in combination.

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Recombinant polypeptide of Mycobacterium leprae as a potential tool for serological detection of leprosy

AMB Express ◽

10.1186/s13568-019-0928-9 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Marcelo dos Santos Barbosa ◽

Iara Beatriz Andrade de Sousa ◽

Simone Simionatto ◽

Sibele Borsuk ◽

Silvana Beutinger Marchioro

Keyword(s):

Large Scale ◽

Mycobacterium Leprae ◽

Detection Methods ◽

Recombinant Polypeptide ◽

Cell Reactivity ◽

Tertiary Structures ◽

Leprosy Patients ◽

T Cell Reactivity ◽

Prevention Methods ◽

Scale Detection

AbstractCurrent prevention methods for the transmission of Mycobacterium leprae, the causative agent of leprosy, are inadequate as suggested by the rate of new leprosy cases reported. Simple large-scale detection methods for M. leprae infection are crucial for early detection of leprosy and disease control. The present study investigates the production and seroreactivity of a recombinant polypeptide composed of various M. leprae protein epitopes. The structural and physicochemical parameters of this construction were assessed using in silico tools. Parameters like subcellular localization, presence of signal peptide, primary, secondary, and tertiary structures, and 3D model were ascertained using several bioinformatics tools. The resultant purified recombinant polypeptide, designated rMLP15, is composed of 15 peptides from six selected M. leprae proteins (ML1358, ML2055, ML0885, ML1811, ML1812, and ML1214) that induce T cell reactivity in leprosy patients from different hyperendemic regions. Using rMLP15 as the antigen, sera from 24 positive patients and 14 healthy controls were evaluated for reactivity via ELISA. ELISA-rMLP15 was able to diagnose 79.17% of leprosy patients with a specificity of 92.86%. rMLP15 was also able to detect the multibacillary and paucibacillary patients in the same proportions, a desirable addition in the leprosy diagnosis. These results summarily indicate the utility of the recombinant protein rMLP15 in the diagnosis of leprosy and the future development of a viable screening test.

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Genotyping of Mycobacterium leprae present on Ziehl-Neelsen-stained microscopic slides and in skin biopsy samples from leprosy patients in different geographic regions of Brazil

Memórias do Instituto Oswaldo Cruz ◽

10.1590/s0074-02762012000900021 ◽

2012 ◽

Vol 107 (suppl 1) ◽

pp. 143-149 ◽

Cited By ~ 13

Author(s):

Amanda Nogueira Brum Fontes ◽

Harrison Magdinier Gomes ◽

Marcelo Ivens de Araujo ◽

Edson Cláudio Araripe de Albuquerque ◽

Ida Maria Foschiani Dias Baptista ◽

...

Keyword(s):

Skin Biopsy ◽

Mycobacterium Leprae ◽

Leprosy Patients ◽

Geographic Regions

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Most Mycobacterium leprae carbohydrate-reactive monoclonal antibodies are directed to lipoarabinomannan.

Infection and Immunity ◽

10.1128/iai.55.11.2860-2863.1987 ◽

1987 ◽

Vol 55 (11) ◽

pp. 2860-2863 ◽

Cited By ~ 32

Author(s):

H Gaylord ◽

P J Brennan ◽

D B Young ◽

T M Buchanan

Keyword(s):

Monoclonal Antibodies ◽

Mycobacterium Leprae

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Characterization and Use in Immunoradiometric Assay of Monoclonal Antibodies Directed Against Human Proinsulin

Diabetes ◽

10.2337/diab.36.6.684 ◽

1987 ◽

Vol 36 (6) ◽

pp. 684-688 ◽

Cited By ~ 7

Author(s):

I. P. Gray ◽

K. Siddle ◽

B. H. Frank ◽

C. N. Hales

Keyword(s):

Monoclonal Antibodies ◽

Immunoradiometric Assay ◽

Human Proinsulin

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Analysis of the Myeloid-Derived Suppressor Cells and Annexin A1 in Multibacillary Leprosy and Reactional Episodes

10.21203/rs.3.rs-126210/v1 ◽

2020 ◽

Author(s):

Amilcar Sabino Damazo ◽

Stephanni Figueiredo da Silva ◽

Leticia Rossetto da Silva Cavalcante ◽

Ezequiel Angelo Fonseca Junior ◽

Joselina Maria da Silva ◽

...

Keyword(s):

Suppressor Cells ◽

Suppressor Cell ◽

Mycobacterium Leprae ◽

Histopathological Analysis ◽

Annexin A1 ◽

Myeloid Derived Suppressor Cells ◽

Myeloid Derived Suppressor Cell ◽

Leprosy Patients ◽

Multibacillary Leprosy

Abstract Background: Leprosy is a chronic infectious disease caused by Mycobacterium leprae. Patients have distinct clinical forms, and host´s immunological response regulate those manifestations. In this work, the presence of the myeloid-derived suppressor cell and the regulatory protein annexin A1 is described in patients with multibacillary leprosy and with type 1 and 2 reactions. Methods: Patients were submitted to skin biopsy for histopathological analysis to obtain bacilloscopic index. Immunofluorescence was used to detect myeloid-derived suppressor cells and annexin A1.Results: The data demonstrated that the presence of granulocytic and monocytic myeloid-derived suppressor cells in leprosy patients. The high number of monocytic myeloid-derived suppressor cells were observed in lepromatous leprosy and type 2 reactional patients with Bacillus Calmette–Guérin (BCG) vaccination scar. The presence of annexin A1 was observed in all myeloid-derived suppressor cells. In particularly, the monocytic myeloid-derived suppressor cell in the lepromatous patients has higher levels of this protein when compared to the reactional patients. This data suggest that the higher expression of this protein may be related to regulatory response against a severe infection, contributing to anergic response. In type 1 reactional patients, the expression of annexin A1 was reduced. Conclusions: Myeloid-derived suppressor cell are present in leprosy patients and annexin A1 might be regulated the host response against Mycobacterium leprae.

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