Research Projects:

1. Molecular Epidemiology of Post Kala-Azar Dermal Leishmaniasis in eastern Sudan. Supported by TDR/ South-South initiative grant.

In collaboration with Dr. Ikram Guizani Institute Pasteur Tunisia

Summary:

A previous TDR/ PAG- collaborative study, using isoenzymes and DNA based tools, identified L. archibaldi as a predominant etiological agent of Visceral Leishmaniasis (VL) and Post Kala azar Dermal Leismaniasis (PKDL) cases in Sudan. This proposal intends to validate these findings and aims at setting a rationale basis for improving measures for the control of VL, epidemic in Sudan. Different working hypotheses were developed and will be addressed through the collection of samples and parasite isolations at different time points during the disease: before and after treatment and when PKDL develops, in order to identify parasite haplotypes correlated with PKDL development. Tools that will allow the identification and/or analysis of parasite diversity in DNAs extracted from promastigotes and from infected patients will be applied. Prognostic markers for PKDL development will be identified using a RAPD based approach and Leishmania genome ressources. PCR- based DNA tools will be developed and subsequently validated and applied. Parasite diversity will be evaluated, haplotypes identified, populations structures assessed and correlation with clinical stages defined. This collaborative project between Institut Pasteur de Tunis, Institute of Endemic Diseases and Fundaçao Oswaldo Cruz brings together complementary expertise and shared interests, allows technology transfer and training, and provides the basis for sustainable and long-term collaboration.

2. The burden of tuberculosis in eastern Sudan: Epidemiology and drug resistance patterns of mycobacterium tuberculosis

Supported by EDCTP senior fellowship award

Code 2004.2.C.f1

Investigator: Professor Maowia M. Mukhtar

Title:

The burden of Tuberculosis in eastern Sudan: Epidemiology and drug resistance patterns of Mycobacterium tuberculosis isolates.     

Summary:

Sudan is the largest country in Africa. The low national income, the meager resources, the civil unrest and the displacement of population has complicated the health problems and helped in the spread of diseases.

Tuberculosis is a growing health problem in Sudan. Unlike other subsaharan African countries, the increase in the incidence of TB in Sudan is not associated with the current spread of HIV infection. A few studies were conducted on the epidemiology of TB in Sudan and little inforamtion is available about the burdern of TB, and the extent of TB  drug resistance.

The Institute of Endemic Diseases is a leading national research and training center and has been involved in several studies on endemic and infectious diseases. The Staff of the institute have accumulated valuable experience on both basic research and clinical trials.

The Department of Public Health, Leopold institue of Tropical Medicine, Belgium; has a strong experience and interest in epidemiology and health system research of Tuberculosis. Such experience is complementary to the clinical and laboratory experience available in the institute of Endemic Diseases.

The objectives of this proposal are: to study and map the burden of Tuberculosis in eastern Sudan, to undestand the epidemiology of pulmonary TB and to determine the drug resistance patterns of MTB isolates. The study is expected to result in generation of basic data that could be used in future, diagnostic, treatment and vaccine testing.

A community based study will be conducted in TB endemic region in eastern Sudan. Multistage sampling design will be used for selection of the study subjects. Based on current regional hospital record with expected TB prevalence of 0.5%, 100 villages will be randomly selected from five geographical regions, and 100 households will be randomly selected from each village resulting in recruitment of about 70,000 indiviualds. Suspected TB patients will be identifed by direct interviews of househods based on presentation of family members with cough >3 weeks, contact with TB index case, and suspected TB clinical signs in children. TB patients under current treatment and efuaters will also be identified and recruited. TB infection will be confirmed by clinical examination, chest X-ray and detection of acid fast baccilli in three consecutive sputum samples. Mycobacterium will be isolated using both liquid media culturing system and conventional culture methods.

The isolates will be typed and characterized based on PCR amplification and Retriction Fragment Length Polymorphism (RFLP) of the rpoB and the IS6110 DNA sequence of isolates. The sensitivity of selected isolates to Isoniazed and Rifampicin will be tested using invirto sensitivity tests. Prevalence of multi drug resistance among the isolates will be determined based on PCR amplification and restriction of the rpoB gene.

Association between possible risk factors inculding: age, gender, socioeconomic status, nutritional status, and TB will be determined. The health seeking behavior of TB patients/ or their guardians will be studied.

Data will be computed and GIS maps for the prevalence of TB, drug resistance, risk factors, health facilties and roads will be created using ArcView GIS computer software.

3. Proteomics of the urine of Kala-Azar patients.

Supported by ICGEB Grant

Abstract:

Visceral Leishmaniasis (Kala-Azar) is a serious health problem in more than 88 countries world wide. The majority of infected individuals remain a symptomatic with and annual clinical incidence of 500,000 patients. 90% of clinical patients live in poor endemic areas in Sudan and India. Visceral Leishmaniasis if fatal if not treated, and the current control programs are based on active case detection and treatment. Diagnosis of VL is based on detection of parasites (invasive and of low sensitivity), detection of parasite specific antibodies using different serological tests (tests have variable sensitivities specially in Leishmania/ HIV co-infected patients and can not differentiate between current and historical infection). Molecular technology that provided sensitive tests (need specialized laboratory facilities and trained personnel difficult to maintain in endemic areas).  

Several studies confirmed the secretion of parasite antigens in patient’s urine. Detection of parasite antigens in patient’s urine can provide a simple noninvasive, sensitive and specific diagnostic test that can differentiate between current and historical infections and will enable the diagnosis of Leishmania/ HIV co-infected patients.

Parasite antigens will be detected in patient’s urine compared with healthy control urine using (2D) two dimensional gel electrophoresis followed by staining with silver and Sypro Ruby stains. The parasite specific spots will be characterized by mass spectrometry technology. The immunological reactive spots will be identified using western blotting. Identified antigens will be cloned, expressed and evaluated for diagnostic value using confirmed VL urine compared with urine of healthy endemic controls.

4. Immune responses and HLA typing of mycetoma patients. Supported by local fund

5. Biotechnological characterization of Leishmania isolates from different clinical forms.
Supported by WHO/ TDR grant

6. Biomarkers of Mycobacterium tuberculosis in urine and sputum of pulmonary TB patients

Supported by Find/ TDR grant

Summary:

This study aims to identify and characterize Mycobacterium tuberculosis antigens in sputum and urine of TB patients using proteomics technology.

Samples will be collected from microscopically confirmed TB patients and normal controls. The samples will be separated using one and two dimensional (2D) gel electrophoresis (2DE).  Mycobacterium specific protein unique in the sputum and urine of TB patients will be identified and characterized using mass -spectrometry. Identified proteins will be characterized using the Profound search engine and compared with proteins published in Swissprot and NCBI

The proteins will be tested for immunological reactivity and evaluated for diagnostic value.

7. Cellular immune response in dermal Leishmaniasis (in collaboration with Professor J. Louis, Pasteur Institute, Dr. Pascal , WHO immunology research and training center, lausanne, Switzerland; Dr. Nancy Saravia Columbia and Dr. Kuossay. Dalaji, Pasteur Institute Tunisia) supported by IBS, Switzerland