scholarly journals Urine-Based Antigen (Protein) Detection Test for the Diagnosis of Visceral Leishmaniasis

2020 ◽  
Vol 8 (11) ◽  
pp. 1676
Author(s):  
Antonio Campos-Neto ◽  
Claudia Abeijon
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Donovani ◽  
Protein Detection ◽  
Standard Test ◽  
Antigen Detection ◽  
Serological Tests ◽  
Latex Beads ◽  
Antigen Protein ◽  
Etiological Agents ◽  
Novel Protein

This review describes and appraises a novel protein-based antigen detection test for visceral leishmaniasis (VL). The test detects in patient’s urine six proteins from Leishmania infantum (chagasi) and Leishmania donovani, the etiological agents of VL. The gold standard test for VL is microscopic observation of the parasites in aspirates from spleen, liver, or bone marrow (and lymph node for dogs). Culture of the parasites or detection of their DNA in these aspirates are also commonly used. Serological tests are available but they cannot distinguish patients with active VL from either healthy subjects exposed to the parasites or from subjects who had a successful VL treatment. An antigen detection test based on the agglutination of anti-leishmania carbohydrates antibody coated latex beads has been described. However, the results obtained with this carbohydrate-based test have been conflicting. Using mass spectrometry, we discovered six L. infantum/L. donovani proteins excreted in the urine of VL patients and used them as markers for the development of a robust mAb-based antigen (protein) detection test. The test is assembled in a multiplexed format to simultaneously detect all six markers. Its initial clinical validation showed a sensitivity of 93% and specificity of 100% for VL diagnosis.

Assessment of a New Antigen Detection Test for the Diagnosis of Canine Visceral Leishmaniasis

2021 ◽  
Author(s):  
Claudia Abeijon ◽  
Stefano Pizzirani ◽  
Antonio Campos-Neto
Keyword(s):  
Bone Marrow ◽  
Visceral Leishmaniasis ◽  
Protein Detection ◽  
Antigen Detection ◽  
Canine Visceral Leishmaniasis ◽  
Chain Reaction ◽  
Serological Tests ◽  
Polymerase Chain ◽  
Antigen Protein ◽  
Simple Exposure

Canine visceral leishmaniasis (CVL) is a serious zoonotic disease in Brazil and Southern Europe. CVL is primarily caused by Leishmania infantum and its diagnosis relies primarily on detection of parasites in bone marrow or lymph node aspirates by microscopic observation of the parasites in stained smears, parasite culture, or polymerase chain reaction (PCR). Serological tests exist but they do not distinguish active disease from simple exposure to parasite antigens. Here, we have assessed the utility of a new monoclonal antibody––based antigen (protein) detection test for the diagnosis of CVL. The test was positive in 70% of beagle dogs experimentally infected with L. infantum. In contrast, culture of the parasites from bone marrow aspirates was positive in only 40% of the infected animals. These preliminary results suggest that this antigen detection test, which we have recently described for the diagnosis of human VL, has the potential to be a useful diagnostic tool for CVL.

scholarly journals Development of a Multiplexed Assay for Detection ofLeishmania donovaniandLeishmania infantumProtein Biomarkers in Urine Samples of Patients with Visceral Leishmaniasis

2019 ◽  
Vol 57 (5) ◽  
Author(s):  
Claudia Abeijon ◽  
Fabiana Alves ◽  
Severine Monnerat ◽  
Monique Wasunna ◽  
Jane Mbui ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Diagnostic Test ◽  
Leishmania Donovani ◽  
Protein Biomarkers ◽  
Serological Tests ◽  
Assay Sensitivity ◽  
Content Type ◽  
Detection Assay ◽  
Previously Treated ◽  
New Biomarkers

ABSTRACTVisceral leishmaniasis (VL) is a serious and fatal disease caused by the parasitesLeishmania infantumandLeishmania donovani. The gold standard diagnostic test for VL is the demonstration of parasites or their DNA in spleen, lymph node, or bone marrow aspirates. Serological tests exist but cannot distinguish active VL from either prior exposure to the parasites or previously treated VL disease. Using mass spectroscopy, we have previously identified threeL. infantumprotein biomarkers (Li-isd1,Li-txn1, andLi-ntf2) in the urine of VL patients and developed a sensitive and specific urine-based antigen detection assay for the diagnosis of VL that occurs in Brazil (where VL is caused byL. infantum). However, unpublished observations from our laboratory at DetectoGen showed that these biomarkers were detected in only 55% to 60% of VL patients from India and Kenya, where the disease is caused byL. donovani. Here, we report the discovery and characterization of two new biomarkers ofL. donovani(Ld-mao1andLd-ppi1) present in the urine of VL patients from these two countries. Capture enzyme-linked immunosorbent assays using specific rabbit IgG and chicken IgY were developed, and the assays had sensitivities of 44.4% and 28.8% for the detection ofLd-mao1andLd-ppi1, respectively. In contrast, a multiplexed assay designed to simultaneously detect all five leishmanial biomarkers markedly increased the assay sensitivity to 82.2%. These results validate the utility of leishmanial protein biomarkers found in the urine of VL patients as powerful tools for the development of an accurate diagnostic test for this disease.

scholarly journals Heterogeneity of Leishmania donovani Parasites Complicates Diagnosis of Visceral Leishmaniasis: Comparison of Different Serological Tests in Three Endemic Regions

PLoS ONE ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. e0116408 ◽  
Author(s):  
Elfadil Abass ◽  
Cholho Kang ◽  
Franjo Martinkovic ◽  
Saul J. Semião-Santos ◽  
Shyam Sundar ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Donovani ◽  
Serological Tests

Visceral leishmaniasis: a forgotten epidemic

2016 ◽  
Vol 101 (6) ◽  
pp. 561-567 ◽  
Author(s):  
Eduard E Zijlstra
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Donovani ◽  
Immunosuppressive Drugs ◽  
Diagnostic Tools ◽  
Bed Nets ◽  
Sand Flies ◽  
Serological Tests ◽  
Kala Azar ◽  
Younger Age ◽  
Strip Test

Visceral leishmaniasis (VL or kala-azar) is most endemic in Asia and Africa and commonly affects young children. It is usually caused byLeishmania donovaniorLeishmania infantumthat are transmitted by Phlebotomine sand flies. Transmission may be anthroponotic or zoonotic or both, depending on the endemic area. Clinical features include fever, hepatosplenomegaly, weight loss and pancytopenia. Younger age, malnutrition and immunosuppression (HIV infection, use of immunosuppressive drugs) are risk factors. Many infections remain asymptomatic. Diagnosis is made by demonstration of theLeishmaniaparasite in aspirates of lymph node, bone marrow or spleen. Serological tests such as rK39 strip test are widely used but the sensitivity varies. qPCR is useful to detect low numbers of parasites and to monitor treatment. Treatment is with AmBisome monotherapy in most areas but with drug combinations elsewhere. HIV co-infected patients are most difficult to treat and often relapse. Control efforts focus on case finding, availability of diagnostic tools, reservoir control and protection from sand flies (insecticides, bed nets). There is no human vaccine.

scholarly journals The Treatment of Visceral Leishmaniasis: Safety and Efficacy

2013 ◽  
Vol 52 (192) ◽  
Author(s):  
Rajesh Kumar Jha ◽  
Ajit Kumar Sah ◽  
Dev Kumar Shah ◽  
Phoolgen Sah
Keyword(s):  
Visceral Leishmaniasis ◽  
Amphotericin B ◽  
Leishmania Donovani ◽  
Adverse Drug Events ◽  
Serological Tests ◽  
Socioeconomic Condition ◽  
First Line Therapy ◽  
Line Therapy ◽  
Pentavalent Antimony ◽  
Almost All

Visceral leishmaniasis is the disease of poor; however availability of only expensive treatment of this disease impinges the socioeconomic condition of those affected. If untreated, almost all cases of visceral leishmaniasis are fatal. The demonstration of the leishmania donovani bodies from the tissue aspirates or serological tests confirms the diagnosis of the disease. Pentavalent antimony, amphotericin B, paromomycin, diamine pentamidine, miltefosine, sitamaquine and some new combinations are integrated in the limited therapeutic armoury for treatment of visceral leishmaniasis. The recommended first and second line therapy in the Indian sub-continent is miltefosine and amphotericin B respectively.Pentavalent antimonial, preceding first line therapy, has been replaced by miltefosine due to former increasing failure rate and toxicity.The problem of drug resistance, some of the serious drug toxicities along with high-priced drugs extends challenges equally to pharmaceutical companies and medical practitioners.More research on adverse drug events for the existing drugs and efforts to develop safer and effective drugs to counter resistance outbreaks for the successful management of visceral leishmaniasis are needed.  Keywords: amphotericin; miltefosine; pentavalent antimony; paromomycin.    

scholarly journals The increased presence of repetitive motifs in the KDDR-plus recombinant protein, a kinesin-derived antigen from Leishmania infantum, improves the diagnostic performance of serological tests for human and canine visceral leishmaniasis

2021 ◽  
Vol 15 (9) ◽  
pp. e0009759
Author(s):  
Williane Fernanda Siqueira ◽  
Agostinho Gonçalves Viana ◽  
João Luís Reis Cunha ◽  
Leticia Mansur Rosa ◽  
Lilian Lacerda Bueno ◽  
...  
Keyword(s):  
Amino Acid ◽  
Visceral Leishmaniasis ◽  
Diagnostic Performance ◽  
Leishmania Donovani ◽  
Protein A ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Tests ◽  
Appropriate Treatment ◽  
Human Sera ◽  
Fatal Form

Visceral leishmaniasis (VL) is caused by protozoa belonging to the Leishmania donovani complex and is considered the most serious and fatal form among the different types of leishmaniasis, if not early diagnosed and treated. Among the measures of disease control stand out the management of infected dogs and the early diagnosis and appropriate treatment of human cases. Several antigens have been characterized for use in the VL diagnosis, among them are the recombinant kinesin-derived antigens from L. infantum, as rK39 and rKDDR. The main difference between these antigens is the size of the non-repetitive kinesin region and the number of repetitions of the 39 amino acid degenerate motif (6.5 and 8.5 repeats in rK39 and rKDDR, respectively). This repetitive region has a high antigenicity score. To evaluate the effect of increasing the number of repeats on diagnostic performance, we designed the rKDDR-plus antigen, containing 15.3 repeats of the 39 amino acid degenerate motif, besides the absence of the non-repetitive portion from L. infantum kinesin. Its performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and rapid immunochromatographic test (ICT), and compared with the kinesin-derived antigens (rKDDR and rK39). In ELISA with human sera, all recombinant antigens had a sensitivity of 98%, whereas the specificity for rKDDR-plus, rKDDR and rK39 was 100%, 96% and 71%, respectively. When evaluated canine sera, the ELISA sensitivity was 97% for all antigens, and the specificity for rKDDR-plus, rKDDR and rK39 was 98%, 91% and 83%, respectively. Evaluation of the ICT/rKDDR-plus, using human sera, showed greater diagnostic sensitivity (90%) and specificity (100%), when compared to the IT LEISH (79% and 98%, respectively), which is based on the rK39 antigen. These results suggest that the increased presence of repetitive motifs in the rKDDR-plus protein improves the diagnostic performance of serological tests by increasing the specificity and accuracy of the diagnosis.

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