Leishmania tarentolae and Leishmania infantum in humans, dogs and cats in the Pelagie archipelago, southern Italy

Visceral leishmaniasis (VL) caused by Leishmania infantum is endemic in the Mediterranean basin with most of the infected human patients remaining asymptomatic. Recently, the saurian-associated Leishmania tarentolae was detected in human blood donors and in sheltered dogs. The circulation of L. infantum and L. tarentolae was investigated in humans, dogs and cats living in the Pelagie islands (Sicily, Italy) by multiple serological and molecular testing. Human serum samples (n = 346) were tested to assess the exposure to L. infantum by immunofluorescence antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) and to L. tarentolae by IFAT. Meanwhile, sera from dogs (n = 149) and cats (n = 32) were tested for both Leishmania species by IFAT and all blood samples by specific sets of real time-PCR for L. infantum and L. tarentolae. The agreement between serological tests performed for human samples, and between serological and molecular diagnostic techniques for both human and animal samples were also assessed. Overall, 41 human samples (11.8%, 95% CI: 8.9–15.7) were positive to L. infantum (5.2%, 95% CI: 3.3–8.1), L. tarentolae (5.2%, 95% CI: 3.3–8.1) and to both species (1.4%, 95% CI: 0.6–3.3) by serology and/or molecular tests. A good agreement among the serological tests was determined. Both Leishmania spp. were serologically and/or molecularly detected in 39.6% dogs and 43.7% cats. In addition to L. infantum, also L. tarentolae circulates in human and animal populations, raising relevant public health implications. Further studies should investigate the potential beneficial effects of L. tarentolae in the protection against L. infantum infection.

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Evaluation of the performance of three serological tests for diagnosis of Leishmania infantum infection in dogs using latent class analysis

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612020105 ◽

2020 ◽

Vol 29 (4) ◽

Author(s):

Asier Basurco ◽

Alda Natale ◽

Katia Capello ◽

Antonio Fernández ◽

María Teresa Verde ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Leishmania Infantum ◽

Latent Class ◽

Rapid Test ◽

Antibody Test ◽

Latent Class Models ◽

Canine Leishmaniasis ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Serological Tests

Abstract Canine leishmaniasis (CanL) is a disease caused by Leishmania infantum. Serological methods are the most common diagnostic techniques used for the diagnosis of the CanL. The objective of our study was to estimate the sensitivity and specificity of one in-house ELISA kit (ELISA UNIZAR) and three commercially available serological tests (MEGACOR Diagnostik GmbH) including an immunochromatographic rapid test (FASTest LEISH®), an immunofluorescent antibody test (MegaFLUO LEISH®) and an enzyme-linked immunosorbent assay (MegaELISA LEISH®), using latent class models in a Bayesian analysis. Two hundred fifteen serum samples were included. The highest sensitivity was achieved for FASTest LEISH® (99.38%), ELISA UNIZAR (99.37%), MegaFLUO LEISH® (99.36%) followed by MegaELISA LEISH® (98.49%). The best specificity was obtained by FASTest LEISH® (98.43%), followed by ELISA UNIZAR (97.50%), whilst MegaFLUO LEISH® and MegaELISA LEISH® obtained the lower specificity (91.94% and 91.93%, respectively). The results of present study indicate that the immunochromatographic rapid test evaluated FASTest LEISH® show similar levels of sensitivity and specificity to the quantitative commercial tests. Among quantitative serological tests, sensitivity and specificity were similar considering ELISA or IFAT techniques.

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Canine visceral leishmaniasis in the Krenak indigenous community, Resplendor, Minas Gerais State, Brazil, 2007

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2011000300020 ◽

2011 ◽

Vol 27 (3) ◽

pp. 603-607 ◽

Cited By ~ 1

Author(s):

Eloiza Gonçalves Antônio ◽

Marcos Aurélio Fulgêncio Malacco ◽

Célia Maria Ferreira Gontijo ◽

Eliana Furtado Moreira ◽

Ivo Santana Caldas ◽

...

Keyword(s):

Diagnostic Techniques ◽

Cross Sectional Study ◽

Indigenous Community ◽

Molecular Diagnostic ◽

Molecular Diagnostic Techniques ◽

Sectional Study ◽

Serum Samples ◽

Serological Tests ◽

Cross Sectional ◽

Canine Infection

The authors conducted a cross-sectional study of the local canine population in the Krenak indigenous community to detect parasites of the genus Leishmania and identify the circulating species and the proportion of asymptomatic dogs, while investigating associations between canine infection and the dogs' sex, age, and hair length. A seroepidemiological survey was performed, including 63 dogs. All the animals underwent clinical examination to verify the presence of characteristic signs, and serum samples were taken for serological tests (ELISA, IIF). Infected dogs culled by the health service were necropsied and the material was analyzed using molecular diagnostic techniques. The cross-sectional study detected a 46% prevalence rate, and the circulating species was Leishmania (L.) chagasi. The statistical analysis showed no association between infection and the independent variables. The study generated data on the epidemiological situation with canine infection in the area, which was previously unknown.

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Serological Evaluation of Specific-Antibody Levels in Patients Treated for Chronic Chagas' Disease

Clinical and Vaccine Immunology ◽

10.1128/cvi.00106-07 ◽

2007 ◽

Vol 15 (2) ◽

pp. 297-302 ◽

Cited By ~ 38

Author(s):

Olga Sánchez Negrette ◽

Fernando J. Sánchez Valdéz ◽

Carlos D. Lacunza ◽

María Fernanda García Bustos ◽

María Celia Mora ◽

...

Keyword(s):

Chagas Disease ◽

Treatment Effectiveness ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Serological Tests ◽

Recombinant Antigens ◽

Antibody Titers ◽

Laboratory Procedures ◽

The Individual ◽

Antibody Levels

ABSTRACT Serological tests are the main laboratory procedures used for diagnosis during the indeterminate and chronic stages of Chagas' disease. A serological regression to negativity is the main criterion used to define parasitological cure in treated patients. The aim of this work was to monitor the individual specificities of antibody levels for 3 years posttreatment in 18 adult patients. Conventional serological techniques (hemagglutination assays and enzyme-linked immunosorbent assay [ELISA]) were modified by using recombinant antigens to detect early markers of treatment effectiveness. For this purpose, serum samples were taken before and during treatment and every 6 months after treatment for at least 3 years. When hemagglutination assays were used, a decrease in antibody levels was observed in only one patient. When ELISA with serum dilutions was used, antibody clearance became much more apparent: in 77.7% (14/18) of the patients, antibody titers became negative with time. This was observed at serum dilutions of 1/320 and occurred between the 6th and the 30th months posttreatment. The immune response and the interval for a serological regression to negativity were different for each patient. For some of the recombinant antigens, only 50% (9/18) of the patients reached the serological regression to negativity. Recombinant antigen 13 might be a good marker of treatment effectiveness, since 66.6% (six of nine) of the patients presented with an early regression to negativity for specific antibodies to this antigen (P = 0.002).

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Epidemic Preparedness—Leishmania tarentolae as an Easy-to-Handle Tool to Produce Antigens for Viral Diagnosis: Application to COVID-19

Frontiers in Microbiology ◽

10.3389/fmicb.2021.736530 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ilaria Varotto-Boccazzi ◽

Alessandro Manenti ◽

Francesca Dapporto ◽

Louise J. Gourlay ◽

Beatrice Bisaglia ◽

...

Keyword(s):

Rapid Development ◽

Antibody Detection ◽

Molecular Diagnostic ◽

Serological Tests ◽

Leishmania Tarentolae ◽

Cell Factories ◽

Effective System ◽

Human Sera ◽

Antiviral Antibody ◽

Viral Diagnosis

To detect and prevent emerging epidemics, discovery platforms are urgently needed, for the rapid development of diagnostic assays. Molecular diagnostic tests for COVID-19 were developed shortly after the isolation of SARS-CoV-2. However, serological tests based on antiviral antibody detection, revealing previous exposure to the virus, required longer testing phases, due to the need to obtain correctly folded and glycosylated antigens. The delay between the identification of a new virus and the development of reliable serodiagnostic tools limits our readiness to tackle future epidemics. We suggest that the protozoan Leishmania tarentolae can be used as an easy-to-handle microfactory for the rapid production of viral antigens to face emerging epidemics. We engineered L. tarentolae to express the SARS-CoV-2 receptor-binding domain (RBD) and we recorded the ability of the purified RBD antigen to detect SARS-CoV-2 infection in human sera, with a sensitivity and reproducibility comparable to that of a reference antigen produced in human cells. This is the first application of an antigen produced in L. tarentolae for the serodiagnosis of a Coronaviridae infection. On the basis of our results, we propose L. tarentolae as an effective system for viral antigen production, even in countries that lack high-technology cell factories.

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Serodiagnosis of Louse-Borne Relapsing Fever with Glycerophosphodiester Phosphodiesterase (GlpQ) fromBorrelia recurrentis

Journal of Clinical Microbiology ◽

10.1128/jcm.38.10.3561-3571.2000 ◽

2000 ◽

Vol 38 (10) ◽

pp. 3561-3571 ◽

Cited By ~ 54

Author(s):

Stephen F. Porcella ◽

Sandra J. Raffel ◽

Merry E. Schrumpf ◽

Martin E. Schriefer ◽

David T. Dennis ◽

...

Keyword(s):

Serological Test ◽

Geometric Mean ◽

Eastern Africa ◽

Enzyme Linked Immunosorbent Assay ◽

Relapsing Fever ◽

Serum Samples ◽

Serological Tests ◽

Whole Cell ◽

Convalescent Phase ◽

Glycerophosphodiester Phosphodiesterase

Human louse-borne relapsing fever occurs in sporadic outbreaks in central and eastern Africa that are characterized by significant morbidity and mortality. Isolates of the causative agent,Borrelia recurrentis, were obtained from the blood of four patients during a recent epidemic of the disease in southern Sudan. TheglpQ gene, encoding glycerophosphodiester phosphodiesterase, from these isolates was sequenced and compared with the glpQ sequences obtained from other relapsing-fever spirochetes. Previously we showed that GlpQ of Borrelia hermsii is an immunogenic protein with utility as a serological test antigen for discriminating tick-borne relapsing fever from Lyme disease. In the present work, we cloned and expressed theglpQ gene from B. recurrentis and used recombinant GlpQ in serological tests. Acute- and convalescent-phase serum samples obtained from 42 patients with louse-borne relapsing fever were tested with an indirect immunofluorescence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA) that used whole cells ofB. recurrentis and with immunoblotting to whole-cell lysates of the spirochete and Escherichia coli producing recombinant GlpQ. The geometric mean titers of the acute- and convalescent-phase serum samples measured by IFA were 1:83 and 1:575, respectively. The immunoblot analysis identified a high level of reactivity and seroconversion to GlpQ, and the assay was more sensitive than the whole-cell IFA and ELISA using purified, recombinant histidine-tagged GlpQ. Serum antibodies to GlpQ and other antigens persisted for 27 years in one patient. We conclude that assessment of anti-GlpQ antibodies will allow serological confirmation of louse-borne relapsing fever and determination of disease prevalence.

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Subtractive Phage Display Selection from Canine Visceral Leishmaniasis Identifies Novel Epitopes That Mimic Leishmania infantum Antigens with Potential Serodiagnosis Applications

Clinical and Vaccine Immunology ◽

10.1128/cvi.00583-13 ◽

2013 ◽

Vol 21 (1) ◽

pp. 96-106 ◽

Cited By ~ 18

Author(s):

Lourena E. Costa ◽

Mayara I. S. Lima ◽

Miguel A. Chávez-Fumagalli ◽

Daniel Menezes-Souza ◽

Vivian T. Martins ◽

...

Keyword(s):

Visceral Leishmaniasis ◽

Phage Display ◽

Leishmania Infantum ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Phage Display Technology ◽

Predictive Values ◽

Content Type ◽

Phage Elisa

ABSTRACTVisceral leishmaniasis (VL) is a zoonotic disease that is endemic to Brazil, where dogs are the main domestic parasite reservoirs, and the percentages of infected dogs living in regions where canine VL (CVL) is endemic have ranged from 10% to 62%. Despite technological advances, some problems have been reported with CVL serodiagnosis. The present study describes a sequential subtractive selection through phage display technology from polyclonal antibodies of negative and positive sera that resulted in the identification of potential bacteriophage-fused peptides that were highly sensitive and specific to antibodies of CVL. A negative selection was performed in which phage clones were adhered to purified IgGs from healthy andTrypanosoma cruzi-infected dogs to eliminate cross-reactive phages. The remaining supernatant nonadhered phages were submitted to positive selection against IgG from the blood serum of dogs that were infected withLeishmania infantum. Phage clones that adhered to purified IgGs from the CVL-infected serum samples were selected. Eighteen clones were identified and their reactivities tested by a phage enzyme-linked immunosorbent assay (phage-ELISA) against the serum samples from infected dogs (n= 31) compared to those from vaccinated dogs (n= 21), experimentally infected dogs with cross-reactive parasites (n= 23), and healthy controls (n= 17). Eight clones presented sensitivity, specificity, and positive and negative predictive values of 100%, and they showed no cross-reactivity withT. cruzi- orEhrlichia canis-infected dogs or with dogs vaccinated with two different commercial CVL vaccines in Brazil. Our study identified eight mimotopes ofL. infantumantigens with 100% accuracy for CVL serodiagnosis. The use of these mimotopes by phage-ELISA proved to be an excellent assay that was reproducible, simple, fast, and inexpensive, and it can be applied in CVL-monitoring programs.

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Prospection of immunological biomarkers for characterization and monitoring of asymptomatic Leishmania (Leishmania) infantum infection

Parasitology ◽

10.1017/s0031182020000852 ◽

2020 ◽

Vol 147 (10) ◽

pp. 1124-1132

Author(s):

Gisele Macêdo Rodrigues da Cunha ◽

Mariângela Carneiro ◽

Marcelo Antônio Pascoal-Xavier ◽

Iara Caixeta Marques da Rocha ◽

Fernanda do Carmo Magalhães ◽

...

Keyword(s):

Leishmania Infantum ◽

Regression Tree ◽

Cross Sectional Study ◽

Asymptomatic Infection ◽

Classification And Regression Tree ◽

Soluble Antigen ◽

Serum Samples ◽

Serological Tests ◽

Asymptomatic Group ◽

Cross Sectional

AbstractIn areas endemic for Leishmania infantum, an asymptomatic infection may be an indicator of the extent of transmission. The main goal of this study was to evaluate the applicability of measuring circulating immunological biomarkers as an alternative strategy to characterize and monitor L. infantum asymptomatic infections in combination with serological methods. To this end, 179 children from a region endemic for visceral leishmaniasis (VL), aged 1–10 years old, selected from a cross-sectional study, were identified as asymptomatic (n = 81) or uninfected (n = 98) by qPCR and/or serological tests (ELISA using L. infantum soluble antigen and rK39), and, together with serum samples of children diagnosed with VL (n = 43), were subjected to avidity tests and cytokine levels measurement. Avidity rates (AR) ranging from 41 to 70% were found in 29 children (66%) from the asymptomatic group. On the other hand, high AR (above 70%) were observed in 27 children (64%) from the VL group. Logistic Regression and Classification and Regression Tree (CART) analyses demonstrated that lower AR and IFN-γ production associated with higher IL-17A levels were hallmarks in asymptomatic L. infantum infections. Therefore, this study proposes an association of immunological biomarkers that can be used as a complementary strategy for the characterization and monitoring of asymptomatic VL infections in children living in endemic areas.

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Evaluation of the Serologic Cross-Reactivity between Transmissible Gastroenteritis Coronavirus and Porcine Respiratory Coronavirus Using Commercial Blocking Enzyme-Linked Immunosorbent Assay Kits

mSphere ◽

10.1128/msphere.00017-19 ◽

2019 ◽

Vol 4 (2) ◽

Cited By ~ 4

Author(s):

Ronaldo Magtoto ◽

Korakrit Poonsuk ◽

David Baum ◽

Jianqiang Zhang ◽

Qi Chen ◽

...

Keyword(s):

Culture Medium ◽

Large Deletion ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Transmissible Gastroenteritis Virus ◽

Serum Samples ◽

Serological Tests ◽

Transmissible Gastroenteritis ◽

Respiratory Coronavirus ◽

Porcine Respiratory

ABSTRACTThis study compared the performances of three commercial transmissible gastroenteritis virus/porcine respiratory coronavirus (TGEV/PRCV) blocking enzyme-linked immunosorbent assays (ELISAs) using serum samples (n = 528) collected over a 49-day observation period from pigs inoculated with TGEV strain Purdue (n = 12), TGEV strain Miller (n = 12), PRCV (n= 12), or with virus-free culture medium (n = 12). ELISA results were evaluated both with “suspect” results interpreted as positive and then as negative. All commercial kits showed excellent diagnostic specificity (99 to 100%) when testing samples from pigs inoculated with virus-free culture medium. However, analyses revealed differences between the kits in diagnostic sensitivity (percent TGEV- or PRCV-seropositive pigs), and all kits showed significant (P < 0.05) cross-reactivity between TGEV and PRCV serum antibodies, particularly during early stages of the infections. Serologic cross-reactivity between TGEV and PRCV seemed to be TGEV strain dependent, with a higher percentage of PRCV-false-positive results for pigs inoculated with TGEV Purdue than for TGEV Miller. Moreover, the overall proportion of false positives was higher when suspect results were interpreted as positive, regardless of the ELISA kit evaluated.IMPORTANCECurrent measures to prevent TGEV from entering a naive herd include quarantine and testing for TGEV-seronegative animals. However, TGEV serology is complicated due to the cross-reactivity with PRCV, which circulates subclinically in most swine herds worldwide. Conventional serological tests cannot distinguish between TGEV and PRCV antibodies; however, blocking ELISAs using antigen containing a large deletion in the amino terminus of the PRCV S protein permit differentiation of PRCV and TGEV antibodies. Several commercial TGEV/PRCV blocking ELISAs are available, but performance comparisons have not been reported in recent research. This study demonstrates that the serologic cross-reactivity between TGEV and PRCV affects the accuracy of commercial blocking ELISAs. Individual test results must be interpreted with caution, particularly in the event of suspect results. Therefore, commercial TGEV/PRCV blocking ELISAs should only be applied on a herd basis.

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Human herpes virus 8 antibodies in HIV-positive patients in Surabaya, Indonesia

Infectious Disease Reports ◽

10.4081/idr.2020.8746 ◽

2020 ◽

Author(s):

Devi Oktafiani ◽

Ni Luh Ayu Megasari ◽

Elsa Fitriana ◽

Nasronudin ◽

Maria Inge Lusida ◽

...

Keyword(s):

Drug Users ◽

Sandwich Elisa ◽

Human Herpesvirus ◽

Intravenous Drug ◽

Enzyme Linked Immunosorbent Assay ◽

Hiv Positive ◽

Intravenous Drug Users ◽

Serum Samples ◽

Serological Tests ◽

Human Herpes Virus 8

Background: Human herpesvirus 8 (HHV-8) infection is etiologically related to Kaposi’s sarcoma. Antibodies directed against HHV-8 can be detected in 80%–95% of HIV-seropositive patients with KS. HHV-8 serological tests have been done in several countries in Southeast Asia such as Malaysia, and Thailand however no serological data is available in Indonesia. This study was to examine the presence of HHV-8 antibodies in HIV-positive patients in Surabaya, Indonesia. Material and methods: Ninety-one serum samples were collected from HIV-positive patients in Surabaya, Indonesia. Human immunodeficiency virus-positive serum samples were collected from 10 homosexual men, 25 intravenous drug users (IVDUs) and 56 heterosexuals. Serums were then tested for the presence of HHV-8 antibody by using sandwich ELISA (Abbexa Ltd, Cambridge, UK). Results: The total of 91 HIV-infected were testing with antibodies to HHV-8 using enzyme-linked immunosorbent assay. Antibodies of HHV-8 were detected in 7/91 (7.7%) of the samples. According to a gender, six men (85.7%) and a women (14.3%) were positive of HHV-8 antibodies. No correlation regarding the gender and age from this study. The antibodies of HHV-8 was detected among intravenous drug users (IVDUs) men 5/7 (42.8%) and 2/7 (28.6%) from homosexual and heterosexual, respectively. Conclusion: This study found the presence of HHV-8 antibodies in 7.7% of patients in Surabaya, Indonesia. This finding was higher more than Southeast Asian countries. The patients with a positive result could suggest measures to prevent HHV-8 infection.

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Detection of bluetongue virus antibodies in sheep from Paraná, Brazil

Semina Ciências Agrárias ◽

10.5433/1679-0359.2020v41n3p879 ◽

2020 ◽

Vol 41 (3) ◽

pp. 879

Author(s):

Maria Carolina Ricciardi Sbizera ◽

Luiz Fernando Coelho da Cunha Filho ◽

Michele Lunardi ◽

Simone Fernanda Nedel Pertile ◽

Thais Helena Constantino Patelli ◽

...

Keyword(s):

Bluetongue Virus ◽

Animal Health ◽

Enzyme Linked Immunosorbent Assay ◽

Test Results ◽

Serum Samples ◽

Agar Gel ◽

Serological Tests ◽

High Occurrence ◽

Predominant Factor ◽

World Organization

Bluetongue (BT) is an infectious and non-contagious disease caused by bluetongue virus (BTV) belonging to the genus Orbivirus. It is transmitted by a hematophagous vector, Culicoides sp., to ruminants, particularly to sheep, which are most susceptible to this disease. The main serological tests are agar gel immunodiffusion (AGID), which is recommended by the World Organization for Animal Health (OIE), and the competitive enzyme-linked immunosorbent assay (cELISA), which has the advantage of no cross-reaction with other orbiviruses. The aim was to compare the results of these two tests by conducting them on sera collected from sheep in the state of Paraná, Brazil. From March to October 2017, serum samples were collected from 270 sheep from 10 farms in six mesoregions of Paraná. The samples were subjected to AGID and cELISA to detect antibodies against BTV. Based on the test results, we classified the sheep as low, moderate, and high occurrence. The results demonstrated that 64.81% (175/270) of the sheep were seropositive through the cELISA test, showing a high occurrence, and 41.11% (111/270) were seropositive through the AGID test, indicating a moderate occurrence. The concordance between the tests was moderate (0.51) as determined by the Kappa coefficient. Among the studied farms, 90% (9/10) presented at least one seropositive sheep, and the number of animals tested positive by the cELISA test was higher than those by the AGID test. Favorable climate, which favors the presence and multiplication of the culicoid vector and the occurrence of infection, was the biggest predominant factor responsible for the obtained results. The low occurrence in farms with milder climate suggest that the presence of antibodies also occurs due to the low pathogenicity of circulating serotypes in the different mesoregions studied. It is concluded that BTV infection is present in the sheep herds in Paraná, and the occurrence was moderate detected by AGID test and high detected by cELISA test.

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