scholarly journals Enzyme-Linked Immunosorbent Assay for Recombinant K39 Antigen in Diagnosis and Prognosis of Indian Visceral Leishmaniasis

2001 ◽  
Vol 8 (6) ◽  
pp. 1220-1224 ◽  
Author(s):  
R. Kumar ◽  
K. Pai ◽  
K. Pathak ◽  
S. Sundar

ABSTRACT The recombinant product (rK39) of the 39-amino-acid repeats encoded by a kinesin-like protein-encoding gene of Leishmania chagasi was evaluated by enzyme-linked immunosorbent assay (ELISA) for diagnostic potential and the ability to predict the response to therapy in Indian kala-azar or visceral leishmaniasis (VL); we also compared its performance with that of crude soluble antigen (CSA). At the diagnosis of VL, the anti-rK39 antibody titer was 59-fold higher than the anti-CSA antibody titer. With successful therapy, antibody titers declined steeply at the end of treatment and during follow-up. In contrast, patients who relapsed showed increased titers of antibodies to rK39. The extremely high levels of anti-rK39 antibodies in VL cases suggest the application of rK39 for sensitive and specific serodiagnosis, and rK39 ELISA is also valuable in monitoring drug therapy and detecting relapse of the disease.

Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 744-749 ◽  
Author(s):  
JD Tamerius ◽  
JG Curd ◽  
P Tani ◽  
R McMillan

Abstract The selection of platelet donors for patients who are refractory to random donor platelets often presents a difficult clinical problem. We describe an enzyme-linked immunosorbent assay (ELISA) for evaluating alloantibodies in refractory patients. Platelets from prospective donors are immobilized on microtiter plates and, after incubation with test serum and washing, platelet-bound IgG is detected with enzyme- linked anti-human IgG. Platelets from 46 prospective donors were tested. Twenty-two were judged compatible (reciprocal of the antibody titer less than 16) and, of these, 15 were used as platelet donors; each gave a measurable platelet increment after transfusion. The magnitude of the response was roughly proportional to the assay results. Platelets from donors giving antibody titers less than 4 resulted in platelet increments at 1 hr ranging from 4,890 to 22,200 (median 12,600), while platelets from donors giving titers of 8 or 16 resulted in lesser increments (550–4548). Conversely, 5 of the 24 patients found incompatible by the assay (titer greater than 16) gave no platelet increment, and in 3 instances, the recipient developed fever and chills after the transfusion. The assay is sensitive, simple, and adaptable to the clinical laboratory. Platelets from volunteer donor panels can be plated and stored for up to 6 mo.


2010 ◽  
Vol 18 (2) ◽  
pp. 346-348 ◽  
Author(s):  
Kamlesh Gidwani ◽  
Albert Picado ◽  
Bart Ostyn ◽  
Shri Prakash Singh ◽  
Rajiv Kumar ◽  
...  

ABSTRACTThe persistence of anti-Leishmania donovaniantibodies in past visceral leishmaniasis (VL) cases was retrospectively assessed by means of the direct agglutination test (DAT) and the rK39 enzyme-linked immunosorbent assay (ELISA). Antibody titers remained high for an extended period of time in past cases of VL. These results highlight the need to carefully elicit the history of patients with VL symptoms.


Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 744-749
Author(s):  
JD Tamerius ◽  
JG Curd ◽  
P Tani ◽  
R McMillan

The selection of platelet donors for patients who are refractory to random donor platelets often presents a difficult clinical problem. We describe an enzyme-linked immunosorbent assay (ELISA) for evaluating alloantibodies in refractory patients. Platelets from prospective donors are immobilized on microtiter plates and, after incubation with test serum and washing, platelet-bound IgG is detected with enzyme- linked anti-human IgG. Platelets from 46 prospective donors were tested. Twenty-two were judged compatible (reciprocal of the antibody titer less than 16) and, of these, 15 were used as platelet donors; each gave a measurable platelet increment after transfusion. The magnitude of the response was roughly proportional to the assay results. Platelets from donors giving antibody titers less than 4 resulted in platelet increments at 1 hr ranging from 4,890 to 22,200 (median 12,600), while platelets from donors giving titers of 8 or 16 resulted in lesser increments (550–4548). Conversely, 5 of the 24 patients found incompatible by the assay (titer greater than 16) gave no platelet increment, and in 3 instances, the recipient developed fever and chills after the transfusion. The assay is sensitive, simple, and adaptable to the clinical laboratory. Platelets from volunteer donor panels can be plated and stored for up to 6 mo.


2012 ◽  
Vol 19 (9) ◽  
pp. 1487-1491 ◽  
Author(s):  
Sami Lakhal ◽  
Salima Mekki ◽  
Imène Ben-Abda ◽  
Mohamed Mousli ◽  
Fethi Amri ◽  
...  

ABSTRACTHuman visceral leishmaniasis (VL) is routinely diagnosed by detecting IgG that specifically binds toLeishmaniaantigens. The enzyme-linked immunosorbent assay (ELISA) remains a widely used method. However, the biggest challenge remains the choice of antigen with the highest specificity and sensitivity. This study is aimed at assessing the diagnostic performances of crudeLeishmaniahistone (CLH) protein-based ELISAs in Mediterranean VL patients. The CLH proteins were biochemically purified from promastigote nuclear extracts. Their reactivities were analyzed by Western blotting (WB) using rabbit polyclonal antibodies againstLeishmaniarecombinant histones and sera from VL patients, respectively. Then, the diagnostic potential of CLH proteins was validated by the CLH-based ELISA using 42 infantile VL patients' sera and 70 control subjects. The CLH-based ELISA performance was compared to that of the solubleLeishmaniaantigen (SLA)- and the recombinant K39 (rK39)-based ELISAs. Analysis of the WB profile with the use of polyclonal antibodies confirmed the histone origin of low molecular mass proteins (12 to 16 kDa). All VL samples tested presented antibodies reacting against different antigen fractions; however, recognition patterns were different depending on the reactivity of each serum. CLH-based ELISA showed an excellent ability to discriminate between VL cases and healthy controls (97.6% sensitivity and 100% specificity). It had a diagnostic performance similar to that of rK39-based ELISA (97.6% sensitivity and 97.1% specificity,P= 0.5) and a better serodiagnosis accuracy than the SLA-based ELISA (85.7% sensitivity and 90% specificity,P< 0.05). Therefore, crudeLeishmaniahistone extract could be a valuable antigen for clinical use.


1978 ◽  
Vol 8 (3) ◽  
pp. 268-276
Author(s):  
L H Ghose ◽  
R D Schnagl ◽  
I H Holmes

The development of a micro-scale enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase as the marker enzyme for the detection and measurement of human rotavirus antibodies is described. A semipurified preparation of the serologically related simian agent, SA-11 virus, was used as the antigen. Test sera were reacted with antigen-sensitized wells in disposable poly-vinyl microplates. Any attached antibody was detected by the addition of peroxidase-labeled anti-species immunoglobulin (conjugate) followed by assay of the enzyme reaction with its substrate, hydrogen peroxide plus 5-aminosalicylic acid. This micro-ELISA was compared with complement fixation in a seroepidemiological study of the age prevalence of rotavirus antibody in Aboriginal and European populations living in the same outback area in Australia. The ELISA (results read with the naked eye) proved to be approximately 16 times more sensitive than complement fixation. Of Aborigines, 71% had rotavirus complement-fixing antibody, as compared to 45% of Europeans. By ELISA 100% of both populations had rotavirus antibodies. Mean antibody titers in the different age groups were higher in Aborigines than in Europeans. Antibody levels rose steeply throughout the first 20 years of life, remained high during the next 20 years, then increased again at least up to the age of 60 years. The micro-ELISA was practical, simple to perform, and more suitable than complement fixation for large seroepidemiological rotavirus studies. It also has potential for serodiagnosis of the disease, both in the laboratory and in the field.


2000 ◽  
Vol 12 (2) ◽  
pp. 142-145 ◽  
Author(s):  
James O. Mecham ◽  
Michael M. Jochim

An enzyme-linked immunosorbent assay has been developed to detect antibodies to epizootic hemorrhagic disease of deer virus (EHDV). The assay incorporates a monoclonal antibody to EHDV serotype 2 (EHDV-2) that demonstrates specificity for the viral structural protein, VP7. The assay was evaluated with sequential sera collected from cattle experimentally infected with EHDV serotype 1 (EHDV-1) and EHDV-2, as well as the four serotypes of bluetongue virus (BTV), BTV-10, BTV-11, BTV-13, and BTV-17, that currently circulate in the US. A competitive and a blocking format as well as the use of antigen produced from both EHDV-1-and EHDV-2-infected cells were evaluated. The assay was able to detect specific antibody as early as 7 days after infection and could differentiate animals experimentally infected with EHDV from those experimentally infected with BTV. The diagnostic potential of this assay was demonstrated with field-collected serum samples from cattle, deer, and buffalo.


2008 ◽  
Vol 157 (3-4) ◽  
pp. 175-181 ◽  
Author(s):  
Teresinha Cristina Cândido ◽  
Sílvia Helena Venturoli Perri ◽  
Tatiana de Oliveira Gerzoschkwitz ◽  
Maria Cecília Rui Luvizotto ◽  
Valéria Marçal Felix de Lima

PEDIATRICS ◽  
1984 ◽  
Vol 74 (1) ◽  
pp. 90-93
Author(s):  
M. Dianne Murphy ◽  
Philip A. Brunell ◽  
Alan W. Lievens ◽  
Ziad M. Shehab

A measles epidemic in San Antonio, Texas provided a population of children who were immunized at ≤10 months of age and reimmunized at ≥15 months of age. Of these children, 302 were evaluated for measles antibody by the sensitive enzyme-linked immunosorbent assay (ELISA), and their responses were compared with those of 300 children who had been immunized at the customary time (≥15 months) with a single immunization. There were only five seronegative findings in each group. The children immunized at the customary time did have significantly higher (P &lt; .001) antibody titers than the children immunized at ≤10 months and reimmunized at ≥15 months. These results indicate that early immunization followed by reimmunization may be indicated when young infants are at significant risk of measles exposure. This approach should not create an increased number of serologically nonresponsive children when reimmunized at ≥15 months.


2001 ◽  
Vol 8 (2) ◽  
pp. 266-272 ◽  
Author(s):  
Nelydia F. Concepcion ◽  
Carl E. Frasch

ABSTRACT The specificity of the immune response to the 23-valent pneumococcal-polysaccharide (PS) vaccine in healthy adults and to a pneumococcal conjugate vaccine in infants was examined by measuring immunoglobulin G (IgG) antibody titers by enzyme-linked immunosorbent assay (ELISA) and the opsonophagocytosis assay. ELISA measures total antipneumococcal IgG titers including the titers of functional and nonfunctional antibodies, while the opsonophagocytosis assay measures only functional-antibody titers. Twenty-four pairs of pre- and post-pneumococcal vaccination sera from adults were evaluated (ELISA) for levels of IgG antibodies against serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F. Twelve of the pairs were also examined (opsonophagocytosis assay) for their functional activities. The correlation coefficients between assay results for most types ranged from 0.75 to 0.90, but the correlation coefficient was only about 0.6 for serotypes 4 and 19F. The specificities of these antibodies were further examined by the use of competitive ELISA inhibition. A number of heterologous polysaccharides (types 11A, 12F, 15B, 22F, and 33A) were used as inhibitors. Most of the sera tested showed cross-reacting antibodies, in addition to those removed by pneumococcal C PS absorption. Our data suggest the presence of a common epitope that is found on most pneumococcal PS but that is not absorbed by purified C PS. Use of a heterologous pneumococcal PS (22F) to adsorb the antibodies to the common epitope increased the correlation between the IgG ELISA results and the opsonophagocytosis assay results. The correlation coefficient improve from 0.66 to 0.92 for type 4 and from 0.63 to 0.80 for type 19F. These common-epitope antibodies were largely absent in infants at 7 months of age, suggesting the carbohydrate nature of the epitope.


Sign in / Sign up

Export Citation Format

Share Document