Comparison of rSP03B-ELISA and rSP03B sero-strip with standard SGH-ELISA.

<p>Comparison of rSP03B-ELISA and rSP03B sero-strip with standard SGH-ELISA.</p

Composition of the rSP03B sero-strip.

<p>The rSP03B sero-strip consists of a backing card to which a lower absorbent and an upper absorbent pad are attached. Both of these pads overlap an NC membrane located in the middle of the test. On the NC membrane 3 lines are coated: the sample line, a test line and a control line. The lower absorbent pad is impregnated with a colloidal gold-conjugate (conjugate pad), consisting of a mixture of the conjugates for the test and the control line. NC = nitrocellulose.</p

Interpretation of the results.

<p>The test is only valid if the migration control line is present (A and B). A positive test result is observed when two lines (test and control) are visible on the NC membrane (A). The test is considered negative when only the control line is present (B). When the migration control line is not present, the test is considered invalid and should be redone (C and D). NC, Nitrocellulose.</p

Sensitivity and specificity of each serological method (SGH-ELISA, rSP03B-ELISA and the rSP03B sero-strip).

<p>Sensitivity and specificity of each serological method (SGH-ELISA, rSP03B-ELISA and the rSP03B sero-strip).</p

Intensity of test line relates to amount of target Ab deposited.

<p>Dilution series of four highly positive sera samples indicate that the intensity of the purple color at the test line decreases when a lower amount of target Ab is deposited on the strip. The sample appears negative when a dilution of 1/50 is used. A: undiluted sample; B: 1/10 sample dilution; C: 1/20 sample dilution; D: 1/30 sample dilution; E: 1/40 sample dilution; F: 1/50 sample dilution.</p

Stepwise description of the rSP03B sero-strip principle.

<p>To start the test a buffer is deposited on the sample line (NC membrane) (1). Immediately after applying the buffer, the sample is spotted on the same position (2). Both the buffer and the sample will migrate to the upper part of the strip. The anti-rSP03B Abs present in the sample get captured by the rSP03B Ag coated on the test line (3). The strip is then immediately dipped into the migration buffer solution (4). After which the colloidal gold conjugate mixture gets hydrated and starts migrating upwards together with the moving liquid (5). The anti-dog IgG Ab-gold conjugate binds to the dog IgG Abs on the test line. The colloidal gold control conjugate is captured by the GAC Abs present at the control line (6). NC, Nitrocellulose; Abs, Antibodies; Ag, Antigen; GAC, Goat anti-chicken.</p

Specific IgG1 ELISA levels were high in active and relapsed VL but negative or substantially decreased in cured VL using unpaired serum samples.

<p>[A] Indian VL pilot study (Trial 1). [B] Indian VL expanded study (Trial 2). [C] Sudanese VL. Mean and 95% CI are shown for each data set (solid black lines); note the different Y axis scales. In each study set, the means plus three standard deviations obtained using DAT-seronegative endemic healthy control (EHC) samples was used to calculate the cut-off value (dotted line) and p values of<0.05 were considered significant.</p

Single (unpaired) samples used in IgG subclass comparisons, and clinical status of the Indian and Sudanese patient groups.

<p>EHC = endemic healthy control; PKDL = post kala-azar dermal leishmaniasis.</p>a<p>treated, not in recent past, but time of treatment unknown.</p><p>Single (unpaired) samples used in IgG subclass comparisons, and clinical status of the Indian and Sudanese patient groups.</p

Summary of results from IgG1 rapid diagnostic tests (RDT) prototypes.

a<p>Therapy: sodium antimony gluconate n = 8; miltefosine n = 10; amphotericin B n = 3; combination therapy n = 2.</p>b<p>22 of these samples were also used with prototype 1.</p>c<p>these samples were also negative with prototype 1.</p>d<p>these 5 samples were also used with prototype 1.</p>e<p>malaria n = 3; hepatitis n = 1; TB n = 2; dengue n = 1.</p><p>Summary of results from IgG1 rapid diagnostic tests (RDT) prototypes.</p

IgG subclass serology in VL and PKDL: Published studies.

<p>IgG subclass serology in VL and PKDL: Published studies.</p