Question

IMMUNOLOGY ELISA INTERPRETATION

in a ELISA assay If a couple of samples give you values below the lowest standard, two within the range of the standards, and the rest above the highest standard, how would you interpret those results with the knowledge that the minimum detectable dose of HIV gp120 is approximately 46.88 pg/ml.

Answer 1

1. ELISA is an enzyme-linked immunosorbent assay that is used to detect the virus.

2. We have provided the minimum detectable dose of HIV gp120 is approximately 46.88 pg/ml which we are going to use this to decide the standard.

how to calculate the standard -

here we are given the minimum detectable dose 46.88 pg/ml

If we take twice the minimum dose i.e. multiplied by 2 (purely considered it is not the exact fig.) it becomes 46.88 x 2 = 93.76 pg/ml which is considered as possible standard value.

3. A first condition where is provided with the samples which show the value bellow the lowest standard - In this case, if we observed the titer of virus in ELISA is below the lowest standard means the sample is negative for the HIV gp120 i.e. there is no infection.

(Note- bellow lowest standard is the value calculated by considering the lowest possible titer.)

4. Second condition two samples are provided which are in the range of the standard. - In this case, the provided samples are positive because the titer is in the range of standard value of positive samples. But in this case, reconfirmation is needed.

5. In the third condition, we have been provided with the samples which are above the highest standard which means the titer in above the standard. samples are positive for HIV gp120.