Question

Discuss briefly the process of Indirect ELISA.

Answer 1

Hint: Indirect ELISA involves the two-binding process of the antibodies. In this process the primary and the secondary antibody are joined by this binding process. This method is used to detect the disease by using the interaction between the antigens and the antibodies.

Complete Answer:
In the first binding process of ELISA, the primary antibody is incubated with the antigen coated wells. After that in the second process, the primary antibody is incubated with the secondary antibody. But this also results in the nonspecific signals due to the cross reaction of the labelled secondary antibody. The result of this method is used to find the disease by the change in the color of the sample obtained.

The steps involved in indirect ELISA:
(1) The incubation is done on the micro-well plates with the antigens, after that it is washed up and blocked with BSA.
(2) The primary antibody samples are added to the micro well plates that are well coated with the antigens and after the incubation is completed it is washed.
(3) Enzyme linked secondary antibodies are added to the primary antibody and washed to obtain the pure samples.
(4) A substrate containing the antibody is added and then the enzymes on the antibody show the indication for the presence of the antibodies. If no antibodies are present, then it will not show any indications on the micro-well plates.

Note: This method of indirect ELISA is used to measure the amount or the quantity of the antibodies or the proteins present in the serum or the other body fluids. This is identified by the change in the color and the composition of the sample.