Aug 13, 2020
Enzyme linked immunosorbent assay for investigating the binding of Streptococcal Protein-G (SpG) to diverse immunoglobulins
- 1University of the West Indies St. Augustine
- University of the West Indies
- angel.vaillant@sta.uwi.edu
Protocol Citation: Angel A Justiz-Vaillant 2020. Enzyme linked immunosorbent assay for investigating the binding of Streptococcal Protein-G (SpG) to diverse immunoglobulins. protocols.io https://dx.doi.org/10.17504/protocols.io.bjphkmj6
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: August 13, 2020
Last Modified: August 13, 2020
Protocol Integer ID: 40393
Abstract
This SpL ELISA can be used to detect specific antibodies in various animal species including human, mouse, rat, dog, rabbit, chicken, monkey, pig and hamster [1].
1. De Chateau M, Nilson BH, Erntell M, Myhre E, Magnusson CG, Akerstrom B et al. On the interaction between protein L and immunoglobulins of various mammalian species. Scand J Immunol 1993; 37: 399−405
This ELISA is used to study the interaction of Streptococcal protein G with different immunoglobulin preparations.
The 96 well microtitre plate is coated overnight at 4°C with 1 µl/mg per well of Streptococcal protein-G (SpG) in carbonate-bicarbonate buffer pH 9.6.
Then plate is treated with bovine serum albumin solution and washed 4X with PBS-Tween.
50 µl of animal serum (1 mg/ml) is added and incubated for 1h at room temperature and the microplate is rewashed 4X with PBS-Tween.
Then 50 µl of peroxidase-labeled SpG conjugate diluted 1:5000 in PBS-non-fat milk is added to each well and incubated for 1h at RT. The plate is washed 4X with PBS-Tween.
50 µl of 4 mg/ml o-phenylenediamine solution (OPD) is added and the plate is incubated 15 minutes at RT in the dark.
The reaction is stopped with 50 µl of 3M H2SO4 solution.
The plate is visually assessed for the development of colour and read in a microplate reader at 492 nm.
A cut-off point should be calculated as the mean of the optical density of negative controls x 3. The higher the OD value the higher the affinity of SpG to immunoglobulin G.