Question

1. Describe three ways that an immunofluorescence assay is similar to an ELISA that would test for specific antibodies.

Answer 1

the three ways are:

1. immunofluroscent assay(IFA)I is a microscopic technique mostly used for microbial samples. the technique use specific antibodies that binds to antigen which results in glowing of fluroscent dye due to specific binding of Ag-Ab within the cell. ELISA is an enzymatic asssay mostly used in pathogical and biotechnological works. here also specific antibodies(Ab) are used that bind to the protein (antigen Ag) to be measured.

2. In IFA the Ab recognises the Ag (epitope). as there might be many antibodies that can bind to antigen but the level of binding of Ab to Ag vary and there is a flurophore that bind to the Ab resulting in positive results. In ELISA Ab attaches to the surface where specific Ag  and those Ab are linked to an ENzyme and when the substrate is added then it result in colouration showing positive same as that occur in IFA.

3. In IFA the method for detection are similar as that of different types of ELISA eg; in IFA when an antibody with a flurophore bind to its specific epitope and when watched under microscope it confirm the presence of antigen like the same way direct ELISA does. In direct ELISA when primary antibody with an enzyme binds to the antigen that is specific and on addition of substrate it shows colouration.Again, secondary immunofluroscence is similar to competitive ELISA i.e. when the primary antibody binds to sprcific antigen then secondary antibody comes and binds to the prmary antibody which is attach to the antigen allowing more flurophore tagged antibodies to attach to the target leading to increase fluroscent signal in the microscope which is similar to competitive ELISA as in competitive ELISA when the peimary Ab binds to a specific Ag after that comes the secondary Ab which is attach to an enzyyme and this secondary Ab binds to the primary Ab and when there is addition of substrate showing a Fluroscent or chromogenic signal