Hello Kaled Nather Taha

It won’t be proper to make comparisons between techniques in medical research. Each technique has its own importance. In medical research different techniques are used whenever the situation demands. The information provided by any technique, may it be immunoassays (serum) or IHC is unique and gives valuable information in that particular area of research.

Immunohistochemistry (IHC) determines the tissue distribution of an antigen of interest in health and disease. The immunohistochemical reactions can be used in different situations like histogenetic diagnosis of morphologically non-differentiated neoplasia, subtyping of neoplasia (like lymphomas), characterization of primary site of malignant neoplasia, research for prognostic factors and therapeutic indications of some diseases, discrimination of benign versus the malign nature of certain cell and so on.

In IHC there are certain aspects as you mentioned which needs to be taken care of. Handling, fixation, specimen delivery to the laboratory and antigen retrieval are all critical factors. The use of detection systems (secondary antibodies) is also considered valuable in error reduction. The selection of antibody panels is one of the most important aspects for optimal applicability of immunohistochemistry. Regarding the validation of findings and their interpretation, it is necessary to observe the reactivity patterns of the negative and positive, internal, and external controls.

Every technique has its own merits and demerits. For serum study if for instance you use ELISA, it too has disadvantages like, 1) high possibility of false positivity/negativity. 2) insufficient blocking resulting in false positive results, 3) the secondary antibody could increase the risk of cross-reactivity and potential cross-reactivity could cause high background noise, 4) well-to-well variation.

Best.

Malcolm Nobre thanks for your answer

IHC and serum marker analysis are two different techniques used in clinical research for different purposes. For example, cellular localization of any antigen can not be carried out by serum analysis by any existing methods such as ELISA, Spectrophotometry, Gel Electrophoresis etc.

Thus, comparsion of two techniques may not be appropriate as both have their own importance for perticular analysis in clinical research.

Best

Shail K Chaube thanks for your answer...

I need the comparison from the viewpoint of the researcher trying to study the biomarker?

so the comparison is important in this situation...

by comparing the applicability of this marker to become a diagnostic test in future ....? i waiting for your comment

As I have replied above, both techniques have their own importance in diagnostic field. But after considering your concern as you have mentioned, I would suggest as a researcher if you are trying to develop a biomarker (although both are invasive methods), go ahead and try for the development of serum biomarker for the following (but not limited to) reasons.

1. Comparatively easy to collect, handle, store and process the blood samples

2. No sophisticated lab conditions and surgical wares are required for blood serum (as usually done for biopsy samples).

3. For sample collection, no specific surgeon is required and even technician can collect the blood sample from the patients

4. Comparatively, blood serum contains large number of analytes (for most of the diseases) that gives wide options to develop biomarkers for diagnostic use.

5. Large number of samples could be handled in a micro plate system (ELISA) and other methods like Electrophoresis, Western Blotting etc. in order to provide quick, reliable and accurate results.

6. Many more .....

However, by saying this, I do not underestimate the importance of IHC as it is a good method to develop a cellular biomarkers. As you know that the Histology, Histochemistry, Immunohistochemistry (IHC), Immunocytochemistry (ICC) etc. are very common for tumor/cancer diagnostics etc.

Best