Understanding the Process of Immunohistochemistry (IHC) Testing in Medical Labs

Summary

• Immunohistochemistry (IHC) is a crucial test used in medical labs to detect protein expression in tissue samples.
• The process for preparing and staining tissue samples for IHC testing involves several steps, including fixation, embedding, sectioning, and staining.
• Proper technique and attention to detail are essential to ensure accurate and reliable results in IHC testing.

Introduction

Immunohistochemistry (IHC) is a widely used technique in medical laboratories to detect protein expression in tissue samples. This testing method allows healthcare professionals to visualize the localization and distribution of specific proteins within tissue specimens, aiding in the diagnosis and treatment of various diseases. In this article, we will explore the intricate process of preparing and staining tissue samples for IHC testing in a medical lab setting in the United States.

Fixation of Tissue Samples

Before staining tissue samples for IHC testing, it is crucial to properly fix the specimens to preserve their structural integrity and protein content. The fixation process involves the following steps:

1. Collection of tissue samples
2. Immersing the samples in fixative solution
3. Allowing the samples to fix for a specific duration

Embedding and Sectioning

Once the tissue samples are fixed, they need to be embedded in a solid medium, such as paraffin wax, to facilitate sectioning. The embedding and sectioning process includes the following steps:

1. Dehydration of fixed tissue samples
2. Clearing the samples in a clearing agent
3. Embedding the samples in paraffin wax blocks
4. Sectioning the embedded samples into thin slices using a microtome

Staining of Tissue Samples

Staining tissue samples is a critical step in the IHC testing process, as it allows for the visualization of specific proteins within the specimens. The staining process typically involves the following steps:

1. Deparaffinization of tissue sections
2. Rehydration of tissues in a series of alcohol baths
3. Antigen retrieval using heat-induced techniques
4. Blocking non-specific binding sites
5. Incubating the tissue sections with primary antibodies
6. Detecting the primary antibodies with secondary antibodies
7. Visualizing the antibody-antigen complexes using a chromogen
8. Counterstaining with hematoxylin
9. Dehydration and mounting of stained tissue sections

Quality Control and Validation

After staining tissue samples for IHC testing, it is essential to perform Quality Control measures to ensure the accuracy and reliability of the results. Quality Control and validation steps include:

1. Reviewing staining patterns under a microscope
2. Comparison of staining results with known positive and negative controls
3. Assessing the intensity and distribution of staining
4. Documenting and recording staining results

Conclusion

Preparing and staining tissue samples for immunohistochemistry (IHC) testing in a medical lab setting is a meticulous process that requires attention to detail and adherence to specific protocols. By following the outlined steps for fixation, embedding, sectioning, and staining, healthcare professionals can obtain accurate and reliable results in IHC testing, aiding in the diagnosis and treatment of various diseases.

Disclaimer: The content provided on this blog is for informational purposes only, reflecting the personal opinions and insights of the author(s) on the topics. The information provided should not be used for diagnosing or treating a health problem or disease, and those seeking personal medical advice should consult with a licensed physician. Always seek the advice of your doctor or other qualified health provider regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. If you think you may have a medical emergency, call 911 or go to the nearest emergency room immediately. No physician-patient relationship is created by this web site or its use. No contributors to this web site make any representations, express or implied, with respect to the information provided herein or to its use. While we strive to share accurate and up-to-date information, we cannot guarantee the completeness, reliability, or accuracy of the content. The blog may also include links to external websites and resources for the convenience of our readers. Please note that linking to other sites does not imply endorsement of their content, practices, or services by us. Readers should use their discretion and judgment while exploring any external links and resources mentioned on this blog.

Related Videos