Immunohistochemistry Quality Control Research Articles

HLA expression and cancer – 14th IHIWS immunohistochemistry quality control exercise exchange results

An immunohistochemistry (IH) quality control exercise was conducted as part of the 14th International HLA (human leukocyte antigen) and Immunogenetics Workshop (IHIWS) HLA Expression and Cancer component. Six laboratories participated and the exercises involved performing IH using three monoclonal antibodies (HC-10, beta2m and SI00) on three sequential paraffin-embedded melanoma sections provided by one laboratory. High-resolution digital photographs of five IH-stained sections were also distributed for interpretation. While there was generally good agreement between laboratories, several differences in staining and interpretation of IH sections were identified and possible reasons given. Interpretation of the high-resolution digital photographs showed a high level of concordance between laboratories. It is suggested that further exercises are conducted as part of future collaborative activities in order to further characterise areas of variability between IH performance and interpretation of results.

Heat-induced Antigen Retrieval: What Are We Retrieving?

Of all molecular aspects lost and recovered during formalin fixation and antigen retrieval, respectively, electrostatic charges have probably received the least attention. This review will focus on our work during the past 7 years. It strongly supports the tenet that electrostatic charges, i.e., net negative on antigens and net positive on antibodies, play an important part in immune reactions and therefore should be given greater attention when focusing on quality control in immunohistochemistry.

Tissue microarrays: applications in genomic research

The widespread application of tissue microarrays in cancer research and the clinical pathology laboratory demonstrates a versatile and portable technology. The rapid integration of tissue microarrays into biomarker discovery and validation processes reflects the forward thinking of researchers who have pioneered the high-density tissue microarray. The precise arrangement of hundreds of archival clinical tissue samples into a composite tissue microarray block is now a proven method for the efficient and standardized analysis of molecular markers. With applications in cancer research, tissue microarrays are a valuable tool in validating candidate markers discovered in highly sensitive genome-wide microarray experiments. With applications in clinical pathology, tissue microarrays are used widely in immunohistochemistry quality control and quality assurance. The timeline of a biomarker implicated in prostate neoplasia, which was identified by complementary DNA expression profiling, validated by tissue microarrays and is now used as a prognostic immunohistochemistry marker, is reviewed. The tissue microarray format provides opportunities for digital imaging acquisition, image processing and database integration. Advances in digital imaging help to alleviate previous bottlenecks in the research pipeline, permit computer image scoring and convey telepathology opportunities for remote image analysis. The tissue microarray industry now includes public and private sectors with varying degrees of research utility and offers a range of potential tissue microarray applications in basic research, prognostic oncology and drug discovery.

Tissue Microarrays for Screening and Quality Control in Immunohistochemistry: Advantage and Disadvantage Compared with Conventional Sausage Blocks

Multitissue (sausage) blocks are used routinely in many diagnostic immunopathology laboratories as quality control and as a tool for screening of the new antibodies. More recently, tissue microarray has been introduced and its utility for high-throughout expression profiling of tumors is well documented. In this study, we investigated the potential utility of this technology as a tool for quality control in routine immunohistochemistry. Because the tissue microarray represent many tissue types with a wide range of antigenic expressions, we find that the tissue microarray technology has the potential to be widely used by diagnostic immunopathology laboratories for quality controls as well as for screening of the sensitivity and specificity of the newly introduced antibodies. (The J Histotechnol 27:95, 2004) Submitted: September 10, 2003; accepted with revisions: March 24, 200

Multitissue Blocks for Quality Control in Immunohistochemistry

A simple method for preparing multitissue control blocks (MTCB) for immunohistochemistry is described. Parallel rectangular tissue sections are embedded in paraffin and sections cut from these blocks are mounted at one end of the glass slide. A section from the tissue to be stained is mounted at the other end of the same glass slide. The slide containing both the control and test sections is processed for immunohistochemistry, allowing both the tissue sample and the controls to be treated equally in all steps. The control blocks can be tailored to include different tissues or tissues fixed in different fixatives, according to the needs of the laboratory. In contrast to MTCBs that contain large numbers of sections, ours provides adequate tissue for each positive control and at the same time allows improved accuracy and diagnostic sensitivity. MTCBs can be used as general control blocks for the majority of routine immunohistochemical stains and for initial antibody screening. (The J Histotechnol 18:127, 1995)

Multitissue Blocks for Quality Control in Immunohistochemistry

A simple method for preparing multitissue control blocks (MTCB) for immunohistochemistry is described. Parallel rectangular tissue sections are embedded in paraffin and sections cut from these blocks are mounted at one end of the glass slide. A section from the tissue to be stained is mounted at the other end of the same glass slide. The slide containing both the control and test sections is processed for immunohistochemistry, allowing both the tissue sample and the controls to be treated equally in all steps. The control blocks can be tailored to include different tissues or tissues fixed in different fixatives, according to the needs of the laboratory. In contrast to MTCBs that contain large numbers of sections, ours provides adequate tissue for each positive control and at the same time allows improved accuracy and diagnostic sensitivity. MTCBs can be used as general control blocks for the majority of routine immunohistochemical stains and for initial antibody screening. (The J Histotechnol 18:127, 1995)

Quality assurance and standardization in immunohistochemistry. A proposal for the annual meeting of the Biological Stain Commission, June, 1991.

Quality assurance, quality control, proficiency testing, reagent documentation and validation are standard parts of everyday practice in clinical laboratories throughout the United States. Immunohistochemical stains employ reagents and principles in common with immunoenzyme methods utilized in the clinical laboratory. However, immunohistochemistry has not routinely been subjected to similar standardization and quality assurance procedures that manufacturers and pathologists alike have applied to essentially the same techniques in the clinical laboratory environment. The current proposal was invited by the Biological Stain Commission with the charge of incorporating the findings of previous workshops on quality control in immunohistochemistry into a practical design for implementation. The status of quality assurance, quality control and standardization in immunohistochemistry is reviewed and a phased strategy for implementation is proposed.

Special Report: Quality Control in Immunohistochemistry: Report of a Workshop Sponsored by the Biological Stain Commission

Although immunohistochemical methods are increasingly applied in diagnostic histopathology, there has been little standardization or quality control of immunoreagents; and published reports have not standardized Material and Methods for meaningful comparisons of results among clinicians. The Biological Stain Commission-sponsored workshop was convened to address the following issues: a manufacturers' testing program for probity of commercial antibodies, development of a manual for performance criteria and quality control assurance procedures, standardization of package inserts, standardization of information provided in the Materials and Methods sections of publications, establishment of a reagent and procedure clearing house, study of the effects of different fixation regimes on tissue antigens, and investigation of the environmental conditions needed for antigen-antibody interaction. The recommendations of the ad hoc committee and their implications for the future are discussed.