Research Techniques Made Simple:Tissue Microarray

Kathleen Barrette1, Joost J. van den Oord2, Marjan Garmyn1

1. Laboratory of Dermatology, Department of Oncology, KU Leuven, Leuven, Belgium2. Translational Cell & Tissue Research, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium

History of TMA

• 1986: first description of TMA • Wan WH, Fortuna MB, Furmanski P: A rapid and efficient method for testing immunohistochemical

reactivity of monoclonal antibodies against multiple tissue samples simultaneously. J Immunol Methods 103:121-129 (1987).

• 1998: first development of a device which could rapidly and reproducibly produce TMAs

• Kononen J, Bubendorf L, Kallioniemi A, Barlund M, Schraml P, Leighton S, Torhorst J, Mihatsch MJ, Sauter G, Kallioniemi OP: Tissue microarrays for high-throughput molecular profiling of tumor specimens. Nat Med 4:844-847 (1998).

TMA construction

1. Delineate area of interest

- Paraffin block cut on a microtome-Stained with hematoxylin & eosin-Area of interest is delineated

TMA construction

2. The cylindrical core

- Needle is placed above area of interest

- Punch out the core by moving the needle down and up into the original donor block

- Tissue core is situated in the hollow needle

TMA construction

3. The recipient block

- Core is placed in an empty, predrilled recipient block

- Down movement of needle and upper part of the needle to push out the core

TMA construction

4. The new TMA glass slide

- Recipient block is heated to 37°C to fix cores

- Block is cut on a microtome and mounted on a glass slide

- Slides can be stained with hematoxylin & eosin, immunohistochemistry or other applications

Applications of a TMA

• To screen tissue samples from a large patient cohort– for the expression of a specific protein, via

immunohistochemistry– for the presence or absence of a specific gene

sequence via fluorescence in situ hybridization (FISH)

Advantages of TMA• Simultaneous analysis of a large number of

specimens– Multiple cores from multiple donor blocks

• Construction of in vivo tumor progression model– Easy to include different tumor progression stadia

• Experimental uniformity– Each tissue core is treated in an identical manner

(same antigen retrieval, temperature, incubation time, washing procedure, and reagent concentration)

• Decreased volume, time, and cost

Limitations of TMA

• Less suited for heterogeneous tissues– Just one core was selected from whole paraffin block– Take multiple cores from one block if tissue is

heterogeneous• Expensive– Commercial TMA builder is expensive– Constructing a TMA without a commercial TMA

builder is possible but time-consuming• Variations in antigenicity– Variations in antigenicity of stored archival samples