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The manual system, based on our experience, has some advantages

such as it consumes less time in preparation, less expensive, and less

complicated when compared to the other two systems.

For making a tissue microarray block, it is required to follow

the following steps:

1. Place the “donor” block on a flat table and hold the needle
   perpendicular to the marked position of the “donor” block.


2. Insert the needle into the “donor” block at the proper depth
   of 5 mm slowly. Do not insert it quickly or too deep to prevent
   from damaging the “donor” block (see Note 3) (Fig. 1b).


3. Pull out the inner needle so that the tissue is sucked into the
   empty cylinder of the needle (Fig. 1c).


4. If “donor” block is broken, incubate the easily breaking
   “donor” block in a heating oven or at a room temperature of
   37–40 °C for 15–20 min.


5. Place the “recipient” block on a table. Hold the needle with
   the extracted tissue perpendicular to the corresponding holes
   of the “recipient” block.


6. Inject the removed tissue (core) from the “donor” block into
   the corresponding holes of the “recipient” block at the proper
   depth of 4 mm by pushing the plunger slowly (Fig. 1d).


7. Gently push or tap in all tissue cores to ensure evenness for
   microtome.


8. Repeat the steps for every sample.

The semi-automated technique is a computer-assisted TMA platform

and designed to provide users for the construction of microarrays and

sample picking for further nucleic acids extraction and protein isola-

tion. The machine could be connected to: the stage controller, the

stage joystick; the digital camera and the personal computer with

software installed (Fig. 2a). The joystick could be used to control the

movement of needles in different directions manually.

The stage controller enables the stage movement either with a

joystick or under PC program. Besides, it takes care of the needle

head vertical and rotational movement. The high-resolution digital

camera is mounted on the machine stand to capture the image of

the blocks. The zooming is manual. The camera can manually be

rotated around its axis. The motorized stage mounting the modu-

lar sample holder is computer assisted. It ensures precise position-

ing of the specimens under the appropriate needle in the operating

conditions. In the standard configuration, up to nine standard his-

tological cassettes can be horizontally mounted in the block holder.

The needles for punching and transfer are easily clamped to their

holder (Fig. 2b). During operation, the selection of the correct

needle is automated and computer controlled. The programmable

vertical displacement allows a precise “donor” core insertion into

3.1 Manual Method
for Making TMA

3.2 Semi-Automated
Method for Making
TMA

TMA and Esophageal Adenocarcinoma