III.1. Sistema gráfico
III.1.1. Aplicaciones de uso corporativo
For a few stains, it was not possible to directly import the reagents as described for the manual procedure onto the artisantM
platform. One of these related to the Warthin-starry stain. the conventional protocol calls for preparing a gelatin solution in water at a temperature high enough to dissolve the solid gelatin. it is believed that gelatin serves a role in these stains that is somewhat similar to its role in black and white photography. namely, it is believed that gelatin serves as a protective colloid. a common protocol in the conventional manual recipe is to dissolve the (solid) gelatin in water at 56°c for 15 minutes. the dissolved gelatin can then be mixed with a silver nitrate solution and hydroquinone, to form a developer solution for the Warthin-starry stain. the problem we had to solve is that we could not provide a 5% gelatin solution in water as a liquid reagent. at room temperature, the gelatin “gels”, making it impossible to dispense.
a staff colleague, dr. adrian leek, solved the problem by replacing conventional gelatin with a solution of non-gelling gelatin, also sometimes referred to as “partially hydrolyzed gelatin”. non-gelling gelatin is hydrolyzed animal protein derived from collagen. it is produced from enzymatically modified gelatin. it has an approximate molecular weight of about 3,000 daltons and an amino acid profile that is approximately the same as that of gelatin. Unlike gelatin, non-gelling gelatin is soluble at room temperature. after some experimentation, we found that non-gelling gelatin produces an excellent Warthin-starry stain. a patent was awarded for this innovation (U.s. patent 6,465,207).
Conclusion
there were many more challenges and innovative solutions required to make the artisantM than could reasonably be discussed in this short article. the authors are gratified to see the result of their efforts, and the efforts of many talented individuals at cytologix and at dako, in making the artisantM the premier special stains instrument. From its once humble beginnings, it now has a worldwide presence, helping clinical histopathology laboratories stain patient tissue samples all over the globe.The Evolution of the Artisan
™Special Stains Instrument
Chapter 30 Tissue Microarray Technology as a New Approach
for Quality Control with ArtisanLink
Christiane Kahnt, Hanin El-Sayed and Herman Herbst, MD, FRCPath
special stains is an established technique in many pathology laboratories and institutes. Quality control for special stains is one of the major problems in daily practice. even when the protocols are standardized using automated instruments such as the
ArtisanlinktM , there is still a lot of variability left in inter-laboratory results. this is where tissue microarrays (tMa) become helpful when used as a method for quality control and in the facilitation of standardizing different staining procedures such as special stains (also see appendix, page 285). the detection of cellular and tissue structures or microorganisms by special stains is quite common and is often verified by qualitative or quantitative controls. the detection of bacteria, for instance by Ziehl- neelsen stain or silver impregnation techniques such as Warthin- starry or Grocott staining requires a control that definitely contains the characteristic microorganism(s) to be detected in the patient sample. in case of macromolecules, such as interstitial collagens or reticulin fibers, it is necessary to demonstrate characteristic staining patterns in a semi-quantitative approach to control a certain level of staining intensity. Usually such controls are performed on additional or separate slides. this implies that the result of the control stain documented on a separate slide requires extensive documentation and archiving in order to associate the special stain of a patient’s tissue sample with the corresponding control slide. this issue can be avoided using tMa technology (For details about tMa technology, refer to the articles 1, 2 and 3; see references.) the tMa method not only enables a high throughput method of analysis of special stains sample, but also provides an economical alternative to conventional controls on separate slides in immuno- histochemistry (iHc) and in-situ hybridization techniques. the design of the tMa is so much different from the outlines of the patient tissue section, that an accidental mix up between tMa control and patient tissue is unlikely. in addition, no parallel slides are required for documentation as the tMa slide containing the patient sample has all the required material for staining and control. all of this makes the tMa technique a comfortable alternative in the daily routine work.
Tissue Microarray Technology as a New Approach for Quality Control with ArtisanLink
Tissue Microarray Technology as a New Approach for Quality Control with ArtisanLink
an example of “Warthin starry” staining is shown below to demon- strate how tMa can be used as positive and negative controls in the same slide as a patient sample.
Staining Kit Dako Code No. Clinical Application Control Tissue Typical Laboratory Performing the Stain Artisan™ Acid-Fast Bacillius
Stain Kit
AR162 Most commonly used to demonstrate Mycobacterium
tuberculosis in human tissue
Lung,
Mycobacteria (e.g., MAI) Liver AFB+
Microbiology
Artisan™ Gram Stain Kit AR175 Used in identifying Gram-negative bacteria in human tissue
Tissue containing Gram-positive or -negative bacteria
Microbiology or reference laboratory
Artisan™ Warthing-Starry Stain Kit
AR181 Silver method used in the identification of Helicobacter
pylori in human tissues, H. pylori has been associated
with chronic gastritis and ulceration of the stomach
Spirochetes or H. pylori, Gastrointestinal tissue
Microbiology or reference laboratory
Artisan™ Alcian Blue/PAS Stain Kit
AR169 Used as an aid in distinguishing adenocarcinoma from certain sarcomas
Liver, S.I., Colon, Kidney Gastrointestinal laboratory
Artisan™ Reticulin/Nuclear Fast Red Stain Kit
AR179 Used to outline the architecture in liver, spleen, bone marrow, and may be used to highlight the growth pattern of neoplasms
Liver Renal pathology laboratory
Liver laboratory
Artisan™ Gomori's Trichrome Stain Kit
AR167 May be used to differentiate normal structures and injured tissue as in chronic active hepatitis of liver cirrhosis
Normal or Zirrhotic Liver Renal pathology laboratory Liver laboratory
Artisan™ Elastic Stain Kit AR163 Use to demonstrate atrophy of elastic tissue in cases of emphysema, and the loss of elastin fibers in arteriosclerosis, differentiates collagen from elastic
Lung, Artery Cardiovascular laboratory
Other examples where tMas can be used as controls are shown in the table below. Positive Control Patient Sample Negative Control Orientation Spot
Quality control for Warthin-Starry staining
Patient Gastric Tissue Tissue Microarray Positive and Negative Controls Orientation Spot
Patient sample (Gastric)
Negative control TMA Patient sample (Gastric)