The Warthin-Starry stain relies on the ability of certain bacteria and spirochaetes to bind silver ions from solution. This reaction is an argyrophil reaction similar to the Reticulin special stain. Subsequent addition of a reducing agent then converts this bound silver to visible metallic silver. In the Warthin-Starry stain, the tissue is sensitised prior to application of the silver complex. An aqueous silver nitrate solution combined with the reducing agent is applied, and a silver diamine complex is generated.
The main method for carrying out this technique is listed below
1. Take sections to water.
2. Rinse sections in pH 3.6 buffer
3. Stain with pre-heated 1% silver nitrate for 1½-1¾hours at 55-60°C.
4. Make up developer just before use. Now treat sections with developer for between 30 seconds to 2 minutes, checking colouration of the slide. May require longer to reach required colour. The sections should turn golden brown.
5. Now rinse in hot tap water for several minutes at 55-60°C then in room temperature buffer at pH 3.6.
6. Tone on 0.2% gold chloride for 5 minutes.
7. Wash in water
8. Fix in 5% hypo for 3 minutes.
9. Wash in water.
10. Dehydrate, clear and mount.
Photo x10 Warthin Starry