Abstract
We acknowledge the fact that our article has been very critically examined by Dr. Annette Listser. Nevertheless, we would like to answer her criticism because many of the so-called discrepancies are only due to the fact that a different staining procedure was used by our team. This new procedure allowed us, for the first time, to clearly and simultaneously detect and quantify, in paraffin-embedded tissues from cats, all mast cell subtypes, without any need to use mathematical extrapolations. We will address the three comments as follows:
1. When in the abstract we state “it is the first time that MCc have been identified,” we refer to the presence of chymase containing MC detected on double-stained slides, in which it was possible to simultaneously detect MCt (red stained), MCc (blue stained), and MCtc (purple stained). In previous publications, 1,2 no double staining was performed for quantification of mast cell subtypes, but only serial sections were stained for either chymase or tryptase. The authors of these articles assumed that MCc should have been present in feline skin because the number of MCc was usually higher than that of MCt. However, the percentages of mast cells reported by the authors were only mathematical extrapolations, but they could not really prove the presence of MCc. In our article, we could prove the presence of MCc and the statement “it is the first time that MCc have been identified” is thus true.
2. Beadlestone et al. 1 worked on frozen sections using histochemistry to detect both chymase and tryptase. The double-labeling method they used for chymase and tryptase detection gave negative results. Attempts of sequential staining using chymase followed by tryptase did not allow any classification, whereas attempts of sequential staining using tryptase followed by chymase resulted in no staining. MCt quantification in the abdomen (based on tryptase-stained slides) was 60.22 cells/mm2, and MCc quantification was 53.96 cells/mm2. By mathematical extrapolation of these data, a 90% of MCtc ((53.96 × 100)/60.22 = 89.60) has been estimated.
3. In the article by Noviana et al., 2 the experiments have been conducted using the Carnoy fixative and an enzyme histochemical method (no double-labeling procedure). The counts and distribution of MCt and MCc were compared by means of successive staining, and again (as in the article by Beadlestone et al. 1 ) some of the results are mathematical extrapolations of numerical data. This article has not been included in the reference list because the work is similar to that of Beadlestone, but it was published later.