Gingivitis and Eosinophils ROLF APPELGREN, EDWARD J. KAMINSKI, RICHARD J. OGLESBY, and PETER J. ROBINSON The Dental School, Northwestern University, 311, E. Chicago Avenue, Chicago, Illinois 60611, USA Kovacs (Experentia 6:349, 1950), Vercautern and Peeters (Arch Intern Pharmacodyn 89:10, 1952) and Broome and Archer (Nature 193: 446, 1961) reported that eosinophils carry substances capable of inactivating histamine. Archer and Broome (Nature 198:893, 1963) described eosinophil extracts capable of antagonizing serotonin and bradykinin as well as histamine. The principal function of eosinophils, therefore, appears to be one of a homeostatic nature controlling the severity or duration of inflammation, through antagonization of histamine, serotonin, and bradykinin. Using smears of gingival blood, Kutscher et al (J Periodont 93:102, 1953) reported no differences in the number of eosinophils between normal and severely inflamed gingiva. Yet, there are no reports available on the identification of extravascular eosinophils in gingiva. Therefore, the purpose of this study was to compare the frequency of extravascular eosinophils in human gingiva with varying degrees of inflammation. Sixty specimens of gingiva were obtained from 33 patients, 19 females and 14 males ranging in age from 17 to 70 years. Specimens were classified as to the degree of clinical inflammation according to the Gingival Index (GI) (L6E, J Periodont 38:610, 1967) immediately before excision of the specimen. The specimens had the following GI distributions: 19 = GI 1, 31GI 2, and 10 = GI 3. Specimens which were taken from the palatal, interproximal, and/or facial areas included both sulcular and oral epithelium and connective tissue. They were fixed in Newcomer's solution (isopropanol 60%, proprionic acid 30%, acetone 10%, and dioxane 10%). After fixation, specimens were embedded in paraffin, sectioned at 5 microns and stained with chromotrope 2R stain. Chromatropic stain, described by Lendrum (DRURY and WALLINGTON, Carleton's Histological Technique, Oxford University Press, New York/Toronto 1967) as being specific for the cytoplasmic granules of cosinophils, was used to identify the eosinophils. Sections were hydrated for two minutes, and stained with hemaReceived for publication August 3, 1976. Accepted for publication August 12, 1976.
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toxylin for two minutes, and washed in tap water for five minutes. Subsequently, sections were stained in chromotropic solution for /2 to 1 hour, rinsed in tap water, dehydrated, cleared in xylene, and mounted in Peromount. In this procedure, the eosinophils cytoplasm appears red and their nuclei blue. No eosinophils were located in any of the 60 sections examined. Control sections of human fibrous mucosa were stained with chromotrope 2R simultaneously with each gingival specimen. Control specimens consistently stained positively for eosinophils. S nce no eosinophils were found in the first 10 specimens fixed with Newcomer's solution and stained with chromotrope 2R, a series of control methods was initiated to eliminate any errors from the techniques used. Each specimen was divided in half, one-half fixed in formalin, the other half in Newcomer's fixative. Then each of the two differently fixed specimens were stained with chromotrope 2R, azo-eosin, Giemsa, and hematoxylin and eosin staining methods. This process was carried out for 15 specimens; since no differences in staining results of eosinophils were observed between the two methods of fixation, no further elaborate controls were carried out. The principal known role of eosinophils is as a histamine antagonizer. Histamine, in turn facilitates the spread of inflammation by aiding bacterial proteolytic enzymes to permeate connective tissues. The lack of eosinophils in gingiva could therefore be a reason why gingival inflammation is so pervasive. Alternatively, the absence of eosinophils could possibly indicate either that histamine does not have a significant role in gingivitis or that a mechanism exists in gingival tissues which inhibits the migration and aggregation of eosinophils to the site of inflammation. The number of circulating eosinophils has been demonstrated to decrease in the pres-
ence of ACTH (THORNE et al, JAMA 137: 1005, 1948). Additional studies are needed to establish whether the amount of tissue-released histamin, the amount of tissue-released histamine virus, the number of mast cells, or the amount of ACTH in gingivitis can possibly account for the absence of eosinophils in gingival tissues.
J Dent Res May 1977 Vol. 56 No. 5 Downloaded from jdr.sagepub.com at UNIV OF WESTERN ONTARIO on June 9, 2015 For personal use only. No other uses without permission.
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toxylin for two minutes, and washed in tap water for five minutes. Subsequently, sections were stained in chromotropic solution for /2 to 1 hour, rinsed in tap water, dehydrated, cleared in xylene, and mounted in Peromount. In this procedure, the eosinophils cytoplasm appears red and their nuclei blue. No eosinophils were located in any of the 60 sections examined. Control sections of human fibrous mucosa were stained with chromotrope 2R simultaneously with each gingival specimen. Control specimens consistently stained positively for eosinophils. S nce no eosinophils were found in the first 10 specimens fixed with Newcomer's solution and stained with chromotrope 2R, a series of control methods was initiated to eliminate any errors from the techniques used. Each specimen was divided in half, one-half fixed in formalin, the other half in Newcomer's fixative. Then each of the two differently fixed specimens were stained with chromotrope 2R, azo-eosin, Giemsa, and hematoxylin and eosin staining methods. This process was carried out for 15 specimens; since no differences in staining results of eosinophils were observed between the two methods of fixation, no further elaborate controls were carried out. The principal known role of eosinophils is as a histamine antagonizer. Histamine, in turn facilitates the spread of inflammation by aiding bacterial proteolytic enzymes to permeate connective tissues. The lack of eosinophils in gingiva could therefore be a reason why gingival inflammation is so pervasive. Alternatively, the absence of eosinophils could possibly indicate either that histamine does not have a significant role in gingivitis or that a mechanism exists in gingival tissues which inhibits the migration and aggregation of eosinophils to the site of inflammation. The number of circulating eosinophils has been demonstrated to decrease in the pres-
ence of ACTH (THORNE et al, JAMA 137: 1005, 1948). Additional studies are needed to establish whether the amount of tissue-released histamin, the amount of tissue-released histamine virus, the number of mast cells, or the amount of ACTH in gingivitis can possibly account for the absence of eosinophils in gingival tissues.
J Dent Res May 1977 Vol. 56 No. 5 Downloaded from jdr.sagepub.com at UNIV OF WESTERN ONTARIO on June 9, 2015 For personal use only. No other uses without permission.
