THE JOURNAL OF NVESTOATVE DERMATOLOGY Copyright 1565 by The Williams & Wilkins Co. Vol. 45, No. 2 Printed in U.S.A. ELASTC GLOBES N HUMAN SKN* HERMANN PNKUS, MD., AMR H. MEHREGAN, MD. AND RENATO G. STARCCO, MD. The normal and pathologic morphology and chemistry of elastic fibers in human skin have been subject of renewed investigation during the past decade (1, 2, 3). New staining reactions and the availability of certain enzymes (4) that will attack elastic fibers comprise additional tools of investigation. Normally, clastin is found in the skin in tbe shape of fibers of varying caliber, or of ribbons that are presumably composed of fibrillar units. MATERALS AND METHODS The materials used for this study consisted of the following: A. A collection of thirty thousand skin biopsy stained routinely with hematoxylin and eosin and with acid orcein and giemsa ( & G). This group includes many different dermatoses and skin from all age groups and every part of the body surface. B. Thirty of skin were obtained from five individuals not suffering from skin disease. Case 1 w/f 78 Biopsy Case 2 w/f 658 Biopsy Case 3 c/m 62 8 Biopsy Case 4 w/m 23 3 Biopsy Case 5 w/m 24 3 Biopsy TABLE Distribution of elastic globes in normal human skin, one biopsy specimen with elastic globes;, two biopsy with elastic globes;, one biopsy specimen with no elastic globe;, two biopsy with no elastic globe. The purpose of this paper is to call attention to the fact that normal skin of most individuals contains, in specific localization, elastin in the shape of small globes, in nonfibrillar form. No explanation or speculation concerning the origin of these elastic globes (E.G.) is offered, but their sometime significance in diagnostic evaluation of a skin biopsy will be discussed. Received for publication July 27, 1964. Supported in part by research grant AM 71943 from the U.S. Public Health Service through the National nstitute of Health. * From tbe Departments of Dermatology, Wayne State University College of Medicine and Detroit Receiving Hospital, Detroit, Michigan. Thigh Calf Arm Forearm Abdomen 81 Chest 5ealp nformation regarding the age, sex, race, and sites of the is given in Table. Sections obtained from these and thirty other biopsies selected from group A were stained with O & G, Gomori's aldehyde fuchsin, and Verhocff's methods for elastic fibers according to the Armed Forces' Manual of Histologic and Special Staining Technics (5). C. Multiple paraffin sections from five selected because they contained well developed E.G. were mounted on slides. One half of the sections on each slide was covered with a solution of.5% collodium in etheralcohol and the slides were then immersed for one hour at 37 C either in 1% solution of Trypsin 1:3 or in.2% solution of clastase 2X crystalline in phospbate buffer at ph 8.4. The slides were then washed in distilled water and stained with acid orcein.
82 THE JOURNAL OF NVESTGATVE DERMATOLOGY 4ff 9 4 :.. 4 t a_v.1 7. Bb1 t' J '' 4' FG. 1. A. Normal skin of the arm shows two small elastic globes. Acid orceingiemsa, 19 X. B. Normal skin of the leg shows in a larger magnification an elastic globe in its characteristic localization. Acid orceingiemsa, 6X.
ip,. Ct:*f..'ti7'" i;.._..; ;4tr S.e,_ st' UP S'.. t. '. :: r. ' ::.t;i '.:,yç 4i:.4,,V... 'r' sd..., 'S.. '. S _: a 1 sal.. 'C. a,y: r... ' % _ '. '.. '.. cj. ELASTC GLOBES N HUMAN SKN 83.....et.. _.?. S...a ) ' FG. 2. Normal skin of thg leg shows elastic globes in one side of the section. Other side was digested with elastase. The elastic globes as well as the elastic fibers are completely absent. Acid orceingiemsa, 19X. OBSERVATONS AND CONCLUSONS Elastic globes are spherical, ovoid, or somewhat irregular bodies (Fig. 1) stainable by all methods for the demonstration of elastic fibers and digested by the enzymes that attack elastic tissue (Fig. 2). They measure anywhere from 3 15 microns. They are found in normal skin in characteristic localization at or near the network of fine elastic fibers from which the papillary fibers extend toward the epidermis. Occasionally they descend a little deeper around hair follicles and ecerine duets. They are not present on the entire body surface, rather are restricted to the face and the upper and lower extremities (Table 1). They are found not only in adults, but are present in identical form in young children. n some individuals, they are relatively littledeveloped and must be searched for, however, they were present in all five of our normalskin subjects. Some Specimens of our collection of of pathologic skin contained many more and larger E.G. than others (Fig. 3). However, there was no correlation between their development and any disease or group of diaeases. t Seems more likely that these are considerable individual differences. The E.G. usually seem to lie free in the tis Sue, but sometimes are attached to fine elastic fibers. The Smaller ones stain homogeneously, a few of the larger ones have a more deeply stained shell and paler center. Their presence has no relation to sun exposure as might be suggested by their distribution on extremities and face. They occur in young and old individuals alike, and also on those parts of the extremities that are much less exposed or ordinarily are covered by inoes and socks. n skin that shows actinie elastosis, their identity often is lost in the general derangement of elastic tissue. The limited occurrence of E.G. in certain areas of skin makes topographic identification of unknown easier and may at times be of assistance in eriminologic work. The constant relationship to the superficial
84 THR JOURNAL OF NVESTGATVE DERMATOLOGY p 4? s' 1 F: Fie. 3. A. n pathologic materials the elastic globes are sometimes more numerous and larger in size. Acid orceingiemsa, 171X. B. A higher magnification shows dense shell with light staining center of the large globes. Acid orcemgiemsa, 54X.
ELASTC GLOBES N HUMAN SKN 85 'a Fio. 4. Superficial basal cell epithelioma with its cbaracteristic fibrous mesodermal stroma growing beneath the epidermis in the upper corium. Presence of the elastic globes beneath the tumor indicates the superficial nature of the growth. Acid orceingiemsa, 135X. net of elastic fibers makes E.G. helpful in the interpretation of histopathologic findings in some skin biopsy. n inflammatory infiltrates that destroy elastic fibers, the globes often prove a little more resistant. Their presence then indicates tbat elastic fibers also were present before inflammation set in, and their topical relation to the infiltrate indicates whether the latter is superficial or deep. Their significance is perhaps greater in tumors as shown in Fig. 4. f a basal cell epithclioma is found above a row of E.G. it is safe to assume that the tumor is very superficial and occupies only the pars papillaris. f E.G. are present above it, then the tumor involves the pars rcticularis of the coriuin. While histologic examination gives no indication on how elastic globes are formed, their very existence is of some biologic interest as a sign that the protein elastin must not necessarily assume fibrillar configuration in contrast to collagen which apparently always occurs as structured fibrils. SUMMARY Attention is called to the presence of clastin in the nonfibrillar form of small globes in the subpapillary layer of the corium in normal human skin of the face and extremities. Some areas of significance of these elastic globes arc pointed out. REFERENCES 1. Smith, J. Graham, Jr., M. D.: The dermal elastoses. Arch. Derm. (Chicago), 88: 3S2, 1963. 2. LedonxCorbusier, M.: Lc tissu elastique cutané. Arch. Belg. Derm. Syph., 18: Si, 1962. 3. Winer,. Louis: Elastic fibers in unusual dermatoses. Arch. Derm. (Chicago), 71: 338, 1955. 4. Mandl,.: Collagenases and elastases. Advances Enzym., 23: 163, 1961. 5. Armed Forces nstitute of Pathology: Manual of Histologic and Special Staining Technics. Second Edition. The Blakiston Division Mc GrawHill Book Co., nc.