Re-epithelialization from human skin explant cultures is promoted by ligand-activated HER3 receptor

Tissue-resident memory T cells (TRM) persist locally in nonlymphoid tissues where they provide frontline defense against recurring insults. TRM at barrier surfaces express the markers CD103 and/or CD69, which function to retain them in epithelial tissues. In humans, neither the long-term migratory behavior of TRM nor their ability to reenter the circulation and potentially migrate to distant tissue sites has been investigated. Using tissue explant cultures, we found that CD4+CD69+CD103+ TRM in human skin can down-regulate CD69 and exit the tissue. In addition, we identified a skin-tropic CD4+CD69−CD103+ population in human lymph and blood that is transcriptionally, functionally, and clonally related to the CD4+CD69+CD103+ TRM population in the skin. Using a skin xenograft model, we confirmed that a fraction of the human cutaneous CD4+CD103+ TRM population can reenter circulation and migrate to secondary human skin sites where they reassume a TRM phenotype. Thus, our data challenge current concepts regarding the strict tissue compartmentalization of CD4+ T cell memory in humans.

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Keratinocyte outgrowth from human skin explant cultures is dependent upon p38 signaling

Wound Repair and Regeneration ◽

10.1046/j.1524-475x.2003.11506.x ◽

2003 ◽

Vol 11 (5) ◽

pp. 346-353 ◽

Cited By ~ 18

Author(s):

Stefan W. Stoll ◽

Sanjay Kansra ◽

James T. Elder

Keyword(s):

Human Skin ◽

Explant Cultures

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An in vitro model for detecting skin irritants: methyl green-pyronine staining of human skin explant cultures

Toxicology in Vitro ◽

10.1016/s0887-2333(02)00039-5 ◽

2002 ◽

Vol 16 (5) ◽

pp. 581-588 ◽

Cited By ~ 19

Author(s):

J.J.L Jacobs ◽

C Lehé ◽

K.D.A Cammans ◽

P.K Das ◽

G.R Elliott

Keyword(s):

Human Skin ◽

In Vitro Model ◽

Methyl Green ◽

Explant Cultures ◽

Vitro Model ◽

Skin Irritants

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Proteoglycan synthesis in human skin and burn scar explant cultures

Burns ◽

10.1016/0305-4179(91)90070-w ◽

1991 ◽

Vol 17 (6) ◽

pp. 452-457 ◽

Cited By ~ 9

Author(s):

H.G. Garg ◽

E.W. Lippay ◽

E.A. Carter ◽

M.B. Donelan ◽

J.P. Remensnyder

Keyword(s):

Human Skin ◽

Proteoglycan Synthesis ◽

Burn Scar ◽

Explant Cultures

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A web-like network of type vi collagen in human skin is revealed by immuno-electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103978 ◽

1988 ◽

Vol 46 ◽

pp. 382-383

Author(s):

Douglas R. Keene ◽

Robert W. Glanville ◽

Eva Engvall

Keyword(s):

Electron Microscopy ◽

Monoclonal Antibody ◽

Human Skin ◽

Basement Membranes ◽

Primary Antibody ◽

Fat Cells ◽

Secondary Antibody ◽

Type Vi Collagen ◽

Dermal Matrix ◽

Immuno Electron Microscopy

A mouse monoclonal antibody (5C6) prepared against human type VI collagen (1) has been used in this study to immunolocalize type VI collagen in human skin. The enbloc method used involves exposing whole tissue pieces to primary antibody and 5 nm gold conjugated secondary antibody before fixation, and has been described in detail elsewhere (2).Biopsies were taken from individuals ranging in age from neonate to 65 years old. By immuno-electron microscopy, type VI collagen is found to be distributed as a fine branching network closely associated with (but not attached to) banded collagen fibrils containing types I and III collagen (Fig. 1). It appears to enwrap fibers, to weave between individual fibrils within a fiber, and to span the distance separating fibers, creating a “web-like network” which entraps fibers within deep papillary and reticular dermal layers (Fig. 2). Relative to that in the dermal matrix, the concentration of type VI collagen is higher around endothelial basement membranes limiting the outer boundaries of nerves, capillaries, and fat cells (Fig. 3).

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Effect of Acetone and Kerosene on Skin Ultrastructure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093717 ◽

1972 ◽

Vol 30 ◽

pp. 92-93

Author(s):

A. P. Lupulescu ◽

H. Pinkus ◽

D. J. Birmingham

Keyword(s):

Electron Microscopy ◽

Human Skin ◽

Osmium Tetroxide ◽

Human Epidermis ◽

Ultrastructural Changes ◽

Chemical Agents ◽

Skin Ultrastructure ◽

Volar Surface

Our laboratory is engaged in the study of the effect of different chemical agents on human skin, using electron microscopy. Previous investigations revealed that topical use of a strong alkali (NaOH 1N) or acid (HCl 1N), induces ultrastructural changes in the upper layers of human epidermis. In the current experiments, acetone and kerosene, which are primarily lipid solvents, were topically used on the volar surface of the forearm of Caucasian and Negro volunteers. Skin specimens were bioptically removed after 90 min. exposure and 72. hours later, fixed in 3% buffered glutaraldehyde, postfixed in 1% phosphate osmium tetroxide, then flat embedded in Epon.

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Changes in corneocyte element concentrations occur in skin inner stratum corneum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134326 ◽

1990 ◽

Vol 48 (2) ◽

pp. 146-147

Author(s):

R. R. Warner

Keyword(s):

Stratum Corneum ◽

Human Skin ◽

Element Concentration ◽

Skin Barrier ◽

Barrier Properties ◽

Brick Wall ◽

Inorganic Elements ◽

Dry Skin ◽

Skin Biopsies ◽

Intercellular Lipid

Keratinocytes undergo maturation during their transit through the viable layers of skin, and then abruptly transform into flattened, anuclear corneocytes that constitute the cellular component of the skin barrier, the stratum corneum (SC). The SC is generally considered to be homogeneous in its structure and barrier properties, and is often shown schematically as a featureless brick wall, the “bricks” being the corneocytes, the “mortar” being intercellular lipid. Previously we showed the outer SC was not homogeneous in its composition, but contained steep gradients of the physiological inorganic elements Na, K and Cl, likely originating from sweat salts. Here we show the innermost corneocytes in human skin are also heterogeneous in composition, undergoing systematic changes in intracellular element concentration during transit into the interior of the SC.Human skin biopsies were taken from the lower leg of individuals with both “good” and “dry” skin and plunge-frozen in a stirred, cooled isopentane/propane mixture.

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Desmosomal distribution in the epidermis of a non-contracting human skin equivalent

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124884 ◽

1992 ◽

Vol 50 (1) ◽

pp. 896-897

Author(s):

L.X. Oakford ◽

S.D. Dimitrijevich ◽

R. Gracy

Keyword(s):

Human Skin ◽

Basal Layer ◽

Skin Equivalent ◽

Tissue Component ◽

Intact Skin ◽

Similar Sequence ◽

Sequence Of Events ◽

Suprabasal Keratinocytes ◽

Human Skin Equivalent

In intact skin the epidermal layer is a dynamic tissue component which is maintained by a basal layer of mitotically active cells. The protective upper epidermis, the stratum corneum, is generated by differentiation of the suprabasal keratinocytes which eventually desquamate as anuclear comeocytes. A similar sequence of events is observed in vitro in the non-contracting human skin equivalent (HSE) which was developed in this lab (1). As a part of the definition process for this model of living skin we are examining its ultrastructural features. Since desmosomes are important in maintaining cell-cell interactions in stratified epithelia their distribution in HSE was examined.

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