{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T17:23:50Z","timestamp":1777397030020,"version":"3.51.4"},"reference-count":15,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2020,9,30]],"date-time":"2020-09-30T00:00:00Z","timestamp":1601424000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,3,24]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Senile lentigo or age spots are hyperpigmented macules of skin that commonly develop following long-term exposure to ultraviolet radiation. This condition is caused by accumulation of large numbers of melanosomes (melanin granules) produced by melanocytes within neighboring keratinocytes. However, there is still no consensus regarding the melanosome transfer mechanism in senile lentigo. To date, most pathohistological studies of skin have been two-dimensional and do not provide detailed data on the complex interactions of the melanocyte\u2013keratinocyte network involved in melanosome transfer.<\/jats:p><jats:p>We performed a three-dimensional reconstruction of the epidermal microstructure in senile lentigo using three different microscopic modalities to visualize the topological melanocyte\u2013keratinocyte relationship and melanosome distribution. Confocal laser microscopy images showed that melanocyte dendritic processes are more frequently branched and elongated in senile lentigo skin than in normal skin. Serial transmission electron micrographs showed that dendritic processes extend into intercellular spaces between keratinocytes. Focused ion beam-scanning electron micrographs showed that dendritic processes in senile lentigo encircle adjacent keratinocytes and accumulate large numbers of melanosomes. Moreover, melanosomes transferred to keratinocytes are present not only in the supranuclear area but throughout the perinuclear area except on the basal side.<\/jats:p><jats:p>The use of these different microscopic methods helped to elucidate the three-dimensional morphology and topology of melanocytes and keratinocytes in senile lentigo. We show that the localization of melanosomes in dendritic processes to the region encircling recipient keratinocytes contributes to efficient melanosome transfer in senile lentigo.<\/jats:p>","DOI":"10.1093\/jmicro\/dfaa054","type":"journal-article","created":{"date-parts":[[2020,9,10]],"date-time":"2020-09-10T13:19:01Z","timestamp":1599743941000},"page":"224-231","source":"Crossref","is-referenced-by-count":18,"title":["Three-dimensional structure analysis of melanocytes and keratinocytes in senile lentigo"],"prefix":"10.1093","volume":"70","author":[{"given":"Yuki","family":"Mizutani","sequence":"first","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mika","family":"Yamashita","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rie","family":"Hashimoto","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6470-9949","authenticated-orcid":false,"given":"Toru","family":"Atsugi","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akemi","family":"Ryu","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akinobu","family":"Hayashi","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yukiko","family":"Rikimaru-Nishi","sequence":"additional","affiliation":[{"name":"Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011 Japan"},{"name":"Department of Plastic and Reconstructive Surgery, and Maxillofacial Surgery, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keisuke","family":"Ohta","sequence":"additional","affiliation":[{"name":"Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011 Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2020,9,30]]},"reference":[{"key":"2021032412094573700_R1","doi-asserted-by":"crossref","first-page":"1256","DOI":"10.1111\/j.0022-202X.2004.22503.x","article-title":"The epidermal stem cell factor is over-expressed in lentigo senilis: implication for the mechanism of hyperpigmentation","volume":"122","author":"Hattori","year":"2004","journal-title":"J. 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