Skip to main content
Xiying Fan

Xiying Fan

•HS Assistant Clinical Professor, Department of Dermatology
•Director of Phototherapy, UC Irvine, CA

Biography

Xiying Fan, MD, PhD, is Health Sciences Assistant Clinical Professor and Director of Phototherapy in the Department of Dermatology at UC Irvine School of Medicine. He completed his PhD in Immunology and Microbial Pathogenesis at Weill Cornell Medicine under the mentorship of Alexander Rudensky, where his dissertation focused on features of tissue-resident and recirculating lymphocytes. He earned his MD through the Tri-Institutional MD/PhD Program at Weill Cornell Medicine and completed his dermatology residency at UC Irvine, where he served as Co-Chief Resident.

Fan's research has focused on tissue-resident lymphocytes and regulatory T cells, with publications in journals including Nature, Science, Immunity, and Cell. His work has examined how commensal bacteria metabolites promote regulatory T-cell generation, the tissue residency of innate lymphoid cells, and the functional maturation of regulatory T cells that survey skin and vascular tissues. He was supported by an F30 Individual Predoctoral NRSA Fellowship from the NIH during his graduate training.

Fan's clinical interests include cutaneous lymphomas, supportive oncodermatology, complex medical dermatology, and inpatient consultative dermatology. He is board certified by the American Board of Dermatology and is a Fellow of the American Academy of Dermatology. He serves on the Residency Application Committee and participates in the Melanoma Tumor Board and Cutaneous Lymphoma Tumor Board at UC Irvine.

Return to top

Education

  • BA (Honors) in Molecular and Cell Biology, UC Berkeley, 2009
  • PhD in Immunology and Microbial Pathogenesis, Weill Cornell Medicine, 2018
  • MD, Weill Cornell Medicine, 2020
Return to top

Distinctions

  • Department of Molecular and Cell Biology Outstanding Scholar Award, UC Berkeley, 2009
  • Phi Beta Kappa, 2009
  • NIAID Postbaccalaureate Intramural Research Award, 2009-2011
  • Medical Dermatology Society Mentorship Award, 2023
  • UC Berkeley Regents' and Chancellor's Scholarship, 2005-2009
  • Fellow, American Academy of Dermatology, 2024
  • UC Irvine Dermatology Resident Teacher of the Year, 2024
  • College of Letters and Science Dean's List, UC Berkeley, 2005-2009
Return to top

Areas of Expertise

  • Dermatology
  • Mycosis Fungoides
  • Cutaneous T-cell Lymphoma
  • Supportive Oncodermatology
  • Complex Medical Dermatology
  • Mastocytosis
  • Parabiosis
  • Immunology
  • Tissue-Resident Lymphocytes

Recent Publications

  • Seiger K, Driscoll B, Messele F, Golbari N, FAN X, Holmes J, Zachary C, “Use of Optical Coherence Tomography to Assess Properties of Cutaneous Defects Following Radiofrequency Microneedling and Laser Treatment” (opens in new tab), Lasers in Surgery and Medicine, vol. 56, no. 9, pp. 762-769, 2024.
  • Kincaid CM, Phong C, Arnold JD, FAN X, Lee BA, Mesinkovska NA, “Primary cutaneous lymphoma in a patient with mastocytosis: Is there an association?” (opens in new tab), Jaad Case Reports, vol. 36, pp. 70-72, 2023.
  • Zeis P, Lian M, FAN X, Herman JS, Hernandez DC, Gentek R, Elias S, Symowski C, Knöpper K, Peltokangas N, Friedrich C, Doucet-Ladeveze R, Kabat AM, Locksley RM, Voehringer D, Bajenoff M, Rudensky AY, Romagnani C, Grün D, Gasteiger G, “In Situ Maturation and Tissue Adaptation of Type 2 Innate Lymphoid Cell Progenitors”, Immunity, vol. 53, no. 4, pp. 775-792, 2020.
  • Adams NM, Lau CM, FAN X, Rapp M, Geary CD, Weizman OE, Diaz-Salazar C, Sun JC, “Transcription Factor IRF8 Orchestrates the Adaptive Natural Killer Cell Response”, Immunity, vol. 48, no. 6, pp. 1172-1182.e6, 2018.
  • FAN X, Moltedo B, Mendoza A, Davydov AN, Faire MB, Mazutis L, Sharma R, Pe'er D, Chudakov DM, Rudensky AY, “CD49b defines functionally mature Treg cells that survey skin and vascular tissues”, J Exp Med, vol. 215, no. 11, pp. 2796-2814, 2018.
  • Stamatiades EG, Tremblay ME, Bohm M, Crozet L, Bisht K, Kao D, Coelho C, FAN X, Yewdell WT, Davidson A, Heeger PS, Diebold S, Nimmerjahn F, Geissmann F, “Immune Monitoring of Trans-endothelial Transport by Kidney-Resident Macrophages”, Cell, vol. 166, no. 4, pp. 991-1003, 2016.
  • O'Sullivan TE, Rapp M, FAN X, Weizman OE, Bhardwaj P, Adams NM, Walzer T, Dannenberg AJ, Sun JC, “Adipose-Resident Group 1 Innate Lymphoid Cells Promote Obesity-Associated Insulin Resistance”, Immunity, vol. 45, no. 2, pp. 428-41, 2016.
  • Chinen T, Kannan AK, Levine AG, FAN X, Klein U, Zheng Y, Gasteiger G, Feng Y, Fontenot JD, Rudensky AY, “An essential role for the IL-2 receptor in Treg cell function”, Nat Immunol, vol. 17, no. 11, pp. 1322-1333, 2016.
  • FAN X, Rudensky AY, “Hallmarks of Tissue-Resident Lymphocytes”, Cell, vol. 164, no. 6, pp. 1198-211, 2016.
  • Gasteiger G, FAN X, Dikiy S, Lee SY, Rudensky AY, “Tissue residency of innate lymphoid cells in lymphoid and nonlymphoid organs”, Science, vol. 350, no. 6263, pp. 981-5, 2015.
  • Wang HY, Ma CA, Zhao Y, FAN X, Zhou Q, Edmonds P, Uzel G, Oliveira JB, Orange J, Jain A, “Antibody deficiency associated with an inherited autosomal dominant mutation in TWEAK”, Proc Natl Acad Sci U S A, vol. 110, no. 13, pp. 5127-32, 2013.
  • Arpaia N, Campbell C, FAN X, Dikiy S, van der Veeken J, deRoos P, Liu H, Cross JR, Pfeffer K, Coffer PJ, Rudensky AY, “Metabolites produced by commensal bacteria promote peripheral regulatory T-cell generation”, Nature, vol. 504, no. 7480, pp. 451-5, 2013.
  • FAN X, Upadhyaya B, Wu L, Koh C, Santín-Durán M, Pittaluga S, Uzel G, Kleiner D, Williams E, Ma CA, Bodansky A, Oliveira JB, Edmonds P, Hornung R, Wong DW, Fayer R, Fleisher T, Heller T, Prussin C, Jain A, “CD40 agonist antibody mediated improvement of chronic Cryptosporidium infection in patients with X-linked hyper IgM syndrome”, Clin Immunol, vol. 143, no. 2, pp. 152-61, 2012.
  • Jain A, Kovacs JA, Nelson DL, Migueles SA, Pittaluga S, Fanslow W, FAN X, Wong DW, Massey J, Hornung R, Brown MR, Spinner JJ, Liu S, Davey V, Hill HA, Ochs H, Fleisher TA, “Partial immune reconstitution of X-linked hyper IgM syndrome with recombinant CD40 ligand”, Blood, vol. 118, no. 14, pp. 3811-7, 2011.
  • FAN X, Hussien R, Brooks GA, “H2O2-induced mitochondrial fragmentation in C2C12 myocytes”, Free Radic Biol Med, vol. 49, no. 11, pp. 1646-54, 2010.
Return to top

Contact Information

Email: xiyingf@uci.edu

Phone: (949) 824-5515

Address: 118 Medical Surge 1, Irvine, CA 92697

Return to top

This profile was created with the help of AI.

Last updated on 6/15/2026.