New Bolton Center Kennett Square, PA
Emergencies & Appointments:
Ryan Hospital Philadelphia, PA


Anatomic Pathology Board Certificate (American Board of Pathology)

Assistant Professor, Biomedical Sciences, University of Pennsylvania School of Veterinary Medicine

Member, Institute for Regenerative Medicine, University of Pennsylvania School of Medicine

Research Areas: Germ cell biology, Spermatogenesis, Human development, Epigenetic reprogramming, Gonadogenesis, Primate embryology, Embryonic stem cells, Stem cell biology, Genitourinary Pathology
PubMed Link
Contact Information:
School of Veterinary Medicine

Our lab focuses on understanding the molecular mechanisms of human germline development using single cell genomics and in vitro reconstitution.
We have identified the origin and the comprehensive developmental roadmap of primordial germ cells (PGCs), the precursors both for oocytes and spermatozoa, in non-human primates (Dev Cell 2016, 39:169). Moreover, we have successfully reconstituted human primordial germ cell-like cells (hPGCLCs) in vitro from pluripotent stem cells (Cell Stem Cell 2015, 17:178). These studies provide the platform for the mechanistic dissection of the human germline specification pathway as well as the further reconstitution of human gametogenesis in vitro. Our studies of germ cell biology in human/non-human primates not only advance our understanding of the most fundamental part of life but also directly links to many clinical applications, such as infertility treatment and screening for the potential causes of infertility.

Dr. Sasaki's clinical expertise includes renal pathology and genitourinary pathology

Yamashiro, C., Sasaki, K., Yabuta, Y., Kojima, Y., Nakamura, T., Okamoto, I., Yokobayashi, S., Murase, Y., Ishikura, Y., Shirane, K., Sasaki, H., Yamamoto, T., Saitou, M. Generation of human oogonia from induced pluripotent stem cells in vitro [PMID 30237246] Science 19: 356-360, 2018.

Nakamura, T., Yabuta, Y., Okamoto, I., Sasaki, K., Iwatani, C., Tsuchiya, H., Saitou, M. Single-cell transcriptome of early embryos and cultured embryonic stem cells of cynomolgus monkeys [PMID 28649393] Sci Data 4: 170067, 2017.

Kojima, Y., Sasaki, K., Yokobayashi, S., Sakai, Y., Nakamura, T., Yabuta, Y., Nakaki, F., Nagaoka, S., Woltjen, K., Hotta, A., Yamamoto, T., Saitou, M. Evolutionarily distinctive transcriptional and signaling programs drive human germ cell lineage specification from pluripotent stem cells [PMID 28985527] Cell Stem Cell 21: 517-532.e5, 2017.

Miyauchi, H., Ohta, H., Nagaoka, S., Nakaki, F., Sasaki, K., Hayashi, K., Yabuta, Y., Nakamura, T., Yamamoto, T., Saitou, M. Bone morphogenetic protein and retinoic acid synergistically specify female germ-cell fate in mice [PMID 28928204] Embo J 36: 3100-3119, 2017.

Sasaki, K., Nakamura, T., Okamoto, I., Yabuta, Y., Iwatani, C., Tsuchiya, H., Seita, Y., Nakamura, S., Shiraki, N., Takakuwa, T., Yamamoto, T., Saitou, M. The germ cell fate of cynomolgus monkeys is specified in the nascent amnion [PMID 27720607] Dev Cell 39: 169-185, 2016.

Nakamura, T., Okamoto, I., Sasaki, K., Yabuta, Y., Iwatani, C., Tsuchiya, H., Seita, Y., Nakamura, S., Yamamoto, T., Saitou, M. A developmental coordinate of pluripotency among mice, monkeys and humans [PMID 27556940] Nature 537: 57-62, 2016.

Dai, D. F., Sasaki, K., Lin, M. Y., Smith, K. D., Nicosia, R. F., Alpers, C. E., Najafian, B. Interstitial eosinophilic aggregates in diabetic nephropathy: allergy or not? [PMID 25813275] Nephrol Dial Transplant 30: 1370-6, 2015.

Sasaki, K., Yokobayashi, S., Nakamura, T., Okamoto, I., Yabuta, Y., Kurimoto, K., Ohta, H., Moritoki, Y., Iwatani, C., Tsuchiya, H., Nakamura, S., Sekiguchi, K., Sakuma, T., Yamamoto, T., Mori, T., Woltjen, K., Nakagawa, M., Yamamoto, T., Takahashi, K., Yamanaka, S., Saitou, M. Robust in vitro induction of human germ cell fate from pluripotent stem cells [PMID 26189426] Cell Stem Cell 17: 178-94, 2015.

Sis, B., Bagnasco, S. M., Cornell, L. D., Randhawa, P., Haas, M., Lategan, B., Magil, A. B., Herzenberg, A. M., Gibson, I. W., Kuperman, M., Sasaki, K., Kraus, E. S. Isolated endarteritis and kidney transplant survival: a multicenter collaborative study [PMID 25381427] J Am Soc Nephrol 26: 1216-27, 2015.

Sasaki, K., Anderson, E., Shankland, S. J., Nicosia, R. F. Diffuse proliferative glomerulonephritis associated with cetuximab, an epidermal growth factor receptor inhibitor [PMID 23474009] Am J Kidney Dis 61: 988-91, 2013.

Sasaki, K., Chang, A., Najafian, B. Indolent systemic mastocytosis associated with light chain deposition disease [PMID 26019820] Clin Kidney J 5: 424-7, 2012.

Sasaki, K., Kumar, S., Chenal, M. E., Nicosia, R. F. Intraglomerular micrometastasis of squamous cell carcinoma [PMID 25874083] Clin Kidney J 5: 292-6, 2012.

Sasaki, K., Bastacky, S. I., Hrebinko, R. L., Parwani, A. V., Zynger, D. L. Glomus tumor of the kidney: case report and literature review [PMID 19164408] Int J Surg Pathol 19: 393-7, 2011.

Sasaki, K., Kohanbash, G., Hoji, A., Ueda, R., McDonald, H. A., Reinhart, T. A., Martinson, J., Lotze, M. T., Marincola, F. M., Wang, E., Fujita, M., Okada, H. miR-17-92 expression in differentiated T cells - implications for cancer immunotherapy [PMID 20167088] J Transl Med 18: 17, 2010.

Sasaki, K., Desimone, M., Rao, H. R., Huang, G. J., Seethala, R. R. Adrenocortical carcinosarcoma: a case report and review of the literature [PMID 20687934] Diagn Pathol 5: 51, 2010.

Sasaki, K., Parwani, A. V., Demetris, A. J., Sasatomi, E. Heterotopic breast epithelial inclusion of the heart: report of a case [PMID 20717001] Am J Surg Pathol 34: 1555-9, 2010.

Fujita, M., Zhu, X., Ueda, R., Sasaki, K., Kohanbash, G., Kastenhuber, E. R., McDonald, H. A., Gibson, G. A., Watkins, S. C., Muthuswamy, R., Kalinski, P., Okada, H. Effective immunotherapy against murine gliomas using type 1 polarizing dendritic cells--significant roles of CXCL10 [PMID 19190335] Cancer Res 15: 1587-95, 2009.

Ueda, R., Fujita, M., Zhu, X., Sasaki, K., Kastenhuber, E. R., Kohanbash, G., McDonald, H. A., Harper, J., Lonning, S., Okada, H. Systemic inhibition of transforming growth factor-beta in glioma-bearing mice improves the therapeutic efficacy of glioma-associated antigen peptide vaccines [PMID 19861464] Clin Cancer Res 15: 6551-9, 2009.

Sasaki, K., Pardee, A. D., Qu, Y., Zhao, X., Ueda, R., Kohanbash, G., Bailey, L. M., Okada, H., Muthuswamy, R., Kalinski, P., Basse, P. H., Falo, L. D., Storkus, W. J. IL-4 suppresses very late antigen-4 expression which is required for therapeutic Th1 T-cell trafficking into tumors [PMID 19752754] J Immunother 32: 793-802, 2009.

Sasaki, K., Bastacky, S. I., Zynger, D. L., Parwani, A. V. Use of immunohistochemical markers to confirm the presence of vas deferens in vasectomy specimens [PMID 19926581] Am J Clin Pathol 132: 893-8, 2009.

Ueda, R., Kohanbash, G., Sasaki, K., Fujita, M., Zhu, X., Kastenhuber, E. R., McDonald, H. A., Potter, D. M., Hamilton, R. L., Lotze, M. T., Khan, S. A., Sobol, R. W., Okada, H. Dicer-regulated microRNAs 222 and 339 promote resistance of cancer cells to cytotoxic T-lymphocytes by down-regulation of ICAM-1 [PMID 19520829] Proc Natl Acad Sci U S A 106: 10746-51, 2009.

Sasaki, K., Pardee, A. D., Okada, H., Storkus, W. J. IL-4 inhibits VLA-4 expression on Tc1 cells resulting in poor tumor infiltration and reduced therapy benefit [PMID 18958887] Eur J Immunol 38: 2865-73, 2008.

Fujita, M., Zhu, X., Sasaki, K., Ueda, R., Low, K. L., Pollack, I. F., Okada, H. Inhibition of STAT3 promotes the efficacy of adoptive transfer therapy using type-1 CTLs by modulation of the immunological microenvironment in a murine intracranial glioma [PMID 18250414] J Immunol 180: 2089-98, 2008.

Sasaki, K., Zhao, X., Pardee, A. D., Ueda, R., Fujita, M., Sehra, S., Kaplan, M. H., Kane, L. P., Okada, H., Storkus, W. J. Stat6 signaling suppresses VLA-4 expression by CD8+ T cells and limits their ability to infiltrate tumor lesions in vivo [PMID 18566374] J Immunol 181: 104-8, 2008.

MD (Medicine) Hokkaido University School of Medicine, 2005

PhD (Medicine) Kyoto University Graduate School of Medicine, 2017

Anatomic Pathology Board Certificate (American Board of Pathology)

University of Pittsburgh Medical Center (2008 to 2011)
Anatomic Pathology

University of Washington Medical Center (2011 to 2012)
Renal Pathology