Krishanu Saha, Ph.D.'s picture
Krishanu
Saha, Ph.D.
Assistant Professor
Departments of Biomedical Engineering and Medical History & Bioethics
Wisconsin Institute for Discovery

University of Wisconsin-Madison

Biography

Krishanu Saha is an Assistant Professor in the Department of Biomedical Engineering at the University of Wisconsin-Madison. He is also a member of the Wisconsin Institute for Discovery (WID) in the bionanocomposite tissue engineering scaffolds theme. Prior to his arrival in Madison, Dr. Saha studied Chemical Engineering at Cornell University and at the University of California in Berkeley. In 2007 he became a Society in Science: Branco-Weiss fellow in the laboratory of Professor Rudolf Jaenisch at the Whitehead Institute for Biomedical Research at MIT and in the Science and Technology Studies program at Harvard University with Professor Sheila Jasanoff in Cambridge, Massachusetts. At UW-Madison, his lab is now funded by the NIH, NSF and EPA to perform high-impact research on pluripotent stem cells, regenerative medicine, disease modeling and synthetic biology. His lab has developed a wide array of engineering approaches that seek to generate new cells, organoids and tissues from patient samples, as well as a suite of gene-editing technologies to knockout, correct or insert transgenes into human cells. He is a Member of the Forum on Regenerative Medicine organized by the National Academies of Sciences, Engineering and Medicine.

Title of Abstract

Precise Gene Editing of Human Cells using the CRISPR-Cas9 System

Presenting Author

Krishanu Saha

Abstract

Gene-edited, cell therapies constitute an emerging new class of regenerative medicine therapies. Gene editing can correct pathogenic or risk variants within autologous or allogenic cell sources and/or introduce new synthetic functionality through the used of engineered receptors and/or genetic circuits. Here we describe novel strategies to improve the CRISPR-Cas9 gene editing process during the manufacturing of human T cells and human iPS cells. 

The CRISPR-Cas9 system can generate DNA breaks at specific target sequences in the human genome. After DNA break formation, DNA repair within cells is accomplished through two major pathways: homology directed repair (HDR), which uses a donor DNA strand as a template for precise repair, and inherently error-prone, non-homologous end-joining (NHEJ), which occurs in the absence of any donor DNA. We have shifted the balance of DNA repair to the precise HDR pathway, and away from NHEJ, by formulating novel nuclease containing materials and selection strategies. The shift to more precise editing is demonstrated at genetic loci involving retinopathies, immune checkpoint genes, and at safe harbour loci for transgene integration. Gene variants, from single point mutations to multiple kilobase transgenes, can be precisely edited using these strategies. Noise of gene-editing is minimized by increasing rates of precise editing, thereby enabling the more precise methods of writing specific sequences into genomes. 

Research Interests

The Saha lab works to develop new human stem cell models and therapies using novel biomaterials and genetic engineering techniques. The lab is at the Wisconsin Institute for Discovery (WID) and uses synergy within our BIONAnocomposite Tissue Engineering Scaffolds theme at the WID. We are now funded by the NIH, NSF and EPA to perform high-impact research on pluripotent stem cells, regenerative medicine, disease modeling and synthetic biology. We have developed a wide array of engineering approaches that seek to generate new cells, organoids and tissues from patient samples, as well as a suite of gene-editing technologies to knockout, correct or insert transgenes into human cells.

Author Listing

Krishanu Saha (1,2); Jared Carslon-Stevermer (1,2); Benjamin Steyer (2); Nicole Piscopo (1,2); Amr Abdeen (2); Madelyn Goedland (2); Lucille Kohlenberg (2); Meng Lou (2); Evan Cory (2); Stephanie Steltzer (2); Katie Mueller (2); Amritava Das (2); Christian Capitini (3); David Beebe (1)

Affiliation

University of Wisconsin-Madison

All Author Affiliations

Biomedical Engineering, University of Wisconsin-Madison (1); Wisconsin Institute for Discovery, University of Wisconsin-Madison (2); Hematology and Oncology, University of Wisconsin-Madison (3)