Dr. Singh will be joining Cornell University as an Assistant Professor in the Sibley School of Mechanical and Aerospace Engineering, effective July 2013. Dr. Singh joined the laboratory of Prof. Andres Garcia in the Woodruff School of Mechanical Engineering and Prof. Todd McDevitt in Whitaker School of Biomedical Engineering at Georgia Tech as a postdoctoral fellow in Feb 2010. Dr. Singh has considerable expertise in the engineering of biomaterials-based platforms for cell and immune modulation, cell adhesive forces, stem cell engineering, cell-biomaterial interactions, and analyses of cell adhesion. His research has established a new separation technique, called micro stem cell high-efficiency adhesion-based recovery (µSHEAR), that depends on an easily-distinguished physical difference in adhesive forces among cells could help expand production of stem cells generated through cell reprogramming. The separation process was described recently in the journal Nature Methods. Dr. Singh’s research has also established multi-modal, biomaterials-based vaccine to enhance the potency of lymphoma and hepatitis vaccines in small animal models and provided a foundation in bioengineering strategies to regulate cell behavior for therapeutic purposes. His work has been published in journals such as Nature Methods, Proc. Natl. Acad. Sci. USA, Molecular Therapy, J Cell Science, Biomaterials, J Controlled Release, Biomedical Microdevices, and Oligonucleotides. At Cornell University, Dr. Singh's "Immunotherapy and Cell Engineering Lab (ICEL)" will focus on understanding the role of cell biomechanics and mechanical signal transduction in human development and addressing key problems in curing diseases, like cancer, through application of innovative bioengineering approaches that control behaviors of cells.
Generation of human induced pluripotent stem cells (hiPSCs) from fibroblasts and other somatic cells using reprogramming factors represents a highly promising strategy to produce autologous cell sources for regenerative therapies as well as novel models of human development and disease. The reprogramming process is inefficient (0.001-2%) and hiPSC cultures are often heterogeneous because of the presence of undifferentiated stem cells, parental and partially reprogrammed cells, and spontaneously differentiated derivatives. The problem of non-specific cell contamination is also evident in routine hiPSC culture with recurring spontaneous differentiation ad directed differentiation protocols to generate specific lineages, such as neural progenitors and cardiomyocytes. The ability to efficiently isolate undifferentiated human pluripotent stem cells (hPSCs) as colonies from contaminating non-pluripotent cells is a crucial step in the stem cell field to maintain high survival efficiency and karyotypic stability of the hPSCs and relies primarily on time-intensive manual isolation based on morphological assessments or single cell sorting. We demonstrate significant differences in focal adhesion assembly and adhesion strength among undifferentiated hiPSC and parental/feeder layer cells, partially reprogrammed cells, spontaneously differentiated and directly differentiated progenitor cells. This distinct ‘adhesive signature’ of hiPSCs was exploited to rapidly (<10 min) and efficiently isolate fully reprogrammed ‘bona fide’ hiPSCs as intact colonies from partially reprogrammed cells, unreprogrammed parental cells, feeder layer cells, spontaneously differentiated cells, and terminally differentiated mature neurons and cardiomyocytes using microfluidics technology termed µSHEAR (micro Stem cell High-Efficiency Adhesion-based Recovery). hiPSCs, irrespective of source, passage number, and feeder-free matrix, were isolated in a label-free fashion and enriched to >95-99% purity and survival without adversely affecting the pluripotency, transcriptional profile, methylation patterns, differentiation potential or karyotype of the pluripotent cells. In addition, using µSHEAR, we demonstrate that TRA-1-60+ hiPSCs can be effectively detached within 5-7 minutes prior to the detachment of residual unreprogrammed or partially reprogrammed cells (TRA-1-60-negative). µSHEAR-isolated hiPSCs expressed all markers characteristic of bona fide hiPSCs, whereas residual cells expressed Oct4, hTERT, and GDF3 but not TRA-1-60, TRA-1-81, DNMT3B, REX1, SSEA-4, and NANOG. µSHEAR-isolated hiPSCs displayed unmethylated Oct4, SOX2 and NANOG, equivalent to the patterns in manually passaged hiPSCs. This low-cost, rapid, label-free, high-throughput strategy is applicable to isolate undifferentiated hiPSCs from heterogeneous reprogramming cultures and differentiating cell populations during routine hPSC culture and to remove undifferentiated stem cells from specific differentiated lineages, such as MAP2+β-III tubulin+ mature neurons and cardiomyocytes.
3rd International Conference on Stem Cell Engineering Travel Grant Award, Society for Biological Engineering - 3rd Intl. Conference on Stem Cell Engineering, Seattle, WA (2012)
Biomedical Engineering Society (BMES) Outstanding Graduate Research Award, BMES Annual Meeting, Pittsburgh, PA (2009)
Controlled Release Society (CRS) Student Travel Grant Award, CRS 36th Annual Meeting & Exposition, Copenhagen, Denmark (2009)
Professional Development Award by Office of The Vice Provost and Dean of Graduate Studies, The University of Texas at Austin (2009)
STAR Award, Society for Biomaterials: Translational Biomaterial Research Symposium, Atlanta, GA (2008)
Professional Development Award by Office of The Vice Provost and Dean of Graduate Studies, The University of Texas at Austin (2008)
Awarded MHRD-GATE Scholarship for outstanding achievements in academics by the Ministry of Human Resources Development (MHRD), Government of India (2004-2006)
