The potential of label-free nonlinear optical molecular microscopy to non-invasively characterize the viability of engineered human tissue constructs.
Nonlinear optical molecular imaging and quantitative analytic methods were developed to non-invasively assess the viability of tissue-engineered constructs manufactured from primary human cells. Label-free optical measures of local tissue structure and biochemistry characterized morphologic and functional differences between controls and stressed constructs. Rigorous statistical analysis accounted for variability between human patients. Fluorescence intensity-based spatial assessment and metabolic sensing differentiated controls from thermally-stressed and from metabolically-stressed constructs. Fluorescence lifetime-based sensing differentiated controls from thermally-stressed constructs. Unlike traditional histological (found to be generally reliable, but destructive) and biochemical (non-invasive, but found to be unreliable) tissue analyses, label-free optical assessments had the advantages of being both non-invasive and reliable. Thus, such optical measures could serve as reliable manufacturing release criteria for cell-based tissue-engineered constructs prior to human implantation, thereby addressing a critical regulatory need in regenerative medicine.
Department of Biomedical Engineering, University of Michigan College of Engineering & Medical School, 1101 Beal Avenue, Ann Arbor, MI 48109-2110, USA. Electronic address: lengleng@umich.edu.
Leng-Chun
LC
Chen
Department of Biomedical Engineering, University of Michigan College of Engineering & Medical School, 1101 Beal Avenue, Ann Arbor, MI 48109-2110, USA. Electronic address: billlloy@umich.edu.
William R
WR
Lloyd
Department of Oral and Maxillofacial Surgery, University of Michigan School of Dentistry, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA. Electronic address: skuo@med.umich.edu.
Shiuhyang
S
Kuo
Center for Statistical Consultation and Research, University of Michigan School of Public Health, 915 E. Washington, Ann Arbor, MI 48109-1070, USA. Electronic address: myrakim@umich.edu.
Hyungjin Myra
HM
Kim
Department of Surgery, University of Michigan Medical School, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA. Electronic address: cmarcelo@umich.edu.
Cynthia L
CL
Marcelo
Department of Oral and Maxillofacial Surgery, University of Michigan School of Dentistry, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA; Department of Surgery, University of Michigan Medical School, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA. Electronic address: sefein@med.umich.edu.
Stephen E
SE
Feinberg
Department of Biomedical Engineering, University of Michigan College of Engineering & Medical School, 1101 Beal Avenue, Ann Arbor, MI 48109-2110, USA. Electronic address: mycek@umich.edu.
Mary-Ann
MA
Mycek
D002454:Cell Differentiation; D002470:Cell Survival; D003430:Cross-Sectional Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D015603:Keratinocytes / Q000737:chemistry; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D009061:Mouth Mucosa / Q000737:chemistry / Q000166:cytology; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry
Fluorescence lifetime imaging microscopy (FLIM); Label-free optical molecular imaging; Multiphoton excitation microscopy; Second-harmonic generation (SHG) imaging; Tissue engineering; Tissue viability