This work was supported by NEI R21EY033941 (to Hongli Wu); Department of Defense W81XWH2010896 (to Hongli Wu); R15GM123463-02 (to Kayla Green and Hongli Wu)

All animal experiments were performed in accordance with the Association for Research in Vision and Ophthalmology guidelines for the Use of Animals in Ophthalmic and Vision Research. Procedural approval was granted by the University of North Texas Health Science Center Animal Care and Use Committee (protocol number: IACUC-2022-0008). Young C57BL/6J mice, typically under 2 weeks of age, were used in these studies.
1. Culture medium preparation and lens dissection
<ol>
	<li>Pr...

Cultivation and Characterization of Lens Epithelial Cells

<ol>
	<li>Bermbach, G., Mayer, U., Naumann, G. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+lens+epithelial+cells+in+tissue+culture.">Human lens epithelial cells in tissue culture.</a> Experimental Eye Research. 52 (2), 113-119 (1991).</li><li>Reddy, V. N., Lin, L. R., Arita, T., Zigler, J. S., Huang, Q. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystallins+and+their+synthesis+in+human+lens+epithelial+cells+in+tissue+culture.">Crystallins and their synthesis in human lens epithelial cells in tissue culture.</a> Experimental Eye Research. 47 (3), 465-478 (1988).</li><li>Lee, C. M., Afshari, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+global+state+of+cataract+blindness.">The global state of cataract blindness.</a> Current Opinion in Ophthalmology. 28 (1), 98-103 (2017).</li><li>Khairallah, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Number+of+people+blind+or+visually+impaired+by+cataract+worldwide+and+in+world+regions,+1990+to+2010.">Number of people blind or visually impaired by cataract worldwide and in world regions, 1990 to 2010.</a> Investigative Ophthalmology &amp; Visual Science. 56 (11), 6762-6769 (2015).</li><li>Beebe, D. C., Holekamp, N. M., Shui, Y. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oxidative+damage+and+the+prevention+of+age-related+cataracts.">Oxidative damage and the prevention of age-related cataracts.</a> Ophthalmic Research. 44 (3), 155-165 (2010).</li><li>Lou, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Redox+regulation+in+the+lens.">Redox regulation in the lens.</a> Progress in Retinal and Eye Research. 22 (5), 657-682 (2003).</li><li>Charakidas, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lens+epithelial+apoptosis+and+cell+proliferation+in+human+age-related+cortical+cataract.">Lens epithelial apoptosis and cell proliferation in human age-related cortical cataract.</a> European Journal of Ophthalmology. 15 (2), 213-220 (2005).</li><li>Lou, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glutathione+and+glutaredoxin+in+redox+regulation+and+cell+signaling+of+the+lens.">Glutathione and glutaredoxin in redox regulation and cell signaling of the lens.</a> Antioxidants (Basel). 11 (10), 1973 (2022).</li><li>Wilhelm, J., Smistik, Z., Mahelkova, G., Vytasek, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Redox+regulation+of+proliferation+of+lens+epithelial+cells+in+culture.">Redox regulation of proliferation of lens epithelial cells in culture.</a> Cell Biochemistry &amp; Function. 25 (3), 317-321 (2007).</li><li>Zhang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Research+progress+concerning+a+novel+intraocular+lens+for+the+prevention+of+posterior+capsular+opacification.">Research progress concerning a novel intraocular lens for the prevention of posterior capsular opacification.</a> Pharmaceutics. 14 (7), 1343 (2022).</li><li>Konopinska, J., Mlynarczyk, M., Dmuchowska, D. A., Obuchowska, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Posterior+capsule+opacification:+A+review+of+experimental+studies.">Posterior capsule opacification: A review of experimental studies.</a> Journal of Clinical Medicine. 10 (13), 2847 (2021).</li><li>Pandey, S. K., Apple, D. J., Werner, L., Maloof, A. J., Milverton, E. 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G., Trevithick, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differentiation+of+rat+lens+epithelial+cells+in+tissue+culture--iv.+Some+characteristics+of+the+process,+including+possible+in+vitro+models+for+pathogenic+processes+in+cataractogenesis.">Differentiation of rat lens epithelial cells in tissue culture--iv. Some characteristics of the process, including possible in vitro models for pathogenic processes in cataractogenesis.</a> Vision Research. 21 (1), 25-35 (1981).</li><li>Creighton, M. O., Mousa, G. Y., Trevithick, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differentiation+of+rat+lens+epithelial+cells+in+tissue+culture.+(i)+effects+of+cell+density,+medium+and+embryonic+age+of+initial+culture.">Differentiation of rat lens epithelial cells in tissue culture. (i) effects of cell density, medium and embryonic age of initial culture.</a> Differentiation. 6 (3), 155-167 (1976).</li><li>Ibaraki, N., Ohara, K., Shimizu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Explant+culture+of+human+lens+epithelial+cells+from+senile+cataract+patients.">Explant culture of human lens epithelial cells from senile cataract patients.</a> Japanese Journal of Ophthalmology. 37 (3), 310-317 (1993).</li><li>Sundelin, K., Petersen, A., Soltanpour, Y., Zetterberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+growth+of+lens+epithelial+cells+from+cataract+patients+-+association+with+possible+risk+factors+for+posterior+capsule+opacification.">In vitro growth of lens epithelial cells from cataract patients - association with possible risk factors for posterior capsule opacification.</a> The Open Ophthalmology Journal. 8, 19-23 (2014).</li><li>Parreno, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methodologies+to+unlock+the+molecular+expression+and+cellular+structure+of+ocular+lens+epithelial+cells.">Methodologies to unlock the molecular expression and cellular structure of ocular lens epithelial cells.</a> Frontiers in Cell and Developmental Biology. 10, 983178 (2022).</li><li>Andjelic, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+and+proliferative+studies+on+ex+vivo+cultured+human+anterior+lens+epithelial+cells+-+relevance+to+capsular+opacification.">Morphological and proliferative studies on ex vivo cultured human anterior lens epithelial cells - relevance to capsular opacification.</a> Acta Ophthalmologica. 93 (6), e499-e506 (2015).</li><li>Andjelic, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+method+for+establishing+adherent+ex+vivo+explant+cultures+from+human+eye+pathologies+for+use+in+subsequent+calcium+imaging+and+inflammatory+studies.">A simple method for establishing adherent ex vivo explant cultures from human eye pathologies for use in subsequent calcium imaging and inflammatory studies.</a> Journal of Immunology Research. 2014, 232659 (2014).</li><li>Andley, U. P., Rhim, J. S., Chylack, L. T., Fleming, T. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Propagation+and+immortalization+of+human+lens+epithelial+cells+in+culture.">Propagation and immortalization of human lens epithelial cells in culture.</a> Investigative Ophthalmology &amp; Visual Science. 35 (7), 3094-3102 (1994).</li><li>Zhou, M., Leiberman, J., Xu, J., Lavker, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hierarchy+of+proliferative+cells+exists+in+mouse+lens+epithelium:+Implications+for+lens+maintenance.">A hierarchy of proliferative cells exists in mouse lens epithelium: Implications for lens maintenance.</a> Investigative Ophthalmology &amp; Visual Science. 47 (7), 2997-3003 (2006).</li><li>Wolffe, A. P., Glover, J. F., Tata, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culture+shock.+Synthesis+of+heat-shock-like+proteins+in+fresh+primary+cell+cultures.">Culture shock. Synthesis of heat-shock-like proteins in fresh primary cell cultures.</a> Experimental Cell Research. 154 (2), 581-590 (1984).</li><li>Haykin, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioimage+analysis+of+cell+physiology+of+primary+lens+epithelial+cells+from+diabetic+and+non-diabetic+cataract+patients.">Bioimage analysis of cell physiology of primary lens epithelial cells from diabetic and non-diabetic cataract patients.</a> Biotechnology &amp; Biotechnological Equipment. 35 (1), 170-178 (2021).</li><li>Menko, A. S., Klukas, K. A., Johnson, R. 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The protocol presented in this paper provides a comprehensive, step-by-step guide to the successful isolation, culture, and subculture of primary LECs, complete with accompanying video documentation. The detailed visual guide alongside the written instructions enhances the clarity and accessibility of the protocol, promoting its use and reproducibility among researchers in the field. The ultimate aim is to contribute to the expanding body of knowledge surrounding the role of LECs in cataract formation and PCO, a prevalen...

The lens of the eye plays a crucial role in vision by focusing incoming light onto the retina. It consists of a transparent, avascular structure composed of specialized cells, among which lens epithelial cells (LECs) are key players. LECs are located at the anterior surface of the lens and are responsible for maintaining its transparency, regulating water balance, and participating in lens growth and development1,2. LECs are a unique type of cells located at the anterior part of the lens, playing a critical role in maintaining lens clarity and function by continuously producing lens fibers throughout life.
Cataracts are characterized by the progressive clouding of the lens, resulting in the distortion and scattering of light, leading to compromised vision3,4. The precise mechanisms underlying cataract formation are complex and multifactorial, involving various cellular and molecular processes such as UV radiation, oxidative damage, and glycation5,6. LECs have been found to contribute significantly to the development of cataracts, making them a vital focus of research1,2,7,8,9.
Furthermore, one of the most pressing issues in ophthalmology today is the relatively high incidence of posterior capsule opacification (PCO), also known as secondary cataract. PCO remains the most common complication after cataract surgery, affecting up to 20-40% of adult patients and 100% of children within 5 years post surgery10. PCO is primarily caused by the residual LECs that remain in the capsular bag following cataract extraction. These cells undergo a multifaceted pathophysiological transformation involving not only epithelial-to-mesenchymal transition (EMT) but also the differentiation of LECs to lens fibers, resulting in a cell population that is a mixture of LECs, fibers, and myofibroblasts11,12,13. The transformed cells proliferate and migrate across the posterior lens capsule, leading to visual impairment. Understanding the behavior and control mechanisms of LECs in culture models can provide valuable insights into the prevention and management of PCO. Therefore, this protocol of culturing LECs presents a vital tool for ophthalmic researchers aiming to study, understand, and ultimately combat this prevalent postoperative complication.
To unravel the intricacies of LEC biology and its role in cataract formation and PCO, it is essential to establish robust and reproducible in vitro primary cell culture systems. Primary LEC culture provides researchers with a controlled environment to study the functions, signaling, and molecular characteristics of LECs. Furthermore, it allows for the investigation of cellular processes and the effects of different experimental conditions, providing valuable insights into lens physiology and pathology.
Prior research has enriched our understanding of LEC culture techniques14,15,16,17,18,19,20. Although these studies have employed various methodologies and yielded significant findings on LEC behavior and characteristics, a comprehensive and accessible video recording protocol for culturing LECs is absent in the current literature. This limitation can hinder novice researchers&#39; ability to accurately reproduce the techniques and can lead to inconsistencies and variations in experimental results. By providing a video recording protocol, this research paper aims to bridge this gap and provide a standardized resource that can enhance reproducibility and facilitate knowledge transfer in the field of LEC culture.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.05% Trypsin-EDTA</td>
			<td>Thermo Fisher</td>
			<td>#25300054</td>
			<td>For LECs dissociation</td>
		</tr>
		<tr>
			<td>Alexa Fluor 488 Secondary Antibody&#160;</td>
			<td>Jackson ImmunoResearch</td>
			<td>#715-545-150</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Alexa Fluor 647 AffiniPure Goat Anti-Rabbit IgG (H+L)</td>
			<td>Jackson ImmunoResearch</td>
			<td>111-605-003</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Antibody dilution buffer</td>
			<td>Licor</td>
			<td>#927-60001</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Beaver safety knife</td>
			<td>Beaver-Visitec International</td>
			<td>#3782235</td>
			<td>For lens dissection</td>
		</tr>
		<tr>
			<td>Blocking buffer</td>
			<td>Licor</td>
			<td>#927-60001</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Capsulorhexis forceps</td>
			<td>Titan Medical Instruments</td>
			<td>TMF-124</td>
			<td>For lens capsule isolation</td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Sigma Aldrich</td>
			<td>D6429</td>
			<td>For LECs culture medium</td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sigma Aldrich</td>
			<td>#D2650</td>
			<td>For making freezing medium&#160;</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Phosphate Buffered Saline&#160;</td>
			<td>Thermo Fisher</td>
			<td>#J67802</td>
			<td>For lens dissection</td>
		</tr>
		<tr>
			<td>Dumont tweezers</td>
			<td>Roboz Surgical Instrument</td>
			<td>RS-4976</td>
			<td>For lens capsule isolation</td>
		</tr>
		<tr>
			<td>EpiCGS-a (optional)</td>
			<td>ScienCell</td>
			<td>4182</td>
			<td>For LECs culture medium</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Sigma Aldrich</td>
			<td>F2442</td>
			<td>For LECs culture medium</td>
		</tr>
		<tr>
			<td>Gentamicin (50&#160;mg/mL)</td>
			<td>Sigma-Aldrich</td>
			<td>G1397</td>
			<td>For LECs culture medium</td>
		</tr>
		<tr>
			<td>Hoechst 33342 solution</td>
			<td>Thermo Fisher</td>
			<td>#62249</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Micro-dissecting scissors</td>
			<td>Roboz Surgical Instrument&#160;</td>
			<td>RS-5983</td>
			<td>For lens dissection</td>
		</tr>
		<tr>
			<td>Micro-dissecting tweezers</td>
			<td>Roboz Surgical Instrument&#160;</td>
			<td>RS5137&#160;</td>
			<td>For lens dissection</td>
		</tr>
		<tr>
			<td>PROX1 antibody</td>
			<td>Thermo Fisher</td>
			<td>11067-2-AP</td>
			<td>For cell validation</td>
		</tr>
		<tr>
			<td>Vannas micro-dissecting spring scissors</td>
			<td>Roboz Surgical Instrument</td>
			<td>RS-5608</td>
			<td>For lens capsule isolation</td>
		</tr>
		<tr>
			<td>&#945;A-crystallin antibody</td>
			<td>Santa Cruz</td>
			<td>sc-28306</td>
			<td>For cell validation&#160;</td>
		</tr>
		<tr>
			<td>&#947;-crystallin antibody</td>
			<td>Santa Cruz</td>
			<td>sc-365256</td>
			<td>For cell validation</td>
		</tr>
	</tbody>
</table>

optimizing mouse primary lens epithelial cell culture: a comprehensive guide to trypsinization

Lens epithelial cells (LECs) play multiple important roles in maintaining the homeostasis and normal function of the lens. LECs determine lens growth, development, size, and transparency. Conversely, dysfunctional LECs can lead to cataract formation and posterior capsule opacification (PCO). Consequently, establishing a robust primary LEC culture system is important to researchers engaged in lens development, biochemistry, cataract therapeutics, and PCO prevention. However, cultivating primary LECs has long presented challenges due to their limited availability, slow proliferation rate, and delicate nature. 
This study addresses these hurdles by presenting a comprehensive protocol for primary LEC culture. The protocol encompasses essential steps such as the formulation of an optimized culture medium, precise isolation of lens capsules, trypsinization techniques, subculture procedures, harvest protocols, and guidelines for storage and shipment. Throughout the culture process, cell morphology was monitored using phase-contrast microscopy. 
To confirm the authenticity of the cultured LECs, immunofluorescence assays were conducted to detect the presence and subcellular distribution of critical lens proteins, namely &#945;A- and &#947;-crystallins. This detailed protocol equips researchers with a valuable resource for cultivating and characterizing primary LECs, enabling advancements in our comprehension of lens biology and the development of therapeutic strategies for lens-related disorders.

Author Spotlight: Unlocking the Secrets of Cataracts &#8211; Investigating Redox Repair Enzymes in Lens Epithelial Cells

Optimizing Mouse Primary Lens Epithelial Cell Culture: A Comprehensive Guide to Trypsinization

Our research objective is to explore the underlying causes of cataracts with a particular emphasis on the function of redox repair enzymes. Our aim is to identify the critical role this enzyme play in lens protection, and to establish their potential as drug targets for cataract prevention and treatment. Among many exciting technologies, our research uses lens epithelial cells as a foundational platform.This approach is critical for unraveling the mechanism behind cataract formation, posterior capsule opacification, and the discovery of new anti-cataract drugs. Moving forward, we will focus on understanding the impact of antioxidant enzymes and aging on lens functionality. Our goal is to discover innovative antioxidant treatments that can delay lens aging, prevent cataracts, and provide effective intervention for PCO.

As shown in Figure 2, by following this protocol, primary LECs from C57BL/6J mice adhered to the dishes within a period of 4 h. Notably, there were visible remnants of other tissues such as sections of the posterior capsule and lens fiber cells. However, these unintended elements did not attach to the dish and could, therefore, be removed by changing the culture medium. Subsequently, between the third and fifth day, the LECs initiated their proliferation phase. Rapid growth, characteristic o...

This manuscript outlines a detailed video protocol for culturing primary lens epithelial cells (LECs), aiming to improve reproducibility and aid research in cataracts and posterior capsule opacification (PCO). It offers step-by-step instructions on lens dissection, LECs isolation, and validation, serving as a valuable guide, especially for newcomers in the field.

Lens epithelial cells (LECs) play multiple important roles in maintaining the homeostasis and normal function of the lens. LECs determine lens growth, ...