Phenotyping

Slit lamp imaging

Purpose

General ophthalmic observation to detect gross eye or eyelid defects (microphthalmia, eyelid closure, bulging eye, corneal opacities, lack of pupil response to changing light level...), followed by a detailed examination of the anterior segment of the eye (cornea, aqueous humor, lens, and vitreous) with a thin (slit) illumination, to better visualize anomalies in these transparent compartments. This test does not require anesthesia, as the anterior segment can be well-observed on vigil mice gently hand-held. Digital imaging can be obtained from anesthetized mice.

All images taken with TEFI (Nikon DSLR + 85 mm f/1.8 lens, coupled to an Hopkins endoscopic optic).

Equipment

SL-990 Slit Lamp (CSO, Firenze, Italy)

Micron IV with slit lamp extension (Phoenix Labs, Pleasanton, CA, USA)

Reference

Hyperactivation of Alk induces neonatal lethality in knock-in AlkF1178L mice. Lopez-Delisle L(1), Pierre-Eugène C, Bloch-Gallego E, Birling MC, Duband JL, Durand E, Bourgeois T, Matrot B, Sorg T, Huerre M, Meziane H, Roux MJ, Champy MF, Gallego J, Delattre O, Janoueix-Lerosey I. Oncotarget 2014 May 15;5(9):2703-13

Fundus imaging

Purpose

Fundus imaging allows detecting anomalies in retinal structure, pigmentation and/or vasculature, as occurring in various retinal diseases as retinitis pigmentosa (RP), glaucoma and other types of retinal degeneration.  This can be combined with OCT to help precise the localization of retinal lesions. In addition, the high sensitivity of the Micron III allows in vivo detection of fluorescent proteins or markers, for instance for longitudinal follow-up of cell populations expressing GFP or  RFP, or monitoring the efficacy of viral infection (gene therapy).

Equipment

Micron IV with GFP and RFP filters (Phoenix Labs, Pleasanton, CA, USA)

TEFI (Paques et al., IOVS 2007), which can be brought to other animal facilities if needed due to sanitary status of the animals.

References

A comparative phenotypic and genomic analysis of C57BL/6J and C57BL/6N mouse strains.Simon MM, Greenaway S, White JK, Fuchs H, Gailus-Durner V, Sorg T, Wong K, Bedu E, Cartwright EJ, Dacquin R, Djebali S, Estabel J, Graw J, Ingham NJ, Jackson IJ, Lengeling A, Mandillo S, Marvel J, Meziane H, Preitner F, Puk O, Roux M, Adams DJ, Atkins S, Ayadi A, Becker L, Blake A, Brooker D, Cater H, Champy MF, Combe R, Danecek P, di Fenza A, Gates H, Gerdin AK, Golini E, Hancock JM, Hans W, Hölter SM, Hough T, Jurdic P, Keane TM, Morgan H, Müller W, Neff F, Nicholson G, Pasche B, Roberson LA, Rozman J, Sanderson M, Santos L, Selloum M, Shannon C, Southwell A, Tocchini-Valentini GP, Vancollie VE, Wells S, Westerberg H, Wurst W, Zi M, Yalcin B, Ramirez-Solis R, Steel KP, Mallon AM, Hrab 283 de Angelis M, Herault Y, Brown SD.
Genome Biol 2013 Jul 31;14(7):R82

Mutations in lama1 disrupt retinal vascular development and inner limiting membrane formation. Edwards M.M., Mammadova-Bach E., Alpy F., Klein A., Hicks W.L., Roux M., Simon-Assmann P., Smith R.S., Orend G., Wu J., Peachey N.S., Naggert J.K., Lefebvre O., Nishina P.M. J Biol Chem 2010 Mar 5;285(10):7697-711

Retinoic acid receptor (RAR)-alpha is not critically required for mediating retinoic acid effects in the developing mouse retina. Cammas L., Trensz F., Jellali A., Ghyselinck N.B., Roux M.J., Dolle P. Invest Ophthalmol Vis Sci 2010 Jun;51(6):3281-90

Disease progression despite early loss of polyglutamine protein expression in SCA7 mouse model. Helmlinger D., Abou-Sleymane G., Yvert G., Rousseau S., Weber C., Trottier Y., Mandel J.L., Devys D. J Neurosci 2004 Feb 25;24(8):1881-7

Progressive retinal degeneration and dysfunction in R6 Huntington's disease mice. Helmlinger D, Yvert G, Picaud S, Merienne K, Sahel J, Mandel JL, Devys D. Hum Mol Genet 2002;15;11(26):3351-9

Angiography

Purpose

The injection of a fluorescent dye (fluorescein, Evans Blue) allows a detailed visualization of the retinal vasculature, even small capillaries, and the detection of vascular leakage and retinal edema.

Equipment

Micron IV (Phoenix Labs, Pleasanton, CA, USA)

Optical Coherence Tomography (OCT)

Purpose

Non invasive in vivo histology of the retina with 2-3 µm axial resolution, allowing precise thickness measurement of all retina layers, including photoreceptor segments. Sites (and size) of retinal lesions can thus be identified, and their evolution tracked over time, either to characterize a disease progression, of the efficacy of a pharmacological or gene therapy treatment.

Equipment

Bioptigen EnVisu R2200 (Bioptigen, Durham, NC, USA)

Electroretinogram

Purpose

Strain background references

Equipment

Siem Visiosystem (Siem Bio-Médicale, Nîmes, France)

References

Mutations in lama1 disrupt retinal vascular development and inner limiting membrane formation. Edwards M.M., Mammadova-Bach E., Alpy F., Klein A., Hicks W.L., Roux M., Simon-Assmann P., Smith R.S., Orend G., Wu J., Peachey N.S., Naggert J.K., Lefebvre O., Nishina P.M. J Biol Chem 2010 Mar 5;285(10):7697-711

Retinoic acid receptor (RAR)-alpha is not critically required for mediating retinoic acid effects in the developing mouse retina. Cammas L., Trensz F., Jellali A., Ghyselinck N.B., Roux M.J., Dolle P. Invest Ophthalmol Vis Sci 2010 Jun;51(6):3281-90

Disease progression despite early loss of polyglutamine protein expression in SCA7 mouse model. Helmlinger D., Abou-Sleymane G., Yvert G., Rousseau S., Weber C., Trottier Y., Mandel J.L., Devys D. J Neurosci 2004 Feb 25;24(8):1881-7

Progressive retinal degeneration and dysfunction in R6 Huntington's disease mice. Helmlinger D, Yvert G, Picaud S, Merienne K, Sahel J, Mandel JL, Devys D. Hum Mol Genet 2002;15;11(26):3351-9

Optomotor Response

The test is under improvement. We will used upgraded equipment to improve your phenotypic analysis experience !  See below the description of the older one.

Purpose

The optomotor test is based on the reflex tracking of moving objects in the visual field. While in humans this is achieved essentially through the optokinetic reflex, involving only eye movements, mice tend to follow moving objects through head movements, than can be easily visualized either in normal or low light conditions (with IR illumination). Mice are placed in the center of a rotating drum, which inside wall is covered with alternating black and white stripes, with spatial frequencies ranging from 0.03 to 1.25 cycles/degree (standard spatial frequency for first line testing is 0.26 cycle/degree). Head tracking of the bar movements is absent in blind animals. Visual acuity can be assessed by changing the bar spatial frequency. Absence of head tracking can have many origins. Notably albinos strains do not respond to the optomotor test, due to a defect in projections of the ganglion cells involved in this reflex.

Strain background references

Equipment

Reference

The optomotor response: a robust first-line visual screening method for mice. Abdeljalil Jellali, Hamid Méziane, Abdel-Mouttalib Ouagazzal, Stéphane Rousseau, Raymond Romand, Johan Auwerx, José Sahel, Pierre Chambon, Serge Picaud. Vision Res. 2005 May;45(11):1439-46.