33 gauge hamilton needle

Male and female mice at age seven to eight weeks were randomly assigned to the treatment groups. ONC injury was performed as described previously (Park et al., 2008 (link); Patel et al., 2017 (link)). The mice were anesthetized using an isoflurane mixture and one drop of 0.5% proparacaine hydrochloride was added to the eye. A small incision was made in the superior posterior area of the conjunctiva to expose the optic nerve. ONC was performed ∼1 mm behind the globe carefully avoiding blood vessels for 5 s with extra-fine self-closing forceps. The ONC eyes were intravitreally injected with recombinant Wnt5a (20 and 50 ng, in 2 μl; R&D Systems Inc) or the equivalent volume of sterile saline, using a 33-gauge Hamilton needle (Hamilton Company). Erythromycin ointment was topically applied to treat the injected eye and analgesia was provided with buprenorphine SR (0.5 mg/ml). Animals were excluded from the study if they had excessive bleeding or swelling at any time after the procedure.

All experiments involving mice were approved by the Animal Care and Use Committee at the University of Miami and were carried out in accordance with the ARVO statement for the Use of Animals in Ophthalmic and Vision research. The retinal degeneration 10 (rd10) mouse model was purchased from Jackson Laboratory and housed with a 12-h light–dark cycle, free access to food and water, and all cages were maintained at similar distances from the overhead lights. Experimental and control treatments were from the same litters.
Mice were divided randomly into experimental groups and were injected intravitreously with sterile saline (control) or IL-27 (10, 20, 40 ng/µl) (BioLegend, San Diego, CA) on post-natal day (P) 18, as follows. The mice were anesthetized using isoflurane, the corneas were anesthetized with a drop of 0.5% proparacaine hydrochloride and the mice were placed under a surgical microscope on a heated pad to maintain body temperature at 37 °C. The eyes were intravitreally injected with 1 µl of solution using a 33-gauge Hamilton needle (Hamilton Company, Reno, NV) passed through the sclera into the vitreous cavity and angled to avoid the lens. The fellow eye was uninjected. Mice with bleeding or swelling were excluded from further study. Investigators were masked to the treatment for all subsequent analyses.