NSG mice (NOD scid gamma, bred on a NOD/SCID genetic background) are severely immunocompromised, and the barrier practices that work fine for ordinary nude or scid colonies are not strict enough — routine pathogens that don't bother normal mice can wipe out an NSG cage.

The hack / solution

Switch to autoclaved or irradiated food, water, bedding, and pre-sterilized caging before anything enters an NSG cage, instead of the standard non-sterile supplies used for hardier strains. 2) Acidify drinking water to pH 2.5-3.0 to help prevent Pseudomonas infections. 3) House NSG mice in microisolator or pressurized individually ventilated cages, and change cages under a laminar flow hood, disinfecting the hood surface between each cage instead of between batches. 4) Handle mice with disinfected forceps or ethanol-sterilized gloves while wearing full sterile scrubs, mask, and hair covering — the glove-only handling used for less fragile immunodeficient strains isn't sufficient here. 5) In a standard, non-maximum-barrier research facility, change cages weekly instead of biweekly to keep pathogen buildup down.

📎Source: The Jackson Laboratory — Housing & Breeding for NSG Mice🔗View source🗓️Added: 2026-07-16✅Reviewed by: MouseStuff Admin