R&D Systems, a Bio-Techne Brand's Sheep IgG Alexa Fluor® 488-conjugated Antibody is a Sheep Polyclonal antibody. This antibody has been shown to work in applications such as: Other. The Sheep IgG Alexa Fluor® 488-conjugated Antibody was generated using IGHG1, and immunoglobulin heavy constant gamma 1 (G1m marker) as the antigen and it reacts with Sheep.