> ## Documentation Index > Fetch the complete documentation index at: https://docs.adaptyvbio.com/llms.txt > Use this file to discover all available pages before exploring further. # Target Proteins > We can work with nearly any soluble protein target that is commercially available, or we can custom express proteins for you. Browse our target catalog for an overview of available targets. If you need a custom or proprietary target, we can help source and prepare the appropriate materials. We focus primarily on soluble protein targets and maintain a curated list of readily available antigens to simplify project initiation. For custom or proprietary targets, we can work with you to source and prepare the appropriate materials. While we currently do not support membrane proteins or full-length IgGs, we can often accommodate binding domains derived from these more complex systems. Browse available targets in our catalog: targets.adaptyvbio.com.