SIRPA (signal-regulatory protein alpha), strongly expressed in neurons and in macrophages, dendritic cells and neutrophils, is a transmembrane protein receptor that negatively regulates phagocytosis. Ligands CD47, surfactant A and surfactant D bind to the receptor, inducing the recruitment of phosphatases SHP1 and SHP2 to the plasma membrane, negatively regulating phagocytosis in phagocytic cells.

Introduction of the human SIRPA gene to 129-BALB genetic background mice carrying knockouts of Rag2 and Il2rg (T, B, and NK cell deficient - see Stock No. <a href="https://www.jax.org/strain/014593">014593</a>) significantly increased their ability to engraft and maintain human hematopoietic cells/progenitors in both the bone marrow and periphery. Levels of engraftment are comparable to those of NOD scid gamma (NSG) knockout mice (e.g. Stock No. <a href="https://www.jax.org/strain/005557">005557</a>) with the added benefit of increased lifespan and reduced host immune function/cytokine cross-reactivity. Increased antigen-specific humoral immune responses have been observed in these mice, suggesting potential applications in human vaccine development.

This humanized SIRPA (signal-regulatory protein alpha), Rag2, Il2rg, compound mutant strain is a useful immunodeficient model for improved human hematopoietic cell engraftment with potential utility in human vaccine development.

Typically mice are recovered in 12-16 weeks. Contact Customer Service to place an order or for more information.

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