B-hSIRPA/hCD47,Prkdc/Il2rg KO mice

Basic Information

Strain Name
C57BL/6-Sirpatm1(SIRPA)Cd47tm1(CD47)Prkdctm1Il2rgtm1/Bcgen
Stock Number
140739
Common Name
B-hSIRPA/hCD47,Prkdc/Il2rg KO mice
Source/Investigator
Bcgen (Beijing Biocytogen Co., Ltd)
Related Genes
SIRPA: BIT, CD172A, MFR, MYD-1, P84, PTPNS1, SHPS1, SIRP; CD47: IAP, MER6, OA3; Prkdc: scid; Il2rg: CD132, [g]c, gamm, gamma(, gamma(c), gc, p64
Species
C57BL/6
Appearance
Black
Genotypes
Homozygous

Description

Signal regulatory protein α (SIRPα) is a transmembrane protein with an extracellular region comprising three Ig-like domains and a cytoplasmic region containing immunoreceptor tyrosine-based inhibition motifs which mediate binding of the protein tyrosine phosphatases SHP1 and SHP2. SIRPα is especially abundant in myeloid cells such as macrophages and dendritic cells(DC), whereas it is expressed at very low levels in T, B ,NK, and NK T cells. SIRPα inhibits phagocytosis in macrophages upon interacting with its ligand CD47, which is commonly upregulated on the surface of malignant cells. Thus, antibodies that block the CD47-SIRPα interaction should enhance macrophage phagocytosis in the tumor microenvironment and inhibit tumor growth, making anti-SIRPα antibodies promising tools for cancer immunotherapy. Biocytogen has developed the B-hSIRPA/hCD47,Prkdc/Il2rg KO mice. The genes of Prkcd and Il2rg were knocked out, while the mouse extracellular domain of Sirpa and CD47 genes were replaced with the extracellular domain of human Sirpa and CD47 genes. So these mice completely lack mature T, B and NK cells and were deficient in cytokine signaling, but express the extracellular domain of human SIRPA and CD47.

Details

Protein expression analysis

Species specific SIRPα and CD47 expression analysis in B-hSIRPA/hCD47,Prkdc/Il2rg KO mice by flow cytometry. Splenocytes isolated from C57BL/6 (+/+) mice and homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice (H/H) were analyzed by flow cytometry with anti-SIRPα and anti-CD47 antibodies. Human SIRPα and CD47 were exclusively detectable in homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice but not in C57BL/6 mice. Mouse SIRPα was detectable in C57BL/6 and homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice, indicating that this anti-mouse SIRPα antibody was cross-reacting with human SIRPα.

Species specific SIRPα and CD47 expression analysis in B-hSIRPA/hCD47,Prkdc/Il2rg KO mice by flow cytometry. Splenocytes were isolated from C57BL/6 (+/+) mice and homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice (H/H) stimulated with anti-mCD3ε in vivo and were analyzed by flow cytometry with anti-SIRPα and anti-CD47 antibodies. Human SIRPα and CD47 were exclusively detectable in homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice but not in C57BL/6 mice. Mouse SIRPα was detectable in C57BL/6 mice and homozygous B-hSIRPA/hCD47,Prkdc/Il2rg KO mice, indicating that this anti-mouse SIRPα antibody was cross-reacting with human SIRPα.

Analysis of leukocyte subpopulations in spleen

Analysis of leukocyte subpopulations in spleen by FACS 

 Splenocytes were isolated from C57BL/6, B-NDG mice and B-hSIRPA/hCD47,Prkdc/Il2rg KO mice (n=3, 11-week-old). Flow cytometry analysis of the splenocytes was performed to assess leukocyte subpopulations. Single live cells were gated for CD45 population and used for further analysis as indicated here. T, B and NK cells were undetectable in B-NDG mice and B-hSIRPA/hCD47,Prkdc/Il2rg KO mice.

Analysis of leukocyte subpopulations in spleen

Analysis of leukocyte subpopulations in spleen by FACS

Splenocytes were isolated from C57BL/6, B-NDG mice and B-hSIRPA/hCD47,Prkdc/Il2rg KO mice (n=3, 11-week-old). Flow cytometry analysis of the splenocytes was performed to assess leukocyte subpopulations. Single live cells were gated for CD45 population and used for further analysis as indicated here. T, B and NK cells were undetectable in B-NDG mice and B-hSIRPA/hCD47,Prkdc/Il2rg KO mice.