ABNORMAL LYMPHATIC PHENOTYPE IN A CRISPR MOUSE MODEL OF THE HUMAN LYMPHEDEMA-CAUSING CONNEXIN47 R260C POINT MUTATION

Connexin proteins form gap junctions controlling exchange of ions and small molecules between cells play an important role in movement lymph within lymphatic vessels. Connexin47 (CX47) is highly expressed endothelial CX47 missense mutations, i.e., R260C, cosegregate with primary lymphedema humans. However, studies utilizing knockout mice have failed to demonstrate any anomalies. To unravel the consequences expressing a mutant protein, we used CRISPR technology create mouse carrying Cx47 mutation (Cx47R259C) equivalent human CX47R260C associated lymphedema. Intradermal Evans Blue dye injection identified 2-fold increase regional nodes homozygous Cx47R259C compared wildtype, particularly jugular region (4.8 ± 0.4 2.0 0.0, respectively, p<0.01). Associated channels were increased mesenteric reflux occurred but not wildtype. Contractility superficial cervical lymphatics, assessed by pressure myography, was reduced In conclusion, our data are first for protein anatomy function. This phenotype similar that found other valve deficient mutants, e.g., Foxc2. Of significance, this study use develop pre-clinical model demonstrates importance distinguishing lack presence when developing clinically relevant animal models translation findings.