Gata3 Insufficiency Accelerates Recanalization of Damaged Lymphatics via Adjusting Collagen Composition

The impaired repair of lymphatic vessels after tissue damage is an etiological hallmark of lymphedema. Previously, we demonstrated that lymphatic recanalization after the popliteal lymph node extirpation was delayed in Gata2 heterozygous mice. This impaired lymphatic vessel recanalization in Gata2 heterozygous mice was mitigated by administrating atelocollagen or crossing with heterozygous Gata3 deletion mice. To clarify the potential involvement of Gata3 heterozygosity in collagen gene expression within subdermal tissue, we conducted an RNAseq analysis and found 273 genes with up and 522 genes with down expression in Gata3 heterozygous mice, and these genes were categorized as collagen and extracellular matrix-related genes by GO analysis. We also found that Col6a1, a2, and a3, which compose type VI collagen, underwent a transient but significant upregulation during the lymphatic recanalization process. Histological analysis revealed that the collagen structure in the subdermal tissue exhibited thinner collagen fiber in Gata3 heterozygous deficient mice. These findings suggest that the altered collagen pattern in Gata3 heterozygous mice contributed to the enhanced lymphatic vessel recanalization in Gata2 heterozygous mice. The altered collagen expression pattern might play a role in shaping and maintaining the subcutaneous microenvironment.