The B6-hIgA1 mouse is a humanized model constructed by inserting the human IGHA1 gene sequence into the region between the mouse IgM enhancer (Eμ) and IgM constant region (Cμ), replacing the mouse IgM switch region (Sμ). B6-hIgA1 mice successfully express the human IGHA1 gene, and high levels of human IgA1 protein can be detected in their serum. Therefore, B6-hIgA1 mice can be used to study B cell development, immunoglobulin formation, and autoimmune mechanisms. They can also be crossed with CD89 humanized mouse models (catalog number: C001563) to create IgA nephropathy (IgAN) mouse model that better reflect human genetic mechanisms and pathological phenotypes [4], facilitating the development of IgA1-targeted drugs.