Expanding the clinical and immunological phenotypes of COPB1 deficiency

Our findings expand the clinical and immunological spectrum of COPB1 deficiency, demonstrating combined immunodeficiency with neutropenia, lymphopenia and impaired specific antibody responses. These results support the classification of COPB1 deficiency as a combined immunodeficiency with syndromic features under the IUIS classification system and emphasize the importance of comprehensive immunological evaluation and early immunoglobulin replacement therapy in patients with <i>COPB1</i> mutations.