人類巨細胞病毒是造成免疫不全者感染的主要原因，當被人類巨細胞病毒感染時，細胞內許多參與去氧核醣核苷酸複製的蛋白質會大量的表現。增生細胞核抗原在去氧核醣核苷酸複製過程中扮演著關鍵性的角色，因此為探討細胞在遭受到人類巨細胞病毒感染後，增生細胞核抗原是否也會大量表現？我們觀察被人類巨細胞病毒感染的細胞中增生細胞核抗原的蛋白質、核醣核苷酸及啟動子的活性是否上升。實驗結果發現，在被人類巨細胞病毒感染後，增生細胞核抗原的蛋白質、核醣核苷酸量增加，啟動子的活性也上升，由此可以顯示人類巨細胞病毒可以經由調控基因的轉錄來增加增生細胞核抗原的表現；我們也經由發現病毒的立即早期蛋白質1能夠活化增生細胞核抗原的啟動子而驗證了此項假設。此外我們也發現，在受到人類巨細胞病毒感染後，增生細胞核抗原在細胞核內會呈現顆粒狀，且和病毒聚合酶輔助因子及立即早期蛋白質2位於細胞核內同樣的位置。因此細胞在受到人類巨細胞病毒感染後，增生細胞核抗原的表現會被病毒的立即早期蛋白質1活化，而增生細胞核抗原蛋白質會被帶到病毒的去氧核醣核苷酸複製的位置。由此現象我們提出一個假設，病毒可能是需要增生細胞核抗原參與病毒的去氧核醣核苷酸複製。

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