Die Immunabwehr, also die Abwehr eines Krankheitserregers oder Fremdkörpers mithilfe eine präzis(e) gesteuerten Abwehrsystems, ist eine der komplexesten Reaktionen im Körper eines Lebewesens.

The part in brackets was removed, and I am to fill it. I thought it was an adjective and put "en" but it's actually an adverb. In a previous question I asked, this sort of phenomena was explained through a difference in intended semantics refer, but I can't apply the principles there here. Could someone help?

I believe the main difficulty is that here adverb comes between noun and verb in a comma sentence which makes using the reasoning in above difficulter?

Die Immunabwehr, also die Abwehr eines Krankheitserregers oder Fremdkörpers mithilfe eines präzis(e) gesteuerten Abwehrsystems, ist eine der komplexesten Reaktionen im Körper eines Lebewesens.

The part in brackets was removed, and I am to fill it. I thought it was an adjective and put "en" but it's actually an adverb. In a previous question I asked, this sort of phenomena was explained through a difference in intended semantics refer, but I can't apply the principles there here. Could someone help?

I believe the main difficulty is that here adverb comes between noun and verb in a comma sentence which makes using the reasoning in above difficulter?