NRP1 and Tooth abscess: The expression of ACE2, TMPRSS2, and NRP-1 was notably decreased in oral periapical lesions (such as periapical abscesses, preapical granulomas, and radicular cysts) when compared to healthy pulp tissues [82], and in periapical abscesses and granulomas, a negative correlation between IL6 and the gene expression of ACE2, NRP1, and TMPRSS2 was documented.