Transformation is preceded by the appearance of
subcolumnar reserve cells, initially as a single layer.
Algunas especies carecen de este nectario y poseen, en esa posicion, un pistilodio emergente de origen carpelar (Pozner, 1993), glanduliforme, hemiesferico o
subcolumnar, libre de la pared del hipanto (por ejemplo, A.
Cytokeratin (CK) 17 is found in subcolumnar reserve cells, and immature metaplastic squamous epithelium, but not in columnar endocervical cells and squamous epithelium.
CK17 was normally expressed in the cytoplasm of the subcolumnar reserve cell layer and immature squamous metaplasia (Figure 3, A), but not in the apically located mucin-containing columnar epithelium and mature, or atrophic, squamous epithelia.
(171-173) Furthermore, characteristic features of microglandular hyperplasia include: (1) frequent reported association (but not always) with a history of hormone therapy or pregnancy; (2) presentation as an incidental finding; (3) superficial location; (4) cells frequently with subnuclear or supranuclear vacuoles; (5) small uniform nuclei with inconspicuous nucleoli; (6) absent to rare mitotic figures; and (7) focal squamous metaplasia and
subcolumnar reserve cell hyperplasia.