Premacular Cell Proliferation Profiles in Tangential Traction Vitreo-Maculopathies Suggest a Key Role for Hyalocytes

Abstract

<b><i>Purpose:</i></b> To compare immunocytochemical and ultrastructural features of premacular tissue surgically removed from eyes with tangential traction vitreo-maculopathies. <b><i>Methods:</i></b> By spectral-domain optical coherence tomography (SD-OCT), premacular tissue was differentiated into premacular proliferation and premacular membrane (PMM). Specimens were harvested during vitrectomy from 10 eyes with macular pucker, lamellar macular hole (LMH) and full-thickness macular hole, and prepared for immunocytochemistry and transmission electron microscopy. <b><i>Results:</i></b> All specimens showed positive autofluorescence consistent with the yellow colour of peeled tissue. Glial cells were predominantly positive in premacular proliferation. Hyalocytes were the main cell type in PMM. Electron microscopy revealed densely packed premacular glial cells neighbouring hyalocytes and vitreous collagen strands. Myofibroblasts with features indicative of contractile properties were found in PMM, exclusively. Cell composition of premacular proliferation was free of contractile elements. <b><i>Conclusion:</i></b> All three types of vitreo-maculopathy have similar cell constituents in their premacular tissue. Cell population of premacular proliferation is not unique for LMHs. Corresponding to SD-OCT, electron microscopy demonstrates hyalocytes and vitreous collagen in PMMs both directly adjacent to the cellular complex of premacular proliferation. Study results point to the vitreous as one important pathogenic player potentially driving the degenerative cellular process at the vitreoretinal interface in tangential traction vitreo-maculopathies.

Identification of epiretinal proliferation in various retinal diseases and vitreoretinal interface disorders

“…In their study, they reported hyporeflective proliferation in 19 out of 3291 eyes with ERM. Consistently, co-existence of both ERM and ERP has been demonstrated by Schuman and co-workers [9]. Using SD-OCT imaging and ultrastructural analysis, they noticed presence of both tissues with close proximity in a two-layer complex, in different vitreoretinal pathologies.…”

“…Conversely, idiopathic ERM consists mainly of hyalocytes, fibroblasts and myofibroblasts, which explain their tractional properties. Macroscopically, ERP had a yellow appearance when in the foveal area, which may be explained by the presence of xanthophyll pigments, as demonstrated by Obana and colleagues [ 9 , 11 ]. This reinforces the suggestion that Müller cells are the main constituent of ERP, and that it originates from the retinal tissue [ 12 ].…”

“…This suggests that different signals may trigger this proliferative process [10]. Histological studies in LMH have reported that ERP consists of retinal glial cells, specifically Müller cells, and lacks myofibroblasts [5,9]. Conversely, idiopathic ERM consists mainly of hyalocytes, fibroblasts and myofibroblasts, which explain their tractional properties.…”

The Changes of Serum Lipids in Idiopathic Epiretinal Macular Membranes

“…Using immunocytochemistry and transmission electron microscopy, hyalocytes and vitreous collagen have been observed in the cellular complex of premacular membrane. It is suggested that hyalocytes play a key role for the formation of premacular membrane [12,13]. The correlation between hyalocytes and serum lipids remains incompletely understood.…”

Stellungnahme von BVA, DOG und RG zur Entwicklung, Diagnostik und Behandlung der epiretinalen Gliose

“…Der dadurch bedingte Verbleib von Glaskörperkollagen und Hyalozyten auf der vitrealen Seite der ILM wird Vitreoschisis genannt [121]. Nach aktuellen Erkenntnissen begünstigen Anteile der Glaskörperrinde eine weitere Ansiedelung von Zellen und somit die Ausbildung epiretinaler Membranen [118].…”