Tabotamp®, Respectively, Surgicel®, Increases the Cell Death of Neuronal and Glial Cells In Vitro

Abstract

Oxidized regenerated cellulose (ORC) is an approved absorbable hemostat in neurosurgery, and contains 18–21% carboxylic acid groups. This modification leads to a low pH in aqueous solutions. Therefore, the aim of study was to analyze the pH-dependent effects of the ORC Tabotamp® on astrocytes, Schwann cells, and neuronal cells in vitro to investigate whether Tabotamp® is a suitable hemostat in cerebral eloquent areas. The ORC-dependent pH value changes were measured with (i) a pH meter, (ii) electron paramagnetic resonance spectroscopy, using pH-sensitive spin probes, and (iii) with fluorescence microscopy. Cell lines from neurons, astrocytes, and Schwann cells, as well as primary astrocytes were incubated with increasing areas of Tabotamp®. Cytotoxicity was detected using a fluorescence labeled DNA-binding dye. In addition, the wounding extent was analyzed via crystal violet staining of cell layers. The strongest pH reduction (to 2.2) was shown in phosphate buffered saline, whereas culture medium and cerebrospinal fluid demonstrated a higher buffer capacity during Tabotamp® incubation. In addition, we could detect a distance-dependent pH gradient by fluorescence microscopy. Incubation of Tabotamp® on cell monolayers led to detachment of covered cells and showed increased cytotoxicity in all tested cell lines and primary cells depending on the covered area. These in vitro results indicate that Tabotamp® may not be a suitable hemostat in cerebral eloquent areas.