The somatic Sertoli cell of the testis provides structural and nutritional support to germ cells in the process of spermatogenesis. The specialized “nurse” functions of the Sertoli cell has been studied extensively in vitro since the first isolation and culture of primary cells in the 1970s.1-3
Various techniques to manipulate Sertoli cell gene expression, including transfection have been used,4,5
but the efficiency nor longevity of these methods is rarely reported as they do not lead to stable genomic integration.
Recently, adenovirus vectors have been used to transduce Sertoli cells in vivo,6,7
although low rates of transduction and cellular toxicity were noted. An alternative virus of the retroviridae
, possess the inherent capacity to transduce and stably integrate into non-dividing cells.8,9
Recently, retroviral transduction was used to overexpress a panel of neuronal transcription factors in proliferative phase Sertoli cells, directing the cells toward an induced neural stem/progenitor lineage.10
This study demonstrated the viability and potential use of retroviral vector transgene expression in primary juvenile Sertoli cells. Lentiviral based vectors have also been used to transduce Sertoli cells in an elegant in vivo study, in which the overexpression kit
ligand in c-kit
lignad null mice was able to restore fertility.6
Our laboratory has extensive experience in primary rat Sertoli cell culture as a model to study the regulation of cell junctions,11,12
growth factor signaling13
and gene expression,14
and we are currently utilizing a lentiviral based vector approach to manipulate Sertoli cell gene function in vitro. In early experiments, we noted that rat Sertoli cell monolayers were relatively inert to retroviral transduction. Herein, we describe a modified inoculation and centrifugation protocol (“spinoculation”),15,16
which considerably improves Sertoli cell transduction in vitro.