Conditioned medium from activated spleen cells supports the survival of rat retinal cells in vitro

Abstract

Cytokines are a heterogeneous group of molecules that have been associated with several functions in the nervous system, such as survival and differentiation of neuronal and glial cells. In the present study, we demonstrated that conditioned medium from spleen cells activated with concanavalin A increased neuritogenesis and survival of retinal cells, as measured by biochemical and morphological criteria. Our data showed that conditioned medium induced a five-fold increase in the amount of protein after 120 h in vitro. This effect was not inhibited by the blockade of voltage-dependent L-type calcium channels with 5.0 µM nifedipine. However, the use of an intracellular calcium chelator (15.0 µM BAPTA-AM) inhibited this effect. Our results support the idea that factors secreted by activated lymphocytes, such as cytokines, can modulate the maintenance and the differentiation of rat retinal cells in vitro, indicating a possible role of these molecules in the development of retinal cells, as well as in its protection against pathological conditions.

Effect of Spleen-Cell-Conditioned Medium on [³H]-Choline Uptake by Retinal Cells in vitro Is Mediated by IL-2

“…Spleen Cell Culture SCM was obtained using procedures previously described [15]. Briefly, adult Lister hooded rats were killed by ether asphyxia, the spleens were removed, and single-cell suspensions were prepared by passing the spleens through a sterile 50-gauge plastic mesh in CMF solution.…”

“…On the other hand, an increase in cytoplasmic calcium levels was shown to be essential for the effect of SCM, since BAPTA-AM (15 ÌM ), an intracellular calcium chelator, was efficient in blocking the increase in protein level [15]. In addition to these data, table 3 shows that the effect of SCM after 120 h was not inhibited either by dantrolene (30 ÌM) or by tetrodotoxin (1 ÌM), indicating that neither ryanodine-sensitive calcium channels nor voltagedependent sodium channels are involved in the action of SCM.…”

“…To study the effect of different cytokines on retinal cells, we previously analyzed the effect of conditioned medium from concanavalin A (conA)-stimulated splenocytes (SCM) on neuronal and glial cell survival [15]. SCM was chosen because it contains a broad spectrum of molecules, including growth-promoting factors such as colonystimulating factors, interleukins and a nerve growth factor (NGF)-related molecule [16][17][18].…”

“…SCM was chosen because it contains a broad spectrum of molecules, including growth-promoting factors such as colonystimulating factors, interleukins and a nerve growth factor (NGF)-related molecule [16][17][18]. Our previous data demonstrated that SCM increases the survival of retinal cells in vitro and that this effect was mediated by an increase in the cytoplasmic calcium level [15]. In the present study, we investigated the effect of SCM on the cholinergic differentiation of retinal cells in culture.…”

Medium requirements for neuritic outgrowth from goldfish retinal explants and the trophic effect of taurine

“…Conditions of the culture include the addition of fetal calf serum (Landreth and Agranoff, 1979), since in the absence of it neuritic outgrowth is dramatically restricted, even in the presence of trophic molecules, such as taurine (Lima et al, 1988). There have been several approaches to solve the important issue of studying the influence of stimulating agents per se without the concomitant effect of several substances present in the serum (Caffe et al, 2001;Espinosa de los Monteros et al, 1997;Sholl-Franco and Araujo, 1997;Winkler et al, 2000).…”