title: Patterns of reaggregation and formation of linear aggregate chains in collagen-well cultures of dissociated mouse brain and spinal cord cells.
abstract: With the use of the newly developed collagen-well culture technique spontaneous reaggregation of cells from dissociated embryonic mouse brain and spinal cord were studied. Within 20 h in culture, aggregates are formed and settled onto collagen substrate. Two patterns of aggregate arrangement were observed; random and linear. Linear chains of aggregates appeared to be more characteristic of dissociated spinal cord cells, although the linear patterns were not uncommon in cultures of dissociated cortex. Formation of aggregate chains appeared to be dependent on the stage of neuronal and glial differentiation. After attachment to the collagen substrate, the general pattern of aggregate organization was not greatly altered except for changes which resulted from cellular migration and proliferation, the formation of connections between aggregates, or incorporation of small aggregates into larger ones. The number of non-aggregated cells in collagen-well cultures was small. Single, non-aggregated neurons seldom survived individually. Fiber connections between aggregates began to form after the first day in vitro, and by 2 or 3 days, the growing fibers formed neuritic bridges connecting aggregates. By the end of the first week growing fibers often organized compact bundles, but part connections between aggregates were presented by separate fibers in a diffused manner. Silver impregnation revealed that these connections were formed by the axons of neurons located in the aggregates. Thus, progression of the above described processes resulted in the de' novo' formation of linear organized or random systems of interconnected neuronal centers.
mesh_terms: D000818:Animals; D002449:Cell Aggregation; D002454:Cell Differentiation; D002465:Cell Movement; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology*; D003094:Collagen; D051379:Mice; D008810:Mice, Inbred C57BL; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000166:cytology; D013116:Spinal Cord / Q000166:cytology*
chemical_list: D003094:Collagen