Doublecortin cells and stroke

Abstract Introduction Doublecortin (DCX) is a microtubule associated protein expressed by migrating neural precursors. DCX is expressed in approximately 4% of all cortical cells in adult normal primate brain. DCX cells are is thought to play a role in plasticity or neural repair because their expression is enhanced locally in response to an acute insult made to the brain. That being said, it would be interesting to know how the expression of DCX is modified in stroke. The aim of my work is to study the expression of DCX cells in the cortex of patients having a stroke, compared to control patient. Methods DCX cells were quantified on DCX stained 5 μm thick formalin fixed paraffin embedded brain sections in 5 stroke patients and 3 control patients. . By using a computerized image analysis system (Explora Nova, La Rochelle, France), cortical areas were selected on injured and perilesional areas. Total number of cells was counted, whereall nuclei were colored in blue. Then the DCX cells were counted on the corresponding DCX sections. The ratio of DCX cells over total cells was then calculated. Results We observed a similar ratio of DCX cells/total cells in the patients who died 1 day, 25 days and 1460 days after their stroke and in the control patients. However we found an important increase of the ratio DCX/total cells in the patients who died 2 and 13 days after stroke. In these two patients, the maximal amount of DCX cells could be observed in the perilesional areas. Discussion and conclusion The increase of DCX cells ration in patients died 2 and 13 days after stroke could be due to DCX cells being more resistant to degeneration after ischemia compared to surrounding cells. or to a recrutment of DCX cells, either from the cortical source of DCX cells or from the stem cell sub ventricular zone. In order to be able to answer this question, the total number should be counted, which is methodologically challenging