** Shares of companies developing Ebola vaccines rise beforethe bell
** Leading drugmakers plan to work together to acceleratedevelopment of an Ebola vaccine and produce millions of doses ofthe most effective experimental product for use next year
** Johnson & Johnson aims to produce at least 1million doses of its two-step vaccine next year and has alreadydiscussed collaboration with GlaxoSmithKline, which isworking on a rival vaccine
** GSK expects to have the first doses of its Ebola vaccineready late this year
** U.S.-listed shares of GSK up about 2 pct at$44.48
** J&J shares up 1.6 pct at $101.95, NewLink Genetics up 0.87 pct at $34.70
** Take A Look: World on alert to curb Ebola outbreak