Macro Text - Bold? Italics? Highlight? Colors?

Is it possible, within a macro, to have any text that is bolded , italicized , highlighted, or a different color? If not, is it possible to have any text highlighted yellow, as numbers are when they are inline with brackets?

Kristin C. said: Presently there's no way to affect the text format in the chat window. Not entirely true. sendChat from the API can use the /direct command to incorporate HTML, including bold, italics, etc. Admittedly, that's only possible from the API. My Critical Hit script makes use of this to display new inline rolls. (span class="basicdiceroll", class="inlinerollresult showtip tipsy-n", and the classes fullfail, fullcrit, and importantroll)

Thank you for the responses :)