strip_tags

index.php:

$smarty = new Smarty;
$smarty->assign('articleTitle', "Blind Woman Gets <font face=\"helvetica\">New Kidney</font> from Dad she Hasn't Seen in <b>years</b>.");
$smarty->display('index.tpl');

index.tpl:

{$articleTitle}
{$articleTitle|strip_tags}

OUTPUT:

Blind Woman Gets <font face="helvetica">New Kidney</font> from Dad she Hasn't Seen in <b>years</b>.
Blind Woman Gets New Kidney from Dad she Hasn't Seen in years.