Use the Caption property to specify the item's caption. Use the <img> HTML tag to insert icons inside the item's caption. 

The Caption property supports built-in HTML tags like follows:

• <b>  bold </b>
• <u> underline </u>
• <s> strikeout </s>
• <i> italic </i>
• <fgcolor = FF0000> fgcolor </fgcolor>
• <bgcolor = FF0000> bgcolor </bgcolor>
• <br> breaks a line. 
• <solidline> draws a solid line
• <dotline> draws a dotted line
• <upline> draws the line to the top of the text line
• <r> aligns the rest of the text line to the right side
• <img>number[:width]</img> inserts an icon inside the cell's caption. The number indicates the index of the icon being inserted. The last 7 bits in the high significant byte of the number expression indicates the identifier of the skin being used to paint the object. Use the Add method to add new skins to the control. If you need to remove the skin appearance from a part of the control you need to reset the last 7 bits in the high significant byte of the color being applied to the part. The width is optional and indicates the width of the icon being inserted. Using the width option you can overwrite multiple icons getting a nice effect. By default, if the width field is missing, the width is 18 pixels.
• <img>key[:width]</img> inserts a custom size picture being loaded using the HTMLPicture property. The Key parameter indicates the key of the picture being displayed. The Width parameter indicates a custom size, if you require to stretch the picture, else the original size of the picture is used.
• <font face;size>text </font> displays portions of text with a different font and/or different size. For instance, the <font Tahoma;12>bit</font> draws the bit text using the Tahoma font, on size 12 pt. If the name of the font is missing, and instead size is present, the current font is used with a different size. For instance, <font ;12>bit</font> displays the bit text using the current font, but with a different size.
• <a id;options> anchor </a>, specifies hyperlinks in your text. An anchor is a piece of text or some other object (for example an image) which marks the beginning and/or the end of a hypertext link.The <A> element is used to mark that piece of text (or inline image), and to give its hypertextual relationship to other documents. The control fires the AnchorClick event when the user clicks an anchor element. Use the FormatAnchor property to specify the visual effect for anchor elements. For instance, if the user clicks the anchor <a1>anchor</a>, the control fires the AnchorClick event, where the AnchorID parameter is 1, and the Options parameter is empty. Also, if the user clicks the anchor <a 1;yourextradata>anchor</a>, the AnchorID parameter of the AnchorClick event is 1, and the Options parameter is "yourextradata". Use the AnchorFromPoint property to retrieve the identifier of the anchor element from the cursor. Use the ShowToolTip method to display a custom tooltip.

You can pass set the item's caption when adding the item using the Add method. Use the Bold property to specify whether or not the item should appear n bold. Use the Image, Picture properties to assign icons or pictures to your item.