私は答えを見つけました、以下のコードを見てください:
// retrieving IVsTextManager and highlight id
DTE2 applicationObject = ...; // get it during addin init
Microsoft.VisualStudio.OLE.Interop.IServiceProvider serviceProvider = (Microsoft.VisualStudio.OLE.Interop.IServiceProvider)applicationObject;
Guid SID = typeof(SVsTextManager).GUID;
Guid IID = typeof(IVsTextManager).GUID;
IntPtr output;
serviceProvider.QueryService(ref SID, ref IID, out output);
IVsTextManager textManager = (IVsTextManager)Marshal.GetObjectForIUnknown(output);
int highlightID;
Guid highlightGuid = ...; // your highlighted text style guid
textManager.GetRegisteredMarkerTypeID(ref highlightGuid, out highlightID);
// highlighting text block in the active view
IVsTextView view;
int result = textManager.GetActiveView(0, null, out view);
IVsTextLines buffer;
view.GetBuffer(out buffer);
buffer.CreateLineMarker(highlightID, startLine, startColumn, endLine, endColumn, null, null);
その他の例は、MetaScroll VisualStudioAddinにあります。