Thank you for writing.
Depending on the binding scenario in most cases the grid should automatically reflect any changes to the data source. For example if you use a DataTable it will work out of the box, if you want to bind it to a collection of custom objects the custom object should implement the INotifyPropertyChanged interface and the collection should implement the IBindingList interface (you can use BindingList<T> which implements it internally).
More information about the available scenarios is available here: http://www.telerik.com/help/winforms/gridview-populating-with-data-databinding-radgridview.html
Let us know if you have any questions.
All the best,
the Telerik team