for (int i = 0; i < 10; i++)
{
     Collection.Add(...);
     System.Threading.Thread.Sleep(2000);
}

Task task = new Task(() =>
{
      Метод, обновляющий данные
});
task.Start();

        private System.Windows.Forms.Integration.ElementHost hostWpfControl;

        private void MAIN_FORM_Load(object sender, EventArgs e)
        {
            hostWpfControl = new System.Windows.Forms.Integration.ElementHost();
            hostWpfControl.Dock = DockStyle.Fill;
            hostWpfControl.Parent = this;

            DesReportViewModel viewModel = new DesReportViewModel();

            DesReportView _desReportView = new DesReportView();

            // Когда ViewModel посылает запрос на закрытие - закрыть окно
            EventHandler handler = null;
            handler = delegate
            {
                viewModel.RequestClose -= handler;
                this.Close();
            };

            viewModel.RequestClose += handler;

            _desReportView.DataContext = viewModel;

            viewModel.ReportDate = DateTime.Today.Date;

            try
            {
                hostWpfControl.Child = _desReportView;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        }

    public static class DispatchService
    {
        public static Dispatcher DispatchObject { get; set; }

        public static void Dispatch(Action action)
        {
            if (DispatchObject == null || DispatchObject.CheckAccess())
            {
                action();
            }
            else
            {
                DispatchObject.Invoke(action);
            }
        }
    }

    {
        InitializeComponent();
        DispatchService.DispatchObject = this.Dispatcher;
    }

            DispatchService.Dispatch(() =>
            {
                Collection.Add(...);
            });