How to use a wildcard-containing SUMIF function in VBA?

I would like to put the following functions in the cells of a given column if someone clicks on the button of a userform:

=IF(A3<>"";SUMIF(Items!$A:$A;"*"&Summary!$A:$A&"*";Items!$E:$E);"")

Should I go for an If and Then structure or create a user defined function?

And how could I express that (especially the wildcard part)?

'add gross value
Dim j As Integer
Dim Count As Double
Dim Item As Object

Count = WorksheetFunction.CountA(Sheets("Items"), Range("E:E"))

For j = 3 To Count
  For Each Item In Sheets("Summary").Cells(j, 1)
       If Sheets("Summary").Cells(j, 1) = Sheets("Items").Cells(j, 1) Then
       'besoin de définir la fonction somme
       Sum Sheets("Items").Cells(j, 5)
       
       End If
   Next
   
 Next

End Sub