Question int.Parse not respecting CultureInfo

I've been having some issues parsing numbers with the "he-IL" (hebrew) CultureInfo and found out some strange situations.
This doesn't work in Unity:

Code (CSharp):

1. System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("he-IL");
2. int.Parse("+26", System.Globalization.CultureInfo.InvariantCulture);

But it works with C# REPL:

Code (CSharp):

1. csharp> System.Threading.Thread.CurrentThread.CurrentCulture;
2. he-IL                                                                                                                                                
3. csharp> int.Parse("+26", System.Globalization.CultureInfo.InvariantCulture;
4. 26

So I'm kinda lost here, it seems that the int.Parse while running in Unity is ignoring the culture parameter, at least for this locale.