Forcing MSTest to use a single thread

I solved this problem with locking:

public static class IntegrationTestsSynchronization
{
    public static readonly object LockObject = new object();
}

[TestClass]
public class ATestCaseClass
{
    [TestInitialize]
    public void TestInitialize()
    {
        Monitor.Enter(IntegrationTestsSynchronization.LockObject);
    }

    [TestCleanup]
    public void TestCleanup()
    {
        Monitor.Exit(IntegrationTestsSynchronization.LockObject);
    }

    //test methods
}

// possibly other test cases

This can of course be extracted to a base test class and reused.