Interning at UPenn - how much will it improve chances?!

<p>I'm currently interning in one of the biomedical research labs at UPenn. How much do you think that improve my chances of getting into UPenn? I'm only a rising junior, but I'm pretty sure I'm applying ED when the time comes around. I plan on getting the doctor I am interning under to write me a letter of recommendation, if that helps significantly.</p>