Five things to know: Silk innovation, a tech lease, Biogen R&D and the Best Places to Work

Good morning, Boston. Here are the five things you need to know in local business news to start your busy Wednesday.Eli Chavez reports that a lab at Tufts University is working with one of the oldest and most domesticated animals on the planet: silkworms. You won't believe what their silk can be used for.Greg Ryan reports that marketing tech company Klaviyo is expanding its Boston headquarters, at a time when many others in the tech sector have cut back on office space.Hundreds of law…