The progression of an immune response can be thoroughly studied in the blood thanks to the ease of drawing the fluid from animals and humans. But “it’s becoming increasingly clear that tissue-level responses don’t look like blood-level responses,” says immunologist Sarah Fortune of the Harvard T.H. Chan School of Public Health. “And we haven’t had very good ways to monitor tissue responses.”
A researcher could examine an immune response in, for example, the skin by taking a punch biopsy, which is invasive, or by measuring redness and swelling, which reveals nothing about the cells and factors involved in the response.
But new microneedle patches devised by MIT’s Darrell Irvine and colleagues provide information about the cellular response without having to remove tissue for analysis.
The patches measure approximately 1 cm2, contain an array of roughly 80 solid polymer microneedles (each one around 250 µm2 at its base and 500–600 µm ...
