Ultrasound Biomicroscopy: A Powerful Tool Probing Murine Lymph Node Size in vivo

Abstract Invasive cell-counting in lymph node (LN) is the current reference to assess LN changes due to inflammation, immunodeficiency and cancer in murine models. This work evaluates whether ultrasound biomicroscopy (UBM) can measure LN size alterations noninvasively for a large range of sizes (0.1 mm 3 to 22 mm 3 ). Correlation was assessed ( ρ = 0.91, p 2 ). Reliability (intraclass correlation coefficient [ICC] > 0.84) and variability of UBM evaluations compared favourably with invasive cell count. UBM provides a noninvasive alternative to cell-counting in mice for early detection and longitudinal screening of LN modifications. This can enable significant reduction in the number of mice and exploration of LNs that would be too small to dissect for cell count. (E-mail: Lori.Bridal@upmc.fr or matteo.bosisio@gmail.com )