FIG. 3.

Megakaryocyte migration, adhesion, and proplatelet formation. Mature megakaryocytes were stained with an anti CD61 antibody and added to each well of the bioreactor. (A) The silk microtubes were coated with 300 ng/mL SDF-1α and a combination of Matrigel with FBG and vWF or Matrigel alone or type I collagen, as controls. Prestained megakaryocytes were then added to each bioreactor and megakaryocyte migration toward the vascular microtubes was analyzed. After 16 h megakaryocyte migration through the gel composed of Matrigel+FBG+vWF was significantly higher compared with other conditions. (B) Z-stack projection (i) of megakaryocytes in adhesion to the surface of the silk microtube well after 24 h incubation with orthogonal projections in the z–y (ii) and x–z (iii) directions to confirm cell adhesion in tube cross-sections. (C) After an additional 16 h, megakaryocytes extended proplatelets through the vascular microtube wall as shown in the orthogonal projections of a proplatelet (green) protruding into the vascular tube (gray). Color images available online at www.liebertonline.com/tec