St. Luke's-Roosevelt: J. Bhattacharya
City College Collaborators: S. Weinbaum, D. Rumschitzki

We have developed the first digital imaging approach for in situ studies of cell biology in the blood-perfused lung. In studies that were published in highly competitive, peer-reviewed journals, we reported dynamic quantifications of the intracellular calcium concentration, receptor expression, and exocytosis rates in single cells of the capillary and alveolar membranes. These studies have revealed: (i) lung capillaries contain calcium wave-generating, pacemaker endothelial cells at branch-points; (ii) high vascular pressure causes pacemaker cell-initiated proinflammatory events; (iii) the innate immune defense mechanism includes proinflammatory signalling between alveolar epithelial and capillary endothelial cells; (iv) intercellular communication regulates secretion by alveolar type II epithelial cells.

In new directions, we will develop imaging by confocal microscopy to define stress-induced cell signalling at different planes of focus to define cell-cell interactions in the regulation of organ function. The NIH (NHLBI) has continuously supported this research since 1980. Current support includes three RO1s and a MERIT award from the NIH.