Rose-Hulman Undergraduate Research Publications

Document Type


Publication Date


First Advisor

William Weiner


The presence of endotoxins, a potentially life threatening bacterial contamination in medical devices and supplements, is determined by a product know as Limulus Amebocyte Lysate (LAL). The creation of LAL is known to raise the mortality rates of the crabs that are also seeing population declines due to environmental pressures and fishing industries. Because of the decline in the number of crabs, a method for the production of LAL, outside of the bleeding animals, is necessary. This research worked to quantify systematically the cell size, shape, and concentration of the amebocytes. After baseline data were collected, 40-50% of the hemolymph from six different animals was removed, and the recovery of the weight, amebocyte density, and diameter was regularly determined. Follow-up data showed the weight decreasing immediately after the large hemolymph removals, and recovery to baseline occurring within two weeks. Around day 8 after the large hemolymph removals, both the amebocyte density and diameter decrease. Between days 18 and 20 the density and diameter returned to normal, implying that new amebocytes can be seen in the hemolymph of a horseshoe crab about two weeks after a large hemolymph removal and the new cells will have a smaller diameter than the more mature amebocytes in the hemolymph.


RHURP 12-01