Capture of LPS by the lobster blood clot1.

1LPS was added to freshly collected lobster blood at the concentrations indicated in column 1, then the blood was allowed to clot. After a 1 h incubation at 23°C, the serum was collected and diluted in LPS-free water as indicated in column 2 and assayed by the LAL test (column 3), as described in Materials and Methods. The sensitivity of the assay when LPS was added directly to cell-free lobster hemolymph was 0.1 ng/mL LPS, but due to the dilution of the experimental samples, the detection limit of the maximum concentration of free LPS remaining in solution in the serum was correspondingly elevated, as indicated in column 4. Subtraction of maximum free concentration of LPS from the initial concentration yields the minimum amount of LPS captured by the clot produced by 1 mL of lobster blood (column 5). Selected data points from this individual trial were replicated in 1 additional trial.