An ELISA procedure for detecting human anti-endotoxin antibodies in serum

We report an ELISA method suitable for the large-scale screening of blood bank stores to identify those blood units containing high concentrations of antiendotoxin antibodies. In Natal, 8.3% of total units collected had antiendotoxin antibodies at concentrations greater than 40 micrograms/ml, values that may be therapeutically useful. We found that one technician could screen enough samples per year to produce 800 litres of such high-titre plasma.