A single-column amino acid analysis method which resolves hexosamines and several cysteine derivatives.

A single-column amino acid analysis method is presented for use in structural studies of glycoproteins. The system gives excellent resolution of glucosamine, galactosamine, cysteic acid, CM-cysteine, AE-cysteine, the internal standard norleucine, and all amino acids normally present in protein hydrolysates.

Selective suppression of delayed hypersensitivity by the induction of immunologic tolerance.

Administration of DNP-BGG to newborn guinea pigs resulted, in more than half of the animals, in the specific suppression of delayed hypersensitivity to DNP-BGG and BGG, as shown after immunization with DNP-BGG in complete Freund's adjuvant. In contrast, all animals formed antibodies to DNP-BGG, whether or not delayed hypersensitivity to this antigen was present. No difference in antibody titers was found between pretreated and control animals.

EFFECT OF 6-MERCAPTOPURINE (6-MP) ON DIFFERENT CLASSES OF ANTIBODY.

In the primary response of mice and rabbits immunized with foreign red cells, 6-MP administration prolonged the formation of 19S antibody. 7S antibody formation was delayed and reduced in these animals. Animals treated with 6-MP during primary response exhibited a preferential 19S response when challenged in the anamnestic response.