Sheep erythrocytes ingested by guinea pig peritoneal macrophages in vitro, and permitted to undergo digestion for various periods, were found after some hours to lose the capacity to induce antibodies while gaining the ability to invoke delayed hypersensitivity. These observations may be related to the known predilection of small molecular immunogens to act as good inducers of delayed reactivit...

Cutaneous hypersensitivity responses to brucella antigens of different composition were studied in guinea pigs sensitized by infection with smooth brucella or immunization with killed rough brucella in adjuvant. These animals had circulating antibodies to smooth lipopolysaccharide or protein antigens, respectively. Intradermal skin tests, active cutaneous anaphylaxis, passive cutaneous anaphyl...

We describe a patient who developed a delayed-type hypersensitivity reaction to piperacillin/tazobactam in the cement beads and a spacer inserted at revision of total replacement of the left knee. We believe that this is the first report of such a problem. Our experience suggests that a delayed-type hypersensitivity reaction should be considered when a mixture of antibiotics such as piperacilli...

A soluble material has been isolated from schistosome eggs which in minute quantities without the addition of adjuvant induces sensitization to a delayed hypersensitivity type of granuloma forming around intact schistosome eggs. This material is secreted by intact eggs and is found in high concentration in the fluid released during the hatching process. When adsorbed to bentonite particles this...

BCG cell wall skeletons (SK) derived from BCG cell walls (CW) by treatment with proteolytic enzymes and organic solvents were tested for their potency to cause regression of a transplanted guinea pig hepatoma. On a weight basic, SK were as effective as CW in causing tumor regression, and they, as well as purified protein derivative of mycobacteria, provoked delayed cutaneous hypersensitivity re...

BCG cell wall skeletons (SK) derived from BCG cell walls (CW) by treatment with proteolytic enzymes and organic solvents were tested for their potency to cause regression of a transplanted guinea pig hepatoma. On a weight basis, SK were as effective as CW in causing tumor regression, and they, as well as purified protein derivative of mycobacteria, provoked delayed cutaneous hypersensitivity re...