PubMed Health⌕ Search

Biomedical subjects

G Suhaciu

Publications and source records attributed to G Suhaciu.

At least 19 recordsLinked to original sources

A comparative study of the immunogenicity of some penicillins and of their cross reactions.

The immunogenicity of four penicillin preparations was comparatively investigated by titration of penicilloyl (PO) specific hemagglutinating antibodies found in sera of rabbits inoculated with equimolecular amounts of these penicillins incorporated in Freund incomplete adjuvant. Benzylpenicillin (BP) was shown to be endowed with the highest immunogenicity, while oxacillin (OX), ampicillin (AM) and Amoxil (AX) were found significantly less immunogenic. By examining comparatively the titers of hemagglutination reactions given by the sera of each animal with erythrocytes coated with the penicillin used for its immunization as well as with the other penicillins investigated, important cross immunological reactions were found in all of the cases. Interestingly, the cross reactions produced by AM- and AX-specific antisera with heterologous penicillins were apparently higher than the reactions obtained with the homologous penicillin. No significant differences were found concerning the ability of the four penicillins to form PO conjugates with BGG. Thus, the differences in immunogenicity exhibited by the four penicillin preparations may not be explained in this way.

Amoxicillin↗

Spontaneous formation of immunogenic conjugates by a biotransformation product of sulfanilamide.

3-hydroxy-sulfanilamide (3-HS) has been previously shown to be formed in significant amounts in rabbits and humans treated with sulfanilamide. In the present paper we demonstrate that 3-HS reacts readily with proteins at alkaline pH and forms conjugates capable to induce hapten specific antibodies in rabbits. According to our previous observations on ortho-aminophenol (OAP), the haptenic properties of 3-HS are apparently due to the presence in its molecule of an ortho-aminophenolic structure, rendering it capable to form a highly reactive quinoneimine derivative. In spite of a similar mechanism of linking and of the presence of an ortho-aminophenolic structure in the two haptens, 3-HS and OAP immunological systems do not cross react with each other. The data presented here support the hypothesis that 3-HS may represent the hapten or one of the haptens involved in sulfonamide allergy.

Animals↗

Immunological mechanisms in aspirin hypersensitivity. Studies on the immunogenicity of free aspirin.

Anti-aspiryl antibodies were produced in rabbits and guinea pigs by inoculation of aspirin incorporated in complete or incomplete Freund's adjuvant. These antibodies were readily detected by passive haemagglutination using rabbit erythrocytes incubated with aspirin at alkaline pH. Aspiryl conjugates with ovalbumin, human gamma-globulin, bovine gamma-globulin and rabbit serum were also prepared by incubating the proteins with aspirin at alkaline pH. Aspiryl conjugates prepared by this technique behaved, immunologically, identically with the conjugates prepared from aspirin chloride. By contrast, the molar absorbance at 305 nm of the conjugates prepared from aspirin was about 25 times lower than the molar absorbance of the conjugates prepared from aspirin chloride. Since the absorbance of salicylic acid is about eight times greater than that of aspirin, the conclusion is drawn that the aspiryl/salicylyl ratio is significantly higher in the conjugates prepared by incubating proteins with aspirin at alkaline pH than in the conjugates prepared from aspirin chloride. In parallel experiments, salicylic acid did not induce formation of specific antibodies capable of reacting with aspirin- or salicylic acid-treated red cells. Sera giving positive passive haemagglutination with aspirin-treated erythrocytes did not react with erythrocytes treated with salicylic acid or acetic anhydride.

Anhydrides↗