In vitro responses of primed rabbit lymph node cells to myoglobin and its synthetic antigenic peptides: production of macrophage inhibitory factor and antibody to myoglobin

Antigenic domains of the sperm-specific lactate dehydrogenase C4 isozyme

Lactate dehydrogenase C4 (LDH-C4) is an antigenic protein that occurs only in spermatozoa and the mature testis. The antibody-combining sites of this enzyme were mapped by measuring the binding of anti-LDH-C4 by isolated peptides. Pure mouse LDH-C4 was digested with trypsin, and the resulting fragments were fractionated by reverse-phase high-pressure liquid chromatography. Rabbit anti-mouse LDH-C4 bound to 13 pure peptides. Amino acid compositions and partial or complete sequencing by the Edman degradation was used to identify eight of these fragments in the complete structure of the molecule. The relationship between structure and antigenicity of these peptides is discussed in detail. These data fit best to the domain model of protein antigenicity. This antigenic map of LDH-C4 will be useful in the design of a synthetic contraceptive vaccine.

Depressed in vitro and in vivo antibody response and adoptive transfer of delayed hypersensitivity to myoglobin with spleen cells of mice chronically infected with Schistosoma japonicum and injected with myoglobin

Spleen cells from C57BL/6J mice infected for 21 weeks with Schistosoma japonicum did not show an in vitro secondary antibody response upon challenge with sperm whale myoglobin. Mice infected for 13 weeks showed almost no in vivo secondary antibody response to this antigen. Spleen cells from mice infected for 12 to 21 weeks did not adoptively transfer delayed hypersensitivity to this antigen.