Polychlorinated biphenyl (PCB) 126 or PCB 169 was administered to pregnant rats and kinetic changes in plasma protein spots of their next generation (F2 rats) ages 1, 3, 6, and 15 weeks were observed by micro two-dimensional polyacrylamide gel electrophoresis (M2D-PAGE).
In the control group in which age-related changes were observable, changes in the form of the albumin (Alb) spot were recognized at ages 1-3 weeks. Only the Alb spot on the acid side, i.e., non-mercaptoalbumin, was recognized at age 1 week. At age 3 weeks, the Alb spot on the alkaline side, i.e., mercaptoalbumin, also became observable. On the other hand, qualitative changes in the form of Alb, i.e., manifestations of mercaptoalbumin, were recognized at age 1 week by administration of PCB 126. This result suggested that the influence of PCB 126 on the living body is greater than that of PCB 169. In spite of the treatment for toxicity by equivalence of dose control on the basis of toxicity equivalency factor (TEF) 0.1 for PCB 126 (PeCB) and 0.01 for PCB 169 (HxCB), the influence of PCB 126 on the living body was greater than that of PCB 169.
The C3 spot was increased at age 3 weeks in the PCB 126 and the PCB 169. The spot showed a tendency toward increase at age 6 weeks in the PCB 126. The TEF compared PCB169 with PCB126, and distinctly increase of the C3 spot was observed for 15 weeks though the TEF was low. From these, as for the PCB 169, it was suggested appearing remarkably in aging influence of the immunity toxicity.
The observations of the changes in these spots led to the conclusion that the changes in these spots resulted from transfer of the drugs accumulating in the maternal body to the F2 rats of the maternal rats administered PCB 126 and those administered PCB 169 via the breast milk and that these changes are involved with inflammatory proteins, including the target genes influenced by the toxicity of coplanar PCBs.

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We have developed a technique, which can produce high-density protein chips. In this technique, proteins are separated by gel electrophoresis, and electroblotted by semidry blotting apparatus onto a diamond-like carbon-coated stainless-steel plate (DLC plate) of which surface is modified chemically with amino groups. Proteins immobilized on this protein chip can interact with other proteins in solution, and proteins interacted with the immobilized proteins can be identified by mass spectrometric analysis. However, the electroblotting efficiency was not stable. We anticipated that the unstable efficiency might be related to the fluctuation of temperature during electroblotting. In the present study, to investigate the optimal temperature for efficient and effective electroblotting, we developed a semidry blotting apparatus, which could regulate blotting temperature from 4 to 45°C (±1°C). The high and reproducible blotting efficiency was obtained at not low temperature but rather high temperature (30°C). The temperature did not impede protein identification or analysis of protein-protein interactions on the DLC plates by mass spectrometry.

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A silkworm (Bombyx mori) proteome database (SPD) was constructed using Make-2DDB II software. The present SPD contains the proteomes of the seven major tissues in the silkworm: the middle silkglands, posterior silkglands, midguts, fat bodies, hemolymph, ovaries, and Malpighian tubules. Proteins in each tissue at day 3 of the fifth instar were identified by MS/MS analysis and the protein profiles by 2-DE from day 1 of the fourth instar larva to the adult moth were constructed.

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