There are many investigators who have studied the effects of inhibiting and promoting factors on tissue growth, and their tissue speciscities. Roberts & White have studied promoting factors in the thymus gland extract of cattle, and reported that these factors had tissue specificities. Kim, Lee & Suk also reported that inhibiting factors extracted from rat liver by Chin´s method, had tissue specificities. Butenandt, in his experimental study of the precipitation test, and the complement-fixation test with the microsomal fraction isolated from rat liver as an antigen, demonstrated the presence of tissue specific antigenic substances respectively in normal and neoplastic tissue. Author used the microsomal fractions isolated from fat liver and human stomach as an antigen, and investigated the specific reactivity of the fractions in normal and neoplastic through the precipitation test. And also studied the specific reactivity with the nuclear fractions isolated from the same organs.
Meterials and Methods.
The microsomal fractions and nuclear fractions were extracted from the liver and kidney of normal and DAB administered rat which had been given 5 ㎎. DAB daily, for four weeks. and from the normal human stomach and stomach cancer, as follows:
The extracts of the organs were homogenized in a Waring blendor, and centrifuged in a model PRI international centrifuge at 2,000 r.p.m. for 20 minutes. The supernatant was centrifuged at 15,000 r.p.m. for 45 minutes, and the obtained supernatant was used as the microsomal fraction. The sediment obtained after being centrifuged at 2,000 r.p.m. for 20 minutes was perilled by washing and centrifugation 8 times, and the last sediment was used as the nuclear fraction. Prior to the immunization, the microsomal fraction was standardized to contain 0.01-0.1 ㎎ Nitrogen／ml of the microsomal fraction and the nuclear fraction, to contain 0.1 ㎎ Nitrogen／ml. With 16 rabbits weighing about 2 ㎏. each, as one group, 2.0 ㏄ of the fractions was injected into the marginal ear vein of each rabbit every other day 9 times. 7 days after the last injection of the fractions the antibody titre was examined. When the antibody titre had reached a satisfactory level, the rabbit was bled from the heart and the antiserum was isolated. In order to remove the possible group reaction between the liver and kidney of the rat, the absorption was done, but it was not performed on the human stomach, as the human kidney from the same person was not available. Both the microsomal and nuclear fractions were standardized to contain 1-2 ㎎ Nitrogen／ml, and the precipitation test was done by applying the fractions to the antisera (Table 1, 2, 3 4, 5, 6, 7, 8.) And the characteristic reactivity of the fractions in normal rat liver and normal human stomach was compared with that in DAB administered rat liver and human stomach cancer. Readings were made as follows:
1. immediately after mixing in the test tube.
2. after 30 minutes in a Water bath at 37℃.
3. after 24 hrs. in a refrigerator at 4℃.
Recordings:
－ : no agglutinated material is present.
± : indefinite agglutinated material is present.
＋ : very small agglutinated material is present.
?? : small agglutinated material is present.
?? : medium-sized agglutinated material is present.
?? : large agglutinated material is· present.
?? : very large agglutinated matsrisl is present.
Results
1) It is considered that in the microsomal fractions, certain antigenic components of the normal rat liver or normal human stomach were not piesent in the DAB administered rat liver or human stomach cancer. In the same way, certain antigenic components of the DAB administered rat liver or human stomach cancer were not present in the normal rat liver or normal human stomach (Table 1, 2, 3, 4).
2) With the nuclear fractions as an antigen, similar results to the microsomal fractions were observed (Table 5, 6, 7. 8), and it is assumed, from this fact. that both the microsomal fraction and nuclear fraction in the normal or neoplastic tissue, have cer:tin antigenic components, specific for the tissue respectively.
3) Antigenicity of the nuclear fraction appeared to be not weaker than that of the microsomal fraction.
4) The irregular group reaction between the normal and neoplastic tissue cells was observed. In conclusion, the antiserum sensitized with the normal tissue cell component, showed a remarkable reaction selectively, when the same normal tissue cell component was applied. In the same way, the antiserum sensitized with the neoplastic tissue cell component, showed a remarkable reaction selectively, when the same neoplastic tissue cell component was applied and it is speculated that there are certain tissue specific components both in the normal and neoplastic tissue.
|