DISTRIBUTION OF IMMUNOGLOBULIN-CONTAINING CELLS AND LOCALIZATION OF SECRETORY COMPONENT IN GASTRIC MUCOSA BEARING CARCINOMA

Surgical materials of gastric carcinoma were studied immunohistochemically in terms of the distribution of immunoglobulin-containing cells and the localization of secretory component (SC). There was no convincing evidence suggesting that the secretory immune system surrounding carcinoma was responding to the carcinoma. But in some cases, increase of IgG-containing cells was observed in the stroma of carcinoma suggesting the presence of some kind of tumor immunity. In the non-carcinomatous mucosa, SC was observed strongly in cells of intestinal metaplasia except for the goblet cells, but weakly in the normal foveolar epithelium. The presence of SC in carcinoma cells was observed in 45 percent of the total cases of gastric carcinoma [36/80] and was especially porminent in signet-ring cell carcinoma [78%]. IgA was observed in about 50 percent of these SC-positive carcinoma cases. SC was also frequently positive in group III atypical epithelium

REGULATION OF PRIMARY ANTIBODY RESPONSE IN MICE BY TWO TYPES OF SUPPRESSOR CELLS RESISTANT TO ANTI-THY-1 SERUM TREATMENT

The anti-SRBC antibody response of normal young adult mice (about 3 months old) was specifically suppressed, when the spleen cells derived from the syngeneic donor mice that had been previously primed with a high dose of SRBC were adoptively transferred at the time of antigenic challenge. The suppression was antigen-specific and was mediated by a fraction of the immune spleen cells which appeared to belong to either B cells or their progeny antibody-forming cells. The differences were observed in the properties of the suppressor cells in terms of the period after the priming and the radiosensitivity; i.e., immune spleen cells taken from the mice which had been immunized with SRBC 5 days earlier were able to suppress only 19S PFC, whereas those taken from the mice which had been immunized 14 days earlier were able to suppress both the 19S and 7S PFC responses, and the former cells were susceptible to 400 R X-rays, but not the latter. These two types of suppressor cells appeared to play an important role in the regulation of the sequential change of 19S and 7S antibodies during the primary immune response

DEMONSTRATION OF VARIOUS ANTIGENS ON PARAFFIN SECTIONS OF FORMALIN-FIXED TISSUES: TRYPSIN-TREATED, IN DIRECT PEROXIDASE-LABELLED ANTIBODY TECHNIQUE

Detection of various antigens was performed on the formalin-fixed, paraffin-embedded sections by indirect peroxidase-labelled antibody technique after pretreatment with trypsin digestion. It was revealed that the optimal condition for trypsin digestion of the paraffin sections differed according to the character of antigen and type of tissue, and, under the optimal condition, this method was easily applicable to the regular paraffin sections obtained in the laboratories for routine examinations. This method was also recommended for the detection of the antigens which were usually stained even without trypsin digestion, since it could not only remove the background staining but also uncover the otherwise masked antigen

Aging of the recipients but not of the bone marrow donors enhances autoimmunity in syngeneic radiation chimeras

Young and old mice have been lethally irradiated and injected with syngeneic bone marrow cells from young or old donors to investigate whether self reactivity in old mice results from age-related damage of the radioresistant stromal cells and/or of the bone marrow hematopoietic cells. Thymus and spleen cell repopulations and mitotic responses at 3 months after irradiation are lower in old than in young recipients, suggesting age-related accumulation of stromal cell damage in the thymus as well as in other central and peripheral lymphoid tissues. The same efficiency of bone marrow cells from young and old donors to repopulate the thymus and spleen in recipients of equal age rules out the detrimental effects of aging on stem cells as well as T and B cell precursors. The serum concentration of auto-antibody and glomerular lesions at 3 and 9 months after irradiation were more pronounced in old than in young recipients and displayed no difference in recipients of equal age, regardless of the age of the bone marrow cell donors. These findings support the possibility that age-related damage of stromal cells induces disregulation of the immune system leading to autoimmune phenomena