Abrogation by subsequent feeding of antibody response including IgE, in parenterally immunized mice

We have investigated the possibility of oral administration of ovalbumin (OVA) to prevent a secondary antibody response and interrupt reaginic antibody production. Repeated feeding seems necessary for both. Quality of results was dependent on the number of ingestions. Differences in abrogation of antibody response between mice strains were observed. Best results were obtained with AKR mice, good suppression was seen in C3H strain, and inconsistent results were obtained with DBA/2. 10 OVA oral doses were necessary to prevent a secondary antibody response in parenterally immunized mice, but 4 doses interrupted reaginic production in sensitized AKR mice. These results demonstrate that antigen feeding can prevent a secondary antibody response and interrupt reaginic antibody production.

Gastric ulcer disease: gastric ulcer induced by mucosal anaphylaxis in ovalbumin-sensitized Praomys (Mastomys) natalensis

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Protective immunity and the cell-mediated immune response in mice following oral administration of an avirulent strain of Salmonella typhimurium

Oral vaccination with Salmonella typhi-murium M 206 has been shown to confer highly significant protection on BALB/c and low-responder (LR) Biozzi mice a 30 days, but no protection was observed in high-responder (HR) Biozzi mice. None of the three strains showed any evidence of significant protection 10 days after primary vaccination. A correlation was noted between the degree of protection and the results of tests measuring cell-mediated immunity, both in vitro (MIF test), and in vivo (colloidal carbon clearance). Phagocytosis was significantly more active in vaccinated mice, both at days 10 and 30, except in HR mice. MIF production was only found at day 10 in HR mice, and was present at day 30 in both HR and LR mice. Our results emphasize the importance of the role of macrophage phagocytosis in the protection of mice against Salmonella infections.

Role of homocytotropic antibodies in pathogenesis of gastric ulcer

Praomys (Mastomys) natalensis were sensitised by peritoneal injection of ovalbumin mixed with aluminium hydroxide. The animals developed homocytotoropic IgE and IgG 1 antibodies. When presensitised animals were challenged with ovalbumin in the gastric wall, a gastric ulcer appeared. This ulceration, induced by an immunological release of histamine, could be inhibited by the administration of disodium cromoglycate. The present model is useful for producing a gastric ulcer in a determined site. It supports the theory of a possible allergic component in the pathogenesis of the human disease.

Distribution of IgA 1 and IgA 2 plasma cells in various normal human tissues and in the jejunum of plasma IgA-deficient patients

The distribution of IgA 1 and IgA 2 plasma cells was studied in normal human tissues. IgA 2 is a minor constituent in peripheral lymph nodes as well as in serum and in bone marrow plasma cells. An increased proportion of IgA 2 plasma cells was observed in gastric and intestinal mucosa, as well as in bronchial mucosa and salivary and mammary glands. Tonsils and mesenteric lymph nodes exhibit values intermediate between those of central and peripheral lymphoid systems. In patients with plasma IgA-deficiency, IgA 2 is the predominant intestinal IgA plasma cells. This may explain the frequent association of an asymptomatic condition and plasma IgA deficiency.

Response of anamnestic IgA-producing cells in the mouse gut after repeated intragastric immunization

1) Repeated intragastric immunization after a 90-day interval results in a local immunologic memory. 2) Repeated intragastric immunization does not induce the same circulation of gut lymphocytes as does the initial oral immunization. 3) Measurement of circulating antibodies is a poor criterion for gauging the local immune status. 4) A gastric intubation dose of 4 X 10(9) SRBC given daily for 4 days appears to be suboptimal for the induction of a local immune response.

Effect of cimetidine on tritiated thymidine incorporation by the stomach, jejunum, colon, liver and spleen of mice

The administration of cimetidine to mice at a dose of 200 mg/kg and per 24 h inhibits the tritiated thymidine incorporation by the stomach, jejunum, colon and liver and stimulates incorporation by the spleen. These results may furnish an explanation for the rare secondary effects observed in humans. It is also proposed that endogenous histamine may play a role of cytohormone, regulating tissue trophicity.

Effect of food intake on circulating antigen-antibody complexes in patients with alcoholic liver cirrhosis

Serum antibodies directed against 5 alimentary antigens and antigen-antibody complexes were determined in 15 control subjects and in 15 patients with alcoholic liver cirrhosis. Cirrhotic patients presented an increased immune response against these antigens. Antigen-antibody complexes were detected in the fasting plasma of 7 cirrhotic patients. The level of immune complexes increased in 6 out of these 7 patients 1 h after lunch.

[Regeneration of the reproductive system and differentiation of extra-gonadic germ cells inEisenia foetida Sav.]

The regeneration of the reproductive system from the body wall reduced to its parietal mesoderm covered with epidermis has been studied in adult worms. It has enabled us to show that each reproductive organ can normally become differentiated independently of the others, from determined territories in the older parietal mesoderm.An extra-gonadic germ line is liable to be formed in the coelomic layers, particularly in the ventral region of the genital segments. This line may become differentiated as male but not as female.The extra-gonadic germ elements appearing in the female territory are incapable of complete self-differentiation.

[Consequences of experimental triploidy on the fertility and sexual differentiation of a normally amphigonic and diploid lombrician, Eisenia foetida Sav]

The fertility of experimental triploid worms has been studied in Eisenia foetida Sav. This study has led us to the conclusion that the female germ line is abortive while the male germ line may as an exception take part in fertilization. Histological controls have confirmed the differentiating ability of the male line and the break in the development of the female line.

[Delayed-type hypersensitivity induced by digestive immunization and suppression of this induction by antigen-antibody complexes (author's transl)]

BALB/c mice were immunized by intragastric administration of sheep red blood cells or horse red blood cells repeated daily for 4 days. The immunized animals when skin tested with an urea extract of the corresponding antigen showed a delayed-type hypersensitivity reaction. This reaction was observed for 4 weeks after the immunization. This result demonstrates that digestive immunization may induce cellular immunity. When serum from intragastrically immunised mice containing antigen-antibody complexes was administered intraperitoneally 8 hours before the onset of digestive immunization, the subsequent delayed-type hypersensitivity reaction was suppressed or considerably depressed.