Morris K. Barrett

A STRAIN-SPECIFIC INFLUENCE OF PARITY ON RESISTANCE TO HOMOGRAFTS *

The homograft problem is often looked upon from a theoretical standpoint as somewhat of an artifact or laboratory curiosity, although its practical aspects are forced upon the attention of clinicians. The question may be asked, “What purpose is served by transplantation antigens and antibodies in nature?” In our speculations we have adopted the viewpoint that what we call antigens, antibodies, and immunity in this special context are probably elements of a biological information system of broad application and that they might carry other names had we the knowledge to assign them. Gestation in mammals is one naturally occurring phenomenon that 5eems related to the subject. In randomly bred populations the fetus and mother have genetic relationships similar to those between F1 hybrids and parental strains, if differences between homozygous and heterozygous populations are temporarily disregarded. A hybrid graft is not expected to grow in the maternal strain but, apparently, the mammalian fetus is an exception. Probably many factors are operative, but we wondered if some other evidence of “tolerance” in the mother could be 0bserved.t One of the first questions was, “Does the mother acquire some sort of tolerance demonstrable by current techniques?” We have found that she does in that, after females of one inbred strain were mated to males of their own strain or of a second strain, the post-partum females of the latter class exhibited tolerance toward a homologous graft isologous with the second strain. This was seen only in those females previously mated to males genetically related to the graft and not in those mated to males of their own strain or of a third strain unrelated to the graft.

An apparent specificity in digestion of living gastric mucosa in rats.

Summary Inbred rats were used in experiments designed to discover if some sort ofspecificity was involved in the usual failure of the stomach to digest itself. It was found that, under the conditions imposed, normal glandular mucosa in each strain is resistant to its own secretion but each is vulnerable to the secretion of a different rat. The results suggest that among the interrelation-ships of the mucosa, the enzymes, and some third element, possibly in the mucus, there is a relationship (s) involving a relative specificity.

Degenerative Changes in the Mucosa of Artificial Gastric Polyps in Dogs

Summary Polypoid redundancy of the gastric mucosa was produced in dogs by a plastic surgical procedure. At the beginning the mucosa was apparently normal and no other treatment was given. After prolonged periods of observation, atrophic gastritis was found on the polyps but not elsewhere in the stomach. Implications of this are discussed.

Some observations on the lack of mutual effects between the stomach and a jejunal graft implanted therein.

Summary During the course of experiments performed for other purposes on dogs opportunities have occurred to make numerous incidental observations which support the opinion that, within the limitations of present conditions and methods, the mucosa of a jejunal pedicle graft can withstand active peptic digestion for very long periods of time and, conversely, the secretion of acid by the stomach is not changed by the presence of jejunal mucosa or its secretions.