A partially histocompatible family of Xenopus borealis.

Reciprocal skin allografts were made between siblings of three successive generations in a family of Xenopus borealis and mutually tolerant animals were mated. In the F3 generation of one subfamily, 92% of the siblings were histocompatible.

The primary structure of a rat kappa Bence Jones protein: phylogenetic relationships of V- and C-region genes.

The complete amino acid sequence of a LOU rat k Bence Jones protein, S211, is presented. The availability of such a sequence makes it possible to re-evaluate the phylogenetic relationships of V- and C-region genes. The data suggest that V- and C-genes, and also V-genes between themselves have evolved at different rates.

Transplantable immunoglobulin-secreting tumors in rats. VI. N-terminal sequence variability in LOU/C/Wsl rat monoclonal heavy chains.

Most of the spontaneous ileocecal immunocytomas of LOU/C/Wsl strain rats secrete large amounts of monoclonal immunoglobulins. Amino acid sequence studies were undertaken on the heavy chains of 13 of these proteins and on pooled heavy chains from LOU rats to define the structural variability in the amino terminal region of the rat heavy chain. Characteristic VHIII sequences were found in both the myeloma proteins and the heavy chains from the pool.

Transplantable immunoglobulin-secreting tumours in rats. IV. Sixty-three IgE-secreting immunocytoma tumours.

The inbred LOU/Wsl rat strain presents a high incidence of spontaneous ileocoecal immunocytoma which secrete monoclonal immunoglobulins. These tumours are transplantable in histocompatible animals and their secreting properties are maintained over many passages. A screening of monoclonal immunoglobulins secreted by 250 such tumours revealed sixty-three proteins which shared class-specific determinants, physicochemical features and biological properties different from those of rat IgM, IgA, IgG1, IgG2a, IgG2b and IgG2c classes, and characteristic of proteins of the IgE class.

Studies on the IgA system of the horse.

Equine serum and secretions were found to contain a protein which cross-reacted with an antiserum against human IgA, but not with antisera against any other human immunoglobulin. The physicochemical properties of equine IgA resembled those of human IgA. IgA was found to be the immunoglobulin having the highest secretion serum concentration ratio in equine lacteal and salivary secretions, and to be the protein produced by the majority of immunoglobulin-containing cells in the of the equine intestine.