A.W. Harris

Bio: A.W. Harris is an academic researcher from Salk Institute for Biological Studies. The author has contributed to research in topics: Receptor & Thymidine. The author has an hindex of 2, co-authored 2 publications receiving 584 citations.

Continuous cultures of fused cells secreting antibody of predefined specificity

Abstract: THE manufacture of predefined specific antibodies by means of permanent tissue culture cell lines is of general interest. There are at present a considerable number of permanent cultures of myeloma cells1,2 and screening procedures have been used to reveal antibody activity in some of them. This, however, is not a satisfactory source of monoclonal antibodies of predefined specificity. We describe here the derivation of a number of tissue culture cell lines which secrete anti-sheep red blood cell (SRBC) antibodies. The cell lines are made by fusion of a mouse myeloma and mouse spleen cells from an immunised donor. To understand the expression and interactions of the Ig chains from the parental lines, fusion experiments between two known mouse myeloma lines were carried out.

Derivation of specific antibody-producing tissue culture and tumor lines by cell fusion

Abstract: Cell fusion techniques have been used to produce hybrids between myeloma cells and antibody-producing cells. The hybrid lines derived are permanently adapted to grow in tissue culture and are capable of inducing antibody-producing tumors in mice. Spleens from mice immunized against sheep red blood cells (SRBC) were fused to an 8-azaguanine-resistant clone (X63-Ag8) of MOPC 21 myeloma. Over 50% of the derived hybrid lines produce and secrete immunoglobulins different from the MOPC 21 myeloma. About 10% of the hybrid lines exhibit anti-SRBC activity. The high proportion of antibody-producing hybrids suggests that the fusion involves a restricted fraction of the spleen cell population, probably cells committed to antibody production. In order to avoid the presence of the MOPC 21 heavy chain in the specific hybrids, another myeloma cell line (NSI/1-Ag4-1) has been used. This is a nonsecreting variant of the MOPC 21 myeloma which does not express heavy chains. Three anti-SRBC (probably of the mu, gamma2b and gamma1 classes, respectively) and two anti-2,4,6-trinitrophenyl (of the mu class) antibody-producing hybrids have been repeatedly cloned. By random selection and by selection of specific clones according to their lytic activity (clone plaque selection), a number of different lines have been constructed. Such lines express different combinations of the four possible chains of each hybrid line: the myeloma gamma and K chains and the specific antibody heavy and light chains. In three cases (Sp1, Sp2 and Sp7) it is shown that only the specific H and L combination has activity and that the myeloma chains are unable to substitute for them. In most cases lines have been derived which no longer express the MOPC 21 chains but only the specific antibody chains.

Corticosteroids and lymphoid cells.

Abstract: GLUCOCORTICOSTEROID hormones of the adrenal cortex have striking pharmacologic effects on lymphoid tissues and cells. These effects form part of the basis for the widespread use of these hormones in the treatment of a variety of diseases involving immunologic, inflammatory or neoplastic processes. The subject is large and has been reviewed in the past,1 2 3 4 5 6 7 but many questions remain to be answered. The purpose of this article is to take a new look at the subject, concentrating on three aspects. The first is species differences in susceptibility to corticosteroids. (Although these differences have been noted before, they are often overlooked; they . . .

Fusion between immunoglobulin-secreting and nonsecreting myeloma cell lines.

Abstract: The defects in two nonsecreting variant clones of the mouse plasmacytoma MOPC 21 (P3) were studied by tissue culture methods. The variants (NSI and NSIII) do not synthesize detectable heavy chains. NSI synthesizes, but does not secrete, light chains and NSIII does not synthesize light chain. A screening procedure was used allowing the detection of revertant cells secreting immunoglobulin. The method is based on a hemolytic plaque assay using anti-immunoglobulin-coated red cells. No revertants were detected among 2 x 10(7) cells. Both variant lines were fused to another myeloma line (PI) which secretes a complete immunoglobulin and excess light chains. Analysis of the products by isoelectric focusing showed that in the hybrids there was no reactivation of synthesis of the nonexpressed chains. The defects leading to loss of synthesis cannot therefore be complemented in the hybrid lines. The secretion of light chain in NSI, on the other hand, could be complemented in the hybrid but the light chain was only secreted as part of a new immunoglobulin hybrid molecule.