Hu Ly-M3--a human leukocyte antigen.

A monoclonal antibody, 5-4.8, was produced against human peripheral blood lymphocytes and it appears to be leukocyte-specific in that it reacts with a common determinant (called Hu Ly-m3) present on the peripheral blood T, B and null lymphocytes of 40 individuals. The antibody also reacts with thymocytes, spleen cells, and bone marrow cells (30%) and weakly with granulocytes and platelets--but not with heart, liver, or kidney.

Localization of human colorectal tumor xenografts in the nude mouse with the use of radiolabeled monoclonal antibody.

For the evaluation of the clinical usefulness of monoclonal antibodies as diagnostic or therapeutic reagents, tumor localization must be clearly demonstrated in an experimental model. In this report, nude mice carrying two human tumor xenografts--a colon carcinoma (Colo 205) and a melanoma (Colo 239)--were given ip injections of radiolabeled monoclonal antibodies. Monoclonal antibody 250-30.

A monoclonal anti-pan-T-cell antibody. In vitro and in vivo studies.

A murine monoclonal antihuman T cell antibody is described that is pan-T in that it reacts with all T cells, including those from thymus, but not with B cells or other cells, except for a small subpopulation of null cells. Biochemical analysis demonstrated that the antigen detected is a glycoprotein, Mr 50,000 daltons, in which sialic acid, alpha-fucose and alpha-mannose are the important terminal or subterminal carbohydrates. Further analysis indicated that the antigen is the E-rosette-forming-cell (ERFC) receptor or a closely associated structure.

Detection of glycoprotein IIb and IIIa by monoclonal antibodies.

Murine monoclonal antibodies were produced against human platelet membranes and screened on platelets by a 125I protein A radioimmunoassay. Several clones produced platelet specific antibodies as they showed no reaction with peripheral blood lymphocytes, neutrophils, bone marrow (excluding megkaryocytes) or several cell lines. Two antibodies (designated anti-HuPl-m1a and anti-HuPl-m1b) were of particular interest in that although platelet specific they were non-reactive with platelets from a thrombasthenic patient.

Description of a new Qa antigenic specificity, "Qa-m9," whose expression is under complex genetic control.

The "Qa-m9" specificity has been defined by a monoclonal antibody, and evidence for three-gene control of its expression has been demonstrated. The Qa allocation was made on the basis of H-2 linkage (H-2 congenic strains, Rl lines), differential reaction with B6.K1 and B6.

Description of a mouse monoclonal anti-HLA-B27 antibody HLA-ABC-m3.

The production and characterization of a new anti-HLA-B27 monoclonal antibody HLA-ABC-m3 is described. This cytotoxic IgG2a antibody binds protein A and is able to precipitate cell surface molecules of 43,000 and 12,000 daltons corresponding to the HLA heavy chain and beta 2-microglobulin. Population testing revealed that the HLA-ABC-m3 antibody reacted with the peripheral blood lymphocytes of 47/47 individuals conventionally typed as HLA-B27+ and with 5/105 HLA-B27- individuals.

A function for human T200 in natural killer cytolysis.

The ability of an antihuman T200 monoclonal antibody, F2.5, to specifically inhibit in vitro human natural killer cell-mediated lysis of K562 target cells is demonstrated. No inhibition by the F2.

Differential expression of Qa-m2 alloantigen on murine hemopoietic progenitor cells. Selective enrichment for megakaryocyte progenitors.

The selective expression of Qa-m2 antigen on murine megakaryocyte colony-forming cells (MEG-CFC) has been demonstrated. A monoclonal antibody defining the Qa-m2 alloantigen has been shown to inhibit, in the presence of complement, in vitro formation by murine bone marrow cells of megakaryocyte colonies, but not granulocyte-macrophage, erythroid or eosinophil colonies. Inhibition of megakaryocyte colony formation was shown, by mixing and other experiments, to be due to C-mediated lysis of MEG-CFC rather than lysis of accessory cells.

Human 'Ia' antigen populations defined by monoclonal antibodies.

The relationships between the antigens recognized by four monoclonal anti-human 'Ia'-like antibodies were investigated using sequential immunoprecipitation and capping techniques. Two of the antibodies were 'monomorphic' and have previously been shown to recognize epitopes in which carbohydrate residues are involved, whereas the two 'polymorphic' antibodies recognized protein-defined epitopes--one of these epitopes being present on MB+DR- molecules. In the absence of an indisputable anti-DR monoclonal antibody, it was not possible to conclusively verify which 'Ia'-encoded antigens were detected by the anti-'Ia'-like monoclonal antibodies.

Macrophage procoagulant activity as a measure of cell-mediated immunity in the mouse.

Thioglycollate-induced peritoneal exudate cells (TG-PEC) developed increased procoagulant activity after incubation with lymphokine and lipopolysaccharide (LPS). Dilutions of up to 1/1000 for insoluble Con A and 1/200 for periodate-induced lymphokine supernatants were active in enhancing macrophage procoagulant activity (MPCA), which was detected after a 2-hr incubation period and steadily increased over 20 hr. MPCA could also be induced by antigen; peritoneal cells from sensitized B6AF1 mice with strong footpad reactions to ovalbumin (OVA) responded to as little as 0.

Monoclonal antibodies to human colon and colorectal carcinoma.

A series of monoclonal antibodies was produced by immunizing mice with fresh carcinoma of the colon and with the cell line HT-29. These antibodies could be classified into 3 different groups: (a) those which were HT-29 specific and reacted with no other cell line or fresh colon carcinoma samples; (b) antibodies which reacted with HT-29 and were also reactive with a number of other in vitro cell lines; and (c) antibodies which appeared to be specific for carcinoma of the colon cell lines in that they reacted selectively with colon carcinoma cell lines and not with carcinoma lines derived from other tissues. It was clearly shown by immunoperoxidase staining of both normal and neoplastic cells of the gastrointestinal mucosa, from stomach to colon, that these antibodies were not tumour-specific.

Hu Ly-m5: a unique antigen physically associated with HLA molecules.

A new human cell surface antigen (Hu Ly-m5) detected by a murine monoclonal antibody (E4.3) is described. The tissue distribution of the Hu Ly-m5 antigen is similar to the HLA antigens (with which it was initially confused) but it is not present on all bone marrow cells nor the U266 myeloma, and is expressed on the HLA-negative K562 cell line.

Restriction in adoptive transfer of resistance to Listeria monocytogenes. I. Influence of non-H-2 loci.

In vivo adoptive transfer of T-cell-mediated immunity to the facultative intracellular bacterium Listeria monocytogenes is restricted, not only by the H-2 haplotype of the mice, but also by incompatibilities at non-H-2 loci. Thus, transfer between H-2 identical strains of mice with different background genes was reproducibly and significantly less efficient than transfer between completely syngeneic mice, although the restriction was less marked than that across the H-2 barrier. Restriction also occurred when parental cells were injected into semisyngeneic F1 hybrids and when cells from F1 hybrids were injected into parental strains.

The definition of an MB related specificity by a monoclonal antibody.

A number of monoclonal antibodies have been described that react with monomorphic and polymorphic Ia-like specificities on human B cells, but it is not clear whether these react with HLA-DR encoded molecules or with the products of other closely linked genes within the MHC, such as MB, MT, or DC 1 antigens. A monoclonal antibody is described herein (MC-26.1) which detects a new Ia-like specificity as shown by B-cell reactivity, chemistry, family studies, including recombinant family and coprecipitation studies.

A human breast tissue-associated antigen detected by a monoclonal antibody.

Two monoclonal antibodies were produced in mice immunized with the human breast carcinoma cell line MCF-7. One antibody (24-17.1) reacted with MCF-7 and other breast tumor cell lines and detected an antigen of Mr 95,000.

Monoclonal antibodies in clinical medicine--a review.

Monoclonal antibodies are produced by the cell fusion method, whereby immune murine spleen cells are fused with a murine myeloma to produce large quantities of specific homogeneous antibodies. These have obvious advantages over conventional antisera particularly for in vitro diagnostic procedures. The use of monoclonal antibodies to human T cells, leukaemias and solid tumours are reviewed.

Differentiation markers and accessory function of murine macrophages derived from cultured bone-marrow stem cells.

Murine bone-marrow cells cultured in the presence of colony-stimulating factor from mouse-lung-conditioned medium give rise to macrophages which function as accessory cells in antigen-specific T helper cell induction. Virtually all Ia+ bone-marrow stem cell-derived macrophages express determinants encoded in the I-A subregion. A second set of macrophages bears I-A as well as I-E/C-endoced determinants.

Monoclonal antibodies to B cells.

Monoclonal antibodies (Mab) have defined functional T lymphocyte subsets in mouse and man: Ly-1/OKT4 positive helper T cells, Ly-123/OKT8 positive killer T cells and Ly-23/OKT8 positive suppressor T cells. An equivalent array of useful reagents for B-cell subsets is not yet available-although many laboratories are trying to produce them. In this review Ian Mckenzie and Heddy Zola summarize the Mob which are available and which detect polymorphic or monomorphic determinants on the B-cell surface in both man and mouse.

Monoclonal antibodies to drugs--digoxin.

A number of monoclonal antibodies to digoxin, two of which have been further characterized, were produced by somatic cell fusion. No cross reactivity with chemically related drugs was detected. Preliminary in vivo studies showed altered digoxin pharmacokinetics in antibody treated mice.

The H-2dm1 mutation and Qa antigens.

The effect of the H-2dm1 mutation on Qa-m2 expression was examined. The mutant strain B10.D2-H-2dm1 showed a fourfold increase in Qa-m2 expression when compared with the parental strain B10.

An analysis of T lymphocyte subsets in tumour-transplanted mice on the basis of Lyt antigenic markers and functions.

Small lymphocyte subsets were characterized radioautographically on the basis of several surface markers, . surface Ig (S-Ig), Thy-1 and Lyt (Ly-1, Ly-2 and 3) antigens in host lymphoid organs (thymus, spleen and blood) as well as at the tumour site at various stages of subcutaneous growth of two different syngeneic tumours—MPC-11 plasmacytoma and WEHI-164 fibrosarcoma in BALB/c mice. In both tumour-host combinations there was a rise in the levels of null (S-Ig, Thy-1) small lymphocytes as well as the Ly-23 subset of T small lymphocytes at all the sites examined.