Comparison of binding specificity and the function of two human IgM anti-lipid A monoclonal antibodies.

The interactions of two anti-lipid A monoclonal antibodies (mAb)--HA-1A and SdJ5-1.17.15--with their antigenic sites on lipid A, were compared using a dot-blot assay and lipid A structural analogues, as well as lipid A-high-density lipoprotein (HDL) complexes.

Inhibition of lipopolysaccharide-associated endotoxin activities in vitro and in vivo by the human anti-lipid A monoclonal antibody SdJ5-1.17.15.

The present study evaluated the effect of a novel anti-lipid A monoclonal antibody, termed SdJ5, on the in vitro production of tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta by endotoxin- or lipopolysaccharide (LPS)-challenged human peripheral blood mononuclear cells (hPBMC). In addition, the present study determined whether SdJ5 could neutralize the in vivo toxicity of LPS. SdJ5, at a concentration equal to or greater than 3 micrograms/ml, specifically inhibited TNF-alpha and interleukin-1 beta production by hPBMC stimulated with every type of LPS and lipid A assessed.

Lipopolysaccharide epitope specificity and binding cross reactivity of the human IgM anti-lipid A monoclonal antibody SdJ5-1.17.15.

The binding properties and specificity of the SdJ5-1.17.15 (SdJ5) human IgM monoclonal antibody (mAb), prepared against S.

Cloning and reexpression of a functional human IgM anti-lipid A antibody.

The human hybridoma cell line HR78 secretes a human antibody of the IgM isotype directed against bacterial endotoxin. The cell line produces low levels of antibody and, more importantly, the antibody product is likely to be impure since two and perhaps more species of heavy chain are being synthesized as judged by cloning and expression studies. To address these issues, the cell line was used as a source of mRNA for the construction of cDNA libraries and the subsequent isolation of the sequences encoding heavy and light chains.

Growth stimulating activity produced by human bladder cancer cells.

Growth promoting properties have been identified in the conditioned serum-free medium from cultures of the human transitional cell carcinoma cell line 647V. This activity appears to reside in a molecule of more than 5000 MW. The factor responsible for 647V growth is distinguished from epidermal growth factor, since it fails to inhibit the specific binding of epidermal growth factor by 647V cells, and 647V cells are not stimulated to grow by epidermal growth factor.

Murine hybridoma antibodies against human transitional carcinoma-associated antigens.

Spleen cells from mice immunized with the human urinary bladder transitional cell carcinoma cell line 647V have been fused with a syngeneic myeloma cell line to produce hybridomas. Screening of supernatants from 40 hybridomas which reacted with the immunizing cell line identified antibodies recognizing a variety of common, shared and tumor-associated antigens as well as newborn calf serum dependent antigens. Three hybridoma antibodies, 9A7 , 2E1 and 2A6 , recognize antigens found on all the human transitional cell carcinoma cell lines and tissue preparations tested, but the antigens were not found on normal human tissue (including urothelium), thus demonstrating the capability of the antibodies to distinguish normal from malignant bladder transitional epithelium.

Identification and linkage analyses of a gene, Rcs-1, suppressing spontaneous SJL/J lymphoma expression.

Populations of SJL/J (SJL), A.SW/SnJ (A.SW), F1, and backcross mice were followed over 2 years for the spontaneous development of reticulum cell sarcoma (RCS).

Single-gene abrogation of spontaneous pleomorphic SJL/J mouse reticulum cell sarcoma expression.

Inbred SJL/J and A.SW/SnJ mice have been bred to produce (SJL female X A.SW male)F1 and A.

Thermo-magnetic surgery for experimental renal cancer.

Thermo-magnetic surgery is an innovative modality in the treatment of malignancies. This unique combination can produce selectively controlled destruction of deep tumors. Heating of the magnetic metallic compounds of ferrosilicone by hysteresis produces temperatures which are incompatible with cancer cell survival.

Serum-free medium for the in vitro growth of normal and malignant urinary bladder epithelial cells.

A serum-free medium, DH-S1, is described which is valuable for the establishment of primary cultures of normal and malignant transitional epithelium (transitional cell carcinoma of the bladder). Growth of epithelial cells in DH-S1 is facilitated but that of fibroblasts is suppressed. Another established human transitional cell carcinoma cell line, 647V, has grown continually in DH-S1 for over 36 passages.

Induction of canine in vitro reactivity to alloantigen following intralymphatic immunization.

An experimental model has been developed using the dog to study the induction of systemic cell-mediated immunity following intralymphatic immunization (ILI) with allogenic cells. As detected in one-way mixed lymphocyte cultures, blastogenically-reactive immune peripheral blood lymphocytes were observed after the third ILI with 10(7) cells. The in vitro reactivity was augmented by a fourth ILI to a node not previously injected indicating that a response in one node was followed by the trafficing of memory cells to other nodes.

Stimulation of murine lymphocytes by Rauscher leukemia virus in vitro.

Murine lymphocytes cultured with frozen and thawed Rauscher murine leukemia virus 100,000 x G supernatants demonstrated increased 3H-thymidine uptake. The stimulatory capacity co-purified with the major envelope glycoprotein, gp70, and can be specifically removed from viral supernatants by absorption with anti-gp70 antibody-linked Sepharose. Cells from all strains tested, including strains prone to autoimmune disease (MRL/1, (NZB X W)F1, NZB, and BXSB), immunologically normal strains (DBA/2, C57B1/6, BALB/c, C3H and 129/J), genetic low responders to LPS (C3H/HeJ), and mice congenitally T cell deficient (BALB/Wehi nu/nu) were equivalently responsive to viral protein stimulation.

Nonrandom inclusion of H-2K and H-2D antigens in Friend virus particles from mice of various strains.

Friend murine leukemia virus (FV), isolated from infectious serum of several mouse strains, has been examined for the presence of H-2 antigens. Following banding of the virus on a discontinuous sucrose gradient, pelleting, and disruption with Nonidet P-40 detergent, virus preparations were tested for their capacity to inhibit the lysis of target cells mediated by various anti-H-2K or anti-H-2D antisera. Virus from mice homozygous for the H-2b, H-2d, H-2g H-2k, and H-2ol haplotypes or heterozygous for the H-2g/H-2k, H-2b/H-2d, and H-2b/H-2k haplotypes was used.

Mechanisms of the H-2 effect on viral leukemogenesis.

Evidence has been gathered which supports the notion that two distinct but interacting mechanisms, controlled by loci mapping within the H-2 complex, influence Friend murine leukemia virus (FV) disease. One mechanism, controlled by a gene mapping in or close to H-2D, influences the capacity of the H-2D gene product to form molecular complexes with FV molecules in the plasma membrane of infected cells. Formation of a complex appears to provide a target antigen for syngeneic cytotoxic T-lymphocytes, to cause co-capping of FV and H-2D antigens, to permit the selective inclusion of H-2Db molecules into progeny Friend virions, to influence the long-term maintenance of virus production in vitro and, in conjunction with the second mechanism, to stimulate the generation of cytotoxic T-lymphocytes.

Studies of the mechanism of lymphocyte-mediated cytolysis. VII. Two stages in the T cell-mediated lytic cycle with distinct cation requirements.

The lysis of allogeneic cells by cytolytically active T lymphocytes has been shown to involve two stages, Each with distinct cation requirements. Cytolysis required the presence of Ca++ ions, but addition of Mg++ to Ca++ containing medium synergistically enhanced target cell destruction. This synergistic effect resulted form kinetically separable events mediated by these cations.

Studies on the mechanism of lymphocyte-mediated cytolysis. V. The use of cytochalasins A and B to dissociate glucose transport from the lytic event.

The lysis of DBA/2 mastocytoma cells (P815) by alloimmune C57BL/6 thymus-derived lymphocytes was inhibited by cytochalasin A (CA) and cytochalasin B (CB). Although CB prevented incorporation of glucose into lymphocytes, the effector cell susceptibility to the drug was independent of the hexose content of the culture medium. Indeed, cytolysis occurred in the absence of exogenous hexose.

Studies on the synthetic capacity and antigenic expression of glutaraldehyde-fixed target cells.

Mastocytoma cells (P815 of the DBA/2 strain) treated with increasing concentrations of glutaraldehyde were concurrently evaluated for their ability to incorporate exogeneous uridine, thymidine, and amino acids. The antigenic expression and membrane integrity of these treated cells were assayed by measuring their susceptibility to lysis by antibody and complement and by T-effector cells. The concentrations of glutarladehyde required to effect target cell antigen display were greater than those required to inhibit totally the cell's protein and nucleic acid synthetic processes.