0000000000189342
AUTHOR
Christine Claus
7-O-acetyl-GD3 in human T-lymphocytes is detected by a specific T-cell-activating monoclonal antibody.
The monoclonal antibody U5, which is a potent inducer of proliferation in human T-cells, was found to bind to an alkali-sensitive derivative of ganglioside GD3. Using immunochemical and spectroscopic methods, the structure of the U5 antigen was determined as 7-O-acetyl-GD3. The antibody U5 did not react with 9-O-acetyl-GD3 and bound severalfold more stronger to 7-O-acetyl-GD3 than to GD3. U5 is the first antibody known to detect preferentially 7-O-acetyl-GD3. Flow cytometric analysis showed that each major class of human leukocytes contained a significant fraction of cells binding the U5 antibody.
Expression of properdin in human monocytes
Properdin is the only known positive regulator of the alternative pathway of complement activation. Northern blot analysis of cell lines derived from fibroblasts, B-cells, hepatoma cells, and cells of the monocyte-macrophage lineage revealed properdin expression only in the myelomonocytic cell line HL-60, in the monoblastic cell line U-937 and in the monocytic line Mono Mac 6. Culture of Mono Mac 6 cells for 24 h with phorbol 12-myristate 13-acetate, bacterial lipopolysaccharide and the cytokines interleukin-1 beta and tumour necrosis factor-alpha enhanced mRNA abundance, with the strongest effect (tenfold) being observed with the lipopolysaccharide. In contrast, recombinant interferon-gamm…
Towards the Development of Antitumor Vaccines: A Synthetic Conjugate of a Tumor-Associated MUC1 Glycopeptide Antigen and a Tetanus Toxin Epitope.
Proliferation of cytotoxic T-cells, a prerequisite for the development of antitumor vaccines, was induced by 1, but not by its partial structures A and B. The conjugate 1 containing a tumor-associated Sialyl-TN -MUC-1 glycopeptide antigen A and a T-cell epitope B of tetanus toxin was synthesized by fragment condensation on a solid phase.
Anti-GD3 antibodies are potent activators of human gamma/delta and alpha/beta positive T cells.
The ganglioside GD3 has a variety of biological functions. These include stimulatory effects on proliferation, natural killer activity and cytokine production by freshly isolated peripheral T cells. In this study we have characterized anti-GD3 antibody (MoAb Z21) mediated effects on T cell clones. Our data indicate that alpha/beta TCR CD4+ and CD8+ as well as gamma/delta TCR positive T cells can be stimulated resulting in proliferation and cytokine production. This effect could be blocked by cyclosporin A and did not involve the LFA-3 or CD4 molecule. Apart from IFN-gamma and IL-2 production by T helper 1 and T helper 0 cells we have observed production of IL-4 and IL-10 by T helper 2 cells…
Inhibition of anti-GD3-ganglioside antibody-induced proliferation of human CD8+ T cells by CD16+ natural killer cells
The ganglioside GD3 has been described as a membrane component of human T cells which is involved in T cell growth. In the present study the activating function of GD3 for human CD4+ and CD8+ T cells was analyzed by five different monoclonal antibodies (mAb) directed against the GD3 molecule. Three mAb U5, Z21 and R24 induced strong proliferation of peripheral blood mononuclear cells and purified CD8+ and CD4+ T cells of normal donors containing less than 5% CD16+ natural killer (NK) cells. In contrast to CD4+ T cells, CD8+ T cells proliferated only weakly in the presence of 15% CD16+ NK cells. The proliferative response of purified CD4+ and CD8+ T cells (< 5% NK cells) correlated with the …
The 9-O-acetylated disialosyl carbohydrate sequence of CDw60 is a marker on activated human B lymphocytes
Gangliosides with a terminal 9-O-acetylated disialosyl group (CDw60 structures) show a restricted surface expression on human leukocytes. Hithereto, they have only been detected on subpopulations of human T lymphocytes. Using the defined CDw60 antibody UM4D4 and two new antibodies with preferential CDw60 activities, F6 and Z17, we demonstrate for the first time that CDw60 is an activation marker on human B lymphocytes. In vitro phorbol ester-stimulated human peripheral blood B lymphocytes as well as in vivo activated tonsillar B lymphocytes became CDw60 positive. CDw60 expression of these cells exceeds that of resting and activated T-lymphocytes.