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J F Bach

Publications and source records attributed to J F Bach.

At least 595 records · Page 33Linked to original sources
PubMed1980

Specific receptors for the serum thymic factor (FTS) in lymphoblastoid cultured cell lines.

The interaction of the synthetic serum thymic factor (FTS, "facteur thymique sérique") with human T lymphocytes from two established T cell lines (1301 and HSB2) was studied by using [3H]FTS. At 30 degrees C, in the presence of 10 nM labeled FTS, a steady state was observed within 120 min. Bound labeled FTS was dissociated by simultaneous addition of an excess of unlabeled FTS (dissociation constant Kd = 3 nM). The binding of [3H]FTS was reduced to 10-20% when unlabeled FTS was added at 20 microgram/ml (20 micro M), but not when unrelated peptides or FTS analogues differing from FTS by only one amino acid residue were added. No FTS binding was detectable on B and null cell lines or on two T cell lines other than 1301 and HSB2. These data indicate that only certain T cell subsets possess receptors with high affinity and specificity for FTS.

Cell Line↗
PubMed1980

Cytoplasmic localization of FTS (facteur thymique sérique) in thymic epithelial cells. An immunoelectronmicroscopical study.

This study was concerned with the localization of the facteur thymique sérique (FTS) by immunoelectronmicroscopy in cultured thymic epithelial cells. The FTS antibodies labelled differently sized cytoplasmic vacuoles containing a substance of variable density. This substance occurs occasionally in crystalline structures which reacted strongly with purified FTS antibodies. On the ultrastructural level the FTS-positive cells were demonstrated to fix specifically keratin antibodies and to contain tonofilaments. Some of these cells originated from the thymic medulla proved by the presence of microvilli-forming cytoplasmic vacuoles. The existence of FTS-positive crystalline inclusions confirmed the hypothesis of a storage process in the cytoplasm of thymic epithelial cells in vitro or in pathological conditions.

Animals↗
PubMed1980

In vitro characteristics on human lymphocyte functions of a new immunomodulatory agent, a cyclic peptide, cyclomunine.

Cyclomunine, a cyclic peptide extracted from Fusarium equisiti, inhibits responses of human lymphocytes to mitogens, soluble antigens and allogeneic cells and the proliferation of lymphoblastoid cell lines. Cyclomunine has little effect on small lymphocytes but acts rather on lymphoblasts. It has no effect on fibroblasts and myeloid cells. Cyclomunine partially inhibits the generation of suppressor cells induced by Con A and the generation of cytotoxic T cells in a mixed lymphocyte culture and totally inhibits the in vitro synthesis of Ig by PBL. Cyclomunine merits consideration as a new in vitro anti-lymphoblastic agent.

Cell Membrane↗
PubMed1980

Induction of differentiation in human marrow T cell precursors by the synthetic serum thymic factor, FTS.

The serum thymic factor, 'facteur thymique serique' (FTS), was analysed in vitro for its ability to induce differentiation of normal human marrow T cell precursors into cells with T lymphocyte characteristics. FTS has been isolated, characterized, sequenced and synthesized. In the mouse, natural and synthetic FTS have similar activities in vitro in the rosette inhibition assay. Both substances influence a variety of T cell differentiation markers and functions in vivo. In this study, we found that synthetic FTS induced appearance of two T cell surface markers, HTLA phenotypes and the ability to form E rosettes, on a selective population of normal human marrow cells sedimenting in layers II or III of a Ficoll discontinuous density gradient. In addition, a population of lymphoid cells also found in layer III, which bears receptors for peanut agglutinin (PNA), was decreased in number following exposure to FTS. In the same gradient layer, cells which expressed terminal deoxyribonucleotidyl transferase (TdT) activity showed decreased activity after treatment with FTS. Functional activities characteristic of T lymphocytes were also enhanced in marrow cells of gradient layer III after preincubation with FTS. These T cell functions were demonstrated in marrow cells by their ability to respond and to stimulate allogeneic peripheral blood lymphocytes (PBL) in mixed lymphocyte reactions and by responses to phytomitogens, PHA, Con A and pokeweed. These changes were not observed in marrow cells of gradient layers I, IV and V or after incubation with an FTS analogue that lacked biological and antigenic activity in the mouse system.

Antigens, Surface↗
PubMed1980

Direct evaluation of class-specific anti-DNA antibodies by an immunoenzymatic technique.

Antibodies against native DNA have been evaluated by an immuno-enzymo assay (ELISA) using glucose oxidase labelled Ig class-specific antibodies. Results of the ELISA test were significantly correlated with those of the Farr test performed with native DNA as well as with the degree of clinical activity. ELISA is proposed as a simple method for the direct evaluation of class-specific anti-native DNA antibodies in systemic lupus and related diseases.

Antibodies, Antinuclear↗
PubMed1980

Characterization of facteur thymique sérique (FTS) in the thymus. I. Fixation of anti-FTS antibodies on thymic reticulo-epithelial cells.

Facteur thymique sérique (FTS) is a circulating nonapeptide inducing T cell differentiation. Its strict thymus dependency, already shown by its disappearance after thymectomy and its presence in thymus extracts, was confirmed using indirect immunofluorescence or immunoperoxidase by the binding to reticulo-epithelial cells of an antibody produced against synthetic FTS. The specificity of the reaction was demonstrated by the inhibition of binding observed after preincubating the anti-FTS antibody with synthetic FTS.

Animals↗
PubMed1980

Characterization of facteur thymique sérique (FTS) in the thymus. II. Direct demonstration of the presence of FTS in thymosin fraction V.

Thymosin fraction V was submitted to the same purification procedure as used for the isolation of the circulating thymic factor (FTS) from pig serum: an FTS-like material was isolated from this fraction and shown to have similar activity, molecular weight, charge and amino acid composition as FTS. These data, together with previous experiments showing the binding of anti-FTS antibodies to reticulo-epithelial cells, provide a direct argument in favour of the presence of FTS in the thymus.

Amino Acids↗
PubMed1980

[Immunopathology of arterial diseases (author's transl)].

The clinical manifestations of necrotizing angeiitis are of many types (periarteritis nodosa, Wegener's granulomatosis, hypersensitivity, vasculitis...). Their immunological origin is strongly suggested by their analogy with the experimental models of immune complex diseases, and the presence of many immunological anomalies indicating the presence and intervention of these complexes. Several arguments strongly suggest that immunological factors may be also implicated in the pathogenesis of arterial hypertension and arteriosclerosis.

Antigen-Antibody Complex↗
PubMed1980

[Thromboembolic manifestations in systemic lupus erythematosus (author's transl)].

Among 60 patients (56 females, 4 males) with severe forms of SLE, 13 developed thromboembolic arterial and/or venous manifestations, an overall incidence of 21.6 percent. Thrombophlebitis episodes, mainly affecting lower limbs, occurred in 8 patients, usually an initial or early manifestation of active lupus disease; thrombophlebitis was recurrent in two, and pulmonary embolism was proved in two patients. Arterial occlusion developed in 7 patients, early in the course of active SLE and mainly affecting peripheral arteries in 4, later and affecting coronary arteries in three. In two patients, both arterial and venous manifestations occurred simultaneously or successively. A circulating anticoagulant with antiprothrombinase activity was present in 8 (61 percent) of the 13 patients with thromboembolic manifestations, as compared to only 21 percent of those without such manifestations, a highly significant (p less than 0.001) difference.

Arteries↗
PubMed1979

The in vitro migration of murine fetal liver cells to thymic rudiments.

The migration of murine fetal liver cells to thymus rudiments was studied in vitro using a migration under agar technique. There appeared to be a minor population that migrated specifically to the thymus from the age of 10 to 14 days of gestation. The specificity of migration was demonstrated in 12-day fetal liver cells by a series of competition studies. The ability of these cells to colonize a thymus rudiment was shown by further incubation after invasion of the epithelial thymus rudiments: small colonies of lymphoid cells were present in invaded tissue but absent from uninvaded control tissue. At 13 to 14 days of gestation, there appeared an additional population that migrated specifically to the spleen, as demonstrated, again, with a competition protocol. Studies with avian and human tissue as attractants in the same system showed that migration was specific to the thymus and did cross species barriers. This observation was used to demonstrate a similar attractant activity in cell-free conditioned medium from human thymus epithelial cultures, and to demonstrate the absence of such a cell-attractant factor in the conditioned medium from the thymus of a child with previously documented severe combined immunodeficiency disease.

Animals↗