Dynamics of cytokine mRNA expression and fecal biomarkers in school-children undergoing a double-blind placebo-controlled food challenge series.

Background: There is need for prognostic markers for symptomatic food allergy since current diagnostic methods are insufficient and/or time and labor consuming.

Objective: To estimate the cytokine mRNA profiles in peripheral blood mononuclear cells (PBMC) before and after a double-blind placebo-controlled food challenge series in schoolchildren with suspected allergy to milk, egg or cod and in healthy controls. Analyses of fecal inflammatory biomarkers before and after the challenge were included.

Induction of cell death in T lymphocytes by invasin via beta1-integrin.

Ligand binding to beta1-integrins exerts multiple effects on cells of the immune system including adhesion, spreading, haptotaxis and costimulation of T cells activated by anti-CD3. Here we show that a high-affinity ligand for beta1-integrins, the invasin (Inv) protein of Yersinia pseudotuberculosis, can induce cell death in T lymphocytes via a rapid process. Partially purified native Inv protein and an Inv fusion protein caused apoptotic/necrotic caspase-independent cell death in T lymphocytes as determined by phosphatidylserine exposure on the cell surface, uptake of propidium iodide, labeling of DNA strand breaks and presence of DNA ladder.

T lymphocyte expression of thrombospondin-1 and adhesion to extracellular matrix components.

The mechanisms controlling the formation of pseudopodia and other active cell edges in T lymphocytes are not understood. We show here that T lymphocytes express thrombospondin-1 (TSP-1). TSP-1 in T lymphocytes has a high turnover as shown by the fact that brefeldin and monensin rapidly increase while cycloheximide tend to decrease the cellular TSP-1 content.

Cytocidal and apoptotic effects of the ClyA protein from Escherichia coli on primary and cultured monocytes and macrophages.

Cytolysin A (ClyA) is a newly discovered cytolytic protein of Escherichia coli K-12 that mediates a hemolytic phenotype. We show here that highly purified ClyA and ClyA-expressing E. coli were cytotoxic and apoptogenic to fresh as well as cultured human and murine monocytes/macrophages.

Yersinia invasin, a bacterial beta1-integrin ligand, is a potent inducer of lymphocyte motility and migration to collagen type IV and fibronectin.

The Yersinia pseudotuberculosis invasin protein was found to be a potent inducer of pseudopodia formation and chemotactic and haptotactic migration in human T lymphocytes. Checkerboard analysis confirmed that migration was directional. The Yersinia invasin triggered migration of otherwise poorly migratory normal T cells on fibronectin and in particular on collagen type IV, and augmented the migration of leukemic T cell lines on these components.

Fibronectin and lymphocytes in inflammatory tissue. Studies of blood and synovial fluid lymphocytes from patients with rheumatoid arthritis and other inflammatory arthritides.

Lymphocytes infiltrating tissues under chronic inflammatory conditions are often surrounded by deposits of fibronectin. We have studied the possibility that this reflects capacity of lymphocytes to synthesize fibronectin and compared lymphocytes from blood and synovial fluid with respect to fibronectin interactions. In vitro activated blood lymphocytes exhibited synthesis of a fibronectin-like molecule.

Characterization of collagen binding lymphocyte membrane molecules.

Blood lymphocytes can adhere to two-dimensional collagen substrata. The lymphocyte plasma membrane contains 130 and 55 kd components with collagen-bindings capacity as well as high molecular weight collagen binding component (greater than 200 kd) pointing to the possibility that these molecules mediate lymphocyte adhesion to collagen. The 55 kd and the high molecular weight component also react with anti-fibronectin antibodies.

Collagen receptor on T lymphocytes and the control of lymphocyte motility.

Human lymphocytes, freshly isolated from blood, were allowed to settle on surfaces coated by collagen type 1, fibronectin, laminin, IgG or albumin at different concentrations. In separate cultures the lymphocytes were also exposed to these proteins in soluble form. The lymphocytes, predominantly T cells, attached to two-dimensional collagen substrata both in the presence and absence of serum but did not adhere or adhered poorly to substrata coated with fibronectin, laminin, IgG and albumin.

[Long-term study of patients with active chronic hepatitis treated with leukocyte interferon].

Seven patients with active chronic hepatitis who received Interferon Alfa showed a marked humoral and histological improvement one year after the treatment was concluded, in 3 patients the hepatic histology was almost normal, 2 evolved to a persistent chronic hepatitis and only one showed deterioration. These results differed from those obtained immediately after the treatment (p 0.05).

Induction of motility and alteration of surface membrane polypeptides in lymphocytes by contact with autologous and allogeneic fibroblasts.

Contact with cultured fibroblasts induced and maintained motile behavior in autologous and allogeneic human lymphocytes. After 3 h of contact with fibroblasts, 50 +/- 19% of the autologous lymphocytes were motile and after 24 h the corresponding figure was 49 +/- 18%. On a plastic surface the number of motile lymphocytes in the same individuals generally persisted below 15%.