PubMed Health⌕ Search

Biomedical subjects

R Gonzalez-Cabello

Publications and source records attributed to R Gonzalez-Cabello.

At least 19 recordsLinked to original sources
PubMed1990

[Immunomodulator effect of silymarin therapy in chronic alcoholic liver diseases].

The effects of the hepatoprotective, antioxidant drug silymarin (Legalon) on some cellular immune parameters of patients with histologically proven chronic alcoholic liver disease were studied in a six month double blind study. The lectin induced proliferative activity of the lymphocytes got enhanced, the originally low T cell percentage and the originally high CD8+ cell percentage have been normalized, the antibody-dependent and natural cytotoxicity of the lymphocytes decreased during silymarin therapy. All these changes were significant, while in the placebo group no significant changes occurred, except for a moderate elevation of the T cell percentage. Thus, the immunomodulatory activity of silymarin might be involved in the hepatoprotective action of the drug and improves the depressed immunoreactivity of the patients.

Adjuvants, Immunologic↗
PubMed1989

A simple assay for tumor necrosis factor using HEp-2 target cells.

We developed a sensitive bioassay system for the determination of tumor necrosis factor-alpha (TNF) using HEp-2 adherent human epipharynx carcinoma cells as targets. TNF from separated human monocytes was triggered by lipopolysaccharide (LPS). In a 24 hr 3H-thymidine incorporation assay, TNF-like activity was seen to reproducibly destroy radiolabeled target cells, i.e., inhibits thymidine incorporation and causes detachment of adherent HEp-2 cells. HEp-2 cells were insensitive to human interleukin-1 (IL-1) and interleukin-2 (IL-2). In contrast, human interferon-alpha and gamma were also cytotoxic for target cells. Monocyte supernatants stimulated by LPS, however, failed to contain detectable amounts of interferons.

Biological Assay↗
PubMed1986

Indomethacin abrogates the suppression by cyclosporin A of lectin-dependent cell-mediated cytotoxicity to HEp-2 cells.

The effects of cyclosporin A, prostaglandin E1 and indomethacin were studied on lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 human epipharynx carcinoma target cells. LDCC activity by human peripheral blood lymphocytes was evaluated by detachment from the monolayer of [3H]thymidine-prelabelled HEp-2 cells in a 24-h assay at 50:1 effector:target cell ratio in the presence of 25 micrograms/ml concanavalin A. Under these conditions, but without concanavalin A, considerable natural cell-mediated cytotoxicity was not elicited although LDCC was significantly augmented in the presence of concanavalin A. Addition of both cyclosporin A (0.1, 1.0 or 10 micrograms/ml) and prostaglandin E1 (10(-8), 10(-7) or 10(-6) M) dose-dependently suppressed LDCC activity. Indomethacin (0.1, 1.0 or 10 micrograms/ml) did not in itself influence LDCC although suppression of LDCC by cyclosporin A, but not prostaglandin E1, was abrogated in the presence of indomethacin. Similar to indomethacin, acetyl salicylic acid also reversed the inhibition of LDCC by cyclosporin A. In parallel experiments, cyclosporin A elicited a more than two-fold increase of prostaglandin E production under LDCC assay conditions as measured by radioimmunoassay. Contrary to LDCC, depression of concanavalin A induced blastogenesis by cyclosporin A was not influenced by indomethacin, suggesting that the inhibition by cyclosporin A of LDCC and concanavalin A-induced blastogenesis proceed via different mechanisms.

Carcinoma, Squamous Cell↗
PubMed1986

Immunomodulation in autoimmune diseases.

Systemic autoimmune diseases are generally treated with immunosuppressive agents. In some instances immunomodulatory agents have shown promise in the treatment of certain types of autoimmune disorders. The in vitro and/or in vivo effects of some of these agents (glutaurine, ketoconazole, gutimine and its derivative) are demonstrated. Glutaurine exerts moderate immunostimulating activity, but fails to influence the clinical course of systemic lupus erythematosus. Although ketoconazole suppresses immune responses in vitro, it does not influence cellular reactivity of patients in vivo. The immunostimulatory activity of gutimine and its derivative (T 001) have been demonstrated in vitro, and need to be tested also in vivo.

Adjuvants, Immunologic↗
PubMed1986

Depressed lectin-dependent and enhanced antibody-dependent cell-mediated cytotoxicity in patients with stage I cancer of the larynx.

Lectin-dependent cell-mediated cytotoxicity (LDCC) of peripheral blood mononuclear cells (PBMC) from patients with stage I cancer of the larynx (LC) was evaluated using human adherent 3H-TdR-prelabeled HEp-2 carcinoma cells as targets at 50:1 effector-target ratio with 25 micrograms/ml concanavalin A (Con A) in a 24-hour assay. Under these conditions, but without Con A, no considerable natural cell-mediated cytotoxicity (NCMC) was performed by PBMC either from control or from LC donors. Depressed levels of LDCC, but augmented ADCC to chicken red blood cells were detected in LC patients. Natural killer activity to K562 targets was not different from that of control subjects. In parallel studies, normal Con A-induced blastogenesis and B cell counts, low T, and active T cell counts, as well as high Leu-11a+ cell counts were detected in patients with LC. The relationship between depressed LDCC and low T, and active T cell counts, and enhanced ADCC and high Leu-11a+ cell counts is suggested in stage I LC patients.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1986

Lectin-dependent cell-mediated cytotoxicity and blastogenesis by large granular-enriched and depleted lymphocytes.

The role of larger granular-enriched and depleted lymphocytes was studied in lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 human epipharynx carcinoma target cells. LDCC was evaluated by detachment from the monolayer of 3H-thymidine-prelabelled HEp-2 cells in a 24 h assay at effector-target cell ratios of 25:1 and 50:1 in the presence of 25 micrograms/ml concanavalin A (Con A). Under the aforementioned conditions but in the absence of Con A natural cell-mediated cytotoxicity (NCMC) was not found. However, cytotoxicity was significantly augmented in the presence of Con A (= LDCC) using human peripheral blood mononuclear cells (PBMC) as effectors. Large granular lymphocytes (LGL), which show high natural killer (NK) activity to K 562 target cells, failed to be cytotoxic against HEp-2 targets similar to large granular depleted lymphocytes (LGL-DL). On the other hand, LGL caused only a slight LDCC; whilst LGL-DL induced strong LDCC activity towards HEp-2 targets. In comparison to LDCC using LGL-DL as effector cells, LGL and LGL-DL mixed at a ratio of 1:2, and added to target cells, had no major effect on LDCC, while a lower level of LDCC was observed at LGL/LGL-DL ratios of 1:1, and 2:1, suggesting the dilution of LGL-DL, potential effectors of LDCC to HEp-2 cells, rather than a specific regulatory role of LGL in LDCC. In parallel studies, the proliferation of LGL-DL in response to Con A was less than that observed with PBMC or LGL. The response could be restored by replacing half of LGL-DL per culture with an equal number of LGL, or by the addition of 10% monocytes. Significant functional differences between LGL and LGL-DL in LDCC as well as in Con A-induced blastogenesis are suggested.

Cell Line↗
PubMed1985

Contrasting effects of RNA and protein synthesis blocking on natural and lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells.

In this study, earlier observations concerning the independence of both natural (NCMC) and lectin-dependent cell-mediated cytotoxicity (LDCC) from DNA synthesis have been confirmed. In addition, blocking of RNA synthesis by actinomycin D and of protein synthesis, reversibly by puromycin (PM) and irreversibly by emetine (EM) had different effects on NCMC and LDCC against 3H-thymidine-prelabeled HEp-2 target cells. Similarly to the Con A-induced proliferation of lymphocytes, LDCC activity was also inhibited by blocking of RNA and protein synthesis. NCMC to HEp-2 target cells was not affected by blocking of RNA synthesis, while both PM and EM strongly enhanced NCMC activity.

Cell Adhesion↗
PubMed1985

Depressed lectin-dependent cell-mediated cytotoxicity against HEp-2 cells in patients with metastasizing solid tumour.

Lectin-dependent cell-mediated cytotoxicity (LDCC) of peripheral blood mononuclear cells (PBMC) from tumour patients was evaluated using human adherent 3H-TdR-prelabelled HEp-2 epipharynx carcinoma cells as targets at 50:1 effector-target cell ratio with 25 micrograms/ml concanavalin A (Con A) in a 24h assay. PBMC of nine patients with metastasizing solid tumour failed to exert cytotoxicity against HEp-2 targets. In contrast, increased survival (decreased detachment from the monolayer) of HEp-2 cells was observed in the presence of PBMC from tumour patients that was significantly enhanced by addition of Con A during LDCC assay.

Cell Line↗
PubMed1985

Stimulation by thymopoietin oligopeptides of lectin-dependent cell-mediated cytotoxicity in patients with systemic lupus erythematosus.

The effect of thymopoietin penta- (TP-5), tetra-(TP-4), and tripeptides (TP-3) was studied on the depressed lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 target cells by peripheral blood mononuclear cells from patients with active systemic lupus erythematosus (SLE). LDCC activity was evaluated by detachment from the monolayer of 3H-thymidine-prelabelled HEp-2 cells in the presence of concanavalin A (Con A). While 10(-5)M TP-3 moderated the depression, 10(-5) M TP-5 strongly enhanced LDCC activity in SLE patients up to the normal level. On the other hand, LDCC activity by normal donors was not influenced by TP-3 and TP-5. TP-4 had no major effect either in control or in SLE patients. In parallel experiments none of the thymopoietin peptides affected the Con A-induced suppressor activity on the blastogenesis of lymphocytes. A selective immunostimulatory effect of TP-3 and TP-5 on the generation of LDCC effector cells in patients with SLE is suggested.

Concanavalin A↗
PubMed1985

Effect of histamine-receptor blocking on human natural and lectin-dependent cell-mediated cytotoxicity against adherent HEP-2 cells.

The effect of histamine (H) and H1-, H2-receptor blocking agents was studied on natural (NCMC) and lectin-dependent cell-mediated cytotoxicity (LDCC) of peripheral blood lymphocytes (PBL) from eight healthy subjects on HEP-2 adherent human epipharynx carcinoma target cells. Cytotoxicity was measured by detachment from the monolayer of 3H-TdR-prelabelled HEp-2 cells. LDCC was evaluated in a 24 h assay with a Concanavalin A (Con A) dose of 25 micrograms/ml at 50:1 effector-target cell ratio. Under these conditions, but without Con A, considerable NCMC was not elicited by normal lymphocytes. The presence of histamine and the H2-receptor blocker cimetidine resulted in a significant NCMC to HEp-2 cells. On the contrary, histamine and cimetidine reduced LDCC. The H1-receptor blocker clemastine had no significant effect on either NCMC or LDCC to HEp-2 targets. The possible involvement of H2-receptor bearing cells in the regulation of cytotoxicity to HEp-2 cells is suggested.

Cell Adhesion↗
PubMed1984

Effector activity of OKT4+ and OKT8+ T-cell subsets in lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells.

The role of OKT4+ and OKT8+ T-cell subsets was studied in lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 human epipharynx carcinoma target cells. LDCC was evaluated by detachment from the monolayer of [3H]thymidine prelabeled HEp-2 cells in a 24-hr assay with a concanavalin A (Con A) dose of 25 microgram/ml at effector:target cell ratios of 5:1, 25:1, and 50:1. Under these conditions but without Con A considerable natural cell-mediated cytotoxicity (NCMC) was not elicited; however, the cytotoxicity was significantly augmented in the presence of Con A (=LDCC) by sheep erythrocyte rosette-forming T lymphocytes and by both OKT4+ and OKT8+ T-cell fractions. LDCC activity by isolated OKT8+ T cells was superior to that by OKT4+ T cells and unfractionated T lymphocytes. By contrast, addition of either OKT4+ or OKT8+ T cells together with unfractionated T lymphocytes, or OKT4+ and OKT8+ T cells mixed at ratios of 1:1, 1:2, and 2:1, to target cells did not result in major differences in comparison of LDCC activities by these mixed effector cell populations with each other or with that by unfractionated T lymphocytes. Parallel studies were carried out to determine the effect of OKT4+ and OKT8+ T-cell subsets on the Con A-induced proliferation of peripheral blood mononuclear cells (PBMC). While OKT8+ T cells inhibited the mitogenic response to Con A, OKT4+ T lymphocytes had no major effect. A higher responsiveness of the OKT8+ to OKT4+ T-cell subset in LDCC to HEp-2 targets and in Con A-induced lymphocyte proliferation is suggested.

Antibodies, Monoclonal↗
PubMed1984

Depressed effector activity of OKT4+ and OKT8+ T cell subsets in lectin-dependent cell-mediated cytotoxicity to HEP-2 cells in patients with systemic lupus erythematosus.

The role of OKT4+ and OKT8+ T cell subsets was studied in depressed lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 target cells by peripheral blood mononuclear cells (PBMC) from patients with active systemic lupus erythematosus (SLE). LDCC activity was evaluated by detachment from the monolayer of 3H-TdR-prelabelled HEp-2 cells in a 24 hr assay at 50:1 effector-target cell ratio in the presence of 25 micrograms/ml concanavalin A (Con A). Decreased levels of LDCC were performed by all studied effector cell populations of SLE patients, including both OKT4+ and OKT8+ T cell fractions. LDCC by isolated OKT8+ T cells was superior to that by OKT4+ and unfractionated T lymphocytes from all healthy and SLE subjects. This suggests that the defect of LDCC activity in SLE did not affect the inherently higher LDCC effector activity of OKT8+ to OKT4+ cells. In parallel studies a reduced proliferation of PBMC in response to Con A and failure of OKT8+ T cells to suppress Con A-induced blastogenesis was observed in patients with SLE.

Adult↗
PubMed1983

Depressed lectin-dependent cell-mediated cytotoxicity against adherent HEP-2 cells in patients with carcinoma of the uterine cervix.

Lectin-dependent cell-mediated cytotoxicity of peripheral blood mononuclear cells from patients with uterine cervix carcinoma was evaluated using human adherent 3H-TdR-prelabeled HEp-2 epipharynx carcinoma cells as targets at a 50:1 effector-target cell ratio with 25 micrograms concanavalin A/ml in a 24-h assay. Peripheral blood mononuclear cells from 13 patients with cervical carcinoma in stage IV failed to exert cytotoxicity against HEp-2 targets. In contrast, an increased survival (decreased detachment from the monolayer) of HEp-2 cells was observed in the presence of peripheral blood mononuclear cells from patients, this being significantly enhanced by addition of concanavalin A during the lectin-dependent cell-mediated cytotoxicity assay.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1983

Effect of Fc receptor blocking on human natural and lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells.

The effect of Fc receptor (FcR) blocking by aggregated human gamma-globulin (AGG) was studied on natural (NCMC) and lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 human epipharynx carcinoma target cells. Cytotoxicity was measured by detachment from the monolayer of [3H]TdR-prelabelled HEp-2 cells. LDCC was evaluated in a 24 h assay at 50:1 effector-target cell ratio in the presence of 25 micrograms/ml concanavalin A (Con A). Under these conditions but without Con A considerable NCMC was not elicited by normal lymphocytes. FcR blocking by AGG treatment of effector cells resulted in a significant NCMC activity to HEp-2 targets. In contrast, AGG treatment profoundly depressed LDCC. Monocyte depletion of effector cells had no major influence on the effect of AGG on NCMC and LDCC activities. An interference of FcR blocking by AGG and LDCC in response to Con A is suggested.

Cell Line↗
PubMed1983

Human lectin-dependent T cell-mediated cytotoxicity against Hep-2 cells.

A sensitive method for human lectin-dependent cell-mediated cytotoxicity (LDCC) is presented using HEp-2 adherent human epipharynx carcinoma cells as targets. Cytotoxicity was evaluated by detachment from the monolayer of 3H-TdR-prelabelled HEp-2 cells. Maximal LDCC was obtained in a 24 h assay with a Con A dose of 25 micrograms/ml for 50 : 1 effector-target cell ratio requiring only 2500 target cells per well. Testing of five different lymphocyte fractions: peripheral blood mononuclear cells (PBMC), monocyte-enriched adherent cells (AC), monocyte-depleted non-adherent cells (non-AC), T and non-T lymphocytes as effector cells from 25 normal individuals, suggests that LDCC to HEp-2 targets is mediated by T lymphocytes.

Cells, Cultured↗
PubMed1983

Stimulation of lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells by carrageenan.

The effect of carrageenan (CGN) was studied on lectin-dependent cell-mediated cytotoxicity (LDCC) against adherent HEp-2 human epipharynx carcinoma target cells. Cytotoxicity was measured by detachment from the monolayer of 3H-TdR pre-labelled HEp-2 cells. LDCC was evaluated in a 24 h assay at 50:1 effector-target cell ratio in the presence of 25 micrograms/ml concanavalin A (Con A). Under these conditions but without Con A considerable cytotoxicity was not elicited by peripheral blood mononuclear cells (PBMC). Addition of CGN to the system significantly increased LDCC to HEp-2 targets. Monocyte depletion of effector cells had no major influence to the effect of CGN on LDCC activity. In parallel studies CGN also enhanced the Con A-induced proliferation of PBMC.

Carrageenan↗
PubMed1982

Depressed natural and lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells in patients with systemic lupus erythematosus.

Natural cell-mediated cytotoxicity /NCMC/ was evaluated using human adherent 3H-thymidine-prelabelled HEp-2 epipharynx carcinoma cells as targets at 50:1 effector-target cell ratio in a 24 hr assay. For lectin-dependent cell-mediated cytotoxicity /LDCC/ studies cultures contained also 25/micrograms/ml concanavalin A /Con A/. Peripheral blood mononuclear cells /PBMC/ of nine patients with active systemic lupus erythematosus /SLE/ failed to exert NCMC or LDCC against HEp-2 targets. In contrast, an increased adherence /decreased detachment from the monolayer/ of HEp-2 target cells was observed in the presence of PBMC from SLE patients that was further promoted by the addition of Con A during LDCC assay.

Adolescent↗