ABSTRACT
A time-resolved immunofluorometric assay of the IgG specific for Toxoplasma gondii has been compared with two commercial methods, one automated enzyme linked fluorescent assay (VIDAS) and one automated colorimetric enzyme immunoassay (BEIA). The coefficients of variation were 3.4% and 7.4% within-assay (n = 12), and 9.2% and 8.1% between-assay (n = 10) for two sera at low and high concentrations of specific IgG. The regression lines obtained with 96 samples were y = 1.04x + 2.1 and y = 0.98x - 1.1. We also compared a time-resolved capture fluoroimmunoassay for Toxoplasma-specific IgM with a commercial immunoenzymatic assay (BEIA TOXO-M). The sensitivity and specificity were 100%, calculated from assays of 78 samples.
Subject(s)
Immunoglobulin G/analysis , Immunoglobulin M/analysis , Reagent Kits, Diagnostic , Toxoplasma/immunology , Animals , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Humans , Immunoenzyme TechniquesABSTRACT
The present paper describes the generation and characterization of anti-idiotypic monoclonal antibodies (Ab2 MAbs) produced against the MOv19 MAb (Ab1 MAb), which shows a restricted reactivity with human ovarian carcinoma. The Ab2 MAbs were produced by immunizing mice with MOv19 conjugated to syngeneic mouse red blood cells (MRBC). After the somatic hybridization, five Ab2 MAbs, designated Id19.1, Id19.2, Id19.3, Id19.4 and Id19.5, were selected by a sandwich assay on the basis of their specific reactivity to the MOv19 MAb, but not to the isotype-matched MAb used as a control. A complete cross-inhibition between these 5 MAbs was observed, indicating that they recognize overlapping idiotopes on MOv19. The Ab2/antigen relationship of two Ab2 MAbs (Id19.1 and Id19.2) was investigated by competition experiments on a relevant tumor target cell line. We showed that both Ab2 MAbs were able to interfere with the antigen binding capacity of 125I-MOv19. Moreover, Id19.1 was able partially to inhibit the binding of the purified radiolabelled antigen recognized by the MOv19 MAb (125I-CaMOv19) on insolubilized MOv19. To investigate further whether the Ab2 MAb is the "internal image" of CaMOv19, Id19.1 was used as immunogen with the aim to induce an anti-CaMOv19 response. The antisera tested by indirect solid-phase radioimmunoassay (RIA) on the Ab2 MAb and the irrelevant isotype-matched control MAb revealed an anti-anti-idiotypic response (Ab3). However, no Ab3 antibodies with Ab1-like specificity (Ab1') were found in the immune sera, as assessed by testing the antisera both in indirect immunofluorescence (IF) and solid-phase RIA on CaMOv19-positive target cell lines.
Subject(s)
Antibodies, Anti-Idiotypic , Antibodies, Monoclonal , Carrier Proteins/analysis , Carrier Proteins/immunology , Ovarian Neoplasms/chemistry , Receptors, Cell Surface/analysis , Animals , Antibody Specificity , Cell Line , Female , Folate Receptors, GPI-Anchored , Humans , Mice , Mice, Inbred BALB C/immunology , Radioimmunoassay , Receptors, Cell Surface/immunologyABSTRACT
We previously reported that the expression on the primary tumour of the antigen CaMBr8 was related to a short survival, attributable either to higher tumour aggressiveness or a poor response to oophorectomy. To further verify the CaMBr8 prognostic value, we analysed retrospectively 862 breast cancer patients with a 19 year follow-up. In this series, CaMBr8 expression was found to be associated to some negative prognostic factors (premenopausal status, lymphnode invasion, a high number of mitosis and HER-2/neu oncoprotein expression), but had no influence on the patients' survival. Direct association with a poor prognosis was only evident in patients with lobular or mixed breast carcinoma, which however represent only a small fraction of the total breast cancers. Another possibility was that CaMBr8 could identify a subgroup of patients which did not respond to hormone therapy. To verify this hypothesis we evaluated on a second series of 116 patients the relationship between CaMBr8 expression and hormone-receptor levels. A negative association emerged which was also observed in vitro in the human breast cancer line MCF-7 treated with Sodium Butyrate, a differentiation inducer, which reduced hormone-receptor levels and increased CaMBr8 expression. In conclusion, the longer survival of CaMBr8 negative tumour patients observed in the initial study, was probably related to a better response to oophorectomy, due to the hormone-receptor level of their tumours.
Subject(s)
Antigens, Neoplasm/biosynthesis , Biomarkers, Tumor/biosynthesis , Breast Neoplasms/immunology , Breast Neoplasms/mortality , Adult , Follow-Up Studies , Gene Expression , Humans , In Vitro Techniques , Middle Aged , Prognosis , Prospective Studies , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Retrospective Studies , Survival AnalysisABSTRACT
The production and characterization of two new monoclonal antibodies (MAbs), designated MAR4 and MAR5, raised against the partially purified alpha 5 beta 1 integrin, are described. The reactivity of these 2 MAbs on tumor cell lines indicated that they reacted on all the cells expressing the beta 1 subunit independently of the alpha 5 expression. Both MAbs were found to immunoprecipitate on 3 cell lines, a protein of 120 KD corresponding to the molecular weight be the beta 1 chain, in addition to proteins of other MW corresponding to the alpha subunits differentially expressed by these cells. The cross-competition experiments showed that MAR4 and MAR5 recognize the same epitope. These 2 MAbs seem to be useful reagents for the characterization of the VLA expression in tumor cells.
