Identification of the IgG binding site of the human low affinity receptor for IgG Fc gamma RII. Enhancement and ablation of binding by site-directed mutagenesis.

Fc receptor-antibody interactions are key mechanisms through which antibody effector functions are mediated. The low affinity receptor for IgG, Fc gamma RII, is expressed on most hematopoietic cells, and through the binding of immune complexes mediates a large spectrum of biological responses vital for resistance to infection and the regulation of immunity. In this study the key residues of human Fc gamma RII involved in the interaction with IgG1 have been identified.

Use of the 5'-flanking region of the mouse perforin gene to express human Fc gamma receptor I in cytotoxic T lymphocytes.

Expression of the gene encoding the cytolytic granule protein perforin is restricted to cytotoxic lymphocytes. To undertake a functional analysis of the immediate 5'-promoter region of the mouse perforin gene, we transiently transfected mouse perforin promoter-chloramphenicol acetyltransferase (CAT) reporter gene constructs into cytotoxic T, T lymphoid, B-lymphoid, and nonlymphoid cell lines. The transcriptional activity of the perforin promoter was restricted to cytotoxic lymphocytes.

The production and preclinical characterization of a chimeric anti-breast-cancer antibody, cBC2.

A chimeric (mouse-human) BC2 antibody (cBC2) was produced which may be used in the diagnosis and treatment of breast cancer. The BC2 variable region genes were amplified by polymerase chain reaction (PCR), using oligonucleotide primers homologous to the framework sequences of mouse VH and V kappa genes. The PCR products were used to create cBC2 expression vectors containing the mouse BC2 VH and V kappa and human constant region (IgG1 and K) genes.

Increased ascitic fluid prorenin in the ovarian hyperstimulation syndrome.

Three patients developed severe ovarian hyperstimulation syndrome (OHS) as a complication of ovarian hyperstimulation for in vitro fertilization. These patients presented with ovarian enlargement, vascular volume depletion, pleural effusions, and exudative ascites. A unique feature of the ascites in OHS was the markedly elevated renin concentration, the majority of which was prorenin.

Polymorphism at the mouse Thb locus.

Mouse ThB is a 15,000 M(r) glycosyl phosphatidyl inositol anchored cell surface glycoprotein that shares amino acid homology with Ly-6 molecules; the gene is closely linked to Ly-6 on chromosome 15. The Thb locus has two alleles, Thbh and Thbl, which control the level of expression of ThB molecules on thymocytes (as shown herein) and on splenic B cells, and is therefore different from the usual polymorphisms of other Ly loci which give an all or none serological reaction. The reason for the expression polymorphism is unknown and could include a different protein structure in ThB molecules, altered glycosylation, or differences in transcriptional control.

Enhanced antitumour effects using a combination of two antibodies conjugated to different drugs.

The heterogeneity of tumour antigen expression, the differential sensitivity of individual cells to drugs and the use drug--antibody immunoconjugates with limited potency can limit the antitumour effects of immunoconjugate therapy. In this study we have used two different antibodies linked to two different drugs Melphalan (Mel) and Idarubicin (Ida), each with a different site action, to evaluate the potential of using cocktails of immunoconjugates. A series of drug combinations were screened for their synergistic activity in vitro using the inhibition of [3H]-thyrmidine uptake by E3 cells, and constructing isobolagrams: Mel plus Ida was the only combination found to be synergistic in vitro and this synergism extended to the drugs after conjugation to antibodies.

A phase I/II study of the intralesional injection of ricin-monoclonal antibody conjugates in patients with hepatic metastases.

A phase I/II study of the intralesional administration of ricin-labelled monoclonal antibodies was conducted in patients with hepatic metastases of gastrointestinal origin. The anti-carcinoembryonic antigen (CEA) antibody I-1 was conjugated to blocked ricin via a disulphide bridge. After a test dose of antibody, patients were injected with ricin-antibody conjugates under computed tomography (CT) guidance on two occasions 1 week apart.

Recombinant MUC 1 vaccinia virus: a potential vector for immunotherapy of breast cancer.

Breast cancer is considered as the major cause of mortality by cancer for women. Even if chemotherapy, radiotherapy and surgery have improved the life expectancy of patients bearing tumours, breast cancer is responsible for the death of 42,000 women per year in USA and 25,000 women in France. In this context, cancer vaccines may add an attractive alternative therapeutic strategy to the current existing treatments.

Cellular mucins: targets for immunotherapy.

Mucins are attracting great interest as potential targets for immunotherapy in the development of vaccines for cancers expressing Mucin 1 (MUC1) (e.g., breast, pancreas, ovary, and others) as there is (1) a 10-fold increase in the amount in adenocarcinomas; (2) an alteration in expression where they become ubiquitous, and (3) due to altered glycosylation, new epitopes appear on the cell surface that are absent in normal tissues.

Upregulation of complement regulators MCP (CD46), DAF (CD55) and protectin (CD59) in arthritic joint disease.

CD46, CD55 and CD59 are cell surface glycoproteins which are widely distributed on normal tissue, where they function in the prevention of complement-mediated damage. In this study we have investigated the altered expression of these molecules under inflammatory conditions both in vitro and in vivo. By using immunocytochemical techniques we demonstrated marked but disparate upregulation of these molecules in IL1-treated cartilage and in diseased cartilage from arthritic joints compared to normal cartilage in both humans and pigs.

Peptide binding sites recognized by anti-mucin (MUC2) monoclonal antibodies.

Multiple genes coding for human mucins have been identified (MUC 1-5) and here monoclonal antibodies (MoAb) to a gastrointestinal mucin--MUC2 are examined. The antibodies were made to a synthetic peptide representing a single repeat in the core protein of the variable number of tandem repeat region. Using the six-mer overlapping peptides synthesized on polyethylene pins, different binding sites were detected by five anti-MUC 2 MoAbs.

Anti-pig IgM antibodies in human serum react predominantly with Gal(alpha 1-3)Gal epitopes.

A major problem with pig-to-human-tissue xenograft studies is that humans have natural antibodies to pig cells; these antibodies would cause hyperacute rejection if pig tissues were xenografted to humans. Here we show that most of human IgM antibodies present in the serum of healthy donors and reactive with pig cells react with galactose in an (alpha 1-3) linkage with galactose--i.e.

Mucin 1 antigens in the serum and bronchial lavage fluid of patients with lung cancer.

Background: Lung cancer (LC) is the most common fatal malignancy, but there are no useful tumor markers for diagnosis or monitoring. Mucin 1 has an established role as a marker in other malignancies, but has undergone limited assessment in LC.

Methods: Serum from 86 patients with LC and 24 with benign pulmonary disease (BPD), and bronchial lavage fluid from 55 LC patients and 21 BPD patients were tested using the Mucin 1 assays mammary serum antigen (MSA) and cancer-associated serum antigen (CASA).

Heart rate and blood pressure variability in subjects exposed to simulated increases in gravity.

The effect of simulated increases in gravity (G) force on blood pressure and heart rate variability was investigated in seven normal healthy subjects using a man-carrying centrifuge. Subjects were exposed to G forces up to 3.6 times the gravity at the earth's surface (3.

Recombinant soluble human Fc gamma RII: production, characterization, and inhibition of the Arthus reaction.

A recombinant soluble form of human Fc gamma RII (rsFc gamma RII) was genetically engineered by the insertion of a termination codon 5' of sequences encoding the transmembrane domain of a human Fc gamma RII cDNA. Chinese hamster ovary cells were transfected with the modified cDNA and the secreted rsFc gamma RII purified from the tissue culture supernatant (to > 95%, assessed by SDS-PAGE) using heat aggregated human immunoglobulin G (IgG) immunoaffinity chromatography. The IgG-purified rsFc gamma RII was relatively homogeneous (approximately 31,000 M(r)) whereas the total unpurified rsFc gamma RII secreted into the tissue culture supernatant was heterogeneous relating to N-linked glycosylation differences.