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V Liu

Publications and source records attributed to V Liu.

25 records · Page 2Linked to original sources
PubMed1987

A monoclonal antibody to squamous cell carcinoma.

Monoclonal antibody 17.13.Cl.10 is a murine IgM kappa monoclonal antibody (Mab) that stains frozen section squamous cell carcinoma (SCC) homogeneously and intensely with a sensitivity greater than 98%, including 106/107 SCC specimens from the head and neck. It was produced using a human laryngeal SCC as immunogen and screened using frozen section human tissue. Monoclonal antibody 17.13.Cl.10 faintly stains the basal layer of normal squamous epithelium, does not stain normal organ tissue other than myoepithelial cells, and reacts with few non-SCC tumors. It, therefore, may be a useful adjunct to standard histopathologic criteria for the diagnosis of SCC. It may prove helpful in the investigation of tumor-associated antigens. Despite major technical and immunologic problems, monoclonal antibodies to functional tissue-specific tumor-associated antigens have the potential to play a major role in imaging and in treatment in the future.

Animals↗
PubMed1985

Monoclonal antibodies as structural probes for oligomeric human interferon-gamma.

Monoclonal antibodies (MAb) B1 and B3, specific for human interferon-gamma (IFN-gamma) failed to immunoprecipitate heat-inactivated human IFN-gamma in solution. However, both MAb retained some reactivity with denatured IFN-gamma immobilized on vinyl plates. The two MAb have been employed in a sensitive immunoradiometric assay (IRMA). In this IRMA one MAb was bound to polystyrene beads and used as immunoadsorbent. The second MAb, labeled with 125I, was used as the tracer to quantitate the amount of IFN-gamma bound to the immobilized MAb. Addition of unlabeled MAb B1 did not inhibit the binding of 125I-labeled MAb B3 (and vice versa), indicating that the two MAb react with two different and nonoverlapping epitopes. Yet, when the same MAb was used in IRMA as both immunoadsorbent and tracer, the amount of labeled MAb bound to a given concentration of natural or E. coli-derived recombinant human IFN-gamma was very similar as with two different MAb, indicating that a single IFN-gamma molecule must have two or more identical binding sites for each of the two MAb. These findings show that biologically active natural and recombinant human IFN-gamma exist in oligomeric form.

Antibodies, Monoclonal↗
PubMed1984

Use of monoclonal antibodies as sensitive and specific probes for biologically active human gamma-interferon.

Mouse monoclonal antibodies B1 and B3 are specific for natural and Escherichia coli-derived recombinant human gamma-interferon (IFN-gamma). The two antibodies recognize different epitopes of the IFN-gamma molecule and do not compete with each other's binding. We have used these two antibodies to construct a solid-phase, sandwich immunoradiometric assay for human IFN-gamma. Purified antibody B1 was coated on polystyrene beads (0.64 cm in diameter) and used as the solid-phase immunoadsorbent and antibody B3 was labeled with 125I and used as tracer. This assay can be completed in about 4 hr and is capable of detecting IFN-gamma levels in human serum or tissue culture fluids as low as 0.1 NIH reference unit/ml. Recombinant human IFN-gamma derived from E. coli was detectable at a concentration of 0.02 ng/ml. The assay appears to be specific for the biologically active forms of IFN-gamma, since after exposure to pH 2, 37 degrees C, or 56 degrees C, biological activity and reactivity in the immunoradiometric assay decreased in parallel. The immunoradiometric assay can be employed for the analysis of the structural characteristics of the human IFN-gamma molecule.

Animals↗
PubMed1983

Should lumbar puncture be routinely performed in patients with suspected bacteremia?

In an attempt to develop a rational basis for performing lumbar puncture in sepsis workups, the hypothesis was tested that, for each of eight variables with a known association with bacteremia, the frequencies for patients having bacterial meningitis would be significantly greater than those in patients having bacteremia alone. In a one-year period, 168 lumbar punctures were performed in children having a mean age of 7.3 months. Patients were assigned to four groups: bacterial meningitis, bacteremia only, aseptic meningitis, and normal. Mean age, frequencies of symptoms, clinical appearances, ethnic groups, and sex ratio were determined for all groups. Frequencies of eight variables were determined and compared between Groups I and II.Results indicated that frequencies were not significantly different for groups I and II and that lethargy and petechiae, although distinguishing between groups I and IV, did not distinguish among the three groups having serious disease. It was concluded that since one cannot distinguish among groups having serious disease, all such patients suspected of sepsis should undergo lumbar puncture.

Adolescent↗
PubMed1983

Radioimmunometric assay for a monoclonal antibody-defined tumor marker, CA 19-9.

We describe a solid-phase radioimmunometric sandwich assay for a new tumor marker defined by a monoclonal antibody (19-9). This antibody reacts with a carbohydrate antigenic determinant (CA 19-9) found at low concentrations in sera from healthy individuals but frequently increased in sera from patients with adenocarcinomas. The assay is sensitive and simple to perform. It requires duplicate 100-microL samples and may be performed in 6 h. The concentration of CA 19-9 in samples is determined by reference to a standard curve, which is essentially linear from 0 to 120 arbitrary units/mL. The average CV is approximately 10% in the range of 5.8 to 120 units/mL. The minimum detectable dose is 1.4 units/mL and analytical recovery of CA 19-9 is 97.6 to 100.6%. The average concentration of CA 19-9 in sera from 1020 healthy individuals was 8.4 (SD 7.4) units/mL; only 0.6% of such sera had concentrations greater than 37 units/mL. The assay has high specificity (98.5%), even among patients with benign diseases, and has high sensitivity (up to 79%) for patients with gastrointestinal adenocarcinomas, especially those of the pancreas.

Adenocarcinoma↗