Diagnostic immunology最新文献

In 13 women with premature follicular depletion (PFD) the concentration of T and B lymphocytes, T-cell subpopulation, and serum immunoglobulins was determined. Intending to study only women where no obvious cause for PFD existed, including autoimmune disease, five women were excluded because of significant titers of microsomal antibodies or antinuclear antibodies. In the remaining eight women a reduction in the percent of OKT4 (helper) lymphocytes (42.8 +/- 66 vs 50.7 +/- 3.7, P less than 0.005), the ratio of OKT4/OKT8 (suppressor/cytotoxic) lymphocytes (0.96 +/- 0.27 vs 1.6 +/- 0.25, P less than 0.001), and serum concentration of IgA (124 +/- 53 vs 210 +/- 81.5 mg/dl, P less than 0.01) were found compared to a control population. The concentration of T and B lymphocytes, IgG, IgM, and the cutaneous reactivity to mumps and candida antigens were similar in the two populations. It is hypothesized that a mild immune deficiency may predispose to PFD.

Rheumatoid factors were isolated for immunochemical study by a simple procedure based on immunoadsorption after dissociation of immune complexes. A monoclonal IgA that was not detectable in the patient's unseparated serum was thus demonstrated in one case of hypergammaglobulinemic purpura whereas polyclonal anti-IgG antibodies were isolated in several patients with autoimmune diseases.

The breakdown products of the third component of complement in approximately 400 samples were measured by rocket immunoelectrophoresis and two-dimensional electrophoresis using the method of Brandslund et al [3]. It was confirmed that the measurement of the C3d level provides useful information on increased C3 consumption irrespective of the synthetic rate. Furthermore, three subfragments with C3d but without C3c antigenicity were distinguished, which were designated as C3d1, C3d2, and C3d3. The subfragment C3d3 which migrated to the most anodal side was a predominant component in the plasma from patients with autoimmune diseases. Little C3d3 subfragment was detected in normal plasma and in normal sera incubated in vitro for 24 hr. Even in the normal sera converted completely in vitro which contained little intact C3, only a limited amount of C3d3 was detected. In the plasma from postsurgical patients in whom activation of the complement system was considered to be in an acute phase, C3d3 was detected, but the C3d2 level was higher than the C3d3 level. In the plasma from patients with systemic lupus erythematosus having the normal C3d level, C3d3 was a major fragment. It is predicted that the preponderant presence of C3d3 in plasma could be the result of chronic continuous complement activation by immune complexes.

T lymphocytes bearing the Fc receptors for IgG (E+ F c gamma + or TG cells) in 38 patients with B-cell chronic lymphocytic leukaemia (B-CLL) were quantified by a simple one-step double-rosette technique. This assay detects the TG lymphocytes from total peripheral blood mononuclear cells (MNC) on the basis of their capacity to bind simultaneously sheep red cells and chicken erythrocytes sensitized with anti-CRBC rabbit IgG. The data obtained were comparable to those evaluated by the more elaborate conventional two-step method, which requires initial T-cell purification. The double-rosette technique is specific for T cells and it may be adapted as a routine clinical laboratory assay for TG cells in B-CLL patients who have very low T/B cell ratio owing to clonal expansion of B cells.

This article describes a modified immunofluorescent antibody technique for the detection of a glomerular fixed tubular nephritogenic antigen in the rat. The presence of the nephritogenic antigen in the glomeruli of rats can be detected by this modified technique, while the conventional method gives negative results.

Two immunoperoxidase staining systems based on the avidin-biotin interaction were compared, using monoclonal antibodies and conventional antisera in cryostat and paraffin sections, respectively. Efficiencies were compared with respect to the highest titer of primary antibody that could be used to detect antigen. The labeled avidin-biotin (LAB) method (primary antibody-biotinylated secondary antibody-avidin-horseradish peroxidase conjugate) was found to be more efficient than the avidin-biotin complex (ABC) kit method (primary antibody-biotinylated secondary antibody-ABC "complex") by factors of 4-8 with respect to the detection of lymphocyte surface antigens in cryostat sections and the detection of immunoglobulins, prostate-specific antigen, and keratin in paraffin sections.

There has been some controversy regarding the relative merits of cell lines versus frozen tissue substrates for the detection of antinuclear antibodies (ANA) by indirect immunofluorescence. We have compared two cell lines (KB and HEP2) with frozen mouse kidney for the detection of ANA in several groups of individuals. Cell lines were more likely to detect ANA than frozen mouse kidney in normal individuals and in hospital and clinic patients with diseases other than connective tissue diseases when sera were examined at manufacturer's recommended screening dilutions. There was also a trend for the cell lines to demonstrate ANA more frequently than mouse kidney in patients with systemic lupus erythematosus and other connective tissue diseases, but the differences were not statistically significant. Centromere antibodies could be reliably suspected only on cell lines and could be confirmed only if mitotic figures were present.

We evaluated the clinical usefulness of lipid-bound sialic acid (LSA) as a "tumor marker" and assessed individual and carcinoembryonic antigen (CEA) in cancer patients. Serum LSA and CEA concentrations were measured by the resorcinol method after total lipid extraction and isolation of the sialolipid fraction, and by Abbott enzyme immunoassay procedures, respectively. Results indicate that the frequency of elevation and mean LSA values were highest in patients with lung cancer (318 mg/liter), intermediate in miscellaneous (210 mg/liter) and colorectal cancers (200 mg/liter), and lowest in breast cancer (175 mg/liter); while mean CEA values were highest in colorectal cancer (162.5 micrograms/liter), followed by lung (33.8 micrograms/liter), miscellaneous (30.3 micrograms/liter), and breast cancers (11.6 micrograms/liter). Statistically, LSA and CEA values for cancer patients were significantly (P less than 0.001) higher than for normal subjects. The combined measurement of LSA and CEA in serum provides better detection potential for cancer patients than either of the two markers alone.

Serum samples were drawn from 14 healthy volunteers after an overnight fast and again after a meal. Each sample was divided into two aliquots. One aliquot was centrifuged at 20,000 rpm for 20 min, and a portion from the middle of the tube was removed by puncturing the tube's side. All samples were then added to cuvettes containing 0.14 M NaCl alone or 1, 2, 3, or 4% polyethylene glycol in 0.15 M KCl. The light scattering of each tube was measured. The centrifuged samples scattered 58% less light than the uncentrifuged controls. The range of values obtained with the centrifuged samples was also smaller as reflected in the standard deviation of the means obtained at each polyethylene glycol concentration. The coefficient of variation for replicate samples ranged from 0 to 16.6% (mean 5.8%), even when samples were processed differently. Storage at -70 degrees C significantly increased light scattering compared to baseline values. Serum samples were drawn from 44 patients with diseases that have been associated with immune complexes. Nephelometry selectively identified some groups of patients as abnormal. We conclude that preparative ultracentrifugation removes much of the background light scattering of serum samples, including that due to lipid, under conditions that do not sediment out immune complexes. Because it measures a physical property of immune complexes, this assay may provide information that is not available from biological receptor-based assays.