Immune complexes in transitional cell carcinoma

Electrophoretic, chromatographic and immunological studies of human urinary proteins

Urinary proteins from both sexes were analyzed by high resolution two-dimensional gel electrophoresis (2-DE). For well reproducible 2-DE patterns, the samples were concentrated and desalted in one step by vacuum dialysis. A reference map for urine proteins was established by the analysis of urine from 10 healthy persons. Proteins in urine that share immunogenicity with serum proteins were identified by use of antibody to whole human-serum protein in an affinity-column fractionation of urine and differential analysis of the adsorbed (serum component) and unadsorbed (non-serum component) fractions. For identification of individual proteins, coelectrophoresis, immunoblotting and affinity chromatography with corresponding antibodies were used. Proteins identified in the map, besides known serum proteins, included: the subunit of Tamm-Horsefall protein, the secretory component of IgA, constant breakdown products of alpha 1-antitrypsin and retinol-binding protein, the five isoforms of the beta chain of human chorionic gonadotropin and the subunit of prostatic acid phosphatase. In addition, we could demonstrate three proteins which are markedly pronounced in female urine, especially pregnant women. To get more information about the native properties of various urinary proteins, they were separated into four main peaks according to their sizes using fast protein liquid chromatography equipment. Possible interpolypeptide disulfide bonds were studied using a nonreducing 2-DE system. 2-DE in combination with other methods seems to be a valuable tool for the characterization of urinary proteins in defined renal or extra-renal diseases. An example is given by analyzing the immune complexes from seven patients with a urinary tract infection.

HIV-associated immune-mediated renal disease

Although focal glomerulosclerosis is the most common renal disease, other proliferative glomerulonephritides are encountered in HIV-infected patients. We studied four HIV-infected patients with renal insufficiency, proteinuria, and proliferative glomerulonephritis, consistent with immune-mediated disease, to investigate the role of the virus and immune complexes in the pathogenesis of the nephropathy. Circulating immune complexes (CICs) and HIV-reactive antibodies were measured and characterized in each patient. Renal biopsy tissue was acid eluted, and the eluate analyzed. DNA extracted from biopsies was subjected to the polymerase chain reaction (PCR) to detect HIV genome. CICs were detected in each patient: an IgA-p24 HIV antigen complex and an IgG antibody-gp 120 HIV antigen complex in two patients; two patients had an IgG-p24 HIV antigen complex. Identical complexes were eluted from renal tissue in the first three patients; p24 HIV antigen, and complement from the fourth. The eluted antibodies reacted with the HIV antigens from the isolated CICs. Direct immunofluorescence for viral antigen in the eluted glomerular tissue revealed HIV antigens; PCR confirmed the presence of gag genome in all four biopsies. We conclude both circulating and in-situ HIV antigen-specific immune complexes may be associated with glomerulonephritis in HIV infected patients. Viral incorporation into renal tissue may be important in the pathogenesis of HIV-associated renal disease.

Analysis of circulating immune complexes isolated from plasma, cerebrospinal fluid and urine

The protein nature of soluble immune complexes (IC) from fresh plasma, cerebrospinal fluid (CSF), and urine was studied by combining several analytical and biochemical techniques. In plasma and CSF, free immunoglobulins G were separated from larger IC by gel filtration with a fast protein liquid chromatographic system. In urine, IC were separated by precipitation with polyethylene glycol. IC were further purified by protein-A and protein-G affinity chromatography and analyzed by two-dimensional gel electrophoresis. Apart from plasma samples from healthy donors, IC from cases with macrocreatine kinase type 1 and multiple sclerosis were analyzed. For CSF two cases of multiple sclerosis and for urine one case with urinary tract infection are shown. The method can be used for the examination of IC of unknown protein composition in body fluids.

Effects of sperm-reactive antibodies present in human infertile sera on fertility of female rabbits

Sera (n = 19) from immunoinfertile patients were analyzed for cross-reaction with lithium diiodosalicylate (LIS)-solubilized human sperm extract (HSE), protamine and fertilization antigen (FA-1) using an enzyme-linked immunosorbent assay (ELISA). Among the sera tested, 63% reacted with HSE, 58% with protamine and 63% with FA-1. None of the sera from male or female infertile patients was found to contain immune complexes, indicating the antibodies were present in free form. The seven sera that reacted strongest with HSE inhibited human sperm function in sperm penetration of zona-free hamster ova and were associated with fertilization failure in human in vitro fertilization (IVF) technique. The six of these sera that showed binding to rabbit sperm, especially in the head region, also inhibited fertility in female rabbits. Antibodies reactive with FA-1 and not those reactive with protamine reduced fertility in female rabbits. These results indicate that mammalian sperm have several fertilization-related antigens that are evolutionarily conserved. These data also indicate that the rabbit can provide an animal model for studying antibody-mediated human infertility.

Immune complex assays: diagnostic and clinical application

The presence of circulating immune complexes have been described in many different human disease states but the significance of their presence has always been a subject for debate. Improvements in the methods of detecting immune complexes have demonstrated a wide degree of heterogeneity, which accounts for the difficulty in obtaining accurate and reproducible measurements, even in the same individual. Techniques for isolating individual complexes, characterizing their pathophysiological properties, and biochemically analyzing the nature of the complexed antigen are now being used to provide data that is helping to clarify the role of immune complexes in the pathogenesis of disease. In addition, such studies are also providing data which is proving that immune complexes have a potential role in immune regulation.

Circulating immune complexes and immunosuppressive acidic protein in patients with renal cell carcinoma

Sera from 23 patients with renal cell carcinoma were tested for circulating immune complexes by Clq binding assay and immunosuppressive acidic protein by single radial immunodiffusion. The mean values of circulating immune complexes and immunosuppressive acidic protein in the patients were significantly higher than those of normal controls, and over-all positive rates were 52 and 35 per cent, respectively. There was a significant correlation between immunosuppressive acidic protein levels and the extent of tumor invasion. Immunosuppressive acidic protein may be a more useful marker than circulating immune complexes. However, presently synthetic evaluations of patients with various nonspecific markers, including these 2 factors, will be necessary.

Immune complexes in urine and serum of patients with bladder cancer

The urine and/or serum of 43 patients with bladder cancer was tested for the presence of immune complexes. Immune complexes were present more frequently in the urine (38 per cent) than in the serum (23 per cent). Urinary immune complexes were elevated in 10 per cent of the patients with no tumor (group 1), 25 per cent with superficial neoplasms (group 2) and 89 per cent with infiltrating or metastatic disease (group 3), which compared favorably to elevated serum immune complexes in 20, 25 and 33 per cent of the patients, respectively. The incidence of urinary immune complexes was statistically significant when compared in patients with and without active tumors (p less than 0.03), and when group 3 patients were compared to those in group 1 or 2 (p less than 0.01 and p less than 0.03, respectively). Unlike serum immune complexes urinary immune complexes appeared to correlate with the presence and stage of bladder cancer.