Search PubMed⌕ Search

Biomedical subjects

K C Hsu

Publications and source records attributed to K C Hsu.

At least 91 records · Page 5Linked to original sources

Natural antibodies in sera from healthy humans to antigens on surfaces of type C RNA viruses and cells from primates.

Sera from healthy humans contained naturally occurring antibody against group- or subgroup-specific antigen on the envelope of the following type C viruses isolated from primates: gibbon ape leukemia virus, simian (woolly monkey) sarcoma virus, baboon endogenous type C virus, and putative human type C viruses [HL23V isolated from blood cells of a patient with acute myelogenous leukemia (HL23) and HEL-12V from human embryonic diploid cells (CIH-32)]. Two sera also reacted with C57BL/6 mouse leukemia induced by Friend virus. These results were obtained by indirect immunoelectron microscopy with various virus-producing cells and by absorption tests using as targets gibbon lymphosarcoma cells that release gibbon ape leukemia virus. In a previous report, the presence of natural antibody in sera from healthy gibbon apes was demonstrated. When the specificities of the human and gibbon natural antibodies were compared, the human natural antibody reacted with two nonproducing culture cell lines of human lymphocytic leukemia (CEM-A and MOLT) and with human embryonic diploid (CIH-1(V-) cells [which became type C virus-producing CIH-32(V+) cells after many passages], but did not react with normal gibbon spleen monolayer cells. In contrast, gibbon natural antibody showed no reaction with CEM-A, MOLT, and CIH-1(V-) cells but reacted with gibbon spleen monolayer cells. Neither human nor gibbon natural antibody that was reactive with gibbon ape leukemia virus crossreacted with feline leukemia virus and mouse wild-type AKR leukemia virus. The gibbon lymphosarcoma cells releasing gibbon ape leukemia virus were used in a screening study of sera from healthy humans. Out of 72 sera screened by indirect immunoelectron microscopy using this system, 55 were positive (76%), i.e., 26 out of 35 males (74%) and 29 out of 37 females (78%). The highest incidence of antibody production was in 1- to 10-year-olds and 31- to 40-year-olds, with the adults exhibiting higher levels. Differences in incidence of natural antibody were not found to be sex-linked. These findings suggest that type C RNA viruses related to the gibbon ape leukemia virus and simian (woolly monkey) sarcoma virus family as well as the baboon endogenous type C virus family may be widespread in humans.

Animals↗

Immunoglobulins, complement and foreign antigens in human tumor cells.

Fluorescein-labeled antibodies (FA) to human immunoglobulins, complement, fetal proteins and other antigens were used to search for these immunologic reactants in malignant and benign neoplasia as well as in control tissues. The FA reacted with five or more target antigens in 42 of 59 (70%) malignant tumors and 21 of 23 (40%) benign tumors. The remaining neoplasia and normal tissues showed positive staining with fewer than five specific antibodies. IgM, IgA, B1C, fetal proteins and HSV were the antigens found most frequently. This indicates that neoplasia exhibits immunologic activity more frequently than normal tissue.

Albumins↗

Interstitial immune complex nephritis in patients with systemic lupus erythematosus.

Interstitial immune complex nephritis in patients with systemic lupus erythematosus (SLE). Renal tissues from 45 patients with SLE nephritis, 34 patients with idiopathic membranous nephropathy (IMN) and 77 patients with minimal glomerular disease (MGD) were studied by light, immunofluorescence and electron microscopy. Interstitial nephritis characterized by focal or diffuse infiltration of inflammatory cells, tubular damage and interstitial fibrosis was observed in 66% of SLE patients. Fluorescein-conjugated antibodies to immunoglobulins or complement or both were bound to peritubular capillaries, interstitium and tubular basement membranes (TBM) in 53% of patients with a granular pattern corresponding to opaque deposits seen by light or electron microscopy or both. Antibodies reactive with thymidine or cytosine or both were bound to interstitial structures in 19% of patients tested and showed the same granular distribution. Interstitial cellular infiltration was rare and deposits of immunoglobulins and complement were rare or absent in IMN and MGD, whereas deposits of DNA products were never observed. The findings are consistent with the interpretation that in patients with SLE nephritis immune deposits, presumably containing DNA-anti-DNA complexes, localize in peritublular capillaries, TBM and interstitum, thereby producing an inflammatory reaction which contributes to development and evolution of renal diseases.

Antibodies↗

Relationship between A-type and C-type particles in cells infected by Rous sarcoma virus.

Chicken cells infected with avian RNA tumor virus often contain small cytoplasmic A-type particles which commonly exist as clusters of 50--100 particles when viewed in thin sections. These particles were found more consistently in Rous sarcoma virus-infected than Rous-associated virus-infected cultures, but were generally present in only a small fraction of the total infected cells. The results of the survey of cells infected with various strains of leukosis-sarcoma viruses led to the hypothesis that the A particles develop in cells undergoing cytopathological degeneration. The hypothesis explains also the evanescent nature of the appearance of these particles in infected cells. The application of immunoelectron microscopic methods using monospecific antisera against viral internal proteins revealed that the A particles contain components immunologically related to the proteins of C-type virus.

Animals↗

Application of immunoperoxidase techniques to localize horseradish peroxidase-tracer in the central nervous system.

Immunoperoxidase techniques are presented which can be used to localize horseradish peroxidase-tracer in paraffin-embedded tissues of the central nervous system. Compared to histochemical methods using frozen sections, these immunologic techniques allow the use of stored, serial paraffin sections, and appear more sensitive for the demonstration of intraneuronal horseradish peroxidase after retrograde transport. The immunoperoxidase bridge techniques from reaction products of high quality which can easily be seen in fine processes.

Animals↗

Association of fibrinogen and microfibrils with trophoblast basement membrane.

Two non-collagenous placental antigens have been detected both in membranes isolated from terminal villi by sieving and sonication and in acetic acid extracts of the villi. One of the antigens is apparently fibrinogen based on immunologic and chemical data. The second, detectable with anti-membrane antiserum after absorption with fibrinogen remained with the fibrinogen-like antigen during isoelectric precipitation at pH 4.7, electrophoresis at pH 8.6 and chromatography on DEAE cellulose. Fractions of villi in which the two antigens occur comprise more than a third of the weight of the villi. The fibrinogen-related antigen was concentrated in placental basement membranes compared to kidney and lung basement membranes. A third antigen common to the membranes, to glomerular basement membrane and to alveolar basement membrane was also detected.

Amino Acids↗

Membranous glomerulopathy in a patient with sarcoidosis.

We describe a case of membranous nephropathy in a patient with pulmonary, splenic and hepatic sarcoidosis. The patient was asymptomatic, and edema was absent notwithstanding the proteinuria (over 8.0 gm/100 ml daily). Prednisone cleared the pulmonary and splenic complications, but the proteinuria, although diminished, persisted. Adjunctive therapy with cyclophosphamide caused further diminishment of the proteinuria. We have reviewed the relationship between the nephropathy and the sarcoidosis and suggest that a causal relationship exists between the two diseases.

Adult↗

Experimental immune complex disease of the lung. The pathogenesis of a laboratory model resembling certain human interstitial lung diseases.

Membranous and/or proliferative pneumonitis, similar in certain features to human interstitial pneumonitis, developed in rabbits making hyperactive antibody response to daily injections of bovine serum albumin (BSA) administered in multiple large doses sufficient to maintain the state of relative antigen-antibody equivalence. The pulmonary lesions were associated with deposition in alveolar capillary walls and interstitium of antigen, host globulin and complement, presumably in immune complexes. In some rabbits chronic interstitial pneumonitis, characterized by thickening of alveolar capillary walls, interstitial fibrosis and deposition of fibrinogen, was observed. The production of immune complex pneumonitis seems to depend on the degree of the antibody response because rabbits developing chronic serum sickness with low doses of BSA, rabbits with acute serum sickness as well as nonresponders showed no pulmonary alterations. This observation is comparable to that described by Dixon in his studies on experimental immune complex glomerulonephritis. It is conceivable that the pulmonary pathology shown here is produced by formation of larger amounts of complexes which may persist longer at critical levels in the circulation than in rabbits immunized with a single daily injection of BSA. In conclusion this study suggests: first, that experimental chronic serum sickness can be used as a model, not only for glomerulonephritis, but also for experimental systemic disease, comparable to human systemic diseases produced by circulating antigen-antibody complexes; and second, that the pathogenesis proposed here offers an alternative to using antilung basement membrane pneumonitis for the experimental approach to the study of human lung immunopathology.

Animals↗

Surface antigens of mammalian sarcoma virus-transformed nonproducer cells.

In vitro, clonal BALB/3T3 mouse cells were transformed into nonproductive sarcoma cells by Kirsten murine sarcoma virus. The resulting cells are called K-BALB. Similarly, the Kirsten sarcoma virus and woolly monkey sarcoma virus transformed normal rat embryonic kidney (NRK) cells to nonproductive sarcoma cells K-NRK and W-NRK, respectively. The presence of sarcoma cell surface antigen (SCSA) on these three different cell lines has been examined by immunoelectron microscopy using the rabbit anti-K-BALB, anti-K-NRK, and anti-W-NRK sera preabsorbed with normal embryonic rat cells, NRK cells, and BALB/3T3 cells. Four different specific sarcoma cell surface antigens have been demonstrated: SCSAa, an antigen specific to the surface of W-NRK cells; SCSAb, a surface antigen common to K-NRK and W-NRK cells; SCSAc, a surface antigen common to K-BALB and W-NRK cells; and SCSAd, a surface antigen broadly reactive with the rabbit antisera to W-NRK, K-NRK, and K-BALB.

Animals↗