Denture stomatitis is the most common form of oral Candida infection in humans. In the current study, the distribution of Candida albicans serotype A and B as well as the activity of the secreted acid proteinase were determined in clinical isolates from patients with denture stomatitis. It was found that 70% of individuals with clinical signs of denture stomatitis exhibited fungal growth, with C.
View Article and Find Full Text PDFSera of healthy humans contain natural cytotoxic IgM antibodies that specifically recognize a Mr 260,000 antigen (NB-p260) on the surface of human neuroblastoma (NB) cells. Here we demonstrate that anti-NB IgM antibodies prepared from different healthy individuals induce, in all human NB cell lines analyzed thus far, typical morphological and biochemical features of apoptosis including nuclear fragmentation, chromatin condensation, and DNA fragmentation. Both the binding of human anti-NB IgM to NB cells and the induction of apoptosis could be inhibited by preincubation of NB cells with murine IgG raised against purified NB-p260.
View Article and Find Full Text PDFNonhuman primates provide valuable animal models for human diseases. However, studies assessing the role of cell-mediated immune responses have been difficult to perform in nonhuman primates. We have shown that CD8+ lymphocyte-mediated immunity in rhesus monkeys can be selectively eliminated using the mouse-human chimeric anti-CD8 monoclonal antibody cM-T807.
View Article and Find Full Text PDFUrticaria is one of the most common and, in its chronic course, excruciating dermato-allergic diseases. Apart from the dermatological diagnosis, the identification and evaluation of causal triggering factors is of utmost importance. Here a 'three-step guideline' (according to Ring and Przybilla) has gained acceptance, ranging a general basic examination via an intensive investigation until oral provocation tests for food allergy and oral provocation tests for idiosyncrasy (OPTI) against food additives.
View Article and Find Full Text PDFIsoforms of aspartyl proteinase (Sap), which are encoded by at least nine related SAP genes, have been implicated to be a major virulence factor of the opportunistic yeast Candida albicans in experimental infections. Although it is generally assumed that proteinases are important for infections, detailed information on the pathogenetic role of Saps is still lacking. The same applies to the question whether the genes and corresponding isoforms of the enzyme are expressed during oral infection.
View Article and Find Full Text PDFCobra venom factor (CVF)-induced consumption of complement proteins was used to investigate the role of complement in vivo in the immunopathogenesis of simian immunodeficiency virus of macaques (SIVmac) infection in rhesus monkeys. Repeated administration of CVF was shown to deplete complement to <5% of baseline hemolytic activity of serum complement for 10 days in a normal monkey. Three groups of SIVmac-infected animals were then evaluated: monkeys treated with CVF resulting in complement depletion from days -1 to 10 postinfection, monkeys treated with CVF resulting in complement depletion from days 10 to 21 postinfection, and control monkeys that received no CVF.
View Article and Find Full Text PDFNormal human sera of healthy adults contain natural IgM antibodies which are cytotoxic for human neuroblastoma cells. In this study, we evaluated the anti-neuroblastoma activity of these natural IgM antibodies in nude rats bearing solid human neuroblastoma tumours. A single intravenous (i.
View Article and Find Full Text PDFHuman neuroblastoma cells contain a 260 kDa surface-associated antigen (NB-p260) that is recognised by natural cytotoxic IgM antibodies. In this study we demonstrate that NB-p260 is expressed in vivo in a neuroblastoma tumour specimen but not in normal human tissues of neuronal origin. Since MYCN amplification is a clinical marker of neuroblastoma disease progression, we analysed the expression of NB-p260 in human neuroblastoma cell lines with different MYCN amplification status.
View Article and Find Full Text PDFJ Mol Med (Berl)
January 1998
Candida sake is routinely identified in the oral cavity of patients infected with the human immunodeficiency virus (HIV) using the commercial identification system ATB 32 C. To establish the prevalence of C. sake and to evaluate this designation repeatedly found using the ATB 32 C system, 94 HIV-infected patients were investigated for the presence of oral candidosis based on clinical and microbiological grounds.
View Article and Find Full Text PDFBackground: Palpable migratory arciform erythema is clinically characterized by sharply circumscribed, infiltrated erythematous patches that tend to spread irregularly, resulting in arciform morphologic features. The histopathologic features are characterized by a patchy inflammatory perivascular and periadnexal T-lymphocytic infiltrate throughout the dermis. The disease runs a chronic course and is rarely described in the literature.
View Article and Find Full Text PDFA novel cytotoxic mechanism against neuroblastoma (NB) cells based on natural immunoglobulin M serum antibodies is described. The occurrence of these antibodies, which are able to induce complement-mediated cytolysis of NB cells, has been investigated in several age groups of healthy persons and in patients with NB. The cytotoxicity of serum samples has been measured in terms of propidium iodide DNA incorporation using a FACScan.
View Article and Find Full Text PDFNeuroblastoma (NB) is the most common extracranial solid neoplasm of infancy and is associated with very poor prognosis in patients with advanced disease. Current therapeutic regimens of advanced NB which combine surgical resection with radiation therapy and/or chemotherapy brought some improvements, but in a significant number of patients, a cure remains elusive. Normal human serum of healthy adults contains natural IgM antibodies that are cytotoxic for human NB cells.
View Article and Find Full Text PDFIn this report, effects of alpha 1-adrenergic stimulation on phosphatidylcholine (PC) hydrolysis and the subsequent generation of water-soluble choline metabolites were investigated after preincubation of isolated cardiac myocytes of adult rats with [methyl-3H]choline. Choline uptake into cardiac myocytes was apparently mediated by a choline carrier which could be inhibited by hemicholinium-3. Analysis of the intracellular choline metabolites was performed by HPLC.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
April 1996
Neuroblastoma (NB) is characterized by the second highest spontaneous regression of any human malignant disorder, a phenomenon that remains to be elucidated. In this study, a survey of 94 normal human adult sera revealed a considerable natural humoral cytotoxicity against human NB cell lines in approximately one-third of the tested sera of both genders. Specific cell killing by these sera was in the range of 40% to 95%.
View Article and Find Full Text PDFJ Mol Med (Berl)
March 1996
Although Candida albicans infections in humans are increasingly frequent, our understanding of the host-parasite relationship is limited. The secreted aspartic proteinase of C. albicans was first described in 1965 and has proved to be a major factor in virulence.
View Article and Find Full Text PDFThe restriction of alternative complement pathway activation in fluid phase or on nonactivator surfaces has been described as the major physiologic function of the complement regulatory protein factor H. In this study, we provide evidence that factor H is also a restriction factor of classical pathway activation on the surface of nucleated cells. We found that C3b was rapidly converted to inactivated C3b (iC3b) on human SK-MEL-93-2 melanoma cells after classical pathway activation with the murine monoclonal IgG3 Ab R24 directed against the disialoganglioside surface Ag GD3.
View Article and Find Full Text PDFThe increased prevalence and the severity of oropharyngeal candidiasis in human immunodeficiency virus (HIV)-positive patients are attributed exclusively to the virus-induced immune deficiency of the host. The present study was aimed at answering the question of whether Candida albicans secretory proteinase, a putative virulence factor of the opportunistic C. albicans yeast, has any potential influence on the clinical manifestation of oropharyngeal candidiasis in HIV-positive patients.
View Article and Find Full Text PDFThirty-two strains of Trichophyton rubrum and 16 strains of Trichophyton mentagrophytes isolated from patients with tinea unguium in various parts of Germany were subjected to a microdilution test with six systemic or topical antimycotic agents. Apart from griseofulvin, there were no species-specific differences between the two species. Terbinafine was the most active antimycotic agent, with a MIC not exceeding 0.
View Article and Find Full Text PDFThe sequential molecular events of the initiation, amplification, and membrane attack phases of classical C pathway activation on nucleated cells were investigated. As a model system, C-susceptible human melanoma cells (SK-MEL-93-2) expressing the disialoganglioside Ag GD3 were studied. Activation of the classical C pathway was initiated by the anti-GD3 mAb R24 (murine IgG3).
View Article and Find Full Text PDFWe established an in vitro adherence model with primarily cultured human keratinocytes as target cells which allows for the investigation of the molecular mechanisms that are responsible for Candida albicans host cell attachment in the initiation of cutaneous candidosis. The extent of C. albicans binding to cultured human keratinocytes was dependent on the yeast inoculum size and the incubation temperature.
View Article and Find Full Text PDFAntimicrob Agents Chemother
October 1993
Toenail tinea is a very recalcitrant dermatosis. Griseofulvin at > or = 500 mg/day is the current medication of choice, but it is minimally successful. In a controlled open trial ultramicrosize griseofulvin (UMSG) at doses of 660 and 990 mg/day was compared with itraconazole at 100 mg/day in 109 patients.
View Article and Find Full Text PDFBackground And Design: Erythema induratum of Bazin, a chronic form of nodular vasculitis, may be associated with chronic infections by Mycobacterium tuberculosis. However, the true origin of the disease is a subject of speculation and remains elusive. Two female patients (58 years old and 33 years old) with a minimum 10-year history of chronic tender ulcerating nodules on the lower aspects of the legs were studied both clinically and in the response of their peripheral T cells to purified protein derivative of tuberculin.
View Article and Find Full Text PDFThe molecular mechanism of complement resistance of the human SK-MEL-170 melanoma cell line was investigated. The cells have been shown to express the C3b-cleaving membrane protease p65. To delineate the molecular consequences of the C3b-cleaving activity for the complement cytotoxicity, the molecular events during the initiation (R24 monoclonal antibody, C1), amplification (C4, C3), and membrane attack (C5, C9) phases of complement were studied in comparison to a complement-susceptible human melanoma line (SK-MEL-93-2).
View Article and Find Full Text PDFHuman melanoma cells resistant to killing by the R24 mAb and human complement rapidly degrade surface-deposited C3b (M. Panneerselvam, S. Welt, L.
View Article and Find Full Text PDFPseudohyphae of Candida albicans bear surface receptors for iC3b and C3d. In order to determine a possible role for these receptors in the pathogenesis of candidiasis, a spontaneous C. albicans mutant, m-10, which exhibits reduced ability to adhere in vitro to fibrin platelet clots and epithelial cells or to cause endocarditis in a rabbit model, and its parent wild-type (wt) strain were compared for receptor expression in rosetting assays with sheep erythrocytes carrying iC3b (EAC1423bi) or C3d (EAC1423d).
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