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J Rauch

Publications and source records attributed to J Rauch.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Is there a chronic appendicitis in childhood? Analysis of pediatric surgical patients from 1993-1997].

The right lower quadrant abdominal pain and the "chronic" appendicitis in childhood and adolescence are frequently connected with a lot of different diagnostical problems for the treating physician. Since the introduction of diagnostical laparoscopy and laparoscopical appendectomy in our hospital the rate of appendectomy has been increased to 35% in case of the histological diagnosis of "chronic" appendicitis. A special problem in childhood and adolescence is the request of the parents for clarification of chronic recurrent pain in their children and therefore the demand of laparoscopy and not seldom appendectomy. After appendectomy with the pathological-histological findings of "chronic" appendicitis children are in 83% without any abdominal pain. Therefore the question arises whether there exists a "chronic" appendicitis in childhood justifying surgery in these cases. Although the rate of complications and conversions (3.8%) in diagnostical laparoscopy and laparoscopical appendectomy is quite low the indication should only be made after careful examination considering differential diagnostical problems. In our hospital 56.5% of the children with the histological diagnosis of "chronic" appendicitis suffered retrospectively on other diseases, that had been caused the symptoms of appendicitis. Before operation the patients should be informed on the complications in detail.

Adolescent↗
PubMed1998

Immunological and molecular analysis of three monoclonal lupus anticoagulant antibodies from a patient with systemic lupus erythematosus.

Antiphospholipid antibodies (APA), including lupus anticoagulants (LAC; as detected by in vitro blood clotting tests) and anti-cardiolipin antibodies (ACA; as assayed by solid-phase immunoassay), are strongly associated with recurrent thrombosis, thrombocytopenia, and recurrent fetal loss in some patients with systemic lupus erythematosus (SLE). The combined presence of APA and these clinical manifestations is termed antiphospholipid syndrome (APS). LAC and ACA comprise heterogeneous and somewhat overlapping autoantibody subsets. To date, it is unclear what degree of heterogeneity is present in an individual patient and between patients. To begin to address these issues, we generated three monoclonal LAC antibodies from a patient with SLE and APS. These antibodies were studied for their binding specificities and variable (V) region nucleotide sequences. All three LAC were unreactive with DNA, cardiolipin or other phospholipids. Sequence analysis of these antibodies revealed extensive overlap in their Ig V genes with anti-DNA antibodies and other autoantibodies characteristic of lupus. These data provide the first V gene sequence information on a group of SLE-derived LAC without ACA activity, representative of a similar subset of LAC found in patients with APS.

Adult↗
PubMed1998

Induction of anti-phospholipid autoantibodies by beta2-glycoprotein I bound to apoptotic thymocytes.

The target of many anti-phospholipid autoantibodies (aPL) has been shown to be a complex between anionic phospholipid and the plasma protein beta2-glycoprotein I (beta2GPI) or the protein beta2GPI alone. As aPL binding studies have been performed almost exclusively in vitrothe identity of the natural target and/or immunogen for aPL in vivo remains undetermined. The anionic phospholipids of cell membranes represent an important potential target and immunogen for aPL. Although anionic phospholipids are normally absent from the extracellular surface of cell membranes, they redistribute from the inner to the outer leaflet during apoptosis. We have previously shown that beta2GPI binds selectively to the surface of apoptotic, but not viable, cells, and that binding of beta2GPI to the surface of apoptotic cells generates an epitope recognized by aPL from patients with primary aPL syndrome and systemic lupus erythematosus. We show here that immunization of non-autoimmune mice with beta2GPI combined with, or bound to, apoptotic cells induces aPL and lupus anticoagulant activity. Generation of aPL required heterologous beta2GPI, and occurred upon immunization with apoptotic cells and beta2GPI by three different routes of administration. Importantly, for intravenous immuniz-ations, generation of aPL occurred only when apoptotic cells and beta2GPI were injected together, but not when either was injected alone, suggesting that cell-bound beta2GPI is the true immunogen for production of aPL. Unlike other models of induced aPL, adjuvant was not an absolute requirement. Induced aPL reacted with murine, as well as bovine, beta2GPI, suggesting that heterologous beta2GPI bound to apoptotic cells can break tolerance and induce auto-antibodies reactive with autologous beta2GPI. Combined with our previous data, these results show that apoptotic cells can serve as both immunogens and natural targets for aPL.

Animals↗
PubMed1998

Fast-FISH detection and semi-automated image analysis of numerical chromosome aberrations in hematological malignancies.

A new fluorescence in situ hybridization (FISH) technique called Fast-FISH in combination with semi-automated image analysis was applied to detect numerical aberrations of chromosomes 8 and 12 in interphase nuclei of peripheral blood lymphocytes and bone marrow cells from patients with acute myelogenous leukemia (AML) and chronic lymphocytic leukemia (CLL). Commercially available alpha-satellite DNA probes specific for the centromere regions of chromosome 8 and chromosome 12, respectively, were used. After application of the Fast-FISH protocol, and microscopic images of the fluorescence-labelled cell nuclei were recorded by the true color CCD camera Kappa CF 15 MC and evaluated quantitatively by computer analysis on a PC. These results were compared to results obtained from the same type of specimens using the same analysis system but with a standard FISH protocol. In addition, automated spot counting after both FISH techniques was compared to visual spot counting after standard FISH. A total number of about 3,000 cell nuclei was evaluated. For quantitative brightness parameters, a good correlation between standard FISH labelling and Fast-FISH was found. Automated spot counting after Fast-FISH coincided within a few percent to automated and visual spot counting after standard FISH. The examples shown indicate the reliability and reproducibility of Fast-FISH and its potential for automatized interphase cell diagnostics of numerical chromosome aberrations. Since the Fast-FISH technique requires a hybridization time as low as 1/20 of established standard FISH techniques, omitting most of the time consuming working steps in the protocol, it may contribute considerably to clinical diagnostics. This may especially be interesting in cases where an accurate result is required within a few hours.

Aneuploidy↗
PubMed1998

Lupus anticoagulant antibodies: recognition of phospholipid-binding protein complexes.

Lupus anticoagulant antibodies form a heterogeneous group of antiphospholipid antibodies with rather poorly defined antigens. The role that phospholipid-binding proteins play in lupus anticoagulant antibody activity is a subject of current investigation. Several candidate proteins have been proposed, including beta2-glycoprotein I (beta2GPI), prothrombin, and annexin V. As beta2GPI-dependent lupus anticoagulants will be reviewed elsewhere in this issue, this paper will focus on the involvement of prothrombin and annexin V in lupus anticoagulant activity. Evidence for a role for these proteins in the reactivity and induction of lupus anticoagulant antibodies will be discussed, as well as an apparent requirement for both phospholipid and phospholipid-binding protein. The data presented here suggest that some lupus anticoagulant antibodies recognize and may be induced by complexes of phospholipid and phospholipid-binding proteins, in particular, phospholipid and prothrombin or annexin V.

Animals↗
PubMed1998

Inhibition of lupus anticoagulant activity by hexagonal phase phosphatidylethanolamine in the presence of prothrombin.

We have previously demonstrated that lupus anticoagulant antibodies from patients with systemic lupus erythematosus (SLE) specifically recognize hexagonal (II) phase phosphatidylethanolamine (PE), but not bilayer PE (Thromb Haemost 1989; 62: 892). In those studies, the involvement of proteins in this recognition was not evaluated. To address this issue, we have isolated IgG lupus anticoagulant antibodies from the plasma of SLE patients and evaluated the inhibition of lupus anticoagulant activity by hexagonal (II) phase PE in the presence and absence of purified plasma proteins. All six of the IgG lupus anticoagulant antibodies tested were inhibited by hexagonal (II) phase PE in the presence, but not the absence, of human prothrombin. In contrast, little or no inhibition was observed with prothrombin alone or with PE in combination with either beta2-glycoprotein I or annexin V. These data indicate that, for certain lupus anticoagulant antibodies, inhibition by hexagonal (II) phase PE is dependent on prothrombin, suggesting that these antibodies recognize a complex of PE and prothrombin.

Adult↗
PubMed1997

Catastrophic haemorrhage in a case of paediatric primary antiphospholipid syndrome and factor II deficiency.

The first case of primary antiphospholipid syndrome associated with recurrent life-threatening haemorrhages, due to the coexistence of acquired prothrombin deficiency, is described. Attention is drawn to the difficulty in diagnosing this situation, and therapeutic options are reviewed. Evidence is presented that implicates prothrombin as the protein cofactor for this lupus anticoagulant.

Adolescent↗
PubMed1997

Streptokinase entrapment in interdigitation-fusion liposomes improves thrombolysis in an experimental rabbit model.

The successful design of new thrombolytic agents depends on providing these agents with increased clot selectivity. As recently demonstrated (10), entrapment of tissue plasminogen activator into liposomes apparently provided the selective targeting needed to improve the efficacy of this fibrinolytic agent. To test whether liposomal entrapment would benefit streptokinase, a fibrinolytic agent with a different mode of action and inactivation, we compared liposomal streptokinase with free streptokinase in an experimental rabbit model of thrombolysis. First we adapted a new method to produce liposomes of high entrapment efficiency, termed interdigitation-fusion (IF) liposomes, for the encapsulation of streptokinase. This system was then tested in an in vivo rabbit model of thrombolysis where animals with established clots were infused with either free streptokinase (40,000 U/kg), liposomally entrapped streptokinase, free streptokinase+empty liposomes, or the corresponding amount of empty liposomes or saline. Significant differences (p < 0.05) in the percent clot lysis were observed between saline control (22.4 +/- 3.3%; mean +/- S.E.), free streptokinase (36.3 +/- 3.4%), and liposomal streptokinase (47.4 +/- 1.4%). Importantly, animals treated with empty liposomes experienced a level of thrombolysis (32.4 +/- 2.8%) not different to that produced by free streptokinase or empty liposomes plus free streptokinase (38.0 +/- 2.0%). We believe the effect of liposomes alone is due to a transient redistribution or margination of circulating platelets. When tested in rabbits immunized against streptokinase, liposomal (33.8 +/- 1.5%) but not free streptokinase (29.3 +/- 2.1%) showed significant thrombolytic activity compared to saline (22.4 +/- 3.3%) (p < 0.05). The thrombolytic activity was comparable to free streptokinase in non-immunized rabbits. This suggests liposomal streptokinase would have better thrombolytic activity than streptokinase alone and still provide to those patients possessing high levels of anti-streptokinase antibodies (5% of the population) the equivalent degree of therapy expected from free streptokinase.

Animals↗
PubMed1996

Antineutrophil cytoplasmic autoantibodies interact with primary granule constituents on the surface of apoptotic neutrophils in the absence of neutrophil priming.

The pathogenic role of antineutrophil cytoplasmic autoantibodies (ANCA) remains controversial because of the difficulty in explaining how extracellular ANCA can interact with intracellular primary granule constituents. It has been postulated that cytokine priming of neutrophils (PMN), as may occur during a prodromal infection, is an important trigger for mobilization of granules to the cell surface, where they may interact with ANCA. We show by electron microscopy that apoptosis of unprimed PMN is also associated with the translocation of cytoplasmic granules to the cell surface and alignment just beneath an intact cell membrane. Immunofluorescent microscopy and FACS analysis demonstrate reactivity of ANCA-positive sera and antimyeloperoxidase antibodies with apoptotic PMN, but not with viable PMN. Moreover, we show that apoptotic PMN may be divided into two subsets, based on the presence or absence of granular translocation, and that surface immunogold labeling of myeloperoxidase occurs only in the subset of PMN showing translocation. These results provide a novel mechanism that is independent of priming, by which ANCA may gain access to PMN granule components during ANCA-associated vasculitis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1996

Anti-phospholipid autoantibodies bind to apoptotic, but not viable, thymocytes in a beta 2-glycoprotein I-dependent manner.

Anti-phospholipid autoantibodies (aPL) are associated with a clinical syndrome of hypercoagulability, thrombocytopenia, and fetal loss. Several groups have shown that the in vitro target of many aPL is not a pure phospholipid Ag, but is either a complex between anionic phospholipid and the plasma protein beta2-glycoprotein I (beta 2GPI) or the protein beta 2GPI alone. Anionic phospholipids are normally absent from the extracellular surface of cell membranes but redistribute from the inner to the outer leaflet during apoptosis. We show that aPL bind specifically to apoptotic, but not viable, thymocytes, and that binding is dependent upon the presence of beta 2GPI. Moreover, we show that beta 2GPI binds selectively to the surface of apoptotic thymocytes to generate an epitope for antiphospholipid autoantibodies. These findings suggest that apoptotic cells may be the natural immunogen and/or target for aPL. Moreover, we propose that the interaction of circulating beta 2GPI with redistributed anionic phospholipid may itself generate a novel ligand by which apoptotic cells are recognized directly for phagocytic clearance.

Adsorption↗
PubMed1996

Antibodies against phospholipids other than cardiolipin: potential roles for both phospholipid and protein.

Autoantibodies to phospholipids other than cardiolipin have received less attention, to date, than anti-cardiolipin antibodies. This review focuses on these antibodies and potential roles for both phospholipid and protein in their reactivity. We review data in the literature indicating that antibodies to phosphatidylethanolamine and some lupus anticoagulant antibodies recognize phospholipid-binding proteins in association with phospholipid. Kininogens appear to be involved in the binding of antibodies to phosphatidylethanolamine, while phosphatidylserine-binding proteins, such as prothrombin and annexin V, have been implicated in lupus anticoagulant antibody recognition. These proteins bind to phospholipids that normally reside in the inner monolayer of the cell membrane, suggesting that exposure of these lipids is necessary for protein binding and antibody recognition to occur. In contrast, other autoantibodies, in particular those reactive with erythrocytes, appear to be directed at phospholipids that normally occur in the outer membrane leaflet, such as phosphatidylcholine. In summary, there is clearly accumulating evidence that antibodies to phospholipids other than cardiolipin recognize epitopes on phospholipid-binding proteins. It is not clear whether recognition of these epitopes is due to an increase in antigen density or a change in the protein or phospholipid structure, but it is likely that both protein and phospholipid structure play an important role in the in vivo interactions of these antibodies.

Annexin A5↗
PubMed1996

Cytoreductive surgery in the management of metastatic renal cell carcinoma: the UCLA experience.

We assessed the role of cytoreductive surgery in patients with metastatic renal cell carcinoma (RCC) selected for interleukin-2 (IL-2)-based immunotherapy. Sixty-three consecutive newly diagnosed patients with metastatic RCC were treated at our institution between April, 1990 and October, 1994. The patients were selected based on their ability to undergo a radical nephrectomy and to receive a combination of interleukin-2 and interferon alfa (IFN-alpha). The mean age was 58.7 years (range, 34-74 years). All but one patient had an Eastern Cooperative Oncology Group performance status of 0 or 1, and presented with metastatic disease and locally advanced primary tumors. All patients successfully underwent cytoreductive nephrectomy, but 6 patients (10%) required concomitant resection of caval thrombus, 3 (5%) required partial hepatectomy, 2 (3%) needed duodenal repairs, and 1 (2%) required a splenectomy. Postoperative complications were observed in 8 patients (12.7%). There were no postoperative mortalities. Seven patients (11%) could not undergo immunotherapy because of myocardial infarctions (n = 2), no growth of tumor infiltrating lymphocytes (TILs) (n = 1), deterioration of performance status (n = 1), transient ischemic attack (n = 1), chronic renal failure (n = 1), and a diagnosis other than RCC (n = 1). Overall, 56 of 63 (88%) patients selected underwent immunotherapy. Among these 56 patients, a response rate of 33.9% [7 (12.5%) complete, and 12 (21.4%) partial] was observed. Moreover, the 2- and 3-year survival rates were 43% and 38%, respectively. Our results support the argument for an aggressive approach (surgery combined with IL-2-based immunotherapy including TILs) in the management of metastatic RCC. Further studies are needed to elucidate the individual contributions of these therapeutic processes.

Adult↗
PubMed1995

Constitutive secretion of transgene-encoded IgG2b autoantibodies leads to symptoms of autoimmune disease.

Anti-DNA Ab are strictly regulated, except in autoimmunity, where they are expressed and may contribute to pathogenicity. To study constitutive anti-DNA Ab secretion in nonautoimmune mice, two anti-dsDNA H/L chain transgene combinations were constructed using an IgG2b C region with secretory but no transmembrane domain exons. One H/L combination, consisting of the VH3H9 H and V kappa 4 L chain transgenes, was chosen to recreate 3H9, an autoantibody that originally arose in an autoimmune MRL/lpr mouse; the other paired a higher affinity variant of VH3H9, 56R, with the same V kappa 4 L chain. Elevated titers of IgG2b along with normal levels of other isotypes were observed in transgene-positive mice, indicating that constitutive transgene-directed Ab secretion was achieved. Sera and hybridoma supernatants from VH3H9 gamma transgene-positive animals exhibited binding to dsDNA, ssDNA, and cardiolipin. Mice expressing the 56R gamma H chain and the V kappa 4 L chain showed enhanced binding. Expression of the transgenes correlated with signs of autoimmune disease, including prolonged plasma clotting in vitro, and reduced litter size. The results suggest that even a single autoreactive H chain that escapes tolerance may suffice to induce features of autoimmune disease.

Animals↗
PubMed1995

p32, a platelet autoantigen recognized by an SLE-derived autoantibody that inhibits platelet aggregation.

We have previously described an SLE-derived human hybridoma autoantibody, 9604, which binds to activated but not to resting platelets, inhibits platelet aggregation, and immunoprecipitates a surface-labelled poly-peptide of 32,000 molecular weight (MW) (p32). In the present study, using a murine monoclonal anti-p32 antibody (8E8), we show that p32 is responsible for the binding of 9604 to activated platelets. First, 8E8 bound to the surface of activated but not resting platelets, as detected by flow cytometry, showing saturation with 1900 antibody molecules bound/platelet and a Kd of 72 nM. Second, complete inhibition of the binding of 9604 to ADP-activated platelets by 8E8 and inhibition of the reactivity of 8E8 with p32 by 9604 demonstrated that 8E8 and 9604 recognize the same 32,000 MW platelet polypeptide. Isolation of platelet proteins, using an 8E8-affinity column, showed high MW bands corresponding to multimers of p32 under non-reducing conditions, and isolated p32 tended to self-associate even under reducing conditions. High performance liquid chromatography (HPLC) demonstrated that the native p32-containing protein has an approximate MW of 450,000. A comparison of the functional properties of murine monoclonal 8E8 and human monoclonal 9604 revealed that both antibodies are cytotoxic to platelets in 51Cr-release assays. In contrast, 8E8, unlike 9604, did not affect platelet aggregation, suggesting that different epitopes may be recognized by the two antibodies. These findings demonstrate that p32 is a subunit of an activation marker that is expressed on the surface of activated platelets and recognized by an SLE-derived anti-platelet autoantibody. Our data also indicate that murine monoclonal antibodies produced against platelet autoantigens may not mimic the functional activities of spontaneously occurring autoantibodies, probably due to the recognition of different epitopes.

Animals↗
PubMed1995

Anti-DNA and anti-platelet specificities of SLE-derived autoantibodies: evidence for CDR2H mutations and CDR3H motifs.

Although polyreactivity appears to be a characteristic feature of natural autoantibodies, polyreactive anti-DNA autoantibodies can be derived both from patients with autoimmune disease and from normal individuals. It is unclear whether these autoantibodies differ depending on their origin, but previous studies from our laboratory have suggested that polyreactive systemic lupus erythematosus (SLE)-derived platelet-binding anti-DNA autoantibodies have more restricted antigen reactivity and greater functional activity than normal-derived polyreactive autoantibodies. The objective of the present study was to characterize the VH and VL region sequences of 10 human hybridoma anti-DNA autoantibodies derived from peripheral blood lymphocytes of different origins [SLE, rheumatoid arthritis (RA), or normal] to determine whether there are structural differences between these autoantibodies. We show that although some unmutated germline structures (VH and VL) are represented, these are not restricted to anti-DNA autoantibodies from normal individuals and that two normal-derived anti-DNA antibodies showed quite extensively mutated VH genes. However, these mutations, unlike those found in the CDR2H of several of the SLE-derived antibodies, did not appear to be antigen-selected. Three different amino acid motifs, putatively involved in antigen binding specificity, were observed in the CDR3H segments of some of the autoantibodies. One was the previously described YYGSG motif, which was found in a normal-derived anti-DNA autoantibody, while two new potential motifs were observed only in SLE-derived platelet-binding anti-DNA autoantibodies. These data suggest that antigenic and functional differences between SLE-derived and normal-derived platelet-binding anti-DNA autoantibodies may be due to antigen-selected mutations in the CDR2H and specific amino acid motifs in the CDR3H.

Amino Acid Sequence↗
PubMed1995

Inhibition of platelet aggregation by an SLE-derived human hybridoma autoantibody against an activation-dependent antigen.

Anti-platelet autoantibodies may be responsible for hematological complications in patients with systemic lupus erythematosus (SLE), but the mechanisms by which these antibodies cause abnormal hemostasis remain unknown. In the present study, using fluorescence activated cell sorter (FACS) analysis, we demonstrate that an SLE-derived human hybridoma autoantibody, 9604, recognizes a surface antigen expressed on platelets activated by ADP, calcium ionophore A23187, or phorbol myristate acetate (PMA), showing saturation with approximately 2,000 antibody molecules bound per platelet and a Kd of 41 nM. The binding of 9604 to activated platelets was significantly inhibited by EDTA, indicating partial dependence on divalent cations. It did not appear to be dependent on platelet secretion, nor did it directly affect alpha-granule or dense granule secretion. The protein antigen responsible for the binding of 9604 to activated platelets was characterized by Western blot and immunoprecipitation and shown to have a native molecular weight (M. W.) of greater than 400,000, with a 32,000 M. W. subunit (p 32). Antibody 9604 had little or no effect on the shape change and the initial rate of primary aggregation of normal platelets. In contrast, 9604 inhibited secondary aggregation of stirred platelet suspensions (IC50 < or = 1 nM) following activation by ADP, thromboxane A2 mimetic U46619, or calcium ionophore A23187, but not PMA or thrombin. The inhibition of large platelet aggregate formation (secondary aggregation), with a major shift to smaller microaggregates and singlets, was confirmed by direct particle count and sizing studies. The functional inhibition of platelet aggregation by an SLE-derived human hybridoma autoantibody in vitro suggests one potential mechanism that may play a role in the hemostatic disorders found in SLE.

Adenosine Diphosphate↗
PubMed1994

Monospecific but not polyreactive human hybridoma rheumatoid factors exhibit preferential binding specificities for IgG3 and IgG4.

Among 38 human hybridoma-derived monoclonal rheumatoid factors (RFs) generated from patients with either rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE), two groups of RFs can be identified. Monospecific RFs were derived primarily from patients with RA and are characterized by a binding specificity for IgG3 and/or IgG4. Polyreactive RFs were derived largely from patients with SLE and show a broader pattern of reactivity to all four isotypes of IgG. Neither population of RFs was exclusive to either disease. The binding specificities identified appear to be different from the RFs isolated from patients with mixed cryoglobulinemia and may reflect a different antigen selection mechanism.

Adult↗