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Nester C, Nast C, Appel G, Barratt J, Fervenza F, Fremeaux-Bacchi V, Remuzzi G, Rovin B, Wong E, Bourne E, Marinucci L, Grayson D, Patel R, Sheridan W. POS-045 Evaluating BCX9930, an Oral Factor D Inhibitor for Treatment of Complement-Mediated Kidney Disease: A Proof-of-Concept Study (RENEW). Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.04.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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2
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Barratt J, Rovin B, Zhang H, Kashihara N, Maes B, Rizk D, Trimarchi H, Sprangers B, Meier M, Kollins D, Wang W, Magirr A, Perkovic V. POS-546 EFFICACY AND SAFETY OF IPTACOPAN IN IgA NEPHROPATHY: RESULTS OF A RANDOMIZED DOUBLE-BLIND PLACEBO-CONTROLLED PHASE 2 STUDY AT 6 MONTHS. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.01.577] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Rovin B, Furie R, Aroca G, Garg J, Alvarez A, Fragoso-Loyo H, Zuta Santillan E, Brunetta P, Schindler T, Looney C, Hassan I, Cascino M, Malvar A. SUN-374 B-CELL DEPLETION AND RESPONSE IN A RANDOMIZED, CONTROLLED TRIAL OF OBINUTUZUMAB FOR PROLIFERATIVE LUPUS NEPHRITIS. Kidney Int Rep 2020. [DOI: 10.1016/j.ekir.2020.02.913] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Schindler T, Rovin B, Furie R, Leandro M, Clark M, Brunetta P, Garg J. AB0423 Nobility, A Phase 2 Trial To Assess The Safety and Efficacy of Obinutuzumab, A Novel Type 2 Anti-CD20 Monoclonal Antibody (MAB), in Patients (PTS) with ISN/RPS Class III or IV Lupus Nephritis (LN). Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.2397] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tamirou F, Lauwerys B, Dall'Era M, Mackay M, Rovin B, Cervera R, Houssiau F. OP0265 A 24-Hour Proteinuria Cutoff Level of 0.7 Gram After 12 Months of Treatment Best Predicts Long-Term Renal Outcome in Lupus Nephritis: Data from the Maintain Nephritis Trial:. Ann Rheum Dis 2015. [DOI: 10.1136/annrheumdis-2015-eular.3278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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van Vollenhoven R, Aranow C, Rovin B, Wagner C, Zhou B, Gordon R, Hsu B. OP0047 A Phase 2, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Proof-Of-Concept Study to Evaluate the Efficacy and Safety of Sirukumab in Patients with Active Lupus Nephritis. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.3974] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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7
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Mok CC, Birmingham D, Ho LY, Hebert L, Rovin B. THU0302 Hepcidin, Interleukin-6 and Anemia of Chronic Inflammation in Systemic Lupus Erythematosus (SLE). Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Satoskar AA, Brodsky SV, Nadasdy G, Bott C, Rovin B, Hebert L, Nadasdy T. Discrepancies in glomerular and tubulointerstitial/vascular immune complex IgG subclasses in lupus nephritis. Lupus 2011; 20:1396-1403. [DOI: 10.1177/0961203311416533] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Background and objectives: Lupus nephritis is characterized by glomerular and extraglomerular immune complex deposition in the kidney. It is unclear whether the same circulating immune complexes deposit in the glomeruli and in extraglomerular structures, or whether they are pathogenetically different. Differences in the IgG subclass composition may point towards different pathways in the formation of glomerular and extraglomerular immune complexes. Therefore we investigated IgG subclass distribution in the immune complex deposits at these anatomic sites.Design: A total of 84 biopsies diagnosed as lupus nephritis and classified according to the International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification, were examined by direct immunofluorescence staining for IgG subclasses. The IgG subclass composition in the glomerular, tubular basement membrane (TBM) and vascular wall deposits was compared. We also correlated the presence/absence of interstitial inflammation and IgG subclasses in the TBM and vascular deposits. Lastly, we looked for correlation between staining for IgG subclasses and complement C1q and C3 staining.Results: IgG staining was present in the TBM in 52/84 biopsies, and in the vascular walls in 40/84 biopsies. IgG subclass distribution was discrepant between glomerular and TBM deposits in 36/52 biopsies, and between glomerular and vascular deposits in 27/40 biopsies. Interstitial inflammation did not correlate with the presence of IgG staining or distribution of IgG subclasses in the TBM. Interstitial inflammation was more common in biopsies of African–American patients than Caucasian patients. The IgG subclass staining correlated with C1q staining in all the three compartments.Conclusions: The antibody composition of the glomerular and extraglomerular immune complex deposits appear to differ from each other. They may not represent the same preformed immune complexes from the circulation. It is likely that their pathogenesis and site of formation are different.
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Affiliation(s)
- AA Satoskar
- The Ohio State University Medical Center, 1Department of Pathology
| | - SV Brodsky
- The Ohio State University Medical Center, 1Department of Pathology
| | - G Nadasdy
- The Ohio State University Medical Center, 1Department of Pathology
| | - C Bott
- The Ohio State University Medical Center, 1Department of Pathology
| | - B Rovin
- Department of Internal Medicine, Division of Nephrology, Columbus, OH, USA
| | - L Hebert
- Department of Internal Medicine, Division of Nephrology, Columbus, OH, USA
| | - T Nadasdy
- The Ohio State University Medical Center, 1Department of Pathology
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Blum KA, Ruppert AS, Woyach JA, Jones JA, Andritsos L, Flynn JM, Rovin B, Villalona-Calero M, Ji J, Phelps M, Johnson AJ, Grever MR, Byrd JC. Risk factors for tumor lysis syndrome in patients with chronic lymphocytic leukemia treated with the cyclin-dependent kinase inhibitor, flavopiridol. Leukemia 2011; 25:1444-51. [PMID: 21606960 PMCID: PMC3162125 DOI: 10.1038/leu.2011.109] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Tumor lysis syndrome (TLS) has been described in over 40% of patients with chronic lymphocytic leukemia treated with the cyclin-dependent kinase inhibitor, flavopiridol. We conducted a retrospective analysis to determine predictive factors for TLS. In 116 patients, the incidence of TLS was 46% (95% CI: 36-55%). In univariable analysis, female gender, greater number of prior therapies, Rai stages III-IV, adenopathy ≥ 10 cm, splenomegaly, del(11q), decreased albumin and increased absolute lymphocyte count, white blood cell count (WBC), β2-microglobulin, and lactate dehydrogenase were associated (P < 0.05) with TLS. In multivariable analysis, female gender, adenopathy ≥ 10 cm, elevated WBC, increased β2-microglobulin, and decreased albumin were associated with TLS (P < 0.05). With respect to patient outcomes, 49 and 44% of patients with and without TLS, respectively, responded to flavopiridol (P = 0.71). In a multivariable analysis, controlling for number of prior therapies, cytogenetics, Rai stage, age and gender, progression-free survival (PFS) was inferior in patients with TLS (P = 0.01). Female patients and patients with elevated β2-microglobulin, increased WBC, adenopathy ≥ 10 cm and decreased albumin were at highest risk and should be monitored for TLS with flavopiridol. TLS does not appear to be predictive of response or improved PFS in patients receiving flavopiridol.
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Affiliation(s)
- K A Blum
- Division of Hematology, Department of Internal Medicine, The Arthur G James Comprehensive Cancer Center and The Ohio State University, Columbus, OH 43210, USA.
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Mamtani M, Rovin B, Brey R, Camargo JF, Kulkarni H, Herrera M, Correa P, Holliday S, Anaya JM, Ahuja SK. CCL3L1 gene-containing segmental duplications and polymorphisms in CCR5 affect risk of systemic lupus erythaematosus. Ann Rheum Dis 2007; 67:1076-83. [PMID: 17971457 DOI: 10.1136/ard.2007.078048] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVES There is an enrichment of immune response genes that are subject to copy number variations (CNVs). However, there is limited understanding of their impact on susceptibility to human diseases. CC chemokine ligand 3 like-1 (CCL3L1) is a potent ligand for the HIV coreceptor, CC chemokine receptor 5 (CCR5), and we have demonstrated previously an association between CCL3L1-gene containing segmental duplications and polymorphisms in CCR5 and HIV/AIDS susceptibility. Here, we determined the association between these genetic variations and risk of developing systemic lupus erythaematosus (SLE), differential recruitment of CD3+ and CD68+ leukocytes to the kidney, clinical severity of SLE reflected by autoantibody titres and the risk of renal complications in SLE. METHODS We genotyped 1084 subjects (469 cases of SLE and 615 matched controls with no autoimmune disease) from three geographically distinct cohorts for variations in CCL3L1 and CCR5. RESULTS Deviation from the average copy number of CCL3L1 found in European populations increased the risk of SLE and modified the SLE-influencing effects of CCR5 haplotypes. The CCR5 human haplogroup (HH)E and CCR5-Delta32-bearing HHG*2 haplotypes were associated with an increased risk of developing SLE. An individual's CCL3L1-CCR5 genotype strongly predicted the overall risk of SLE, high autoantibody titres, and lupus nephritis as well as the differential recruitment of leukocytes in subjects with lupus nephritis. The CCR5 HHE/HHG*2 genotype was associated with the maximal risk of developing SLE. CONCLUSION CCR5 haplotypes HHE and HHG*2 strongly influence the risk of SLE. The copy number of CCL3L1 influences risk of SLE and modifies the SLE-influencing effects associated with CCR5 genotypes. These findings implicate a key role of the CCL3L1-CCR5 axis in the pathogenesis of SLE.
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Affiliation(s)
- M Mamtani
- The Veterans Administration Center for AIDS and HIV-1 Infection, South Texas Veterans Health Care System and Department of Medicine, University of Texas Health Science Center at San Antonio, Texas 78229-7870, USA
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Byrd JC, Lin TS, Dalton JT, Phelps M, Fischer B, Moran M, Blum K, Rovin B, Colevas AD, Grever MR. Pharmacologically derived schedule of flavopiridol has significant efficacy in refractory, genetically high risk chronic lymphocytic leukemia (CLL). J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.6516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6516 Background: Promising pre-clinical activity with flavopiridol in CLL was followed by disappointing clinical trial results. Differential protein binding of flavopiridol in pre-clinical studies may have misdirected the target concentration and administration schedule in CLL trials. Methods: We initiated a phase I study based on pharmacokinetic (PK) modeling showing that 1.5–2.0 μM flavopiridol for 4–6 hours was necessary for anti-CLL activity in vitro with 10% human serum. A 30 minute loading dose followed by a 4 hour infusion every 4 of 6 weeks was pursued. Eligibility included refractory/relapsed CLL, intact organ function, and performance status of ≤ 2. Results: Fifty-six pts have been enrolled ( Table ) with a median of 4 prior therapies, and most fludarabine-refractory. Dose-limiting toxicity in cohort 2 was tumor lysis syndrome (TLS). Cohort 1 was expanded with aggressive TLS prophylaxis. Of 20 pts in cohort 1, 8 (40%) had a partial response (PR) with a median response duration exceeding 12 months. The 0.5 and 4.5 hr Cmax were 2.08 μM and 0.96 μM. PK modeling showed that higher dose in the 4-hr infusion would achieve desired 4.5 hr Cmax. This escalation was done in cohorts 3 and 4 ( Table 1 ) with acceptable toxicity. In cohort 3, 19 pts enrolled with 14 pts being dose escalated. Improved cytoreduction was seen in most pts with dose escalation. Ten (53%) of pts attained a PR. The 0.5 and 4.5 hr Cmax was 1.95 μM and 1.54 μM in cohort 3;dose escalation continues in cohort 4. WBC of ≥ 200 × 109/L was associated with TLS (5 of 8 pts) versus those with WBC < 200 × 109/L (1 of 34 pts). As such, cohort 4 excludes pts with WBC ≥ 200 × 109/L for safety. Currently there are 14 pts in cohort 4 with only 1 case of TLS. Response assessment for cohort 4 is underway; activity appears similar to cohort 3. Conclusions: Flavopiridol with this PK directed schedule has significant clinical activity independent of the presence of del(17p13.1) and is one of the most active agents in clinical trials for CLL. [Table: see text] No significant financial relationships to disclose.
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Affiliation(s)
- J. C. Byrd
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - T. S. Lin
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - J. T. Dalton
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - M. Phelps
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - B. Fischer
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - M. Moran
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - K. Blum
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - B. Rovin
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - A. D. Colevas
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
| | - M. R. Grever
- OSU CLL Team; Ohio State University, Columbus, OH; National Cancer Institute, Bethesda, MD
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Abstract
Among the many functions of trophoblast cells is the production of prostaglandins (PGs) for governing several fetoplacental vascular functions during gestation and the triggering of events leading to parturition. Recent evidence suggests that pro-inflammatory cytokines such as tumour necrosis factors (TNF-alpha) induce PG formation via cyclooxygenase-2 (COX-2), a highly inducible enzyme whose gene is regulated at least in part by inducible transcription factor NF-kappaB. To examine the mechanism by which COX-2-driven PG biosynthesis occurs in trophoblast cells, we utilized the immortalized trophoblast-like cell line ED(27). These cells exhibit many of the properties of villous or extravillous trophoblasts and produce large amounts of PGs in response to TNF-alpha. We demonstrated that challenge of ED(27)cells with TNF-alpha caused binding of the NF-kappaB complex to its kappaB site followed by increased accumulation of COX-2 transcripts. In addition, the inhibitor of NF-kappaB, IkappaB-alpha, became phosphorylated and was rapidly degraded in cytokine-treated cells; this process was abolished by co-incubation with the proteasome inhibitor, MG-132. Finally, when cells were pre-incubated with MG-132 and then challenged with TNF-alpha, PG formation was attenuated in a concentration-dependent manner. These data indicate that, in ED(27)trophoblast-like cells isolated from the first-trimester placenta, TNF-alpha treatment leads to activation of NF-kappaB and subsequent transcription of the COX-2 gene.
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Affiliation(s)
- D A Kniss
- Department of Obstetrics and Gynecology (Division of Maternal-Fetal Medicine and Laboratory of Perinatal Research), The Ohio State University, College of Medicine and Public Health, 1654 Upham Drive, Columbus, OH 43210, USA.
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Schreiner GF, Rovin B, Lefkowith JB. The antiinflammatory effects of essential fatty acid deficiency in experimental glomerulonephritis. The modulation of macrophage migration and eicosanoid metabolism. J Immunol 1989; 143:3192-9. [PMID: 2809195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Dietary polyunsaturated fatty acid modulation exerts a beneficial effect in immune-mediated glomerulonephritis. To elucidate the mechanisms underlying this phenomenon, the effects of essential fatty acid (EFA) deficiency on the heterologous phase of nephrotoxic nephritis in rats (induced by the injection of a rabbit antiglomerular basement membrane antibody) were studied. The heterologous phase of nephrotoxic nephritis was characterized by an invasion of leukocytes into the glomerulus. Polymorphonuclear neutrophils predominated early on (3 h), whereas macrophages predominated at 24 and 72 h. EFA deficiency selectively prevented the influx of macrophages into the glomerulus. The invasion of polymorphonuclear neutrophils, in contrast, was unaffected. The influx of leukocytes into the glomerulus during nephritis was accompanied by a marked enhancement (10- to 40-fold) in glomerular thromboxane and leukotriene B4 production. EFA deficiency largely attenuated this change. Renal dysfunction during the heterologous phase of nephritis was manifested as azotemia, polyuria, sodium retention, and proteinuria. With EFA deficiency, polyuria, azotemia, and sodium retention were not seen. Proteinuria was reduced by approximately 85%. To address whether the lack of macrophage migration into the glomerulus in the context of nephritis with EFA deficiency might be due to a functional defect in macrophage migration, the chemotactic responsiveness of EFA-deficient macrophages was examined. EFA-deficient macrophages displayed normal chemotactic migration toward activated C. In sum, EFA deficiency prevents the invasion of macrophages into the glomerulus in nephrotoxic nephritis and attenuates the accompanying metabolic and functional alterations, but does not affect macrophage chemotactic responsiveness. Alterations in macrophage elicitation and lipid mediator generation by inflamed glomeruli thus appear to be central to the salutary effect of dietary polyunsaturated fatty acid modification on glomerulonephritis.
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Affiliation(s)
- G F Schreiner
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
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Schreiner GF, Rovin B, Lefkowith JB. The antiinflammatory effects of essential fatty acid deficiency in experimental glomerulonephritis. The modulation of macrophage migration and eicosanoid metabolism. The Journal of Immunology 1989. [DOI: 10.4049/jimmunol.143.10.3192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Dietary polyunsaturated fatty acid modulation exerts a beneficial effect in immune-mediated glomerulonephritis. To elucidate the mechanisms underlying this phenomenon, the effects of essential fatty acid (EFA) deficiency on the heterologous phase of nephrotoxic nephritis in rats (induced by the injection of a rabbit antiglomerular basement membrane antibody) were studied. The heterologous phase of nephrotoxic nephritis was characterized by an invasion of leukocytes into the glomerulus. Polymorphonuclear neutrophils predominated early on (3 h), whereas macrophages predominated at 24 and 72 h. EFA deficiency selectively prevented the influx of macrophages into the glomerulus. The invasion of polymorphonuclear neutrophils, in contrast, was unaffected. The influx of leukocytes into the glomerulus during nephritis was accompanied by a marked enhancement (10- to 40-fold) in glomerular thromboxane and leukotriene B4 production. EFA deficiency largely attenuated this change. Renal dysfunction during the heterologous phase of nephritis was manifested as azotemia, polyuria, sodium retention, and proteinuria. With EFA deficiency, polyuria, azotemia, and sodium retention were not seen. Proteinuria was reduced by approximately 85%. To address whether the lack of macrophage migration into the glomerulus in the context of nephritis with EFA deficiency might be due to a functional defect in macrophage migration, the chemotactic responsiveness of EFA-deficient macrophages was examined. EFA-deficient macrophages displayed normal chemotactic migration toward activated C. In sum, EFA deficiency prevents the invasion of macrophages into the glomerulus in nephrotoxic nephritis and attenuates the accompanying metabolic and functional alterations, but does not affect macrophage chemotactic responsiveness. Alterations in macrophage elicitation and lipid mediator generation by inflamed glomeruli thus appear to be central to the salutary effect of dietary polyunsaturated fatty acid modification on glomerulonephritis.
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Affiliation(s)
- G F Schreiner
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - B Rovin
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - J B Lefkowith
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
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Rovin B, Molnar J, Chevalier D, Ng P. Interaction of plasma fibronectin (pFN) with membranous constituents of peritoneal exudate cells and pulmonary macrophages. J Leukoc Biol 1984; 36:601-20. [PMID: 6593391 DOI: 10.1002/jlb.36.5.601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The prominent role of plasma fibronectin (pFN) in the host defense system as an opsonin for gelatin (collagen)-coated colloids has been established. In the present study we investigated the interaction of pFN and membrane isolates from cells devoid of collagen, as well as several tissues. In a liver slice assay system it was shown that subcellular membrane fractions from lung macrophages, peritoneal exudate cells, spleen, tests, and liver were able to competitively inhibit the pFN-mediated uptake of 125I-gelatin coated latex beads (gLtx) at low concentrations. Endocytosis of 125I-labeled membrane isolates by macrophage monolayers was also promoted by addition of pFN. In an attempt to characterize the membrane component(s) interacting with pFN, it was found that mild extraction procedure with 1 M KBr could release a significant amount of this inhibitory activity. Further studies demonstrated that the agent(s) responsible for inhibition of gLtx uptake was heat sensitive, not altered by trypsin treatment, and did not contain actin, a protein known to interact with pFN. This work indicates that pFN interacts specifically with an as yet unknown membrane component(s) and that such interaction will promote clearance of cellular debris by macrophages. This suggests that pFN may be an important opsonin for the reticuloendothelial system in clearance of collagenous and noncollagenous cellular debris once they are exposed to interact with it.
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Telser A, Rovin B. A specific stain for sulfhydryl groups in proteins after separation by polyacrylamide gel electrophoresis. Biochim Biophys Acta 1980; 624:363-71. [PMID: 6158337 DOI: 10.1016/0005-2795(80)90077-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A new method is described for specifically staining protein sulfhydryl groups after the proteins have been separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in slab gels. The stain will detect as little as 0.25 microgram of lysozyme and 1 microgram of most other proteins; the range of sensitivity for a specific protein depending on its sulfhydryl content. Proteins with no cysteine residues (type I collagen) and glycoproteins do not cause spurious staining.
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