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Kelkar NS, Goldberg BS, Dufloo J, Bruel T, Schwartz O, Hessell AJ, Ackerman ME. Sex- and species-associated differences in complement-mediated immunity in humans and rhesus macaques. mBio 2024; 15:e0028224. [PMID: 38385704 PMCID: PMC10936177 DOI: 10.1128/mbio.00282-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/23/2024] Open
Abstract
The complement system can be viewed as a "moderator" of innate immunity, "instructor" of humoral immunity, and "regulator" of adaptive immunity. While sex is known to affect humoral and cellular immune systems, its impact on complement in humans and rhesus macaques, a commonly used non-human primate model system, has not been well studied. To address this knowledge gap, we analyzed serum samples from 90 humans and 72 rhesus macaques for the abundance and activity of the complement system components. While sequences of cascade proteins were highly conserved, dramatically different levels were observed between species. Whereas the low levels detected in rhesus samples raised questions about the suitability of the test for use with macaque samples, differences in levels of complement proteins were observed in male and female humans. Levels of total and antibody-dependent deposition of C1q and C3b on a glycosylated antigen differed between humans and rhesus, suggesting differential recognition of glycans and balance between classical and alternative activation pathways. Functional differences in complement-mediated lysis of antibody-sensitized cells were observed in multiple assays and showed that human females frequently exhibited higher lytic activity than human males or rhesus macaques, which typically did not exhibit such sex-associated differences. Other differences between species and sexes were observed in more narrow contexts-for only certain antibodies, antigens, or assays. Collectively, these results expand knowledge of sex-associated differences in the complement system in humans, identifying differences absent from rhesus macaques.IMPORTANCEThe complement system is a critical part of host defense to many bacterial, fungal, and viral infections. In parallel, rich epidemiological, clinical, and biomedical research evidence demonstrates that sex is an important biological variable in immunity, and many sex-specific differences in immune system are intimately tied with disease outcomes. This study focuses on the intersection of these two factors to define the impact of sex on complement pathway components and activities. This work expands our knowledge of sex-associated differences in the complement system in humans and also identifies the differences that appear to be absent in rhesus macaques, a popular non-human primate model. Whereas differences between species suggest potential limitations in the ability of macaque model to recapitulate human biology, knowledge of sex-based differences in humans has the potential to inform clinical research and practice.
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Affiliation(s)
- Natasha S. Kelkar
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire, USA
| | | | - Jérémy Dufloo
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, Paris, France
| | - Timothée Bruel
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, Paris, France
- Vaccine Research Institute, Créteil, France
| | - Olivier Schwartz
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, Paris, France
- Vaccine Research Institute, Créteil, France
| | - Ann J. Hessell
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Margaret E. Ackerman
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire, USA
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, USA
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Kelkar NS, Goldberg BS, Dufloo J, Bruel T, Schwartz O, Hessell AJ, Ackerman ME. Sex and species associated differences in Complement-mediated immunity in Humans and Rhesus macaques. bioRxiv 2023:2023.10.23.563614. [PMID: 37961263 PMCID: PMC10634758 DOI: 10.1101/2023.10.23.563614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The complement system can be viewed as a 'moderator' of innate immunity, 'instructor' of humoral immunity, and 'regulator' of adaptive immunity. While sex and aging are known to affect humoral and cellular immune systems, their impact on the complement pathway in humans and rhesus macaques, a commonly used non-human primate model system, have not been well-studied. To address this knowledge gap, we analyzed serum samples from 90 humans and 75 rhesus macaques for the abundance and activity of the complement system components. While sequences of cascade proteins were highly conserved, dramatically different levels were observed between species. Whereas the low levels detected in rhesus samples raised questions about the suitability of the test, differences in levels of complement proteins were observed in male and female humans. Levels of total and antibody-dependent deposition of C1q and C3b on a glycosylated antigen differed between human and rhesus, suggesting differential recognition of glycans. Functional differences in complement-mediated lysis of antibody-sensitized cells were observed in multiple assays and showed that human females frequently exhibited higher lytic activity than human males or rhesus macaques, which typically did not exhibit such sexual dimorphism. Other differences between species and sexes were observed in more narrow contexts-for only certain antibodies, antigens, or assays. Collectively, these results expand our knowledge of sexual dimorphism in the complement system in humans, identifying differences that appear to be absent from rhesus macaques.
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Affiliation(s)
- Natasha S. Kelkar
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH, USA
| | - Benjamin S. Goldberg
- Thayer School of Engineering, Dartmouth College, Hanover, NH, USA
- Present Address: Metaphore Biotechnologies Inc., Cambridge, MA, USA
| | - Jérémy Dufloo
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015 Paris, France
- Present Address: Institute for Integrative Systems Biology (I2SysBio), Universitat da Valencia-CSIC, 46980 Valencia, Spain
| | - Timothée Bruel
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015 Paris, France
- Vaccine Research Institute, 9400 Créteil, France
| | - Olivier Schwartz
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015 Paris, France
- Vaccine Research Institute, 9400 Créteil, France
| | - Ann J. Hessell
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Margaret E. Ackerman
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH, USA
- Thayer School of Engineering, Dartmouth College, Hanover, NH, USA
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Goldberg BS, Spencer DA, Pandey S, Ordonez T, Barnette P, Yu Y, Gao L, Dufloo J, Bruel T, Schwartz O, Ackerman ME, Hessell AJ. Complement contributes to antibody-mediated protection against repeated SHIV challenge. Proc Natl Acad Sci U S A 2023; 120:e2221247120. [PMID: 37155897 PMCID: PMC10193994 DOI: 10.1073/pnas.2221247120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/10/2023] [Indexed: 05/10/2023] Open
Abstract
The first clinical efficacy trials of a broadly neutralizing antibody (bNAb) resulted in less benefit than expected and suggested that improvements are needed to prevent HIV infection. While considerable effort has focused on optimizing neutralization breadth and potency, it remains unclear whether augmenting the effector functions elicited by broadly neutralizing antibodies (bNAbs) may also improve their clinical potential. Among these effector functions, complement-mediated activities, which can culminate in the lysis of virions or infected cells, have been the least well studied. Here, functionally modified variants of the second-generation bNAb 10-1074 with ablated and enhanced complement activation profiles were used to examine the role of complement-associated effector functions. When administered prophylactically against simian-HIV challenge in rhesus macaques, more bNAb was required to prevent plasma viremia when complement activity was eliminated. Conversely, less bNAb was required to protect animals from plasma viremia when complement activity was enhanced. These results suggest that complement-mediated effector functions contribute to in vivo antiviral activity, and that their engineering may contribute to the further improvements in the efficacy of antibody-mediated prevention strategies.
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Affiliation(s)
| | - David A. Spencer
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR97006
| | - Shilpi Pandey
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR97006
| | - Tracy Ordonez
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR97006
| | - Philip Barnette
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR97006
| | - Yun Yu
- Biostatistics Shared Resources, Knight Cancer Institute, Oregon Health and Science University, Portland, OR97239
- Biostatistics & Bioinformatics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR97006
| | - Lina Gao
- Biostatistics Shared Resources, Knight Cancer Institute, Oregon Health and Science University, Portland, OR97239
- Biostatistics & Bioinformatics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR97006
| | - Jérémy Dufloo
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015Paris, France
- Université de Paris, École doctorale BioSPC 562, 75013Paris, France
| | - Timothée Bruel
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015Paris, France
- Vaccine Research Institute, 94000Créteil, France
| | - Olivier Schwartz
- Institut Pasteur, Université de Paris, CNRS UMR3569, Virus and Immunity Unit, 75015Paris, France
- Vaccine Research Institute, 94000Créteil, France
| | - Margaret E. Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, NH03755
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth College, Hanover, NH03755
| | - Ann J. Hessell
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR97006
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Rosenberg YJ, Ordonez T, Khanwalkar US, Barnette P, Pandey S, Backes IM, Otero CE, Goldberg BS, Crowley AR, Leib DA, Shapiro MB, Jiang X, Urban LA, Lees J, Hessell AJ, Permar S, Haigwood NL, Ackerman ME. Evidence for the Role of a Second Fc-Binding Receptor in Placental IgG Transfer in Nonhuman Primates. mBio 2023; 14:e0034123. [PMID: 36946726 PMCID: PMC10127586 DOI: 10.1128/mbio.00341-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 02/21/2023] [Indexed: 03/23/2023] Open
Abstract
Transplacental transfer of maternal antibodies provides the fetus and newborn with passive protection against infectious diseases. While the role of the highly conserved neonatal Fc receptor (FcRn) in transfer of IgG in mammals is undisputed, recent reports have suggested that a second receptor may contribute to transport in humans. We report poor transfer efficiency of plant-expressed recombinant HIV-specific antibodies, including engineered variants with high FcRn affinity, following subcutaneous infusion into rhesus macaques close to parturition. Unexpectedly, unlike those derived from mammalian tissue culture, plant-derived antibodies were essentially unable to cross macaque placentas. This defect was associated with poor Fcγ receptor binding and altered Fc glycans and was not recapitulated in mice. These results suggest that maternal-fetal transfer of IgG across the three-layer primate placenta may require a second receptor and suggest a means of providing maternal antibody treatments during pregnancy while avoiding fetal harm. IMPORTANCE This study compared the ability of several human HIV envelope-directed monoclonal antibodies produced in plants with the same antibodies produced in mammalian cells for their ability to cross monkey and mouse placentas. We found that the two types of antibodies have comparable transfer efficiencies in mice, but they are differentially transferred across macaque placentas, consistent with a two-receptor IgG transport model in primates. Importantly, plant-produced monoclonal antibodies have excellent binding characteristics for human FcRn receptors, permitting desirable pharmacokinetics in humans. The lack of efficient transfer across the primate placenta suggests that therapeutic plant-based antibody treatments against autoimmune diseases and cancer could be provided to the mother while avoiding transfer and preventing harm to the fetus.
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Affiliation(s)
| | - Tracy Ordonez
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | | | - Philip Barnette
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Shilpi Pandey
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Iara M. Backes
- Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Claire E. Otero
- Department of Pediatrics, Weill Cornell Medicine, New York, New York, USA
| | | | - Andrew R. Crowley
- Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - David A. Leib
- Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
| | - Mariya B. Shapiro
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | | | | | | | - Ann J. Hessell
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Sallie Permar
- Department of Pediatrics, Weill Cornell Medicine, New York, New York, USA
| | - Nancy L. Haigwood
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Margaret E. Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, USA
- Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire, USA
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Spencer DA, Goldberg BS, Pandey S, Ordonez T, Dufloo J, Barnette P, Sutton WF, Henderson H, Agnor R, Gao L, Bruel T, Schwartz O, Haigwood NL, Ackerman ME, Hessell AJ. Phagocytosis by an HIV antibody is associated with reduced viremia irrespective of enhanced complement lysis. Nat Commun 2022; 13:662. [PMID: 35115533 PMCID: PMC8814042 DOI: 10.1038/s41467-022-28250-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 01/12/2022] [Indexed: 12/19/2022] Open
Abstract
Increasingly, antibodies are being used to treat and prevent viral infections. In the context of HIV, efficacy is primarily attributed to dose-dependent neutralization potency and to a lesser extent Fc-mediated effector functions. It remains unclear whether augmenting effector functions of broadly neutralizing antibodies (bNAbs) may improve their clinical potential. Here, we use bNAb 10E8v4 targeting the membrane external proximal region (MPER) to examine the role of antibody-mediated effector and complement (C’) activity when administered prophylactically against SHIV challenge in rhesus macaques. With sub-protective dosing, we find a 78–88% reduction in post-acute viremia that is associated with 10E8v4-mediated phagocytosis acting at the time of challenge. Neither plasma nor tissue viremic outcomes in vivo is improved with an Fc-modified variant of 10E8v4 enhanced for C’ functions as determined in vitro. These results suggest that effector functions inherent to unmodified 10E8v4 contribute to efficacy against SHIVSF162P3 in the absence of plasma neutralizing titers, while C’ functions are dispensable in this setting, informing design of bNAb modifications for improving protective efficacy. While antibodies neutralize HIV via Fab recognition of viral surface antigens, antibody Fc domains mediate effector functions, including antibody-dependent cellular phagocytosis (ADCP) and cytotoxicity (ADCC), and complement (C') activity. Here, Spencer et al. modify bNAb 10E8v4 to enhance C'-mediated potency in SHIV challenged rhesus macaques to probe its function in protection, showing that in the absence of neutralization, enhancing C' activities in vitro adds no value toward reducing viremia in either blood or tissue.
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Affiliation(s)
- David A Spencer
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA.,Absci Corp, 1810 SE Mill Plain Blvd., Vancouver, WA, 98683, USA
| | | | - Shilpi Pandey
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Tracy Ordonez
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Jérémy Dufloo
- Virus & Immunity Unit, Department of Virology, Institut Pasteur, Paris, France.,Institute for Integrative Systems Biology, University of Valencia-CSIC, Calle Catedràtic Agustín Escardino Benlloch 9, 46980, Paterna, Valencia, Spain
| | - Philip Barnette
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - William F Sutton
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Heidi Henderson
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Rebecca Agnor
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR, USA
| | - Lina Gao
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR, USA
| | - Timothée Bruel
- Virus & Immunity Unit, Department of Virology, Institut Pasteur, Paris, France.,Vaccine Research Institute, Creteil, France
| | - Olivier Schwartz
- Virus & Immunity Unit, Department of Virology, Institut Pasteur, Paris, France.,Vaccine Research Institute, Creteil, France
| | - Nancy L Haigwood
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA.,Department of Molecular Microbiology & Immunology, School of Medicine, Oregon Health & Science University, Portland, OR, USA
| | | | - Ann J Hessell
- Division of Pathobiology & Immunology, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA.
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Goldberg BS, Ackerman ME. Antibody-mediated complement activation in pathology and protection. Immunol Cell Biol 2020; 98:305-317. [PMID: 32142167 DOI: 10.1111/imcb.12324] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 02/27/2020] [Accepted: 03/03/2020] [Indexed: 01/10/2023]
Abstract
Antibody-dependent complement activity is associated not only with autoimmune morbidity, but also with antitumor efficacy. In infectious disease, both recombinant monoclonal antibodies and polyclonal antibodies generated in natural adaptive responses can mediate complement activity to protective, therapeutic or disease-enhancing effect. Recent advances have contributed to the structural resolution of molecular complexes involved in antibody-mediated complement activation, defining the avid nature of participating interactions and pointing to how antibody isotype, subclass, hinge flexibility, glycosylation state, amino acid sequence and the contextual nature of the cognate antigen/epitope are all factors that can determine complement activity through impact on antibody multimerization and subsequent recruitment of complement component 1q. Beyond the efficiency of activation, complement activation products interact with various cell types that mediate immune adherence, trafficking, immune education and innate functions. Similarly, depending on the anatomical location and extent of activation, complement can support homeostatic restoration or be leveraged by pathogens or neoplasms to enhance infection or promote tumorigenic microenvironments, respectively. Advances in means to suppress complement activation by intravenous immunoglobulin (IVIG), IVIG mimetics and complement-intervening antibodies represent proven and promising exploratory therapeutic strategies, while antibody engineering has likewise offered frameworks to enhance, eliminate or isolate complement activation to interrogate in vivo mechanisms of action. Such strategies promise to support the optimization of antibody-based drugs that are able to tackle emerging and difficult-to-treat diseases by improving our understanding of the synergistic and antagonistic relationships between antibody mechanisms mediated by Fc receptors, direct binding and the products of complement activation.
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Affiliation(s)
| | - Margaret E Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, NH, USA.,Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
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Goldberg BS, Sottilare RA, Brawner KW, Holden HK. Predicting Learner Engagement during Well-Defined and Ill-Defined Computer-Based Intercultural Interactions. Affective Computing and Intelligent Interaction 2011. [DOI: 10.1007/978-3-642-24600-5_57] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Goldberg BS, Shah BA, Wysoki MG, Simmons M, Koenigsberg RA, Squires F, Faro S, Tsai FY. Lumbar agenesis with sacral sparing: a case report. J Neuroimaging 1999; 9:184-7. [PMID: 10436763 DOI: 10.1111/jon199993184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Caudal agenesis or caudal regression syndrome refers to a spectrum of malformations involving the lower spine, which can result in significant progressive or permanent neurologic defects. Caudal agenesis is frequently associated with other congenital anomalies of the axillary skeleton, hindgut and genitourinary systems. Described in this paper is a patient who presented with multiple clinical and radiographic findings consistent with caudal agenesis. This case is unique in that there is total absence of the lumbar vertebral column with an intact spinal cord and bony sacrum.
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Affiliation(s)
- B S Goldberg
- Department Radiologic Sciences, MCP Hahnemann University, Philadelphia, PA 19129, USA
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Abstract
Novel porous sheets containing commercially available cellulosic ion exchange media of several different functionalities in a PVC matrix have been prepared and evaluated. The advantages of these materials are resistance to alkali, clean in place procedures and low nonspecific binding. These sheets thus provide well-known and well-characterized particulate chromatographic media in a porous sheet format. The porous sheet format permits use of short, squat geometries (stacked sheets) as well as tolerance of high pressure gradients. The net result is the ability to handle much higher flow rates (10-fold or greater) than achievable by comparable cellulosic packed columns of the neat particulate media. Chromatographic separation of natural egg white proteins by a linear salt gradient on a single sheet of 1.3-mm thickness was demonstrated. In addition, a very significant advantage of the porous sheet format is that it permits the fabrication of devices which are not possible with particulate media. An example of such a device is the Acti-Mod Spiral Module. In the spiral module a spiral flow channel is formed by wrapping the porous sheet material around a mandrel. Embossed ribbing in the porous sheet provides channel spacing. The small open channel accommodates high flow rates of biological suspensions while the porous sheet walls selectively remove components of the suspension.
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Marshall FF, Reiner WG, Goldberg BS. The embryologic origin of the caput epididymidis in the rat. Invest Urol 1979; 17:78-82. [PMID: 447490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The ACI rat with its known incidence of ipsilateral agenesis of the kidney and ductus deferens provides an excellent mammalian model for the study of the embryologic origin or the caput epididymidis. Because a portion of the caput epididymidis remains in these affected animals, it seems to be derived from the mesonephric tubules rather than the mesonephric duct in the rat. Histochemical assays also support the common origin of both the ductuli efferentes and caput epididymidis from the mesonephric tubules.
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Goldberg BS, Weston WL, Kohler PF, Harris MB, Humbert JR. Transcutaneous leukocyte migration in vivo: cellular kinetics, platelet and C5a dependent activity. J Invest Dermatol 1979; 72:248-52. [PMID: 379238 DOI: 10.1111/1523-1747.ep12531707] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A simple quantitative method for the measurement of leukotaxis in vivo is described. Duplicate skin chambers are placed over tape-stripped skin with 50% autologous serum--50% Hank's balanced salt solution as the attractant. Neutrophils predominate throughout 24 hr in this method with no change to mononuclear cells. A recommended modification of our original method is that chambers are sampled and removed after 8 hr rather than 24 hr since the majority of leukocyte migration occurs within the first 8 hr. Analysis of serum factors showed that heat-inactivation of the serum (56degreesC for 30 min) had no effect. However, depleting platelets or C5 from the serum removed approximately 90% of chemotactic activity for human neutrophils in vivo. Platelets, presumably through activity of their granules, enzymatically cleaves C5a from C5 in plasma. We conclude that C5a, after cleavage from C5, accounts for the majority of chemattractant activity in vivo.
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12
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Goldberg BS. Part-time evening dental hygiene program. J Am Dent Hyg Assoc 1974; 48:99-100. [PMID: 4525633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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