RESUMEN
Varicella-zoster virus (VZV) is the etiologic agent of varicella (chickenpox) and herpes zoster (shingles) infections commonly involving skin, mucous membranes, and less frequently the central nervous system. Traditional methods for the laboratory diagnosis of these infections are time-consuming, labor-intensive, and often insensitive. As such, these tests are being replaced by more sensitive and rapid molecular methods. This study evaluated the performance of two different molecular assays, the Simplexa VZV Direct and Simplexa VZV Swab Direct, to detect VZV DNA in cerebrospinal fluid (CSF) and lesion-swab specimens, respectively. The Simplexa VZV Direct and Simplexa VZV Swab Direct assays were compared against individual composite reference methods that varied depending on the sample cohort examined. A total of 883 CSF and 452 cutaneous and mucocutaneous prospective, retrospective, and contrived specimens were evaluated in this multicenter study. The results of this study showed that the Simplexa assays demonstrated near perfect agreement (k = 0.98) compared to the composite reference methods for the detection of VZV in CSF and lesion swab specimens. A further comparison between the standard of care molecular assays employed at the site of specimen collection and the Simplexa assays demonstrated excellent agreement (k = 1.0). The Simplexa assays offer rapid and reliable alternatives for the detection of VZV in certain clinical specimens without the need for nucleic acid extraction.
Asunto(s)
Varicela , Herpes Zóster , Varicela/diagnóstico , Herpes Zóster/diagnóstico , Herpesvirus Humano 3/genética , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Manejo de EspecímenesRESUMEN
A novel, to the best of our knowledge, method of wet chemical etching of sapphire workpieces (such as optics, wafers, windows, and cones), called the sapphire advanced mitigation process (or sapphire AMP), has been developed that exposes sub-surface mechanical damage created during the optical fabrication process and significantly enhances the surface laser damage resistance ($ \gt {2{\times}}$>2×) and mechanical strength (up to $\sim{2.6{\times}}$â¼2.6×). Sapphire AMP involves first treating the workpiece with a mixture of sulfuric and phosphoric acid $([{\rm H_{2}{\rm SO_{4}}}]:[{\rm H_{3}{\rm PO_{4}}}]=1:3)$([H2SO4]:[H3PO4]=1:3) at 220°C, followed with phosphoric acid at 160°C, then with sodium hydroxide base (NaOH) and surfactant at 40°C, and finally with a high-pressure deionized water spray rinse. Sapphire AMP has been demonstrated on both A- and C-plane sapphire workpieces. The mechanism of this etch process involves the reaction of the sapphire $({\rm Al_{2}}{\rm O_{3}})$(Al2O3) surface with sulfuric acid $({\rm H_{2}}{\rm SO_{4}})$(H2SO4) forming aluminum sulfate $[{{\rm Al}_2}{({{\rm SO}_4})_3}]$[Al2(SO4)3], which has low solubility. The high phosphoric acid content in the first and second steps of sapphire AMP results in the efficient conversion of ${{\rm Al}_2}{({{\rm SO}_4})_3}$Al2(SO4)3 to aluminum phosphate $({\rm AlPO_{4}})$(AlPO4), which is very soluble, greatly reducing reaction product redeposition on the workpiece surface. Sapphire AMP is shown to expose sub-surface mechanical damage on the sapphire surface created during the grinding and polishing processes, whose etched morphology has either isotropic or anisotropic evolution depending on the nature of the initial surface damage. Sapphire AMP was also designed to remove the key known surface, laser absorbing precursors (namely, foreign chemical impurities, the fracture surface layer of preexisting sub-surface damage, and reaction product or foreign species redeposition or precipitation). Static and sliding indention induced surface microfractures on sapphire are shown after sapphire AMP to have a significant decrease in the fast photoluminescence intensity (a known metric for measuring the degree of laser damaging absorbing precursors). In addition, the onset of laser damage (at 351 nm 3 ns) on sapphire AMP treated workpieces was shown to increase in fluence from $\sim{4}$â¼4 to $ \gt {9}.{5}\;{{\rm J/cm}^2}$>9.5J/cm2. Finally, biaxial ball-on-ring mechanical tests on sapphire disks showed an increase in the failure stress from 340 MPa (with pre-existing 28 µm flaws) to $\sim{900}\;{\rm MPa}$â¼900MPa after sapphire AMP, which is attributed to the blunting of the surface microfractures.
RESUMEN
Intimate partner violence (IPV) is a public health problem. The purpose of this study was to compare the effectiveness of the HELPP (Health, Education on Safety, and Legal Support and Resources in IPV Participant Preferred) intervention among IPV survivors. A sequential, transformative mixed-methods design was used. Participants were randomly assigned to one of three study groups: Online (ONL), Face-to-Face (FTF), and Waitlist Control (WLC). The HELPP intervention was offered to 32 adult female participants who were 45.2% Asian, 32.3% White, and 22.5% Black. Outcome measures were anxiety, depression, anger, personal, and social support. In total, 64% (n = 20) of the participants reported having experienced IPV before the age of 18. The anger mean score pre-test to post-test difference was significant for ONL (p < 0.001) and WLC (p = 0.01). The personal and social support pre-test to post-test mean score differences were significant for ONL (p < 0.001; p < 0.001) and WLC (p = 0.01; p = 0.006), respectively. The HELPP intervention (1) decreased anxiety, depression, anger, and (2) increased personal and social support in the ONL group. The HELPP information and intervention was shown to be feasible, acceptable, and effective among IPV survivors compared with participants in the WLC group. The WLC participants displayed (1) increased levels of anxiety, depression, and anger and (2) decreased levels of personal and social support, post-intervention. Further research could be conducted to determine if e-mail alone or e-mail plus mobile devices are more useful modes of delivering interventions.
Asunto(s)
Intervención en la Crisis (Psiquiatría) , Servicios de Salud Mental , Sistemas en Línea , Apoyo Social , Maltrato Conyugal/psicología , Telemedicina , Adulto , Ansiedad/etiología , Ansiedad/prevención & control , Depresión/etiología , Depresión/prevención & control , Emociones , Femenino , Humanos , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Proyectos Piloto , Adulto JovenRESUMEN
Resting human CD4 T cells are highly resistant to transfection or infection with lentiviral vectors derived from the human immunodeficiency virus. We now describe a flexible and efficient approach involving virus-like particles containing simian immunodeficiency virus lentiviral gene product protein X and pseudotyping with CXCR4-tropic HIV Env. This method permits effective genetic manipulation of these cells while preserving their naturally quiescent state. This technology can also be extended to primary lymphoid cultures where authentic cellular composition and functional relationships are preserved.
Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Técnicas de Transferencia de Gen , Terapia Genética , Proteínas Virales/genética , Animales , Linfocitos T CD4-Positivos/patología , Vectores Genéticos , VIH-1/genética , Humanos , Lentivirus/genética , Receptores CXCR4/genética , Receptores CXCR4/uso terapéutico , Virus de la Inmunodeficiencia de los Simios , Proteínas Virales/administración & dosificación , Proteínas Virales/uso terapéutico , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/uso terapéuticoRESUMEN
BACKGROUND: Interprofessional communication is essential for the coordination and collaboration of healthcare team members during patient care, especially in critical situations. Therefore, nursing students must learn and practice interprofessional communication skills throughout their education and clinical training. Previous studies evaluating standardized communication frameworks in the United States (e.g., ISBARR [identify, situation, background, assessment, recommendation, and repeat]) suggest that nursing students feel more confident about interprofessional communication and collaboration through familiarity with these frameworks. OBJECTIVE: To evaluate the effect of an ISBARR workshop on knowledge of and attitude about effective communication among Chinese undergraduate students. DESIGN: A pre- and posttest quasi-experimental study. PARTICIPANTS: A convenience sample of 90 undergraduate nursing students at a vocational health college in China. METHOD: The two-part ISBARR workshop featured a lecture and a video-simulation exercise. Differences in students' knowledge of and attitudes about interprofessional communication skills using ISBARR were compared pre- and post-workshop. RESULTS: We observed a statistically significant (p < 0.001) improvement in overall mean scores of students' knowledge of and attitudes about utilizing ISBARR post-workshop. We also observed a statistically significant (p < 0.001) improvement in the overall mean scores of students' knowledge of and attitudes about ISBARR after the video-simulation exercise. CONCLUSION: The ISBARR workshop improved Chinese nursing students' knowledge and attitudes about interprofessional communication. Incorporating ISBARR into the nursing healthcare team eventually can lead to improved patient safety. Subsequent studies should target nursing faculty and clinical instructors to evaluate their knowledge and attitudes about teaching ISBARR and interprofessional education. Improving these attitudes can help establish a positive interprofessional communication learning environment for nursing students in China and other cultural contexts worldwide.
Asunto(s)
Bachillerato en Enfermería , Estudiantes de Enfermería , Actitud , Actitud del Personal de Salud , Comunicación , Humanos , Relaciones Interprofesionales , Grupo de Atención al PacienteRESUMEN
PURPOSE: The following review is offered as an aid for encouraging deeper understanding by pharmacy graduates of approaches to debt management. SUMMARY: The phenomenon of growing debt for pharmacists and other professionals has been well described. Significant debt is widespread with both pharmacy students and graduates; a recent study described the debt-to-income ratio for pharmacists to have risen by 141% between 2010 and 2016. This increasing debt burden causes significant pressure for these individuals-whether while in training, early in their career, or, increasingly, even in midcareer. Dealing with debt has become a major consideration in the profession. Given that financial education is addressed only minimally, if at all, in pharmacy curricula, pharmacists find it challenging to understand and fully consider the myriad factors influencing the accumulation and repayment of debt in the context of their financial goals. Personal financial, repayment, behavioral, and emotional/psychological factors must be considered to choose an optimal strategy to address debt. This article describes various repayment plans, particularly focusing on those offered with direct loans, and it reviews in some detail 5 comprehensive repayment strategies (using these plans). Three case studies derived from real-life pharmacist-planner interactions illustrate the many factors that must be considered as a pharmacist chooses the optimal approach to debt repayment in their unique life situation. CONCLUSION: Education of students and pharmacists regarding the various factors related to handling student debt may facilitate decision-making that is both financially and personally beneficial.
Asunto(s)
Curriculum , Apoyo a la Formación Profesional , HumanosRESUMEN
The high-affinity IL-2-R complex is composed of at least two distinct IL-2-binding subunits, including p55 (Tac, IL-2-R alpha) and p70 (IL-2-R beta). Using a radiolabeled mAb specific for the p55 receptor subunit and cells expressing a homogeneous population of high-affinity binding sites, we demonstrate that p55 is co-internalized with p70 after IL-2 binding to the receptor complex. Endocytosis of p55 depends upon the presence of IL-2 in a form capable of effectively interacting with the p70 subunit. Whether IL-2 is required for high-affinity receptor assembly or triggering of the internalization of preassembled receptors remains unresolved. Together, these findings support the existence of a stable, high-affinity human IL-2-R membrane complex composed of at least the p55 and p70 receptor subunits and IL-2.
Asunto(s)
Endocitosis , Receptores de Interleucina-2/fisiología , Linfocitos T/fisiología , Sitios de Unión , Línea Celular , Humanos , Interleucina-2/metabolismo , Sustancias Macromoleculares , Peso Molecular , Receptores de Interleucina-2/ultraestructuraRESUMEN
High-affinity IL-2-R correspond to a membrane receptor complex composed of two different IL-2-binding proteins, the Tac antigen (alpha chain) and a 70-75 kD beta chain. Using cell lines that express either the alpha or the beta protein, we demonstrate that IL-2 internalization occurs when ligand is bound to the isolated beta chain, but not when it is bound to the isolated alpha chain. The kinetics of IL-2 internalization mediated by the intermediate-affinity beta chain were nearly identical to those of the high-affinity alpha/beta heterodimer (t1/2 of 10-15 min), and each type of receptor targeted the bound IL-2 for intracellular degradation in lysosomes. The beta chain thus appeared to provide the essential element necessary for ligand internalization by both types of IL-2-R.
Asunto(s)
Antígenos de Superficie/metabolismo , Interleucina-2/metabolismo , Receptores Inmunológicos/metabolismo , Animales , Endocitosis , Humanos , Hylobates , Cinética , Unión Proteica , Receptores de Interleucina-2 , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis TumoralRESUMEN
In this report, we have investigated the kinetics of IL-2 binding to the alpha (p55) and beta (p70) IL-2 binding proteins and compared these properties with ligand binding to the high-affinity IL-2-R. The association and dissociation of IL-2 to the alpha (p55) chain occurred with very rapid kinetics (t 1/2 = 4-10 s). In contrast, IL-2 association to, and dissociation from the beta (p70) chain occurred at a greatly reduced rate (t 1/2 = 40-50 min and 200-400 min, respectively). Measurements of IL-2 binding to the high-affinity receptor revealed an interesting composite of these binding properties with a rapid association rate (t 1/2 = 30-45 s) resembling the alpha (p55) chain and a slow dissociation rate (t 1/2 = 270-300 min) similar to the beta (p70) chain. These findings provide additional support for the model of the high-affinity IL-2-R as a heterodimeric membrane complex composed of both the alpha (p55) and beta (p70) subunits and suggest that high-affinity IL-2 binding may involve a conformational change in structure of either or possibly both of the receptor chains. These results highlight the important and perhaps different role played by each subunit in the formation of functional high-affinity IL-2-R.
Asunto(s)
Interleucina-2/farmacocinética , Receptores Inmunológicos/metabolismo , Sitios de Unión , Línea Celular , Humanos , Cinética , Sustancias Macromoleculares , Receptores de Interleucina-2RESUMEN
Radiolabeled molecules from detergent-solubilized human T cell blasts were fractionated on affinity supports coupled with T cell growth factor (TCGF) and anti-Tac antibody. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that a glycoprotein of approximately 58,000 mol wt was bound in both cases. Sequential binding to the two affinity supports demonstrated that the molecules recognized in each instance were identical. Thus, the Tac antigen contains the cellular binding site for TCGF. Note added in proof: Preliminary binding experiments using high concentrations of [3H]leucine, lysine TCGF with a low specific radioactivity indicate the existence of a sizeable pool of receptor sites with an affinity 2,000-10,000 times lower than that of the high affinity receptors measured in Fig. 1. Such sites may explain the numerical discrepancy between early TCGF binding experiments (5) and the binding of the anti-Tac antibody. The hypothesis that the anti-Tac antibody apparently reacts with both classes of receptor would explain its effect on the physiological response (high affinity binding) and the high level of Tac antigen on the cell surface.
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Antígenos de Superficie/inmunología , Receptores Inmunológicos/análisis , Anticuerpos Monoclonales/fisiología , Antígenos de Diferenciación de Linfocitos T , Antígenos de Superficie/análisis , Unión Competitiva , Electroforesis en Gel de Poliacrilamida , Humanos , Interleucina-2/fisiología , Activación de Linfocitos , Receptores de Interleucina-2 , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
T cell activation by antigen/MHC induces the expression of several genes critical to the immune response, including interleukin-2. T cells from mice deficient for the NF-kappa B family member c-rel cannot activate IL-2 gene expression. However, mutating the NF-kappa B site in the IL-2 promoter has only moderate effects. To investigate additional ways c-Rel could regulate IL-2 gene expression, we determined whether c-rel overexpression could increase the activity of other transcription factors involved in IL-2 promoter regulation: NF-AT, Oct/OAP (ARRE-1), and AP-1. In Jurkat TAg cells, overexpression of c-Rel increased AP-1 activation approximately 17-fold. Moreover, AP-1 activity stimulated by anti-TCR Abs or PMA/ionomycin was further increased by c-Rel overexpression. c-Rel overexpression did not affect NF-AT or ARRE-1 activity. Additionally, overexpression of c-Rel activated the nonconsensus AP-1 site from the IL-2 promoter (NF-IL-2B), although to a lesser extent, approximately sixfold. AP-1 activation required both the DNA binding and transactivation domains of c-Rel. Our results may provide an explanation for the effect on IL-2 gene activation in c-rel-deficient mice.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Interleucina-2/biosíntesis , Proteínas Nucleares , Proteínas Proto-Oncogénicas/metabolismo , Linfocitos T/inmunología , Factor de Transcripción AP-1/metabolismo , Regulación hacia Arriba , Animales , Sitios de Unión , ADN/metabolismo , Genes Reporteros , Humanos , Interleucina-2/genética , Células Jurkat , Ratones , Factores de Transcripción NFATC , Regiones Promotoras Genéticas , Unión Proteica , Conformación Proteica , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-rel , Factores de Transcripción/metabolismoRESUMEN
Nuclear transcription assays were performed with isolated nuclei from human peripheral blood T lymphocytes stimulated with phytohemagglutinin and phorbol myristate acetate to determine the kinetics of transcriptional activity of various genes occurring in T cell activation. Although silent in resting T cells, the genes encoding c-myc and the interleukin 2 (IL-2) receptor were induced early, preceding gamma interferon (IFN-gamma), IL-2, and transferrin receptor gene transcription. Transcriptional activity of these genes fell after their respective peaks, indicating that the expression of these genes is a transient event during T cell activation. With the exception of the transferrin receptor gene, the kinetics of induction of these genes were not altered by concentrations of cycloheximide that inhibited protein synthesis. These data indicate that the induction of genes encoding c-myc, IL-2, IL-2 receptor, and IFN-gamma occur independently of the sequential production of the proteins they encode.
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Regulación de la Expresión Génica , Linfocitos T/inmunología , Diferenciación Celular , División Celular , Humanos , Interferón gamma/genética , Interleucina-2/genética , Activación de Linfocitos , Oncogenes , Receptores de Superficie Celular/genética , Receptores Inmunológicos/genética , Receptores de Interleucina-2 , Receptores de Transferrina , Linfocitos T/citología , Transcripción GenéticaRESUMEN
Monoclonal antibodies J5, VIL-A1, and BA-3, known to react with the common acute lymphoblastic leukemia antigen (CALLA) were found to specifically stain normal human polymorphonuclear neutrophils (PMN). The antigen detected on PMN had a molecular weight (95,000-110,000 mol wt) close to that of CALLA (95,000-100,000 mol wt) and thus these surface membrane antigens are likely related, if not identical. The fluorescent staining intensity of PMN is comparable to that of CALLA-positive leukemic cells and the presence of PMN in patient samples could potentially produce false-positive results in diagnosis.
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Antígenos de Neoplasias/análisis , Leucemia Linfoide/inmunología , Neutrófilos/inmunología , Adulto , Animales , Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/inmunología , Reacciones Falso Positivas , Técnica del Anticuerpo Fluorescente , Humanos , Leucemia Linfoide/diagnóstico , Linfoma/inmunología , Ratones , NeprilisinaRESUMEN
Interleukin 2 promotes proliferation of T cells by virtue of its interaction with a high-affinity cell surface receptor. This receptor is a 55,000 mol wt glycoprotein that is also recognized by the murine monoclonal antibody, anti-Tac. Quantitative binding studies with radiolabeled IL-2 and anti-Tac, however, initially indicated far more antibody binding sites per cell than IL-2 binding sites. Extension of the IL-2 binding analysis to concentrations several thousand-fold higher than that necessary for the T cell proliferative response demonstrated the existence of a class (or classes) of low-affinity IL-2 binding sites. Inclusion of the low-affinity IL-2 binding greatly reduced the quantitative discrepancy in the ligand binding assays. That the low-affinity binding, as well as the high-affinity interaction, was associated with the Tac molecule was indicated by the finding that the antibody could substantially or totally block the entire spectrum of IL-2 binding and by the finding that IL-2 could in turn block all radiolabeled anti-Tac binding. The low-affinity sites were found on activated T cells, several human and murine T cell lines and two examples of Tac-positive B cells. The physiological role of the low-affinity IL-2 binding sites and the molecular changes in the Tac protein that give rise to the affinity differences remain open to investigation.
Asunto(s)
Antígenos de Superficie/inmunología , Interleucina-2/metabolismo , Receptores de Antígenos de Linfocitos T/análisis , Receptores Inmunológicos/análisis , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/fisiología , Sitios de Unión de Anticuerpos , Unión Competitiva , Línea Celular , Humanos , Interleucina-2/fisiología , Cinética , Activación de Linfocitos , Ratones , Receptores de Interleucina-2 , Linfocitos T Citotóxicos/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis TumoralRESUMEN
Considerable controversy and uncertainty have surrounded the biological function of the Human Immunodeficiency Virus (HIV)-1 nef gene product. Initial studies suggested that this early, nonstructural viral protein functioned as a negative regulatory factor; thus, it was proposed to play a role in establishing or maintaining viral latency. In contrast, studies in Simian Immunodeficiency Virus (SIV)mac-infected rhesus monkeys have suggested that Nef is not a negative factor but rather plays a central role in promoting high-level viral replication and is required for viral pathogenesis in vivo. We sought to define a tissue culture system that would approximate the in vivo setting for virus infection in order to assess the role of HIV-1 Nef in viral replication. We show that infection of mitogen-activated peripheral blood mononuclear cells (PBMC) with Nef+ HIV results in enhanced replication as evidenced by earlier gag p24 expression when compared with infections performed with nef mutant viruses. Moreover, when unstimulated freshly isolated PBMC are infected with Nef+ and Nef- viruses and then subsequently activated with mitogen, the Nef-induced difference in viral replication kinetics is even more pronounced, with the Nef- viruses requiring much more time in culture for appreciable growth. A positive effect of Nef on viral replication was also observed in primary macrophages infected with a recombinant of YU-2, a patient-derived molecular clone with macrophage tropism. These positive effects of Nef on viral replication are dependent on the initial multiplicity of infection (MOI), in that infections of unstimulated PBMC at low MOI are most dependent upon intact nef for subsequent viral growth. We now provide evidence that the Nef+ HIV is more infectious than Nef- HIV from both a tissue culture infectious dose analysis, and a single-cell HIV infection assay. In the latter case, we demonstrate that infection with equivalent doses of HIV based on virion-associated gag p24 yields five- to sixfold more infected cells if Nef+ viral stocks were used. Furthermore, we find that the differential infectivity is not dependent on CD4 down-regulation as Nef+ virus produced from transfected COS cells lacking CD4 is also more infectious. However, normalization of PBMC infections to equivalent infectivity between that of the Nef+ and Nef- viruses continues to reveal delayed viral replication in the absence of Nef, suggesting that secondary viral spread in PBMC is also enhanced in Nef+ infections. We demonstrate this directly by showing a 13-15-fold increase in infectivity of PBMC-derived Nef+ HIC.(ABSTRACT TRUNCATED AT 400 WORDS)
Asunto(s)
Productos del Gen nef/genética , VIH-1/genética , Macrófagos/microbiología , Linfocitos T/microbiología , Replicación Viral , Antígenos CD4/análisis , Línea Celular , Transformación Celular Viral , Células Cultivadas , Vectores Genéticos , VIH-1/patogenicidad , VIH-1/fisiología , Humanos , Provirus/fisiología , Linfocitos T/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia HumanaRESUMEN
Human interleukin 2 (IL-2) receptor cDNA derived from HUT 102B2 cells was stably expressed in murine L cells. These L cell transfectants (a) displayed surface receptors of the aberrant size of the IL-2 receptors on HUT 102B2 cells, (b) did not respond to exogenous IL-2 with augmented proliferation, and (c) expressed low affinity but not high affinity receptors for IL-2.
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ADN/genética , Interleucina-2/inmunología , Receptores Inmunológicos/genética , Animales , Vectores Genéticos , Humanos , Células L/inmunología , Ratones , Receptores Inmunológicos/biosíntesis , Receptores Inmunológicos/metabolismo , Receptores de Interleucina-2 , Virus 40 de los Simios/genética , TransfecciónRESUMEN
A human suppressor T cell maintained in long-term culture with conditioned medium containing interleukin 2 elaborates a suppressor factor(s) that specifically inhibits human polyclonal B cell immunoglobulin biosynthesis. This soluble immune suppressor supernate of immunoglobulin production (CTC-SISS-B) shares a number of features with the previously described suppressive mediator elaborated by concanavalin A-activated human peripheral T cells (SISS-B) including: (a) the inhibition by a noncytotoxic mechanism, (b) the suppression of immunoglobulin biosynthesis either through direct action on the B cell or indirect action via the monocyte, (c) the loss of inhibition in the presence of the monosaccharide L-rhamnose, (d) the elaboration by cells irradiated with 500 ro 2,000 rad, and (e) molecular weights of 60,000--90,000. Furthermore, the suppression by this mediator appears to be specific for B cell immunoglobulin production in that CTC-SISS B has no effect on T cell proliferation to mitogens, antigens, an allogeneic cells or on T cell-mediated cytotoxicity. These data indicate that one possible mechanism of suppressor T cell inhibition of human immunoglobulin production is via the generation of a lectinlike suppressor lymphokine that interacts with defined saccharide determinants on the cell surface of either the B cell or monocyte.
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Linfocitos B/inmunología , Inmunoglobulinas/biosíntesis , Linfocitos T Reguladores/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos , Anticuerpos Monoclonales , Cromatografía en Gel , Medios de Cultivo , Citotoxicidad Inmunológica , Fucosa/farmacología , Galactosa/farmacología , Humanos , Cinética , Fitohemaglutininas/farmacología , Conejos , Ramnosa/farmacología , Solubilidad , Timidina/metabolismo , Factores de TiempoRESUMEN
Prior experiments in explants of human lymphoid tissue have demonstrated that human immunodeficiency virus type 1 (HIV-1) productively infects diverse cellular targets including T cells and tissue macrophages. We sought to determine the specific contribution of macrophages and T cells to the overall viral burden within lymphoid tissue. To block infection of macrophages selectively while preserving infection of T cells, we used viruses deficient for viral protein R (Vpr) that exhibit profound replication defects in nondividing cells in vitro. We inoculated tonsil histocultures with matched pairs of congenic viruses that differed only by the presence of a wild-type or truncated vpr gene. Although these viruses exhibited no reduction in the infection or depletion of T cells, the ability of the Vpr-deficient R5 virus to infect tissue macrophages was severely impaired compared with matched wild-type R5 virus. Interestingly, the Vpr-deficient R5 virus also exhibited a 50% reduction in overall virus replication compared with its wild-type counterpart despite the fact that macrophages represent a small fraction of the potential targets of HIV-1 infection in these tissues. Collectively, these data highlight the importance of tissue macrophages in local viral burden and further implicate roles for CC chemokine receptor 5, macrophages, and Vpr in the life cycle and pathogenesis of HIV-1.