RESUMEN
Sagittal synostosis (SS) is the commonest form of craniosynostosis. Children with sagittal synostosis in Ireland are treated in the National Paediatric Craniofacial Centre (NPCC) in Temple Street Children's University Hospital. This retrospective study analysed the correlation between referral patterns to the unit and age at operation. The notes of 81 patients referred over a 5-year period (April 2008 - April 2013) to the NPCC with non-syndromic SS were reviewed and demographics and referral information were recorded. Of 81 patients reviewed, 60 (74%) were referred before 6 months of age, while 21 (26%) had late referrals. Neonatologists referred 100% of infants before 6 months, paediatricians referred 71%, and GPs 64%. Later referral was associated with a more complex referral pathway, including multiple-steps of referral and unnecessary investigations. Improved clinician knowledge and emphasis on the importance of early referral may lead to a reduction in late referrals.
Asunto(s)
Craneosinostosis/cirugía , Derivación y Consulta/estadística & datos numéricos , Factores de Edad , Niño , Preescolar , Médicos Generales/estadística & datos numéricos , Humanos , Lactante , Irlanda , Neonatólogos/estadística & datos numéricos , Pediatras/estadística & datos numéricos , Estudios RetrospectivosRESUMEN
BACKGROUND: Ankylosing spondylitis is a seronegative rheumatoid condition mainly affecting the axial skeleton. It leads to progressive deformity and stiffening of the spine with an increased risk of vertebral fractures and significant neurological deficits compared to the general population. AIM: This study aimed to evaluate the outcomes of patients with ankylosing spondylitis who sustained acute vertebral fractures over a 10-year period. METHODS: A retrospective review of patient records and radiographic images was performed. Mechanism of injury, fracture type, timing of diagnosis, neurological deficit, management and complications were assessed. RESULTS: Twenty-four patients were included. Most (23) sustained low energy injuries. Five (20%) patients had a delayed diagnosis over 24 h after the time of injury. Twelve (50%) of patients had a neurological deficit at the time of admission and most did not recover. Eighteen (75%) patients underwent surgical stabilisation. There were 19 complications (in 15 patients) following surgery. CONCLUSION: Patients with ankylosing spondylitis are at risk of spinal fracture and associated spinal cord injury after relatively minor trauma. Delayed diagnosis places the patient at risk of neurological compromise, and thus a high index of suspicion is needed when assessing this patient group.
Asunto(s)
Fracturas de la Columna Vertebral/etiología , Espondilitis Anquilosante/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Fracturas de la Columna Vertebral/patología , Espondilitis Anquilosante/patología , Resultado del TratamientoRESUMEN
BACKGROUND: Environmental conditions play a crucial role in mite growth, and optimal environmental control is key in the prevention of airway inflammation in chronic allergic rhinoconjunctivitis or asthma. OBJECTIVE: To evaluate the relationship between building energy performance and indoor mite allergen concentration in a cross-sectional study. METHODS: Major allergen concentration (Der f 1, Der p 1, mite group 2, Fel d 1 and Bla g 2) was determined by quantitative dot blot analysis from mattress and carpet dust samples in five buildings designed for low energy use (LEB) and in six control buildings (CB). Inhabitants had received 4 weeks prior to mite measurement a personal validated questionnaire related to the perceived state of health and comfort of living. RESULTS: Cumulative mite allergen concentration (with Der f 1 as the major contributor) was significantly lower in LEB as compared with CB both in mattresses and in carpets. In contrast, the two categories of buildings did not differ in Bla g 2 and Fel d 1 concentration, in the amount of dust and airborne mould collected. Whereas temperature was higher in LEB, relative humidity was significantly lower than in CB. Perceived overall comfort was better in LEB. CONCLUSIONS: Major mite allergen Der f 1 preferentially accumulates in buildings not specifically designed for low energy use, reaching levels at risk for sensitization. We hypothesize that controlled mechanical ventilation present in all audited LEB may favour lower air humidity and hence lower mite growth and allergen concentration, while preserving optimal perceived comfort.
Asunto(s)
Contaminación del Aire Interior/análisis , Antígenos Dermatofagoides/análisis , Conservación de los Recursos Energéticos , Vivienda , Contaminación del Aire Interior/efectos adversos , Animales , Antígenos Dermatofagoides/efectos adversos , Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos , Lechos/microbiología , Estudios Transversales , Cisteína Endopeptidasas , Pisos y Cubiertas de Piso , Humanos , Humedad , Hipersensibilidad/epidemiología , Encuestas y Cuestionarios , TemperaturaRESUMEN
AIMS: To determine the efficacy of solar disinfection (SODIS) for enteric pathogens and to test applicability of the reciprocity law. METHODS AND RESULTS: Resistance to sunlight at 37 degrees C based on F99 values was in the following order: Salmonella Typhimurium>Escherichia coli>Shigella flexneri>Vibrio cholerae. While F90 values of Salm. Typhimurium and E. coli were similar, F99 values differed by 60% due to different inactivation curve shapes. Efficacy seemed not to be dependent on fluence rate for E. coli stationary cells. Sensitivity to mild heat was observed above a temperature of 45 degrees C for E. coli, Salm. Typhimurium and Sh. flexneri, while V. cholerae was already susceptible above 40 degrees C. CONCLUSIONS: Salmonella Typhimurium was the most resistant and V. cholerae the least resistant enteric strain. The reciprocity law is applicable for stationary E. coli cells irradiated with sunlight or artificial sunlight. SIGNIFICANCE AND IMPACT OF THE STUDY: Escherichia coli might not be the appropriate indicator bacterium to test the efficacy of SODIS on enteric bacteria and the physiological response to SODIS might be different among enteric bacteria. The applicability of the reciprocity law indicates that fluence rate plays a secondary role in SODIS efficacy. Stating inactivation efficacy with T90 or F90 values without showing original data is inadequate for SODIS studies.
Asunto(s)
Desinfección/métodos , Disentería Bacilar/prevención & control , Luz Solar , Purificación del Agua/métodos , Disentería Bacilar/microbiología , Escherichia coli/efectos de la radiación , Calor , Dosis de Radiación , Salmonella typhimurium/efectos de la radiación , Shigella flexneri/efectos de la radiación , Especificidad de la Especie , Rayos Ultravioleta , Vibrio cholerae/efectos de la radiación , Microbiología del Agua , Abastecimiento de AguaRESUMEN
The key to optimizing productivity during industrial fermentations is the ability to rapidly monitor and interpret the physiological state of single microbial cells in a population and to recognize and characterize different sub-populations. Here, a flow cytometry-based method for the reproducible detection of changes in membrane function and/or structure of recombinant E. coli JM101 (pSPZ3) expressing xylene monooxygenase (XMO), was developed. XMO expression led to compromised but not permeabilized cell membranes. This was deduced from the fact that recombinant cells only stained with ethidium bromide (EB) and not with propidium iodide (PI). During the glucose-limited fedbatch cultivation, an increase from 25% to 95% of EB-stained cells was observed, occurring between 2 and 5 h after induction. Control experiments confirmed that this increase was due to the recombinant protein production and not caused by any possible effects of varying substrate availability, high cell density, plasmid replication or the presence of the inducing agent. We hypothesize that the integration of the recombinant protein into the cell membrane physically disrupted the functionality of the efflux pumps, thus resulting in EB-staining of the recombinant cells. This method enabled us to detect changes in the physiological state of single cells 2-4 h before other indications of partial cell damage, such as unbalanced growth, acetate accumulation and an increased CO(2) production rate, were observed. This method therefore shows promise with respect to the further development of an early-warning system to prevent sudden productivity decreases in processes with recombinant E. coli expressing heterologous membrane proteins.
Asunto(s)
Reactores Biológicos , Carbono/química , Membrana Celular/metabolismo , Escherichia coli/metabolismo , Citometría de Flujo/instrumentación , Citometría de Flujo/métodos , Acetatos/química , Membrana Celular/química , Medios de Cultivo/química , Medios de Cultivo/farmacología , Proteínas de Escherichia coli/química , Etidio/farmacología , Fermentación , Colorantes Fluorescentes/farmacología , Glucosa/metabolismo , Microbiología Industrial/instrumentación , Microbiología Industrial/métodos , Proteínas de la Membrana/química , Microscopía Fluorescente , Oxigenasas/metabolismo , Propidio/química , Propidio/farmacología , Proteínas Recombinantes/química , Factores de TiempoRESUMEN
Alum-adsorbed BBG2Na, a recombinant vaccine derived in part from the respiratory syncytial virus (RSV) subgroup A G protein, induced moderate antibody titers after 1 immunization in 1-week-old mice but conferred complete lung protection upon RSV challenge. The anti-BBG2Na IgG1-IgG2a neonatal isotype profile was suggestive of dominant Th2 responses compared with those in adults. Formulation of BBG2Na with a Th1-driving adjuvant efficiently shifted neonatal responses toward a more balanced and adultlike IgG1-IgG2a profile without compromising its protective efficacy. BBG2Na-induced protective immunity was maintained even after early life immunization in the presence of high titers of maternal antibodies. Under these conditions, the protective efficacy (86%-100%) reflected the high capacity of the nonglycosylated G2Na immunogen to escape inhibition by RSV-A-induced maternal antibodies. Thus, immunization with BBG2Na protected against viral challenge despite neonatal immunologic immaturity and the presence of maternal antibodies, two major obstacles to neonatal RSV vaccine development.
Asunto(s)
Proteína HN , Infecciones por Virus Sincitial Respiratorio/prevención & control , Vacunación , Proteínas Virales/uso terapéutico , Vacunas Virales/uso terapéutico , Adyuvantes Inmunológicos , Animales , Animales Recién Nacidos , Inmunidad Materno-Adquirida , Ratones , Ratones Endogámicos BALB C , Vacunas Sintéticas/uso terapéutico , Proteínas del Envoltorio ViralRESUMEN
The transfer of maternal antibodies to the offspring and their inhibitory effects on active infant immunization is an important factor hampering the use of certain vaccines, such as measles or respiratory syncytial virus vaccine, in early infancy. The resulting delay in protection by conventional or novel vaccines may have significant public health consequences. To define immunization approaches which may circumvent this phenomenon, experiments were set up to further elucidate its immunological bases. The influence of maternal antibodies on antibody and T cell responses to measles hemagglutinin (MV-HA) were analyzed following MV-HA immunization of pups born to immune or control BALB/c mothers using four different antigen delivery systems: live or inactivated conventional measles vaccine, a live recombinant canarypox vector and a DNA vaccine. High levels (> 5 log10) of maternal anti-HA antibodies totally inhibited antibody responses to each of the vaccine constructs, whereas normal antibody responses were elicited in presence of lower titers of maternal antibodies. However, even high titers of maternal antibodies affected neither the induction of vaccine-specific Th1/Th2 responses, as assessed by proliferation and levels of IFN-gamma and IL-5 production, nor CTL responses in infant mice. On the basis of these unaltered T cell responses, very early priming and boosting (at 1 and 3 weeks of age, respectively) with live measles vaccine allowed to circumvent maternal antibody inhibition of antibody responses in pups of immune mothers. This was confirmed in another immunization model (tetanus toxoid). It suggests that effective vaccine responses may be obtained earlier in presence of maternal antibodies through the use of appropriate immunization strategies using conventional or novel vaccines for early priming.
Asunto(s)
Anticuerpos/inmunología , Inmunidad Materno-Adquirida , Linfocitos T/inmunología , Vacunación , Animales , Femenino , Inmunidad Celular , Intercambio Materno-Fetal , Ratones , EmbarazoRESUMEN
Presence of maternally-derived antibodies at time of immunization is known to often interfere with active infant immunization, although with variable degrees of clinical significance. In order to progressively decipher the rules that form the basis for these inhibitory effects on infant vaccine responses, two antigens (measles, tetanus) and various antigen presentation systems were evaluated in murine early life immunization models either in absence or presence of maternal antibodies. Both conventional (proteins, conjugate vaccines) and new (live viral vectors, DNA plasmids) antigen presentation systems were found to be similarly susceptible to the inhibitory influence of maternal antibodies. Factors emerging as crucial determinants of maternal antibody-mediated effects on responses to both live and non-live vaccines include (i) the level of maternal antibodies present at immunization, (ii) the use of distinct vaccines in mothers and pups and (iii) their distinct influence on B cell and T cell vaccine responses.
Asunto(s)
Anticuerpos Antibacterianos/inmunología , Anticuerpos Antivirales/inmunología , Inmunidad Materno-Adquirida/inmunología , Vacunas/farmacología , Animales , Presentación de Antígeno/inmunología , Antígenos/inmunología , Linfocitos B/inmunología , Femenino , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Linfocitos T/inmunología , Toxoide Tetánico/inmunología , Toxoide Tetánico/farmacología , Vacunas/inmunología , Vacunas Conjugadas/inmunología , Vacunas Conjugadas/farmacologíaRESUMEN
We have recently shown that neonatal responses to a pannel of vaccine antigens and presentation systems differed qualitatively from adult responses by a bias towards a TH2 pattern. Here we report that a selected adjuvant comprising block copolymers in a water-in-oil emulsion can induce balanced TH1/TH2 responses in BALB/c mice primed at 1 week of age with an immunodominant tetanus peptide vaccine. However, using this specific TH1-driving adjuvant only at time of boosting was not sufficient to fully circumvent the persisting influence of TH2-biased neonatal responses. Unexpectedly also, a significant local toxicity was observed in newborn and young mice, whereas only mild reactions occurred in adults. Thus, although the induction of strong TH1 responses in the neonatal period can be achieved using specific adjuvants, through modulation of the immunological environment present at time of priming, whether such immunization strategies would be safe in the neonatal period remains to be demonstrated. These observations should be taken into consideration in the development of novel vaccines that will have to be already effective early in life.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Compuestos de Alumbre/farmacología , Animales Recién Nacidos/inmunología , Vacunas Bacterianas/inmunología , Citocinas/biosíntesis , Poloxaleno/farmacología , Toxina Tetánica/inmunología , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Células Th2/efectos de los fármacos , Células Th2/metabolismo , Animales , Memoria Inmunológica/inmunología , Interferón gamma/biosíntesis , Interleucina-4/biosíntesis , Interleucina-5/biosíntesis , Ratones , Ratones Endogámicos BALB C , Células TH1/inmunología , Células Th2/inmunologíaRESUMEN
Induction of neonatal immune responses to vaccine antigens is believed to be of limited efficacy because of immune immaturity and particular susceptibility to tolerogenic signals during this period of life. To characterize particular features of neonatal immune responses to vaccine antigens, we assessed the capacity of BALB/c mice at different stages of immunological maturation to respond to a selection of vaccine antigens and presentation systems. Significant B and T cell responses to vaccine antigens (tetanus and measles virus peptides, tetanus toxoid, live viral attenuated measles virus, canarypox recombinant measles vector or bacillus Calmette-Guérin) were obtained as early as the first week of life. However, these neonatal responses differed qualitatively from adult responses by a decreased IgG2a/IgG1 ratio of vaccine-specific antibodies, the secretion of significantly higher interleukin-5 and lower interferon-gamma levels by vaccine-specific T cells and an impaired induction of cytotoxic T cell precursors. This pattern of biased Th2 versus Th1 responses induced upon early exposure to vaccines was not reversed by decreasing the doses of vaccine antigens. It did not disappear with aging and was still reflected in adult responses to booster immunization with the corresponding antigen. Thus, neonatal immunization can induce significant vaccine specific responses with a predominance of a Th2 pattern which can persist in boosted adult mice.
Asunto(s)
Envejecimiento/inmunología , Animales Recién Nacidos/inmunología , Formación de Anticuerpos , Inmunización Secundaria , Células Th2/inmunología , Vacunas/inmunología , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Citotoxicidad Inmunológica , Epítopos , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Th2/metabolismoRESUMEN
The injection of semi-allogeneic F1 spleen cells into newborn mice of a parental strain induces a state of immune tolerance characterized by anti-donor CTL unresponsiveness and the appearance of a transient SLE-like autoimmune syndrome associating autoantibody production, hypergammaglobulinemia, splenomegaly and glomerulonephritis. Our previous experiments have demonstrated that host Th2-like CD4+ T lymphocytes activate donor F1 B cells persisting in the host to produce autoantibodies, and that this cellular interaction relies on the presence of alloMHC class II molecules on donor B cells. In order to investigate the role and the involvement of MHC alloantigens in the cellular T(host)-B(donor) interaction, newborn C57BL/6 (B6) mice were injected with F1 spleen cells differing from the host at the level of defined portions of the MHC class I (K) or class II (I-A and I-E) molecules. B6 mice injected at birth with spleen cells from different F1 strains were tolerant to each alloantigen (alloAg) tested, as assessed by specific anti-donor CTL unresponsiveness. However, the SLE-like autoimmune syndrome only developed in B6 mice injected at birth with F1 spleen cells differing at the level of MHC class II I-A or I-E molecules. Autoantibodies appeared later in B6 mice neonatally tolerized to I-E alloAg than those detected in B6 mice neonatally tolerized to I-A alloAg. These results show that the SLE-like autoimmune disease that develops concomitantly to neonatally-induced tolerance to alloAg is the consequence of cognate T host-B donor cellular interactions triggered by even minute differences in the MHC class II I-A or MHC class II I-E molecules.
Asunto(s)
Animales Recién Nacidos/inmunología , Presentación de Antígeno , Enfermedades Autoinmunes/inmunología , Modelos Animales de Enfermedad , Genes MHC Clase II , Antígenos de Histocompatibilidad Clase II/inmunología , Tolerancia Inmunológica , Isoantígenos/inmunología , Lupus Eritematoso Sistémico/inmunología , Cooperación Linfocítica , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Autoanticuerpos/biosíntesis , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/patología , Linfocitos B/inmunología , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Glomerulonefritis/etiología , Antígenos de Histocompatibilidad Clase II/genética , Hibridación Genética , Hipergammaglobulinemia/etiología , Inmunoterapia Adoptiva/efectos adversos , Interferón gamma/biosíntesis , Interleucina-5/biosíntesis , Isoantígenos/administración & dosificación , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Bazo/citología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Citotóxicos/inmunología , Células Th2/inmunologíaAsunto(s)
Muerte Fetal , Infanticidio/legislación & jurisprudencia , Seguro por Accidentes/legislación & jurisprudencia , Responsabilidad Legal , Lesiones Prenatales , Accidentes de Tránsito/legislación & jurisprudencia , Adulto , Comparación Transcultural , Femenino , Viabilidad Fetal/fisiología , Humanos , Recién Nacido , Masculino , Maltrato Conyugal/legislación & jurisprudencia , Suiza , Estados UnidosRESUMEN
During 1986 and 1988, selected farms in all of the major carrot-growing counties of Michigan were surveyed to determine the extent of infestation by Heterodera carotae and Meloidogyne hapla. Both species were found in all eight counties surveyed, but not on all farms. Heterodera carotae was recovered from 67.4% of the fields surveyed. Meloidogyne hapla was detected in 24.8% of the samples and from 69.8% of the fields. In most cases, H. carotae and M. hapla occurred in the same field.
RESUMEN
The relative importance of polyclonal B cell activation has been studied in relation to the development of autoantibodies in human African trypanosomiasis. In 34 patients investigated before specific treatment a broad expression of the B cell repertoire was observed including the production of anti-hapten (FITC, Penicillin, Phosphorylcholin) antibodies, of high levels of antibodies against some heterologous protein antigens (ovalbumin and tetanus toxoid) and of autoantibodies. Anti-ssDNA antibodies were detected in 84% of the patients and anti-IgG rheumatoid factors in 88%. Anti-striated muscle and anti-smooth muscle antibodies were also observed in 57 and 63% of the patients. Correlation analysis indicated that the formation of anti-DNA antibodies is associated with polyclonal B cell activation but probably depends on an additional B cell stimulation by released DNA or cross-reacting antigens. Anti-immunoglobulin antibodies are closely correlated with polyclonal B cell activation and their production is likely to reflect the high frequency of anti-IgG B cell precursors in the normal human B cell repertoire. The significance of these observations in relation to the pathological expression of trypanosomiasis should be particularly considered in the generation of immune complexes either in circulating blood or locally at the sites of parasite destruction.
Asunto(s)
Autoanticuerpos/biosíntesis , Linfocitos B/inmunología , Tripanosomiasis Africana/inmunología , Anticuerpos Antinucleares/biosíntesis , ADN de Cadena Simple , República Democrática del Congo , Haptenos/inmunología , Humanos , Inmunoglobulinas/biosíntesis , Músculos/inmunología , Ovalbúmina/inmunología , Albúmina Sérica Bovina/inmunología , Trypanosoma brucei brucei/inmunologíaRESUMEN
The possible occurrence of immune complexes (IC) in serum and in cerebrospinal fluid (CSF) has been studied in 36 patients with African trypanosomiasis (Trypanosoma brucei gambiense). In serum, very high levels of IC were detectable by the (125)I-C1q-binding and by the conglutinin-binding assays with positive results in 94 and 87%, respectively, of untreated patients. Circulating IC were found in both early and late stages of the disease, without significant quantitative differences; their size was 15-25S. There was a significant negative correlation between C3 values and C1qBA. Our studies suggest that circulating IC occurring during trypanosomiasis may be the expression of a polyclonal B cell activation. Indeed, there was a significant correlation (P < 0.001) between the levels of circulating IC and either the levels of IgM (mean value 12.5+/-7.2 mg/ml) or with the levels of rheumatoid factor-like antiimmunoglobulin antibodies that were detected by solid phase radioimmunoassay in 74% of the patients.IC were detected in 31 of 35 CSF samples, with a marked elevation in patients with definite involvement of the central nervous system as compared with earlier stages of sleeping sickness. The occurrence of IC in CSF was not related to an impairment of the blood-brain barrier as shown by analysis of CSF/serum albumin ratios. The level of IC in CSF did not correlate with the serum level and, therefore, circulating IC do not appear to cross efficiently an unimpaired blood-brain barrier. The analysis of IgG, IgM, and albumin concentrations in serum and CSF demonstrates a marked intracerebral immunoglobulin synthesis in patients with manifestations of meningoencephalitis. There was a correlation between CSF-C1q binding assay and this local IgG synthesis. These data are consistent with a local formation of IC in CSF in patients with active meningoencephalitis. The results obtained in eight patients followed during therapy suggest that the presence of IC in CSF may be an indicator of a continuing central nervous system disease and that the quantitation of CSF-IC may be useful for monitoring patient care.
Asunto(s)
Complejo Antígeno-Anticuerpo/líquido cefalorraquídeo , Tripanosomiasis Africana/inmunología , Anticuerpos/análisis , Linfocitos B/inmunología , Complemento C3/análisis , Humanos , Inmunoglobulinas/líquido cefalorraquídeo , Activación de Linfocitos , Trypanosoma brucei gambiense/inmunología , Tripanosomiasis Africana/líquido cefalorraquídeo , Tripanosomiasis Africana/tratamiento farmacológicoRESUMEN
In vitro incubation of peritoneal macrophages from normal, peptone-stimulated mice with levamisole (1-100 microM) for 1 and 22 h had no effect on either phagocytosis of particulate material (sheep erythrocytes, zymosan) or cellular levels and release of lysosomal enzymes (beta-D-glucuronidase, cathepsin D). By contrast, levamisole 1 and 5 mM dramatically increased enzyme release while inhibiting phagocytosis. In some experiments, however, these high concentrations of levamisole caused an elevated cell mortality. When incubation was extended to 72 h, a decrease of both phagocytosis and enzyme release was observed. The catabolism of endocytosed antigens (sheep erythrocytes, human gammaglobulin) was not at all or only slightly modified depending upon the antigen. The cellular level of cyclic AMP remained unchanged in all experiments. In vivo exposure of macrophages to levamisole (2.5 and 10 mg/kg/day i.p. for 3 days) produced a dose-dependent increase in processing of endocytosed antigens as shown by an enhanced transfer of initially endocytosed material to the macrophage plasma membrane. The other parameters were not modified. The immunogenicity of erythrocytes, when endocytosed by levamisole-treated macrophages and transferred into unsensitized recipients, was increased in some in vivo experiments.
Asunto(s)
Levamisol/farmacología , Macrófagos/efectos de los fármacos , Animales , Antígenos/metabolismo , AMP Cíclico/metabolismo , Eritrocitos/inmunología , Inmunidad/efectos de los fármacos , Técnicas In Vitro , Ratones , Fagocitosis/efectos de los fármacos , Ovinos/inmunologíaRESUMEN
The catabolism of completely endocytosed isologous and heterologous gamma-globulins by mouse macrophages was studied in vitro. Mouse, human, and rabbit 125-I-IgG were coupled to mouse, human, or sheep erythrocytes either as antibodies or by covalent binding. They were exposed to macrophages for 1 hr and the non-endocytosed erythrocytes were then removed with a Ficoll gradient centrifugation. Catabolism was evaluated after 2, 5, and 18 hr in culture by measuring the radioactivity released into the culture medium as well as the radioactivity that remained associated with cells. It was found that all iota-globulins were catabolized in a similar fashion, and that the type of carrier erythrocytes (isologous or heterologous) had no influence on catabolism. Some of the material that remained associated with macrophages was on the cell membrane and could be removed by trypsin. Some of the material that was released by macrophages was completely degraded but some was either not degraded or only partially degraded. Sucrose density gradient analysis and SDS-polyacrylamide gel electrophoresis showed that this material had kept some physical properties of native iota-globulins. It was also found with the antigen-binding inhibition test and incubation with erythrocytes that the released material contained molecules carrying Fab determinants and was able to bind specifically to erythrocytic antigens. Taken together, these observations show that iota-globulins phagocytosed in the form of antigen-antibody complexes are only incompletely degraded and that the material associated with plasma membrane of macrophages or found in the culture medium is a product of cell catabolism.