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1.
Transpl Infect Dis ; 18(4): 628-33, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27214585

RESUMEN

Recurrent Clostridium difficile infection (CDI) is a consequence of intestinal dysbiosis and is particularly common following hematopoietic stem cell transplantation (HSCT). Fecal microbiota transplantation (FMT) is an effective method of treating CDI by correcting intestinal dysbiosis by passive transfer of healthy donor microflora. FMT has not been widely used in immunocompromised patients, including HSCT recipients, owing to concern for donor-derived infection. Here, we describe initial results of an FMT program for CDI at a US HSCT center. Seven HSCT recipients underwent FMT between February 2015 and February 2016. Mean time post HSCT was 635 days (25-75 interquartile range [IQR] 38-791). Five of the patients (71.4%) were on immunosuppressive therapy at FMT; 4 had required long-term suppressive oral vancomycin therapy because of immediate recurrence after antibiotic cessation. Stool donors underwent comprehensive health and behavioral screening and laboratory testing of serum and stool for 32 potential pathogens. FMT was administered via the naso-jejunal route in 6 of the 7 patients. Mean follow-up was 265 days (IQR 51-288). Minor post-FMT adverse effects included self-limited bloating and urgency. One patient was suspected of having post-FMT small intestinal bacterial overgrowth. No serious adverse events were noted and all-cause mortality was 0%. Six of 7 (85.7%) patients had no recurrence; 1 patient recurred at day 156 post FMT after taking an oral antibiotic and required repeat FMT, after which no recurrence has occurred. Diarrhea was improved in all patients and 1 patient with gastrointestinal graft-versus-host disease was able to taper off systemic immunosuppression after FMT. With careful donor selection and laboratory screening, FMT appears to be a safe and effective therapy for CDI in HSCT patients and may confer additional benefits. Larger studies are necessary to confirm safety and efficacy and explore other possible effects.


Asunto(s)
Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/terapia , Diarrea/terapia , Disbiosis/terapia , Trasplante de Microbiota Fecal , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Terapia de Inmunosupresión/efectos adversos , Adulto , Anciano , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Infecciones por Clostridium/microbiología , Diarrea/microbiología , Disbiosis/complicaciones , Trasplante de Microbiota Fecal/efectos adversos , Trasplante de Microbiota Fecal/métodos , Trasplante de Microbiota Fecal/mortalidad , Heces/química , Heces/microbiología , Femenino , Microbioma Gastrointestinal/inmunología , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Humanos , Huésped Inmunocomprometido/inmunología , Terapia de Inmunosupresión/métodos , Intestinos/microbiología , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
2.
Transpl Infect Dis ; 17(5): 688-94, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26256692

RESUMEN

BACKGROUND: Although several studies have documented adverse outcomes for vancomycin-resistant Enterococcus (VRE) colonization and infection in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients, data are inadequate for patients undergoing autologous (auto-)HSCT. METHODS: We conducted a retrospective cohort study of 300 consecutive patients receiving an auto-HSCT between 2006 and 2014. Patients had stool cultures for VRE on admission and weekly during hospitalization. RESULTS: Thirty-six percent of patients had VRE gastrointestinal (GI) colonization and 3% developed a VRE bloodstream infection (BSI), all of whom were colonized. VRE strain typing of BSI isolates showed that some patients shared identical patterns. Rates of colonization and BSI in colonized patients were similar to simultaneous patients undergoing allo-HSCT, except that the latter had a higher rate of colonization at admission. A diagnosis of lymphoma was associated with an increased risk of colonization. VRE BSI was associated with longer lengths of stay and possibly higher costs, but no decrease in overall survival, and colonized patients had no VRE infections during the year following discharge. Repeat stool cultures in patients subsequently undergoing allo-HSCT suggested that most, if not all, VRE-positive auto-HSCT patients lose their detectable GI colonization within a few months of discharge. CONCLUSION: VRE colonization is frequent but carries a low risk for infection in patients undergoing auto-HSCT. However, these patients can serve as reservoirs for transmission to higher risk patients. Moreover, patients may remain colonized if proceeding to an allo-HSCT shortly after auto-HSCT, potentially increasing the risk of the allogeneic procedure.


Asunto(s)
Bacteriemia/etiología , Enterococcus/aislamiento & purificación , Infecciones por Bacterias Grampositivas/etiología , Trasplante de Células Madre Hematopoyéticas , Resistencia a la Vancomicina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Bacteriemia/inmunología , Heces/microbiología , Femenino , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/inmunología , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Trasplante Autólogo , Adulto Joven
4.
J Clin Invest ; 69(2): 394-404, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7035495

RESUMEN

The opsonophagocytic requirements of human sera containing endogenous complement for a variety of type Ia, and group B streptococcal strains were defined. Significant reduction (>==90%) in colony-forming units was noted after a 40-min incubation for the highly encapsulated, mouse-passed prototype strain 090 by sera containing moderate to high concentrations of antibody to type Ia polysaccharide (mean, 16.5 mug/ml), whereas bacterial growth occurred in 25 sera with low levels of specific antibody (mean, 2.1 mug/ml). This absolute requirement for a critical amount of specific antibody in promoting opsonophagocytic killing of strain 090 was not found when 18 fresh clinical type Ia isolates were tested. In antibody-deficient and agammaglobulinemic sera, respectively, mean reductions in colony-forming units of 94 and 95% were seen for fresh clinical isolates, whereas strain 090 was not killed by polymorphonuclear leukocytes in the presence of these sera. All strains required a considerable amount of specific antibody for alternative pathway-mediated opsonophagocytosis. That opsonophagocytic killing of clinical type Ia isolates was mediated by the classical pathway in a nonantibody-dependent fashion was shown when MgEGTA chelation of agammaglobulinemic serum or use of serum deficient in C2 resulted in bacterial growth. The addition of C2 to C2-deficient serum restored bactericidal activity of this serum. These experiments indicate that substances other than the exposed surface of the type Ia capsular polysaccharide initiate classical pathway-mediated opsonophagocytosis of clinical isolates of type Ia, group B streptococci by human sera in the absence of immunoglobulin. Perhaps, a deficiency in classical complement pathway function is critical to the susceptibility of neonates to type Ia, group B streptococcal disease.


Asunto(s)
Anticuerpos Antibacterianos/fisiología , Activación de Complemento , Vía Clásica del Complemento , Proteínas Opsoninas/fisiología , Fagocitosis , Animales , Anticuerpos Antibacterianos/inmunología , Especificidad de Anticuerpos , Complemento C2/deficiencia , Cobayas , Humanos , Ratones , Ratones Endogámicos , Proteínas Opsoninas/inmunología , Polisacáridos Bacterianos/inmunología , Polisacáridos Bacterianos/fisiología , Conejos , Infecciones Estreptocócicas/etiología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/fisiopatología , Streptococcus agalactiae/inmunología , Streptococcus agalactiae/patogenicidad , Virulencia
5.
Pediatrics ; 65(6): 1110-4, 1980 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6154921

RESUMEN

Admission specimens of CSF, serum, and urine from 67 patients with proved group B streptococcal (GBS) bacteremia and/or meningitis were evaluated by countercurrent immunoelectrophoresis (CIE). Group B and type-specific antigens were detected in 81% of CSF, 63% of serum, and 96% of concentrated urine specimens by CIE. Each of 26 infants with meningitis from whom all three body fluids were available and ten with bacteremia from whom both serum and urine were collected at admission had GBS antigens detected by CIE in at least one specimen. No false positive reactions were observed. Among patients with type III, GBS meningeal infection, fatal outcome or neurologic sequelae were significantly correlated with concentration of type III antigen in admission CSF and duration of antigenuria when compared to normal survivors (P = less than .05, Mann-Whitney U tests). CIE appears to be a useful diagnostic and prognostic tool for infants with GBS infection if admission specimens from more than one source are examined and appropriately high-titered antisera are employed for testing.


Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Contrainmunoelectroforesis , Inmunoelectroforesis , Infecciones Estreptocócicas/inmunología , Streptococcus agalactiae/inmunología , Líquidos Corporales/inmunología , Dextranos , Estudios de Evaluación como Asunto , Humanos , Lactante , Meningitis/etiología , Meningitis/inmunología , Sepsis/etiología , Sepsis/inmunología
6.
Pediatrics ; 60(4): 473-6, 1977 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-333366

RESUMEN

Cultures from the vagina, pharynx, and anal canal of 100 healthy girls, 2 months through 15 years of age, were examined for the presence of group B streptococci. Of the 100 participants, 20% were colonized at one or more of these three sites. Pharyngeal colonization was detected in 15% of the girls under 11 years of age and in 5% of those over 11 years of age. Colonization at anogenital sites were observed in 19% of participants under 3 years of age, in 25% of those 11 years of age and older, and in only 4% of those between the ages of 3 and 10 years (P less than .025). The concentration of serum antibody directed against the polysaccharide capsular antigen isolated from type III, group B Streptococcus appeared, in part, to be related to increasing age.


Asunto(s)
Infecciones Estreptocócicas/epidemiología , Adolescente , Factores de Edad , Anticuerpos Antibacterianos/análisis , Enfermedades del Ano/etiología , Niño , Preescolar , Femenino , Humanos , Lactante , Enfermedades Faríngeas/etiología , Infecciones Estreptocócicas/complicaciones , Streptococcus agalactiae/aislamiento & purificación , Enfermedades Vaginales/etiología
7.
Transplant Proc ; 45(2): 792-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23267784

RESUMEN

Invasive fungal infections are a significant complication of solid organ transplantation. Here we report the first case of concurrent invasive pulmonary fungal infection caused by Aspergillus fumigatus and Mucor species in a heart transplant recipient. Polymicrobial mold infection is rare but should be considered in solid organ transplant recipients who fail to respond to initial antifungal therapy targeting a single organism. It is also of interest that in addition to potent immunosuppression and prolonged voriconazole therapy, possible airway fungal colonization following hurricane Katrina cleaning efforts might have contributed to this dual invasive mold infection.


Asunto(s)
Microbiología del Aire , Cardiomiopatía Dilatada/cirugía , Tormentas Ciclónicas , Exposición a Riesgos Ambientales , Trasplante de Corazón/inmunología , Inmunosupresores/efectos adversos , Aspergilosis Pulmonar Invasiva/microbiología , Mucormicosis/microbiología , Antifúngicos/uso terapéutico , Trasplante de Corazón/efectos adversos , Humanos , Aspergilosis Pulmonar Invasiva/diagnóstico , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Aspergilosis Pulmonar Invasiva/inmunología , Masculino , Persona de Mediana Edad , Mucormicosis/diagnóstico , Mucormicosis/tratamiento farmacológico , Mucormicosis/inmunología , Pirimidinas/uso terapéutico , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Triazoles/uso terapéutico , Voriconazol
8.
J Clin Microbiol ; 12(3): 442-4, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7012177

RESUMEN

Although latex agglutination assays for detection of a variety of bacterial antigens in body fluids from patients with systemic infection have been shown to be useful as rapid diagnostic techniques, lack of commercial availability has restricted their application. The Streptex latex test kit for the detection of group B streptococcal (GBS) antigen in admission body fluid specimens was evaluated for sensitivity and specificity in 54 infants with meningitis and in 10 infants with normal cerebrospinal fluid (CSF) parameters. GBS antigen was detected in 22 of 28 (78.6%) CSF specimens by latex agglutination and in 23 of 28 (82.1%) by countercurrent immunoelectrophoresis. Antigen was present in 21 of 28 (latex agglutination) and 19 of 26 (countercurrent immunoelectrophoresis) CSF specimens after the initiation of antimicrobial therapy. Heat-labile factors accounted for nonspecific agglutination reactions with latex suspensions other than group B in 3 of 28 CSF samples from patients with GBS meningitis. These nonspecific reactions were readily eliminated by heating specimens for 10 min at 100 degrees C. Fifteen patients with GBS meningitis had admission serum and urine samples collected in addition to CSF. Antigen was detected by latex agglutination and countercurrent immunoelelectrophoresis in 14 of 15 (93.3%) and 13 of 15 (86.7%) concentrated urine specimens, respectively, and in 12 of 15 (80%) CSF specimens and 4 of 15 (27%) sera by each method. These findings indicate that the Streptex latex test is a rapid, sensitive, and readily available method for detection of GBS antigen in admission body fluid specimens from infants with meningitis.


Asunto(s)
Pruebas de Fijación de Látex , Infecciones Estreptocócicas/diagnóstico , Antígenos Bacterianos/análisis , Antígenos Bacterianos/orina , Líquido Cefalorraquídeo/inmunología , Contrainmunoelectroforesis , Humanos , Lactante , Meningitis/diagnóstico , Streptococcus agalactiae
9.
J Clin Microbiol ; 11(3): 263-5, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6991524

RESUMEN

The usefulness of Phadebact streptococcus reagents for the detection of group B streptococcal antigen in cerebrospinal fluid was evaluated in 54 infants with meningitis and in 22 normal infants. Antigens was detected by slide coagglutination in 19 (82.6%) and by countercurrent immunoelectrophoresis in 20 (87.0%) of 23 cerebrospinal fluid specimens from infants with group B streptococcal meningitis at admission. After initiation of antimicrobial therapy, antigen could be detected in 11 of 19 (by slide coagglutination) and 7 of 18 (by countercurrent immunoelectrophoresis) cerebrospinal fluids. False-positive reactions were noted by slide coagglutination in one infant with S. bovis meningitis and one with group B streptococcal bacteremia without meningitis; none occurred with countercurrent immunoelectrophoresis. The commercial availiability, simplicity, sensitivity (82.6%), and specificity (96.4%) of the Phadebact slide coaggluatination test for detecting group B streptococcal antigen in cerebrospinal fluid suggest that it may be useful for the early and rapid diagnosis of group B streptococcal meningitis.


Asunto(s)
Pruebas de Aglutinación , Antígenos Bacterianos/análisis , Líquido Cefalorraquídeo/inmunología , Contrainmunoelectroforesis , Inmunoelectroforesis , Meningitis/diagnóstico , Infecciones Estreptocócicas/diagnóstico , Streptococcus agalactiae/inmunología , Humanos , Lactante
10.
Antimicrob Agents Chemother ; 10(1): 128-31, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-984744

RESUMEN

The minimal inhibitory concentration of 10 antibiotics for 244 isolates of group B streptococci was determined. Susceptibility to penicillin G, ampicillin, cephalothin, chloramphenicol, and carbenicillin was uniform. Tetracycline and bacitracin resistance among these isolates was frequent (87.5 and 97.9%, respectively). Three strains (1.2%) failed to be inhibited by 100 mug of lincomycin or clindamycin per ml. Susceptibility of these 244 strains to the agents tested was unrelated to source of the isolate, year of isolation, or strain serotype. No apparent change in the suceptibility of group B streptococci to penicillin G has occurred during the past 2 decades.


Asunto(s)
Antibacterianos/farmacología , Streptococcus/efectos de los fármacos , Farmacorresistencia Microbiana , Pruebas de Sensibilidad Microbiana , Infecciones Estreptocócicas/microbiología , Factores de Tiempo
11.
J Infect Dis ; 154(1): 47-54, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3519791

RESUMEN

The role of complement and antibody in the opsonophagocytosis of type II group B streptococci (type II GBS) was defined with sera from healthy adults and two populations with theoretical susceptibility to type II GBS infection--neonates and insulin-dependent diabetics. Significant opsonophagocytosis (bactericidal index, greater than or equal to 90%) of five clinical isolates of type II GBS lacking components of protein antigen c was demonstrated by each of 12 adult sera, as well as by agammaglobulinemic serum, a result indicating that opsonophagocytosis can proceed by antibody-independent activation of the classic complement pathway. Strains containing components of protein antigen c were somewhat more resistant to opsonin-binding activity. Four of 10 neonatal sera and nine of 15 diabetic sera exhibited inefficient opsonophagocytosis. Some of the adult sera with either high or low concentrations of specific antibody to type II GBS promoted opsonophagocytosis via the alternative complement pathway, but this response was not observed with neonatal sera. The addition of sufficient amounts of specific antibody to type II GBS to neonatal and adult diabetic sera in vitro, however, promoted efficient opsonophagocytosis via the alternative pathway.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Proteínas del Sistema Complemento/inmunología , Proteínas Opsoninas/inmunología , Fagocitosis , Infecciones Estreptocócicas/inmunología , Adulto , Diabetes Mellitus/microbiología , Humanos , Recién Nacido , Streptococcus agalactiae
12.
Cell Immunol ; 159(2): 246-61, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7994757

RESUMEN

Human bone marrow transplantation is becoming more common in the treatment of certain forms of cancer despite the scarcity of HLA matched donors. Because human umbilical cord blood (HUCB) has been used as a source for stem cells in bone marrow transplantation, and because NK cells appear to be important in graft versus leukemia response, we investigated the lytic activity of freshly isolated HUCB NK cells (HUCB-NK) against tumor targets and their ability to differentiate into LAK cells following stimulation with various cytokines. Although cytotoxicity mediated by fresh HUCB-NK was low compared to that of adult peripheral blood lymphocyte-derived NK cells (PBL-NK), the ability of HUCB-NK to bind to K562 target cells (TC) was similar to PBL-NK. In addition, the PBL-NK cytotoxicity of postpartum mothers was also low compared to that of normal adult PBL-NK. When we incubated HUCB for 18 hr in either IL-2 or IL-12, we boosted the level of HUCB-NK cytotoxicity to approximately the level observed in PBL-NK and increased the level of perforin, granzyme A, and granzyme B mRNA expression. In addition, when we incubated HUCB in IL-2, IL-4, IL-7, IL-12, TNF-alpha, IFN-alpha, IFN-gamma, or TGF-beta for 5 days, we observed that HUCB was capable of generating LAK cells only when incubated with either IL-2 or IL-12. In contrast, IL-2, IL-7, IL-12, TNF-alpha, and IFN-gamma all generated LAK cells from adult PBL. When we added to the medium low-dose IL-2 and irradiated K562 as feeder cells (mini-LAK), we were unable to generate LAK activity from HUCB-NK, whereas we could generate it with PBL-NK cells under the same conditions. Addition of serum derived from HUCB in a 4-hr 51Cr release assay with PBL-NK as the effector cells (EC) and K562 as the TC resulted in a 42% decrease in PBL-NK-mediated cytotoxicity. Although we detected no TGF-beta in HUCB serum, we did detect high concentrations of soluble class I MHC (sHLA). To our knowledge, sHLA has not previously been shown to inhibit NK cytotoxicity, although the expression of class I HLA on the surface of TC has been shown to inhibit NK cytotoxicity. To study further the effect of sHLA on cell-mediated cytotoxicity, we added various concentrations of sHLA to EC mediating NK, ADCC, and CTL activities. All were inhibited in a dose-dependent manner.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Sangre Fetal/inmunología , Antígenos HLA/sangre , Células Asesinas Activadas por Linfocinas/inmunología , Células Asesinas Naturales/inmunología , Adulto , Northern Blotting , Adhesión Celular/inmunología , Línea Celular , Citocinas/inmunología , Pruebas Inmunológicas de Citotoxicidad , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Antígenos HLA/inmunología , Humanos , Procesamiento de Imagen Asistido por Computador , Recién Nacido , Pruebas de Precipitina
13.
Am J Obstet Gynecol ; 133(2): 171-3, 1979 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-369376

RESUMEN

This investigation was undertaken to determine the prevalence of group B streptococcal vaginal and throat colonization among lower socioeconomic pregnant women and the antibody concentration to the capsular polysaccharide antigen of type III group B streptococcus in their sera. Group B streptococci were recovered from 28.6 per cent of the 112 women studied; vaginal colonization was detected in 23.4 per cent, throat colonization in 4.7 per cent, and colonization at both sites in 0.9 per cent of the patients, respectively. Among these isolates of group B streptococci, serotypes III (39.5 per cent) and II (30.3 per cent) predominated. No differences were found between colonized and noncolonized women with respect to age, race, marital status, or parity. The majority of all women studied had low concentration of antibody in serum (less than 1.0 microgram per milliliter). However, women with isolation of type III group B streptococci from cultures at the time sera were collected had significantly higher concentrations than did women without group B streptococci from cultures at the time sera were collected had significantly higher concentrations than did women without group B streptococcal colonization.


Asunto(s)
Faringe/microbiología , Complicaciones Infecciosas del Embarazo/epidemiología , Infecciones Estreptocócicas/epidemiología , Vagina/microbiología , Adolescente , Adulto , Factores de Edad , Anticuerpos Antibacterianos/análisis , Portador Sano , Etnicidad , Composición Familiar , Femenino , Humanos , Paridad , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/transmisión , Factores Socioeconómicos , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/transmisión , Streptococcus agalactiae , Texas
14.
Am J Obstet Gynecol ; 137(1): 39-42, 1980 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-6989248

RESUMEN

An investigation of the prevalence and persistence of the concentration of antibody to capsular polysaccharide from type III, group B Streptococcus in sera from 93 pregnant women and their newborn infants is reported. In the majority of women, the concentrations of antibody detected in the sera were low (less than 1 microgram/ml). However, sera from women who were colonized with type III strains of group B streptococci contained significantly higher concentrations of antibody than those from noncolonized women (p = 0.027). No appreciable change in antibody concentration was found in sera collected early in gestation when compared to delivery sera. When maternal-cord serum pairs were analyzed, a significant correlation between concentrations of antibody was found, which indicates that this antibody is transplacentally transferred.


Asunto(s)
Anticuerpos Antibacterianos/análisis , Intercambio Materno-Fetal , Polisacáridos Bacterianos/inmunología , Streptococcus agalactiae/inmunología , Femenino , Sangre Fetal/análisis , Humanos , Inmunidad Materno-Adquirida , Recién Nacido , Enfermedades del Recién Nacido/inmunología , Embarazo , Infecciones Estreptocócicas/inmunología
15.
Infect Immun ; 35(3): 800-8, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6802760

RESUMEN

The relative roles of serum factors required for opsonization of type XIV Streptococcus pneumoniae were investigated by means of luminol-enhanced chemiluminescence (CL), bactericidal, and immunofluorescence assays employing adult sera containing high (>1,000 ng of antibody nitrogen per ml) or low (<200 ng of antibody nitrogen per ml) antibody concentrations as determined by radioimmunoassay. Specific antibody concentration correlated directly with both total and heat-labile CL activity (P < 0.005) and with the bactericidal index (P < 0.05) at a serum concentration of 10%. The importance of specific antibody as an opsonin was confirmed by the abolition of CL activity and immunoglobulin immunofluorescence observed after absorption of heated sera with type XIV pneumococcal cells and by the dose response in CL and bactericidal activity observed with the addition of immunoglobulin G to hypogammaglobulinemic serum. A role for the classical complement pathway in opsonization was indicated by significantly greater CL integrals for high-antibody sera than for low-antibody sera depleted of factor D and by the bactericidal activity noted for untreated, but not magnesium ethylene glycol-bis(beta-aminoethyl ether)-N,N-tetraacetic acid-chelated low-antibody sera. The alternative pathway contributed more than half of the CL activity of both high- and low-antibody sera. However, after magnesium ethylene glycol-bis(beta-aminoethyl ether)-N,N-tetraacetic acid chelation, only sera with high antibody concentrations or agammaglobulinemic serum reconstituted with immunoglobulin G with high specific antibody levels supported significant bactericidal activity. Therefore, type-specific antibody and complement promote opsonization of type XIV S. pneumoniae, and this may occur via either complement pathway. These results suggest that CL is a suitable tool to delineate serum factors and their contribution to opsonization, but results must be related to other functional assays.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Activación de Complemento , Proteínas Opsoninas/análisis , Fagocitosis , Streptococcus pneumoniae/inmunología , Actividad Bactericida de la Sangre , Relación Dosis-Respuesta Inmunológica , Ácido Egtácico/farmacología , Técnica del Anticuerpo Fluorescente , Humanos , Mediciones Luminiscentes
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