The development of cervical cancer and its precursors are linked to persistent infection with oncogenic types of human papillomavirus (HPV). Host immune responses seem to be determinants of risk for this disease. However, little is known about the immunologic determinants of HPV persistence. Here, we examined the association between lymphoproliferative responses to antigens/mitogens and persistent HPV infection in women older than 45 years. Women included in this study were participants in a 10,000-woman population-based cohort study of cervical neoplasia in Costa Rica. Women older than 45 years and HPV DNA positive at a screening visit were selected as cases (n = 283). We selected a comparably sized control group of HPV DNA-negative women, matched to cases on age and time since enrollment (n = 261). At an additional clinical visit, women were cytologically and virologically rescreened, and cervical and blood specimens were collected. Proliferative responses to phytohemagglutinin (PHA), influenza virus (Flu), and HPV16 virus-like particle (VLP) were lower among women with persistent HPV infection [median counts per minute (cpm): 72,849 for PHA, 1,241 for Flu, and 727 for VLP] than for the control group (median cpm: 107,049 for PHA, 2,111 for Flu, and 2,068 for VLP). The decreases were most profound in women with long-term persistence and were only observed for the oldest age group (z65 years). Our results indicate that an impairment in host immunologic responses is associated to persistent HPV infection. The fact that effects were evident for all studied stimuli is suggestive of a generalized effect.
Transient elastography (FibroScan) is a novel, rapid and noninvasive technique to assess liver fibrosis. Our objective was to compare transient elastography (TE) and other noninvasive serum indexes as alternatives to liver biopsy in HIV/hepatitis C virus (HCV)-coinfected patients. The fibrosis stage (METAVIR Score), TE, the aspartate aminotransferase-to-platelet ratio index, the Forns fibrosis index, FIB-4 and HGM-2 indexes were assessed in 100 patients between January 2007 and January 2008. The diagnostic values were compared by calculating the area under the receiver operating characteristic curves (AUROCs). Using TE, the AUROC (95% CI) of liver stiffness was 0.80 (0.72-0.89) when discriminating between F 2, 0.93 (0.85-1.00) when discriminating between F 3 and 0.99 (0.97-1.00) when discriminating between F or= 3, the AUROCs of TE were significantly higher than those obtained with the other four noninvasive indexes. Based on receiver operating characteristic curves, three cutoff values were chosen to identify F or= 3 (>or=11 kPa) and F4 (>or=14 kPa). Using these best cutoff scores, the negative predictive value and positive predictive value were 81.1% and 70.2% for the diagnosis of F or= 3 and 100% and 57.1% for the diagnosis of F4. Thus, Transient elastography accurately predicted liver fibrosis and outperformed other simple noninvasive indexes in HIV/HCV-coinfected patients. Our data suggest that TE is a helpful tool for guiding therapeutic decisions in clinical practice.
Unlike cutaneous HPV types, alpha mucosal HPV types were uncommon in the oral region and were predominately associated with sexual behavior. Clinical Trials Registration. NCT00128661.
HIV-infected patients aged ≥55 years have a high prevalence of frailty and a high burden of functional impairment. Optimal management of this population requires close collaboration between infectious diseases specialists and geriatricians.
Vibrio cholerae 638 is a living candidate cholera vaccine strain attenuated by deletion of the CTX⌽ prophage from C7258 (O1, El Tor Ogawa) and by insertion of the Clostridium thermocellum endoglucanase A gene into the hemagglutinin/protease coding sequence. This vaccine candidate was previously found to be well tolerated and immunogenic in volunteers. This article reports a randomized, double-blind, placebo-controlled trial conducted to test short-term protection conferred by 638 against subsequent V. cholerae infection and disease in volunteers in Cuba. A total of 45 subjects were enrolled and assigned to receive vaccine or placebo. The vaccine contained 10 9 CFU of freshly harvested 638 buffered with 1.3% NaHCO 3 , while the placebo was buffer alone. After vaccine but not after placebo intake, 96% of volunteers had at least a fourfold increase in vibriocidal antibody titers, and 50% showed a doubling of at least the lipopolysaccharide-specific immunoglobulin A titers in serum. At 1 month after vaccination, five volunteers from the vaccine group and five from the placebo group underwent an exploratory challenge study with 10 9 CFU of ⌬CTX⌽ attenuated mutant strain V. cholerae 81. Only two volunteers from the vaccine group shed strain 81 in their feces, but none of them experienced diarrhea; in the placebo group, all volunteers excreted the challenge strain, and three had reactogenic diarrhea. An additional 12 vaccinees and 9 placebo recipients underwent challenge with 7 ؋ 10 5 CFU of virulent strain V. cholerae 3008 freshly harvested from a brain heart infusion agar plate and buffered with 1.3% NaHCO 3 . Three volunteers (25%) from the vaccine group and all from the placebo group shed the challenge agent in their feces. None of the 12 vaccinees but 7 volunteers from the placebo group had diarrhea, and 2 of the latter exhibited severe cholera (>5,000 g of diarrheal stool). These results indicate that at 1 month after ingestion of a single oral dose (10 9 CFU) of strain 638, volunteers remained protected against cholera infection and disease provoked by the wild-type challenge agent V. cholerae 3008. We recommend that additional vaccine lots of 638 be prepared under good manufacturing practices for further evaluation.
Sera from Brucella abortus-infected and -vaccinated bovines recognized four lipopolysaccharide (LPS) determinants: two in the O-polysaccharide (A and C), one in the core oligosaccharide from rough Brucella LPS (R), and one in lipid A (LA). From 46 different hybridomas secreting monoclonal antibodies (MAbs) against various LPS moieties, 9 different specificities were identified. Two epitopes, A and C/Y, were present in the O-polysaccharide. Two epitopes were found in the core oligosaccharide (R1 and R2) of rough Brucella LPS. MAbs against R1 and R2 epitopes reacted against LPS from different rough Brucella species; however, MAbs directed to the R2 epitope also reacted against enterobacterial LPS from deep rough mutants. Three epitopes (LA1, LA2, and LA3) were located in the lipid A backbone. Different sets of MAbs recognized two epitopes in the lipid A-associated outer membrane protein (LAOmp3-1 and LAOmp3-2). LPS preparations from smooth brucellae had small amounts of rough-type LPS. Although LPS from rough brucellae did not show smooth-type LPS in western blots (immunoblots), two hybridomas generated from mice immunized with rough B. abortus produced antibodies against smooth B. abortus LPS. Results are discussed in relation to the structure and function of B. abortus LPS and to previous findings on the epitopic density of the molecule.
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