Vaccine Take of RV3-BB Rotavirus Vaccine Observed in Indonesian Infants Regardless of HBGA Status

BACKGROUND

Histo-blood group antigen (HBGA) status may affect vaccine efficacy due to rotavirus strains binding to HBGAs in a P genotype-dependent manner. This study aimed to determine if HBGA status affected vaccine take of the G3P[6] neonatal vaccine RV3-BB.

METHODS

DNA was extracted from stool samples collected in a subset (n = 164) of the RV3-BB phase IIb trial in Indonesian infants. FUT2 and FUT3 genes were amplified and sequenced, with any single-nucleotide polymorphisms analyzed to infer Lewis and secretor status. Measures of positive cumulative vaccine take were defined as serum immune response (immunoglobulin A or serum-neutralizing antibody) and/or stool excretion of RV3-BB virus. Participants were stratified by HBGA status and measures of vaccine take.

RESULTS

In 147 of 164 participants, Lewis and secretor phenotype were determined. Positive vaccine take was recorded for 144 (97.9%) of 147 participants with the combined phenotype determined. Cumulative vaccine take was not significantly associated with secretor status (relative risk, 1.00 [95% CI, .94-1.06]; P = .97) or Lewis phenotype (relative risk, 1.03 [95% CI, .94-1.14]; P = .33), nor was a difference observed when analyzed by each component of vaccine take.

CONCLUSIONS

The RV3-BB vaccine produced positive cumulative vaccine take, irrespective of HBGA status in Indonesian infants.

Histo-blood group antigen profile of Australian Aboriginal children and seropositivity following oral rotavirus vaccination

BACKGROUND

Histo-blood group antigens (HBGAs) may influence immune responses to rotavirus vaccination.

METHODS

HBGA phenotyping was determined by detection of antigens A, B, H and Lewis a and b in saliva using enzyme-linked immunosorbent assay. Secretor status was confirmed by lectin antigen assay if A, B and H antigens were negative or borderline (OD ± 0.1 of threshold of detection). PCR-RFLP analysis was used to identify the FUT2 'G428A' mutation in a subset. Rotavirus seropositivity was defined as serum anti-rotavirus IgA ≥ 20 AU/mL.

RESULTS

Of 156 children, 119 (76 %) were secretors, 129 (83 %) were Lewis antigen positive, and 105 (67 %) were rotavirus IgA seropositive. Eighty-seven of 119 (73 %) secretors were rotavirus seropositive, versus 4/9 (44 %) weak secretors and 13/27 (48 %) non-secretors.

CONCLUSIONS

Most Australian Aboriginal children were secretor and Lewis antigen positive. Non-secretor children were less likely to be seropositive to rotavirus antibodies following vaccination, but this phenotype was less common. HBGA status is unlikely to fully explain underperformance of rotavirus vaccines among Australian Aboriginal children.

Model-based estimation of the impact on rotavirus disease of RV3-BB vaccine administered in a neonatal or infant schedule

Rotavirus infection is a common cause of severe diarrheal disease and a major cause of deaths and hospitalizations among young children. Incidence of rotavirus has declined globally with increasing vaccine coverage. However, it remains a significant cause of morbidity and mortality in low-income countries where vaccine access is limited and efficacy is lower. The oral human neonatal vaccine RV3-BB can be safely administered earlier than other vaccines, and recent trials in Indonesia have demonstrated high efficacy. In this study, we use a stochastic individual-based model of rotavirus transmission and disease to estimate the anticipated population-level impact of RV3-BB following delivery according to either an infant (2, 4, 6 months) and neonatal (0, 2, 4 months) schedule. Using our model, which incorporated an age- and household-structured population and estimates of vaccine efficacy derived from trial data, we found both delivery schedules to be effective at reducing infection and disease. We estimated 95-96% reductions in infection and disease in children under 12 months of age when vaccine coverage is 85%. We also estimate high levels of indirect protection from vaccination, including 78% reductions in infection in adults over 17 years of age. Even for lower vaccine coverage of 55%, we estimate reductions of 84% in infection and disease in children under 12 months of age. While open questions remain about the drivers of observed lower efficacy in low-income settings, our model suggests RV3-BB could be effective at reducing infection and preventing disease in young infants at the population level.

The feasibility of SARS-CoV-2 surveillance using wastewater and environmental sampling in Indonesia

BACKGROUND

Wastewater-based epidemiology (WBE) surveillance as an early warning system (EWS) for monitoring community transmission of SARS-CoV-2 in low- and middle-income country (LMIC) settings, where diagnostic testing capacity is limited, needs further exploration. We explored the feasibility to conduct a WBE surveillance in Indonesia, one of the global epicenters of the COVID-19 pandemic in the middle of 2021, with the fourth largest population in the world where sewer and non-sewered sewage systems are implemented. The feasibility and resource capacity to collect samples on a weekly or fortnightly basis with grab and/or passive sampling methods, as well as to conduct qualitative and quantitative identification of SARS-CoV-2 ribonucleic acid (RNA) using real-time RT-PCR (RT-qPCR) testing of environmental samples were explored.

MATERIALS AND METHODS

We initiated a routine surveillance of wastewater and environmental sampling at three predetermined districts in Special Region of Yogyakarta Province. Water samples were collected from central and community wastewater treatment plants (WWTPs), including manholes flowing to the central WWTP, and additional soil samples were collected for the near source tracking (NST) locations (i.e., public spaces where people congregate).

RESULTS

We began collecting samples in the Delta wave of the COVID-19 pandemic in Indonesia in July 2021. From a 10-week period, 54% (296/544) of wastewater and environmental samples were positive for SARS-CoV-2 RNA. The sample positivity rate decreased in proportion with the reported incidence of COVID-19 clinical cases in the community. The highest positivity rate of 77% in week 1, was obtained for samples collected in July 2021 and decreased to 25% in week 10 by the end of September 2021.

CONCLUSION

A WBE surveillance system for SARS-CoV-2 in Indonesia is feasible to monitor the community burden of infections. Future studies testing the potential of WBE and EWS for signaling early outbreaks of SARS-CoV-2 transmissions in this setting are required.

Neonatal rotavirus vaccine (RV3-BB) immunogenicity and safety in a neonatal and infant administration schedule in Malawi: a randomised, double-blind, four-arm parallel group dose-ranging study

Background

Rotavirus vaccines reduce rotavirus-related deaths and hospitalisations but are less effective in high child mortality countries. The human RV3-BB neonatal G3P[6] rotavirus vaccine administered in a neonatal schedule was efficacious in reducing severe rotavirus gastroenteritis in Indonesia but had not yet been evaluated in African infants.

Methods

We did a phase 2, randomised, double-blind, parallel group dose-ranging study of three doses of oral RV3-BB rotavirus vaccine in infants in three primary health centres in Blantyre, Malawi. Healthy infants less than 6 days of age with a birthweight 2·5 to 4·0 kg were randomly assigned (1:1:1:1) into one of four treatment groups: neonatal vaccine group, which included high-titre (1·0 × 10⁷ focus-forming unit [FFU] per mL), mid-titre (3·0 × 10⁶ FFU per mL), or low-titre (1·0 × 10⁶ FFU per mL); and infant vaccine group, which included high-titre (1·0 × 10⁷ FFU per mL) using a computer generated code (block size of four), stratified by birth (singleton vs multiple). Neonates received their three doses at 0–5 days to 10 weeks and infants at 6–14 weeks. Investigators, participant families, and laboratory staff were masked to group allocation. Anti-rotavirus IgA seroconversion and vaccine take (IgA seroconversion and stool shedding) were evaluated. Safety was assessed in all participants who received at least one dose of vaccine or placebo. The primary outcome was the cumulative IgA seroconversion 4 weeks after three doses of RV3-BB in the neonatal schedule in the high-titre, mid-titre, and low-titre groups in the per protocol population, with its 95% CI. With the high-titre group as the active control group, we did a non-inferiority analysis of the proportion of participants with IgA seroconversion in the mid-titre and low-titre groups, using a non-inferiority margin of less than 20%. This trial is registered at ClinicalTrials.gov (NCT03483116).

Findings

Between Sept 17, 2018, and Jan 27, 2020, 711 participants recruited were randomly assigned into four treatment groups (neonatal schedule high titre n=178, mid titre n=179, low titre n=175, or infant schedule high titre n=179). In the neonatal schedule, cumulative IgA seroconversion 4 weeks after three doses of RV3-BB was observed in 79 (57%) of 139 participants in the high-titre group, 80 (57%) of 141 participants in the mid-titre group, and 57 (41%) of 138 participants in the low-titre group and at 18 weeks in 100 (72%) of 139 participants in the high-titre group, 96 (67%) of 143 participants in the mid-titre group, and 86 (62%) of 138 of participants in the low-titre. No difference in cumulative IgA seroconversion 4 weeks after three doses of RV3-BB was observed between high-titre and mid-titre groups in the neonatal schedule (difference in response rate 0·001 [95%CI −0·115 to 0·117]), fulfilling the criteria for non-inferiority. In the infant schedule group 82 (59%) of 139 participants had a cumulative IgA seroconversion 4 weeks after three doses of RV3-BB at 18 weeks. Cumulative vaccine take was detected in 483 (85%) of 565 participants at 18 weeks. Three doses of RV3-BB were well tolerated with no difference in adverse events among treatment groups: 67 (39%) of 170 participants had at least one adverse event in the high titre group, 68 (40%) of 172 participants had at least one adverse event in the mid titre group, and 69 (41%) of 169 participants had at least one adverse event in the low titre group.

Interpretation

RV3-BB was well tolerated and immunogenic when co-administered with Expanded Programme on Immunisation vaccines in a neonatal or infant schedule. A lower titre (mid-titre) vaccine generated similar IgA seroconversion to the high-titre vaccine presenting an opportunity to enhance manufacturing capacity and reduce costs. Neonatal administration of the RV3-BB vaccine has the potential to improve protection against rotavirus disease in children in a high-child mortality country in Africa.

Funding

Bill & Melinda Gates Foundation, Australian Tropical Medicine Commercialisation Grant.

Non-antibiotic medication use in an Indonesian community cohort 0-18 months of age

BACKGROUND

Rational medication use for treatment is mandatory, particularly in children as they are vulnerable to possible hazards of drugs. Understanding the medication use pattern is of importance to identify the problems of drug therapy and to improve the appropriate use of medication among this population.

METHODS

A post-hoc study of the RV3-BB Phase IIb trial to children aged 0-18 months which was conducted in Indonesia during January 2013 to July 2016. Any concomitant medication use and health events among 1621 trial participants during the 18 months of follow-up were documented. Information on medication use included the frequency, formulation, indication, duration of usage, number of regimens, medication types, and therapeutic classes.

RESULTS

The majority of participants (N = 1333/1621; 82.2%) used at least one non-antibiotic medication for treatment during the 18-month observation period. A total of 7586 medication uses were recorded, mostly in oral formulation (90.5%). Of all illnesses recorded, 24.7% were treated with a single drug regimen of non-antibiotic medication. The most common therapeutic classes used were analgesics/antipyretics (30.1%), antihistamines for systemic use (17.4%), cough and cold preparations (13.5%), vitamins (8.6%), and antidiarrheals (6.6%). The main medication types used were paracetamol (29.9%), chlorpheniramine (16.8%), guaifenesin (8.9%), zinc (4.6%), and ambroxol (4.1%). Respiratory system disorder was the most common reason for medication use (51.9%), followed by gastrointestinal disorders (19.2%), pyrexia (16.9%), and skin disorders (7.0%).

CONCLUSION

A large number of children were exposed to at least one medication during their early life, including those where evidence of efficacy and safety in a pediatric population is lacking. This supports the need for further research on pediatric drug therapy to improve the appropriate use of medication in this population.

Immunogenicity of four doses of oral poliovirus vaccine when co-administered with the human neonatal rotavirus vaccine (RV3-BB)

BACKGROUND

The RV3-BB human neonatal rotavirus vaccine was developed to provide protection from severe rotavirus disease from birth. The aim of this study was to investigate the potential for mutual interference in the immunogenicity of oral polio vaccine (OPV) and RV3-BB.

METHODS

A randomized, placebo-controlled trial involving 1649 participants was conducted from January 2013 to July 2016 in Central Java and Yogyakarta, Indonesia. Participants received three doses of oral RV3-BB, with the first dose given at 0-5 days (neonatal schedule) or ~8 weeks (infant schedule), or placebo. Two sub-studies assessed the immunogenicity of RV3-BB when co-administered with either trivalent OPV (OPV group, n = 282) or inactivated polio vaccine (IPV group, n = 333). Serum samples were tested for antibodies to poliovirus strains 1, 2 and 3 by neutralization assays following doses 1 and 4 of OPV.

RESULTS

Sero-protective rates to poliovirus type 1, 2 or 3 were similar (range 0.96-1.00) after four doses of OPV co-administered with RV3-BB compared with placebo. Serum IgA responses to RV3-BB were similar when co-administered with either OPV or IPV (difference in proportions OPV vs IPV: sIgA responses; neonatal schedule 0.01, 95% CI -0.12 to 0.14; p = 0.847; infant schedule -0.10, 95% CI -0.21 to -0.001; p = 0.046: sIgA GMT ratio: neonatal schedule 1.23, 95% CI 0.71-2.14, p = 0.463 or infant schedule 1.20, 95% CI 0.74-1.96, p = 0.448).

CONCLUSIONS

The co-administration of OPV with RV3-BB rotavirus vaccine in a birth dose strategy did not reduce the immunogenicity of either vaccine. These findings support the use of a neonatal RV3-BB vaccine where either OPV or IPV is used in the routine vaccination schedule.

Human Neonatal Rotavirus Vaccine (RV3-BB) to Target Rotavirus from Birth

BACKGROUND

A strategy of administering a neonatal rotavirus vaccine at birth to target early prevention of rotavirus gastroenteritis may address some of the barriers to global implementation of a rotavirus vaccine.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial in Indonesia to evaluate the efficacy of an oral human neonatal rotavirus vaccine (RV3-BB) in preventing rotavirus gastroenteritis. Healthy newborns received three doses of RV3-BB, administered according to a neonatal schedule (0 to 5 days, 8 weeks, and 14 weeks of age) or an infant schedule (8 weeks, 14 weeks, and 18 weeks of age), or placebo. The primary analysis was conducted in the per-protocol population, which included only participants who received all four doses of vaccine or placebo within the visit windows, with secondary analyses performed in the intention-to-treat population, which included all participants who underwent randomization.

RESULTS

Among the 1513 participants in the per-protocol population, severe rotavirus gastroenteritis occurred up to the age of 18 months in 5.6% of the participants in the placebo group (28 of 504 babies), in 1.4% in the neonatal-schedule vaccine group (7 of 498), and in 2.7% in the infant-schedule vaccine group (14 of 511). This resulted in a vaccine efficacy of 75% (95% confidence interval [CI], 44 to 91) in the neonatal-schedule group (P<0.001), 51% (95% CI, 7 to 76) in the infant-schedule group (P=0.03), and 63% (95% CI, 34 to 80) in the neonatal-schedule and infant-schedule groups combined (combined vaccine group) (P<0.001). Similar results were observed in the intention-to-treat analysis (1649 participants); the vaccine efficacy was 68% (95% CI, 35 to 86) in the neonatal-schedule group (P=0.001), 52% (95% CI, 11 to 76) in the infant-schedule group (P=0.02), and 60% (95% CI, 31 to 76) in the combined vaccine group (P<0.001). Vaccine response, as evidenced by serum immune response or shedding of RV3-BB in the stool, occurred in 78 of 83 participants (94%) in the neonatal-schedule group and in 83 of 84 participants (99%) in the infant-schedule group. The incidence of adverse events was similar across the groups. No episodes of intussusception occurred within the 21-day risk period after administration of any dose of vaccine or placebo, and one episode of intussusception occurred 114 days after the third dose of vaccine in the infant-schedule group.

CONCLUSIONS

RV3-BB was efficacious in preventing severe rotavirus gastroenteritis when administered according to a neonatal or an infant schedule in Indonesia. (Funded by the Bill and Melinda Gates Foundation and others; Australian New Zealand Clinical Trials Registry number, ACTRN12612001282875 .).

Interferon-gamma Therapy Activates Human Monocytes for Enhanced Phagocytosis ofMycobacterium aviumComplex in HIV-Infected Individuals

Defective immunological function of cells of the macrophage lineage contributes to the pathogenesis of HIV-1 infection. Because monocyte/macrophage function is enhanced by cytokines such as interferon-gamma (IFN-gamma), the use of this immunomodulator is of potential clinical interest as adjunctive immunotherapy in immunosuppressed individuals. In this study, we show that adjunctive IFN-gamma treatment in an HIV-infected individual with Mycobacterium avium complex (MAC) infection increased phagocytosis of MAC by blood monocytes when compared to cells from an HIV-infected patient who was receiving standard chemotherapy alone. Enhanced phagocytic efficiency resulting from IFN-gamma therapy was associated with increased surface expression of MHC II (HLA-DR), a phagocytic receptor (CD16), and the activation marker (CD69), although the levels of activation markers were dissimilar at baseline in the two participants. These results imply that IFN-gamma may be useful in restoring antimycobacterial function in immunosuppressed patients.

Non-immunogenicity of overlapping gag peptides pulsed on autologous cells after vaccination of HIV infected individuals

Background

HIV Gag-specific CD4+ and CD8+ T-cell responses are important for HIV immune control. Pulsing overlapping Gag peptides on autologous lymphocytes (OPAL) has proven immunogenic and effective in reducing viral loads in multiple pigtail macaque studies, warranting clinical evaluation.

Methodology

We performed a phase I, single centre, placebo-controlled, double-blinded and dose-escalating study to evaluate the safety and preliminary immunogenicity of a novel therapeutic vaccine approach ‘OPAL-HIV-Gag(c)’. This vaccine is comprised of 120 15mer peptides, overlapping by 11 amino acids, spanning the HIV Gag C clade sequence proteome, pulsed on white blood cells enriched from whole blood using a closed system, followed by intravenous reinfusion. Patients with undetectable HIV viral loads (<50 copies/ml plasma) on HAART received four administrations at week 0, 4, 8 and 12, and were followed up for 12 weeks post-treatment. Twenty-three people were enrolled in four groups: 12 mg (n = 6), 24 mg (n = 7), 48 mg (n = 2) or matching placebo (n = 8) with 18 immunologically evaluable. T-cell immunogenicity was assessed by IFNγ ELIspot and intracellular cytokine staining (ICS).

Results

The OPAL-HIV-Gag(c) peptides were antigenic in vitro in 17/17 subjects. After vaccination with OPAL-HIV-Gag(c), 1/6 subjects at 12 mg and 1/6 subjects at 24 mg dose groups had a 2- and 3-fold increase in ELIspot magnitudes from baseline, respectively, of Gag-specific CD8+ T-cells at week 14, compared to 0/6 subjects in the placebo group. No Gag-specific CD4+ T-cell responses or overall change in Rev, Nef, Tat and CMV specific responses were detected. Marked, transient and self-limiting lymphopenia was observed immediately post-vaccination (4 hours) in OPAL-HIV-Gag(c) but not in placebo recipients, with median fall from 1.72 to 0.67 million lymphocytes/mL for active groups (P<0.001), compared to post-placebo from 1.70 to 1.56 lymphocytes/ml (P = 0.16).

Conclusion/Significance

Despite strong immunogenicity observed in several Macaca nemestrina studies using this approach, OPAL-HIV-Gag(c) was not significantly immunogenic in humans and improved methods of generating high-frequency Gag-specific T-cell responses are required.

Name of Registry

ClinicalTrials.gov, Registry number: NCT01123915, URL trial registry database: http://www.clinicaltrials.gov/ct2/results?term=OPAL-HIV-1001&Search=Search

A randomised, placebo-controlled, first-in-human study of a novel clade C therapeutic peptide vaccine administered ex vivo to autologous white blood cells in HIV infected individuals

Background

Preclinical studies of overlapping 15mer peptides, spanning SIV, SHIV or HIV, pulsed on autologous PBMC ex vivo have demonstrated high level, virus-specific T cell responses and viral suppression in non-human primates (NHP). Opal-HIV-Gag(c) consists of 120 synthetic 15mer peptides spanning Clade C, consensus Gag, manufactured to current good manufacturing practice; having been evaluated in a good laboratory practice toxicology study in Macaca mulatta. We evaluated the safety and preliminary immunogenicity of such peptides administered intravenously after short-duration ex vivo incubation, to HIV-positive adults on suppressive antiretroviral therapy.

Methods and Findings

A first-in-human, placebo-controlled, double-blind, dose escalation study was conducted. Twenty-three patients with virus suppressed by antiretroviral therapy were enrolled in four groups 12 mg (n = 6), 24 mg (n = 6), 48 mg (n = 2) or matching placebo (n = 8). Treatment was administered intravenously after bedside enrichment of 120 mL whole blood for white cells using a closed system (Sepax S-100 device), with ex vivo peptide admixture (or diluent alone) and 37°C incubation for one hour prior to reinfusion. Patients received 4 administrations at monthly intervals followed by a 12-week observation post-treatment. Opal-HIV-Gag(c) was reasonably tolerated at doses of 12 and 24 mg. There was an increased incidence of temporally associated pyrexia, chills, and transient/self-limiting lymphopenia in Opal-HIV-Gag(c) recipients compared to placebo. The study was terminated early, after two patients were recruited to the 48 mg cohort; a serious adverse event of hypotension, tachycardia secondary to diarrhoea occurred following a single product administration. An infectious cause for the event could not be identified, leaving the possibility of immunologically mediated product reaction.

Conclusions

A serious, potentially life-threatening event of hypotension led to early, precautionary termination of the study. In the absence of a clearly defined mechanism or ability to predict such occurrence, further development of Opal-HIV-Gag(c) will not be undertaken in the current form.

Registration

ClinicalTrials.gov NCT01123915; EudraCT: 2008-005142-23

Antihypertensive efficacy of the angiotensin receptor blocker azilsartan medoxomil compared with the angiotensin-converting enzyme inhibitor ramipril

Drug therapy often fails to control hypertension. Azilsartan medoxomil (AZL-M) is a newly developed angiotensin II receptor blocker with high efficacy and good tolerability. This double-blind, controlled, randomised trial compared its antihypertensive efficacy and safety vs the angiotensin-converting enzyme inhibitor ramipril (RAM) in patients with clinic systolic blood pressure (SBP) 150-180 mm Hg. Patients were randomised (n=884) to 20 mg AZL-M or 2.5 mg RAM once daily for 2 weeks, then force-titrated to 40 or 80 mg AZL-M or 10 mg RAM for 22 weeks. The primary endpoint was change in trough, seated, clinic SBP. Mean patient age was 57±11 years, 52.4% were male, 99.5% were Caucasian. Mean baseline BP was 161.1±7.9/94.9±9.0 mm Hg. Clinic SBP decreased by 20.6±0.95 and 21.2±0.95 mm Hg with AZL-M 40 and 80 mg vs12.2±0.95 mm Hg with RAM (P<0.001 for both AZL-M doses). Adverse events leading to discontinuation were less frequent with AZL-M 40 and 80 mg (2.4% and 3.1%, respectively) than with RAM (4.8%). These data demonstrated that treatment of stage 1-2 hypertension with AZL-M was more effective than RAM and better tolerated.

A randomized, double-blind, dose-finding Phase II study to evaluate immunogenicity and safety of the third generation smallpox vaccine candidate IMVAMUNE

IMVAMUNE is a Modified Vaccinia Ankara (MVA)-based virus that is being developed as a safer 3rd generation smallpox vaccine. In order to determine the optimal dose for further development, a double-blind, randomized Phase II trial was performed testing three different doses of IMVAMUNE in 164 healthy volunteers. All three IMVAMUNE doses displayed a favourable safety profile, with local reactions as the most frequent observation. The 1 x 10(8)TCID(50) IMVAMUNE dose induced a total antibody response in 94% of the subjects following the first vaccination and the highest peak seroconversion rates by ELISA (100%) and PRNT (71%). This IMVAMUNE dose was considered to be optimal for the further clinical development of this highly attenuated poxvirus as a safer smallpox vaccine.

Safety and immunogenicity of IMVAMUNE, a promising candidate as a third generation smallpox vaccine

A Phase I trial was performed to investigate the safety and immunogenicity of the third generation smallpox vaccine MVA-BN (IMVAMUNE), a highly attenuated clone derived from the Modified Vaccinia Virus Ankara strain 571, in naive and pre-immunized subjects. A total of 86 healthy subjects received the vaccine in five groups using different doses and routes of administration. All 38 subjects seroconverted in the groups receiving the highest dose (10(8) TCID50). All vaccinations were well tolerated with mainly mild or moderate pain at the injection site being the most frequent symptom. The results indicate that MVA-BN has the potential to be developed as an efficient and safe alternative to the conventional smallpox vaccines such as Lister-Elstree or Dryvax. Unique attributes render it a promising candidate for prophylactic mass immunization, even in subjects for whom conventional smallpox vaccines are contraindicated.

Therapeutic Vaccination of HIV-1-Infected Patients on Haart with a Recombinant HIV-1 Nef-Expressing Mva: Safety, Immunogenicity and Influence on Viral Load during Treatment Interruption

The safety and immunogenicity of an HIV-1 nef-expressing modified vaccinia virus Ankara (MVA) was investigated in 14 HIV-1-positive patients (CD4 >400/μl) on highly active antiretroviral therapy (HAART). Patients were vaccinated at weeks 0, 4 and 16, followed by interruption of HAART at week 18. MVA- nef was well-tolerated except for local reactions, with only mild systemic side effects reported in a few patients. Vaccination with MVA- nef was associated with recognition of new HIV-1 T-cell epitopes (cytotoxic T-lymphocyte epitopes in 9/14 patients, CD4 epitope/recombinant Nef protein in 2/14) and an increase in CD4+ and CD8+ T cells. All patients had been vaccinated against smallpox and a strong T-cell and antibody response to MVA was induced in all patients. After interruption of HAART, viral load rebounded in all patients, but after a median time of 36 (4–76) weeks in 9/14 patients, viraemia remained below the pre-HAART viral load and CD4 counts stayed above the pre-HAART levels. While six patients have remained off therapy for a median time of 64 (57–76) weeks, HAART was resumed in 8/14 patients after a median treatment interruption time of 15 (4–38) weeks. This study has demonstrated that MVA- nef is safe and immunogenic in HIV-1-infected subjects and has provided encouraging data on the potential of therapeutic vaccinations.

Therapeutic vaccination of HIV-1-infected patients on HAART with a recombinant HIV-1 nef-expressing MVA: safety, immunogenicity and influence on viral load during treatment interruption

The safety and immunogenicity of an HIV-1 nef-expressing modified vaccinia virus Ankara (MVA) was investigated in 14 HIV-1-positive patients (CD4 >400/microl) on highly active antiretroviral therapy (HAART). Patients were vaccinated at weeks 0, 4 and 16, followed by interruption of HAART at week 18. MVA-nef was well-tolerated except for local reactions, with only mild systemic side effects reported in a few patients. Vaccination with MVA-nef was associated with recognition of new HIV-1 T-cell epitopes (cytotoxic T-lymphocyte epitopes in 9/14 patients, CD4 epitope/recombinant Nef protein in 2/14) and an increase in CD4+ and CD8+ T cells. All patients had been vaccinated against smallpox and a strong T-cell and antibody response to MVA was induced in all patients. After interruption of HAART, viral load rebounded in all patients, but after a median time of 36 (4-76) weeks in 9/14 patients, viraemia remained below the pre-HAART viral load and CD4 counts stayed above the pre-HAART levels. While six patients have remained off therapy for a median time of 64 (57-76) weeks, HAART was resumed in 8/14 patients after a median treatment interruption time of 15 (4-38) weeks. This study has demonstrated that MVA-nef is safe and immunogenic in HIV-1-infected subjects and has provided encouraging data on the potential of therapeutic vaccinations.

Association between a functional polymorphism in the serotonin transporter gene and diarrhoea predominant irritable bowel syndrome in women

BACKGROUND AND AIMS

Serotonin (5-hydroxtryptamine, 5-HT) is an important factor in gut function, playing key roles in intestinal peristalsis and secretion, and in sensory signalling in the brain-gut axis. Removal from its sites of action is mediated by a specific protein called the serotonin reuptake transporter (SERT or 5-HTT). Polymorphisms in the promoter region of the SERT gene have effects on transcriptional activity, resulting in altered 5-HT reuptake efficiency. It has been speculated that such functional polymorphisms may underlie disturbance in gut function in individuals suffering with disorders such as irritable bowel syndrome (IBS). The aim of this study was to assess the potential association between SERT polymorphisms and the diarrhoea predominant IBS (dIBS) phenotype.

SUBJECTS

A total of 194 North American Caucasian female dIBS patients and 448 female Caucasian controls were subjected to genotyping.

METHODS

Leucocyte DNA of all subjects was analysed by polymerase chain reaction based technologies for nine SERT polymorphisms, including the insertion/deletion polymorphism in the promoter (SERT-P) and the variable tandem repeat in intron 2. Statistical analysis was performed to assess association of any SERT polymorphism allele with the dIBS phenotype.

RESULTS

A strong genotypic association was observed between the SERT-P deletion/deletion genotype and the dIBS phenotype (p = 3.07x10(-5); n = 194). None of the other polymorphisms analysed was significantly associated with the presence of disease.

CONCLUSIONS

Significant association was observed between dIBS and the SERT-P deletion/deletion genotype, suggesting that the serotonin transporter is a potential candidate gene for dIBS in women.

Diversity of receptors binding HIV on dendritic cell subsets

The ability of HIV-1 to use dendritic cells (DCs) for transport and to transfer virus to activated T cells in the lymph node may be crucial in early HIV-1 pathogenesis. We have characterized primary DCs for the receptors involved in viral envelope attachment and observed that C-type lectin receptor (CLR) binding was predominant in skin DCs, whereas binding to emigrating and tonsil DCs was CD4-dependent. No one CLR was solely responsible for envelope binding on all skin DC subsets. DC-SIGN (DC-specific ICAM-3-grabbing nonintegrin) was only expressed by CD14(+)CDla(lo) dermal DCs. The mannose receptor was expressed by CD1a(hi) and CD14(+)CDla(lo) dermal DCs, and langerin was expressed by Langerhans cells. The diversity of CLRs able to bind HIV-1 in skin DCs may reflect their ability to bind a range of microbial glycoproteins.

Spectroscopic characterisation and identification of ecdysteroids using high-performance liquid chromatography combined with on-line UV--diode array, FT-infrared and 1H-nuclear magnetic resonance spectroscopy and time of flight mass spectrometry

A prototype multiply hyphenated reversed-phase HPLC system has been applied to the analysis of a mixture of pure ecdysteroids and an ecdysteroid-containing plant extract. Characterisation was achieved via a combination of diode array UV, 1H NMR, FT-IR spectroscopy and time of flight (TOF) mass spectrometry. This combination of spectrometers allowed the collection of UV, 1H NMR, IR and mass spectra for a mixture of pure standards enabling almost complete structural characterisation to be performed. The technique was then applied to a partially purified plant extract in which 20-hydroxyecdysone and polypodine B were identified despite incomplete chromatographic resolution and the presence of co-chromatographing interferents. The experimental difficulties in the use of such a systems for these analytes are described.

Reversed-phase high-performance liquid chromatography combined with on-line UV diode array, FT infrared, and 1H nuclear magnetic resonance spectroscopy and time-of-flight mass spectrometry: application to a mixture of nonsteroidal antiinflammatory drugs

A prototype multiply hyphenated system has been applied to the analysis of a mixture of nonsteroidal antiinflammatory drugs separated by reversed-phase HPLC. Characterization of the model NSAIDs was achieved via a combination of diode array UV, 1H NMR, FT-IR spectroscopy, and time-of-flight mass spectrometry. This combination of spectrometers allowed the collection of UV, 1H NMR, IR, and mass spectra together with atomic composition data enabling almost complete structural characterization to be performed.

Flow injection spectroscopic analysis of model drugs using on-line UV-diode array, FT-infrared and 1H-nuclear magnetic resonance spectroscopy and time-of-flight mass spectrometry

A prototype flow injection analysis (FIA) system for the characterisation of compounds via a combination of diode array UV, 1H NMR, FT-IR spectroscopy and time-of-flight (TOF) mass spectrometry has been investigated using a number of pharmaceuticals and related compounds as model compounds. This combination of spectrometers allowed the on-flow collection of UV, 1H NMR, IR and mass spectra together with atomic composition data, enabling almost complete structural characterisation to be performed. Practical detection limits with the current system were in the region of 50 micrograms, however, the use of state of the art spectrometers would result in a significant reduction in the amount of material required.

Size-exclusion chromatography with on-line ultraviolet, proton nuclear magnetic resonance and mass spectrometric detection and on-line collection for off-line Fourier transform infrared spectroscopy

The coupling of HPLC with UV detection and on-line NMR spectroscopy and mass spectrometry combined with a dedicated interface for the collection of the chromatographic eluent for subsequent Fourier transform (FT) IR has been investigated using a number of polymer additives as model compounds. Size-exclusion chromatography was performed using deuterated chloroform as eluent with the separation monitored on-line by UV detection at 254 nm and on-flow 1H-NMR and MS. The effluent from the NMR probe was directed to a dedicated HPLC interface where it was deposited on a germanium plate for subsequent FT-IR. NMR and MS spectra were successfully obtained for 2,6-di-tert.-butyl-4-methylphenol, octadecyl-3-(3,5-di-tert.-butyl-4-hydroxyphenyl) propionate (Irganox 1076) and diisooctyl phthalate on-line and FT-IR spectra for all three compounds were obtained off-line. Practical problems encountered with this multiple hyphenation are described.

Novel preconcentration technique for on-line coupling to high-speed narrow-bore capillary gas chromatography: sample enrichment by equilibrium (ab)sorption. II. Coupling to a portable micro gas chromatograph

The technique of equilibrium (ab)sorption has been proven to be a powerful method for preconcentration of gaseous samples for high-speed narrow-bore capillary gas chromatography (GC) in general and field-portable GC instruments, often referred as micro GCs, in particular. Using a simple experimental set-up equipped with an open-tubular enrichment column it is possible to produce a homogeneously enriched sample plug, allowing reproducible injections of an enriched sample into the micro GC. Using a non-polar trapping column enrichment factors found for n-alkanes in the range of C7 to C10 ranged from 15 to 150 and agree well with calculated values. Using a highly retentive Thermocap column, the enrichment factor observed for heptane was above 500. As the use of this new preconcentration method requires only minimum modification of the micro GC, the chromatographic performance of the instrument was not compromised by direct coupling to the preconcentration device. Examples of on-line enrichment with portable micro GC analysis of VOCs from air are shown. These examples clearly demonstrate the potentials of the new method in field analysis.