BACKGROUND: Vaccination is the best mode of protection against tick-borne encephalitis (TBE) and its sequelae. The duration of protection and the optimal interval of repeat booster doses are still debated. The current study evaluated the persistence of the antibody response 11-15 years after a first booster vaccination following different primary vaccination schedules with a TBE vaccine (Encepur Adults, manufactured by Bavarian Nordic, previously by GSK). METHODS: This phase IV, open-label, mono-centric extension study enrolled adults who had received (at ≥ 12 years of age) primary vaccination with one of three randomly assigned TBE vaccine schedules (rapid [group R], conventional [group C], or accelerated conventional schedule [group A]) followed by a booster dose 3 years later. The antibody response was measured annually from 11 to 15 years post-booster using a TBE virus neutralization test (NT). An NT titer of ≥ 10 was considered as a clinically meaningful threshold and surrogate for protection. RESULTS: In total, 194 participants were enrolled and included in the per-protocol set; 188 completed the study. The percentage of participants with an NT titer ≥ 10 was 100% in group R and 99.0% in group A at all visits and ranged from 100% (year 11) to 95.8% (year 15) in group C. NT geometric mean titers were similar in the three study groups (181-267 in group R, 142-227 in group C, 141-209 in group A). NT geometric mean titers also remained high among participants ≥ 50 years old (98-206) and ≥ 60 years old (91-191) across study groups and time points. CONCLUSIONS: This study showed neutralizing antibody persistence for at least 15 years after a first booster dose of the Encepur Adults TBE vaccine in all age groups evaluated, regardless of which primary vaccination schedule was given to adolescents or adults. Trialregistry: ClinicalTrials.gov: NCT03294135.

• Klíčová slova
• Antibody persistence, Booster vaccination, Immunization, Neutralizing antibodies, Primary vaccination, Tick-borne encephalitis,
• MeSH
• dospělí MeSH
• klíšťová encefalitida * prevence a kontrola   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• následné studie MeSH
• očkovací schéma MeSH
• předškolní dítě MeSH
• protilátky virové MeSH
• sekundární imunizace MeSH
• vakcinace MeSH
• virové vakcíny * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze IV MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• protilátky virové MeSH
• virové vakcíny * MeSH

BACKGROUND: Tick borne encephalitis (TBE) endemic zones are expanding. We previously evaluated long term persistence of antibody 5 years after the first booster immunization following different primary immunization schedules with the polygeline-free inactivated TBE vaccine (TBEvac) in adults and adolescents. Here, we report anti-TBE virus (TBEV) antibody persistence from 6 to 10 years post-booster administration. METHODS: This was a phase IV, open-label, single-center, second extension study (NCT01562444), conducted in Czechia. Healthy adults and adolescents ≥12 years who had received 3 different primary vaccination schedules (rapid, conventional and accelerated conventional) in the parent study and a booster dose before (12-18 months post-primary series completion) or at the beginning (3 years post-primary series completion) of the first extension study were screened and enrolled in this study. Blood samples were collected yearly and anti-TBEV antibody response was evaluated by neutralizing test (NT) antibody assays. Analysis was performed overall and per age strata: 15-49 years, ≥50 years, and ≥60 years. RESULTS: Of 206 screened individuals, 191 completed the study. Overall, 90-100% of participants in the all-screened set and ≥97% in the per-protocol set had the clinically meaningful threshold of protection (NT titers ≥10) across all timepoints, regardless of the primary vaccination schedule. Overall, antibody geometric mean titers (GMTs) varied from 134 to 343 in the all-screened set. Older age groups showed overall lower GMTs, although GMTs remained higher than NT titers ≥10 up to year 10 in all groups. CONCLUSION: This study showed long-term persistence of anti-TBEV NT antibodies for up to 10 years after the first booster dose of TBEvac in all age groups, regardless of the primary vaccination schedule.

• Klíčová slova
• Adults, Booster, Encepur, Long-term persistence, Tick-borne encephalitis,
• MeSH
• časové faktory MeSH
• dítě MeSH
• dospělí MeSH
• klíšťová encefalitida prevence a kontrola   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• následné studie MeSH
• neutralizující protilátky krev   MeSH
• očkovací schéma * MeSH
• protilátky virové krev   MeSH
• sekundární imunizace * MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• virové vakcíny aplikace a dávkování   imunologie   MeSH
• viry klíšťové encefalitidy imunologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze IV MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• neutralizující protilátky MeSH
• protilátky virové MeSH
• virové vakcíny MeSH

In tick-borne encephalitis (TBE)-endemic regions, long-term vaccination programs are efficient in preventing the disease. A booster dose of a polygeline-free inactivated TBE vaccine (Encepur Adults, GSK), administered approximately 3 years post-primary vaccination according to 1 of 3 licensed vaccination schedules in adults and adolescents, resulted in antibody persistence for 10 years post-boosting. We used different power-law models (PLMs) to predict long-term persistence of anti-TBE virus neutralization test (NT) antibody titers over a period of 20 years post-booster dose, based on individual antibody NT titers measured for 10 years post-booster vaccination. The PLMs were fitted on pooled data for all vaccine schedules. A mean NT titer of 261 (95% prediction interval: 22-3096), considerably above the accepted threshold of protection (NT titers ≥10), was predicted 20 years post-booster vaccination with TBE vaccine. Our modeled data suggest that the intervals of booster doses could be increased without compromising protection against TBE.

• Klíčová slova
• Tick-borne encephalitis, antibody persistence, polygeline-free inactivated TBE vaccine, power-law model, statistical model,
• MeSH
• dospělí MeSH
• klíšťová encefalitida * prevence a kontrola   MeSH
• lidé MeSH
• mladiství MeSH
• protilátky virové MeSH
• sekundární imunizace MeSH
• vakcinace MeSH
• virové vakcíny * MeSH
• viry klíšťové encefalitidy * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• protilátky virové MeSH
• virové vakcíny * MeSH

Long-term vaccination programs are recommended for individuals living in regions endemic for tick-borne encephalitis (TBE). Current recommendations suggest a first booster vaccine be administered 3 years after a conventional regimen or 12-18 months after a rapid regimen. However, the research supporting subsequent booster intervals is limited. The aim of this study was thus to evaluate the long-term persistence of TBE antibodies in adults and adolescents after a first booster dose with Encepur(®). A total of 323 subjects aged 15 years and over, who had received one of four different primary TBE vaccination series in a parent study, participated in this follow-up Phase IV trial. Immunogenicity and safety were assessed for up to five years after a first booster dose, which was administered three years after completion of the primary series. One subset of subjects was excluded from the booster vaccination since they had already received their booster prior to enrollment. For comparison, immune responses were still recorded for these subjects on Day 0 and on an annual basis until Year 5, but safety information was not collected. Following a booster vaccination, high antibody titers were recorded in all groups throughout the study. Neutralization test (NT) titers of ≥ 10 were noted in at least 94% of subjects at every time point post-booster (on Day 21 and through Years 1-5). These results demonstrated that a first booster vaccination following any primary immunization schedule results in high and long-lasting (>5 years) immune responses. These data lend support to the current belief that subsequent TBE booster intervals could be extended from the current recommendation. NCT00387634.

• Klíčová slova
• Booster immunization, Immunogenicity, Persistence, Tick-borne encephalitis,
• MeSH
• dospělí MeSH
• klíšťová encefalitida prevence a kontrola   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• následné studie MeSH
• neutralizační testy MeSH
• očkovací schéma MeSH
• protilátky virové krev   MeSH
• sekundární imunizace * MeSH
• virové vakcíny terapeutické užití   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze IV MeSH
• práce podpořená grantem MeSH
• Názvy látek
• Encepur MeSH Prohlížeč
• protilátky virové MeSH
• virové vakcíny MeSH

Persistence of immune response was assessed in adults aged >40 years (N = 596) following primary vaccination with combined hepatitis A/B vaccine or concomitant monovalent hepatitis A and B vaccines. Anti-hepatitis A virus antibody responses persisted for at least 4 years regardless of the vaccine used, with anti-hepatitis B surface antibody responses higher and more sustained in subjects who received the combined hepatitis A/B vaccine. Response rates to an additional dose of the same vaccine(s) used for priming were high.

• MeSH
• dospělí MeSH
• hepatitida A - protilátky krev   MeSH
• hepatitida A prevence a kontrola   MeSH
• hepatitida B - protilátky krev   MeSH
• hepatitida B prevence a kontrola   MeSH
• imunologická paměť * MeSH
• kombinované vakcíny imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• sekundární imunizace MeSH
• vakcína proti hepatitidě A aplikace a dávkování   imunologie   MeSH
• vakcína proti hepatitidě B aplikace a dávkování   imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• hepatitida A - protilátky MeSH
• hepatitida B - protilátky MeSH
• kombinované vakcíny MeSH
• vakcína proti hepatitidě A MeSH
• vakcína proti hepatitidě B MeSH

To assess the interval since the last revaccination against tetanus the persistence of antibodies was determined using ELISA test in 128 subject. Levels of antibodies against tetanus higher than the protective level of 0.1 IU/ml were found not only in those revaccinated less than ten years ago, but also in those revaccinated more than ten years before. With increasing length of the interval since last revaccination the antibody levels against tetanus decreased gradually although they remained above the protective level. No basic dependence of that trend on gender or age has been found. In the whole series, antibodies against tetanus exceeded the protective level for up to 20-25 years post last revaccination. This finding together with a favorable epidemiological situation as regards the occurrence of tetanus could eventually enable to prolong the interval for revaccinating adults in the Czech Republic.

• MeSH
• Clostridium tetani imunologie   MeSH
• dítě MeSH
• dospělí MeSH
• ELISA MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• protilátky bakteriální krev   MeSH
• sekundární imunizace MeSH
• tetanus prevence a kontrola   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• protilátky bakteriální MeSH

• Klíčová slova
• antibody persistence, neutralizing titer, power-law models, tick-borne encephalitis, vaccination,
• MeSH
• klíšťová encefalitida * prevence a kontrola   MeSH
• lidé MeSH
• sekundární imunizace MeSH
• vakcinace MeSH
• vakcíny * MeSH
• viry klíšťové encefalitidy * imunologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• dopisy MeSH
• komentáře MeSH
• práce podpořená grantem MeSH
• Názvy látek
• vakcíny * MeSH

We assessed the long-term persistence of humoral immunity against diphtheria in adults with childhood vaccination and the immunogenicity of a booster dose considering demographic, behavioural and vaccinating factors. We conducted a trial in 200 healthy Slovak adults aged 24-65 years, immunised against diphtheria in childhood and against tetanus at regular 10-15 year intervals, and receiving a dose of a tetanus-diphtheria toxoid vaccine. The response was determined by ELISA antibody concentrations of paired sera before and at 4 weeks post-vaccination. A seroprotection rate of 21% (95% confidence interval, CI 15.6-27.3%) was found in adults up to 59 years since the last vaccination with seroprotective levels of antibodies against diphtheria ≥0.1 IU/mL and a geometric mean concentration of 0.05 IU/mL. Conversely, seropositive levels ≥0.01 IU/mL were observed in 98% of adults (95% CI 95-99.5%). Booster-induced seroprotection was achieved in 78% of adults (95% CI 71.6-83.5%) clearly depending on pre-booster antibody levels correlating with age and time since the last vaccination. Moreover, only 54.2% of smokers and 53.3% of patients on statins exhibited seroprotection. Booster vaccination against diphtheria was unable to confer seroprotection in all recipients of only childhood vaccination.

• Klíčová slova
• diphtheria vaccination, immunity persistence, pre-vaccination levels, seroprotection rate, smoking, statins,
• Publikační typ
• časopisecké články MeSH

The persistence of maternal antibody against varicella-zoster virus was studied by the method of indirect haemagglutination (IH) and a control of the results was performed by radioimmunoassay (RIA). The findings were analysed with reference to the constant half-life of passively acquired IgG and the titre range and frequency of antibodies in 220 persons of fertile age representative of the normal population. Statistical analysis of expected and the experimentally obtained data was performed. Among the normal population, the expectancy is a gradual decrease in maternal IH antibody titres to negativity during the first 10 months of life and 100% sero-negativity by the 11th and 12th month. The experimental data showed a decrease in IH seropositivity from the initial 100% in 1-month infants to 27% in 6-month and 7% in 12-month infants. Nine out of twelve of the experimentally found positive titres in infants during the second half of their first year of life deviated from the normal population sample. The results obtained by both of the methods used were in good agreement.

• MeSH
• hemaglutinační testy MeSH
• imunita získaná od matky * MeSH
• imunoglobulin G analýza   MeSH
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• protilátky virové analýza   MeSH
• radioimunoanalýza MeSH
• virus varicella zoster imunologie   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobulin G MeSH
• protilátky virové MeSH

Preimmune antibody repertoire is not a statistical representation of all germ-line VH, D, JH and VL, JL segments encoding heavy and light chains, respectively. The antibody repertoire is biased towards a fraction of VH and VL gene segments in fetal/neonatal as well as adult life. The repertoire bias starts at the surface Ig-negative pre-B cells and persists throughout B-cell ontogeny. Antigen-independent processes like preferential rearrangements of VH, D and JH segments and pairing of the heavy and surrogate light chain operate at the surface Ig-negative pre-B cell stage. Subsequently B cells may be subject to self-antigen selection based on the specificity of their surface receptors.

• MeSH
• B-lymfocyty imunologie   MeSH
• dospělí MeSH
• geny pro imunoglobuliny * MeSH
• imunoglobuliny - fragmenty genetika   MeSH
• imunoglobuliny genetika   MeSH
• lidé MeSH
• modely imunologické MeSH
• novorozenec MeSH
• plod MeSH
• stárnutí imunologie   MeSH
• tvorba protilátek MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• novorozenec MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• imunoglobuliny - fragmenty MeSH
• imunoglobuliny MeSH