C. Ferlito

Influenza vaccine administration in rheumatoid arthritis patients under treatment with TNFα blockers: Safety and immunogenicity

Twenty-eight patients with low-moderate, stable rheumatoid arthritis (RA), under treatment with tumor necrosis factor (TNF) alpha blockers, were immunized at least once with non-adjuvanted trivalent influenza vaccine during three consecutive influenza seasons. Antibodies toward A influenza antigens significantly increased and reached protective levels, still detectable 6 months after vaccination, both in RA patients and healthy controls. Response to B antigen instead was only observed from the second year for healthy controls and in the third year for patients. No significant difference in disease activity and anti-nuclear antibodies was observed as a consequence of vaccine administration, whereas T regulatory cells showed a significant increase 30 days after immunization in RA patients. This study confirms safety of influenza vaccine administration in RA patients treated with TNFalpha blockers. The cohort follow-up revealed the overcoming of poor B vaccine antigen immunogenicity via repeated vaccinations. Finally, protective antibody response was still observed 6 months after vaccination.

Imaging Progression despite Clinical Remission in Early Rheumatoid Arthritis Patients after Etanercept Interruption

The aim of this preliminary study is to evaluate clinical and imaging response in twenty patients with early Rheumatoid Arthritits (eRA) treated with Etanercept (Etn) + Methotrexate (Mtx) and to investigate whether clinical and MRI remission may be maintained after biological therapy interruption. Assessment included: radiography, Visser score and anti-CCP antibodies at baseline; disease activity score in 44 joints (DAS44), rheumatoid factor (RF), Magnetic Resonance Imaging (MRI) of hands and wrists at baseline (T0), 12 (T1), and 24 months (T2). MRI was scored for synovitis, bone oedema and erosions (OMERACT study); patients who reached clinical and imaging remission at T1 were considered eligible for interrupting Etn. At T1 8/20 (40%) patients showed a total remission [DAS44 from 5 (T0) to 1.4 (T1); p<0.02], whereas the other 12/20 (60%) showed an improvement, without complete remission [DAS44 from 4.8 (T0) to 2.8 (T1); p<0.05]. Etn was therefore interrupted in the first group of patients (group A), whereas it was continued in the other group (group B). At T2, group A maintained clinical remission and group B showed further not significant DAS44 reduction from T1. At T1, a significant reduction in synovitis, bone oedema and total score (p<0.01) was observed both in group A and in group B. At T2, group A showed an increase in all the MRI scores that was significant for the synovitis and total score, whereas group B exhibited a further not significant reduction. This preliminary study reports an excellent clinical and imaging response in eRA patients treated with Etn with total remission in 40% of them after a 1-year therapy period. However, it indicates that joint damage may progress, despite a sustained clinical remission, after Etn suspension

Lack of evidence for post-vaccine onset of autoimmune/lymphoproliferative disorders, during a nine-month follow-up in multiply vaccinated Italian military personnel

Anecdotal case reports, amplified by mass media and internet-based opinion groups, have recently indicated vaccinations as possibly responsible for autoimmunity/lymphoproliferation development. Multiply vaccinated Italian military personnel (group 1, operating in Italy, group 2, operating in Lebanon) were followed-up for nine months to monitor possible post-vaccine autoimmunity/lymphoproliferation onset. No serious adverse event was noticed in both groups. Multivariate analysis of intergroup differences only showed a significant association between lymphocyte increase and tetanus/diphtheria vaccine administration. A significant post-vaccine decrease in autoantibody positivity was observed. Autoantibodies were also studied by microarray analysis of self-proteins in subjects exposed to ≥4 concurrent vaccinations, without observing significant difference among baseline and one and nine months post-vaccine. Moreover, HLA-A2 subjects have been analyzed for the possible CD8T-cell response to apoptotic self-epitopes, without observing significant difference between baseline and one month post-vaccine. Multiple vaccinations in young adults are safe and not associated to autoimmunity/lymphoproliferation onset during a nine-month-long follow-up.

Tetanus-diphtheria vaccination in adults: the long-term persistence of antibodies is not dependent on polyclonal B-cell activation and the defective response to diphtheria toxoid re-vaccination is associated to HLADRB1∗01

Cellular and humoral immune responses to tetanus-diphtheria vaccine (Td) were assessed in human leukocyte antigen (HLA)-typed Italian military personnel who received multiple concomitant vaccines. Td-specific antibodies and T-lymphocytes were measured in individuals with one (group-1) and more than one (group-2) Td boosters. A third group (group-3), who received several vaccines, but not Td, was studied to verify the hypothesis of the polyclonal B-cell activation as mechanism for antibody persistence. The antibody response to Td toxoids was higher in group-1, who showed lower baseline antibody levels, than in group-2 subjects. The antibody response to tetanus was higher than to diphtheria toxoid in both groups. No correlation between antibody and cellular response, and no interference in the response to Td by co-administration of different vaccines were observed. HLA-DRB1∗01 allele was detected at significant higher frequency in subjects unable to double the baseline anti-diphtheria antibody levels after the vaccination. Anti-tetanus and diphtheria antibodies half-lives were assessed and the long-lasting persistence above the threshold for protection (0.1 IU/ml) was estimated in over 65 and 20 years, respectively. No significant increase of anti-diphtheria antibodies was observed in consequence of polyclonal B-cell activation. This study emphasizes the duration of Td vaccination-induced seroprotection, suggesting that re-vaccination should probably be performed at intervals longer than 10 years. No reciprocal interference by concomitantly administered vaccines has been observed. HLA-DRB1∗01 allele was significantly associated with anti-diphtheria defective response. Finally, this study does not confirm that anti-diphtheria antibody levels are maintained by polyclonal B-cell activation. Clinical trial registry: The study was registered with NCT01807780.

Immunogenicity of meningococcal polysaccharide ACWY vaccine in primary immunized or revaccinated adults: Meningococcal Polysaccharide Re-Vaccination

Meningococcal polysaccharide (Men‐Ps) vaccine immunogenicity following either primary immunization or revaccination in adults was evaluated. The study population consisted of subjects who have received tetravalent Men‐Ps vaccine once (group 1) or at least twice, with a 2–6 dose range (group 2). Human leucocyte antigen (HLA)‐typing was performed by polymerase chain reaction and specific immunoglobulin (Ig)G was measured by enzyme‐linked immunosorbent assay. Nine months post‐immunization, the percentages of individuals with levels of anti‐Men‐Ps IgG ≥ 2 µg/ml were comparable in both groups, with the exception of anti‐Men‐PsW135 IgG, which were significantly higher in group 2. The percentage of subjects doubling IgG levels at 9 months was significantly higher in group 1. The high baseline anti‐Men‐Ps antibody levels negatively influenced the response to revaccination, suggesting a feedback control of specific IgG. The calculated durability of anti‐Men‐Ps IgG was 2·5–4·5 years, depending on the Men‐Ps, following a single vaccine dose. No interference by other vaccinations nor HLA alleles association with immune response were observed. This study confirms that Men‐Ps vaccine in adults is immunogenic, even when administered repeatedly, and underlines the vaccine suitability for large‐scale adult immunization programmes that the higher costs of conjugate vaccines may limit in developing countries.

Anti-polysaccharide and anti-diphtheria protective antibodies after 13-valent pneumococcal conjugate vaccination in rheumatoid arthritis patients under immunosuppressive therapy

Immunogenicity of 13-valent pneumococcal polysaccharide (PnPS) conjugate vaccine (PCV13) was evaluated in 38 rheumatoid arthritis patients under immunosuppressive treatment and 20 healthy controls (HC). Antibodies to all PnPS and diphtheria-toxin analogue conjugate protein were measured pre- (T0), 1 (T1), 6 (T2), 12 (T3) months post-immunization. Patients and HC had similar response to individual PnPS. Mean antibody levels to all PnPS but one doubled at T1 compared with T0, with T3 persistence for only 8-7/13 PnPS. Baseline antibody levels was inversely associated with the rate of responders at T1 (T1/T0≥2) to 11/13 PnPS. Few subjects reached protective IgG levels against some serotypes frequently isolated in Italian patients with invasive pneumococcal disease. Antibody response was not influenced by therapy, except the one to PS7F, which was reduced by tumor necrosis factor-α-inhibitors. Vaccination increased also anti-diphtheria IgG. Despite this study substantially confirmed the PCV13 immunogenicity in immunocompromised patients, it also revealed some limitations.