Antibody Response to BNT162b2 Vaccine in Immune Modifiers–Treated Psoriatic Patients

Background Data regarding anti–COVID-19 vaccination efficacy in psoriasis patients treated with immune-modulatory medications are scarce. Objective This study aims to examine the rate of positive antibody response following BNT162b2 vaccine in those patients. Methods BNT162b2-vaccinated and immune modifier–treated psoriatic patients were assigned to serological testing of IgG antibodies to protein S of SARS-CoV-2 after the second vaccination dose by Abbott Architect or Beckman Coulter. Levels ≥ 1 S1 units/mL (S/ml) and > 150 arbitrary units/ml (AU/ml) are considered a positive antibody response, respectively. The antibody levels further analyzed according to the patient’s characteristics and compared to health workers’ controls. Results Forty-nine of the 51 patients had a positive antibody response. Overall, patients treated with immune-modulatory medications had antibody levels similar to the control group. Conclusions Immune modifier–treated psoriasis patients seem to develop a positive antibody response to the full BNT162b2 vaccination in the vast majority of cases.

COVID-19 in Autoinflammatory Diseases with Immunosuppressive Treatment

COVID-19 disease increases interleukin (IL)-1β release. Anti-IL-1-treatment is effective in IL-1-mediated autoinflammatory diseases (AID). This case series presents COVID-19 in patients with IL-1-mediated and unclassified AID with immunosuppressive therapy (IT). Patient 1 is a 34-year-old woman with an unclassified AID and methotrexate. Patients 2 and 3 (14-year-old girl and 12-year-old boy, respectively) have a Cryopyrin-Associated Periodic Syndrome (NLRP3 p.Q703K heterozygous, CAPS) treated with canakinumab 150 mg/month since three and five years, respectively. Patient 4 is a 15-year-old girl who has had familial Mediterranean fever (MEFV p.M694V homozygous) for 3 years treated with canakinumab 150 mg/month and colchicine. All patients had a mild acute COVID-19 course, particularly the adolescent patients. A few weeks after COVID-19 recovery, both CAPS patients developed increased AID activity, necessitating anti-IL-1-treatment intensification in one patient. At day 100, one out of four patients (25%) showed positive antibody response to SARS-CoV-2. This is one of the first reports providing follow-up data about COVID-19 in AID. The risk for severe acute COVID-19 disease was mild/moderate, but increased AID activity post-COVID-19 was detected. Follow-up data and data combination are needed to expand understanding of COVID-19 and SARS-CoV-2 immunity in AID and the role of IT.

Prime-boost vaccination strategy enhances immunogenicity compared to single pneumococcal conjugate vaccination in patients receiving conventional DMARDs, to some extent in abatacept but not in rituximab-treated patients

Objective To explore whether a prime-boost vaccination strategy, i.e., a dose of pneumococcal conjugate vaccine (PCV) and a dose of 23-valent polysaccharide vaccine (PPV23), enhances antibody response compared to single PCV dose in patients with inflammatory rheumatic diseases treated with different immunosuppressive drugs and controls. Methods Patients receiving rituximab (n = 30), abatacept (n = 23), monotherapy with conventional disease-modifying antirheumatic drugs (cDMARDs, methotrexate/azathioprine/mycophenolate mofetil, n = 27), and controls (n = 28) were immunized with a dose PCV followed by PPV23 after ≥ 8 weeks. Specific antibodies to 12 serotypes included in both vaccines were determined using a multiplex microsphere immunoassay in blood samples before and 4–8 weeks after each vaccination. Positive antibody response was defined as ≥ 2-fold increase from pre- to postvaccination serotype-specific IgG concentration and putative protective level as IgG ≥ 1.3 μg/mL. The number of serotypes with positive antibody response and IgG ≥ 1.3 μg/mL, respectively, after PCV and PCV + PPV23 were compared within each treatment group and to controls. Opsonophagocytic activity (OPA) assay was performed for serotypes 6B and 23F. Results Compared to single-dose PCV, prime-boost vaccination increased the number of serotypes with positive antibody response in patients with abatacept, cDMARDs, and controls (p = 0.02, p = 0.01, and p = 0.01), but not in patients on rituximab. After PCV + PPV23, the number of serotypes with positive antibody response was significantly lower in all treatment groups compared to controls but lowest in rituximab, followed by the abatacept and cDMARD group (p < 0.001). Compared to PCV alone, the number of serotypes with putative protective levels after PCV + PPV23 increased significantly only in patients in cDMARDs (p = 0.03) and controls (p = 0.001). Rituximab treatment was associated with large reduction (coefficient − 8.6, p < 0.001) and abatacept or cDMARD with moderate reductions (coefficients − 1.9 and − 1.8, p = 0.005, and p < 0.001) in the number of serotypes with positive antibody response to PCV + PPV23 (multivariate linear regression model). OPA was reduced in rituximab (Pn6B and Pn23F, p < 0.001), abatacept (Pn23F, p = 0.02), and cDMARD groups (Pn6B, p = 0.02) compared to controls. Conclusions Prime-boost strategy enhances immunogenicity compared to single pneumococcal conjugate vaccination in patients with inflammatory rheumatic diseases receiving cDMARDs, to some extent in abatacept but not in patients on rituximab. Pneumococcal vaccination should be encouraged before the initiation of treatment with rituximab. Trial registration ClinicalTrials.gov, NCT03762824. Registered on 4 December 2018, retrospectively registered

PO 8597 NEUTRALISING AND NON-NEUTRALISING ANTIBODIES RESPONSE IN HIV-1-INFECTED INDIVIDUALS FROM MOZAMBIQUE

BackgroundA vaccine that protects against the different HIV subtypes circulating around the world is essential to control and eliminate HIV infection. The immunogens are the key to develop an effective HIV vaccine. In this study, we characterised the antibody response against recombinant C2V3C3 polypeptides from several HIV-1 subtypes and evaluated the neutralising antibody response.MethodsPlasmas from HIV-1-infected individuals under treatment (n=39) and drugs-naïve individuals (n=8) were tested in an ELISA assay to determine the presence of antibodies against polypeptides from HIV-1 subtypes (CRF02_AG, B, C, G and H). The neutralising activity of plasma was evaluated with a panel of six HIV-1 viruses from a reference panel, [one tier 1 (NL4.3), and five tier 2 (PCH119_CRF07, PCE1176_C, TRO11_B, 246 F3_AC and CRF07_BJOX2000)] in a TZM-bl cells-based assay.ResultsOut of 48 plasmas, 44 (89.6%) reacted at least with one polypeptide and four (10.4%) did not react with any polypeptide. Interestingly, 56% of the plasmas recognise ≥3 peptides and 6 reacted with all polypeptides. The polypeptide from virus CRF02_AG was the most antigenic (77%) followed by the polypeptide C (58.3%), G (58.3%), H (50%) and B (35.4%). There was a positive correlation between polypeptides number recognised and binding antibody reactivity (r=0.4895, p=0.0111). All plasmas from drugs-naïve individuals neutralised at least one virus with neutralising activity between 39.3% and 95.7%. Four plasmas showed neutralising activity >50% against five viruses. The virus 249 F3 was the easiest to neutralise (median, 65.7%), whereas PCH119_CRF07 was the most difficult to neutralise (median, 43.6%). Neutralising activity of plasmas from patients under treatment are ongoing.ConclusionIn summary, these polypeptides could be useful in vaccine design once they are very antigenic and we observed a heterologous neutralising antibody response in naïve patients that expressed positive antibody-response anti-peptides.

Community-wide outbreak ofEscherichia coliO157:H7 associated with consumption of frozen beef burgers

SUMMARYOn 24–25 October 2005 a cluster of five haemolytic uraemic syndrome (HUS) cases was reported in southwest France. An investigation was undertaken to identify the outbreak source and implement control measures. Cases were defined as individuals with HUS or diarrhoea with isolation ofEscherichia coliO157:H7 in stools or a positive antibody response toE. coliO157 lipopolysaccharide, resident in southwest France with symptom onset after 19 September 2005. Sixty-nine identified patients had symptom onset between 5 October and 3 November 2005, including 17 cases of HUS. One brand of frozen beef burgers produced on 22 August 2005 was consumed by all patients in the week before symptom onset.E. coliO157:H7 strains from patients, patients' burgers and the manufacturing plant were genetically related. This is the largest community-wide outbreak ofE. coliO157:H7 in France to date and the first associated with consumption of contaminated frozen beef burgers.

Pattern of acquisition of rotavirus antibody in children followed up from birth to the age of three years

Nine hundred and forty-eight serum samples from 83 children living in Belem, Brazil, collected'within their first three years of life, were testedfor the presence of group- specific rotavirus-antibody by an enzyme-linked immunosorbent assay (ELISA) blocking-test. Passively transferred maternal antibody lasted about two and half months; subsequentely, low levels of rotavirus antibody started to appear at seven months, reaching a peak at eleven months of age. From one year onwards positivity gradually increased, reaching highest values at 34 months of life. Individual responses were examined in sera from 61 children who were followed up since birth to three years of age: 38 (62,3%) ofthem developed a long-term immunity following first infection; eleven (18.0%) children developed a short-term immunity after first infection by rotavirus; seven (11.5%) had no antibody response within their first three years of life; and 5 (8.2%) showed positive antibody response from birth to three years old.

Induction of a cross-reactive idiotype dextran-positive antibody response in two IgH-Cb mouse strains treated with anti-J558 cross-reactive idiotype antibodies.

The effect of IdX-specific rabbit and allogeneic antiidiotype antibodies (Ab2) was investigated in vivo in Igh-Cb mouse strains with respect to the induction of a cross-reactive idiotype (IdX)-positive anti-alpha (1-3) Dextran (Dex) response. These C.B20 and C57Bl/6 mice have an allotype-linked incapacity to respond with IdX-positive anti-alpha (1-3) Dex antibodies upon conventional immunization with Dex B1355. 7 d after the rabbit Ab2 injections, IdX-positive Ig (Ab3) and IdX-positive anti-alpha (1-3) Dex antibodies (Ab1') were detected in the sera of each tested mouse. The affinity-purified Ab1' were idiotypically indistinguishable from reference BALB/c IdX-positive myeloma proteins and BALB/c anti-alpha (1-3) Dex antibodies (Ab1) in a competitive inhibition radioimmunoassay, while Ab3 Ig appeared idiotypically deficient and did not bind to Dex. The response to the alpha (1-6) linkage of Dex was not affected in these mice. A large fraction of the Ab1' and Ab3 responses of both mouse strains were of the IgG1 class. The Ab1' antibodies differed from BALB/c Ab1 by lower relative binding to five of eight tested Dex, and by expressing the Igh4b allotype determinants on the IgG1 antibodies. This study identifies the products of a VHDex gene that appears to be under regulatory control in the Ighb mice. Its association with the b haplotype suggests that this gene may differ structurally from the BALB/c VHDex gene.