12 research outputs found
Clinical and humoral response after SARS-CoV-2 breakthrough infection in patients receiving immunosuppressant therapy
Background: Despite impaired humoral response in patients treated with immunosuppressants (ISPs), recent studies found similar severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection compared to controls. One potential explanation is the rapid generation of humoral response on infection, but evidence is lacking. Objectives: We investigated the longitudinal dynamics of the SARS-CoV-2 antibody repertoire after SARS-CoV-2 delta and omicron breakthrough infection in patients with immune-mediated inflammatory diseases (IMIDs) receiving ISP therapy and controls. Methods: As a prospective substudy of the national Target-to-B! (T2B!) consortium, we included IMID patients receiving ISPs therapy and controls who reported SARS-CoV-2 breakthrough infection between July 1, 2021, and April 1, 2022. To get an impression of the dynamics of the antibody repertoire, 3 antibody titers of wild-type RBD, wild-type S, and omicron RBD were measured at 4 time points after SARS-CoV-2 breakthrough infection. Results: We included 302 IMID patients receiving ISPs and 178 controls. Antibody titers increased up to 28 days after breakthrough infection in both groups. However, in IMID patients receiving therapy with anti-CD20 and sphingosine-1 phosphate receptor modulators, antibody titers were considerably lower compared to controls. In the anti-TNF group, we observed slightly lower antibody titers in the early stages and a faster decline of antibodies after infection compared to controls. Breakthrough infections were mostly mild, and hospitalization was required in less than 1% of cases. Conclusions: Most ISPs do not influence the dynamics of the SARS-CoV-2 antibody repertoire and exhibit a rapid recall response with cross-reactive antibody clones toward new virus variants. However, in patients treated with anti-CD20 therapy or sphingosine-1 phosphate receptor modulators, the dynamics were greatly impaired, and to a lesser extent in those who received anti-TNF. Nevertheless, only a few severe breakthrough cases were reported.</p
Sexual selection and sympatric speciation
Het ontstaan van nieuwe biologische soorten stelt evolutiebiologen nog steeds voor een raadsel. Lang dacht men dat soortvorming een ruimtelijke scheiding tussen populaties vereist, als barrière tegen de uitwisseling van erfelijk materiaal door geslachtelijke voortplanting. Inmiddels zijn er aanwijzingen dat soortvorming ook kan optreden bĂnnen een leefgebied, zonder ruimtelijke scheiding. De opmerkelijke soortenrijkdom aan cichliden in bepaalde Afrikaanse kratermeertjes is waarschijnlijk op die manier ontstaan. In samenhang met het verschil in het belang dat wordt toegekend aan ruimtelijke scheiding, lopen de verschillende visies op soortvorming ook sterk uiteen als het gaat om de drijvende kracht achter het soortvormingsproces. Is dat natuurlijke selectie, of zijn het toevallige en onvoorspelbare gebeurtenissen in het milieu? Het antwoord op deze vraag bepaalt in belangrijke mate in hoeverre evolutie verloopt als een voorspelbaar en deterministisch proces.
Sander van Doorn richtte zijn promotieonderzoek op de rol van seksuele selectie bij soortvorming. Seksuele selectie is dat deel van natuurlijke selectie dat specifiek samenhangt met de competitie om partners voor seksuele voortplanting. Het is bekend dat seksuele selectie kan leiden tot de evolutie van sterke paringsvoorkeuren bij vrouwtjes en daarop aangepaste secundaire geslachtskenmerken bij mannetjes. Met de extravagante staart van de pauw en de rode buik van de stekelbaars als fraai gevolg. Dit proces zou kunnen leiden tot soortvorming als er tegelijkertijd uiteenlopende paringsvoorkeuren ontstaan binnen Ă©Ă©n populatie. Van Doorn komt met zijn wiskundige modellen echter tot de conclusie dat een dergelijke divergentie van paringsvoorkeuren onmogelijk is onder de standaard aannames van seksuele selectiemodellen. Soortvorming door seksuele selectie blijkt specifieke biologische omstandigheden te vereisen, die veel restrictiever zijn dan voorheen werd gesteld. Dit suggereert dat soortvorming slechts onder specifieke voorwaarden begrepen kan worden als een voorspelbare uitkomst van selectie, en dus in veel gevallen afhankelijk zal zijn van toevallige veranderingen in het milieu. /FC
Humoral responses after second and third SARS-CoV-2 vaccination in patients with immune-mediated inflammatory disorders on immunosuppressants: a cohort study
Background: Disease-specific studies have reported impaired humoral responses after SARS-CoV-2 vaccination in patients with immune-mediated inflammatory disorders treated with specific immunosuppressants. Disease-overarching studies, and data on recall responses and third vaccinations are scarce. Our primary objective was to investigate the effects of immunosuppressive monotherapies on the humoral immune response after SARS-CoV-2 vaccination in patients with prevalent immune-mediated inflammatory disorders. Methods: We did a cohort study in participants treated in outpatient clinics in seven university hospitals and one rheumatology treatment centre in the Netherlands as well as participants included in two national cohort studies on COVID-19-related disease severity. We included patients aged older than 18 years, diagnosed with any of the prespecified immune-mediated inflammatory disorders, who were able to understand and complete questionnaires in Dutch. Participants with immune-mediated inflammatory disorders who were not on systemic immunosuppressants and healthy participants were included as controls. Anti-receptor binding domain IgG responses and neutralisation capacity were monitored following standard vaccination regimens and a three-vaccination regimen in subgroups. Hybrid immune responses—ie, vaccination after previous SARS-CoV-2 infection—were studied as a proxy for recall responses. Findings: Between Feb 2 and Aug 1, 2021, we included 3222 participants in our cohort. Sera from 2339 participants, 1869 without and 470 participants with previous SARS-CoV-2 infection were analysed (mean age 49·9 years [SD 13·7]; 1470 [62·8%] females and 869 [37·2%] males). Humoral responses did not differ between disorders. Anti-CD20 therapy, sphingosine 1-phosphate receptor (S1P) modulators, and mycophenolate mofetil combined with corticosteroids were associated with lower relative risks for reaching seroconversion following standard vaccination (0·32 [95% CI 0·19–0·49] for anti-CD20 therapy, 0·35 [0·21–0·55] for S1P modulators, and 0·61 [0·40–0·90] for mycophenolate mofetil combined with corticosteroids). A third vaccination increased seroconversion for mycophenolate mofetil combination treatments (from 52·6% after the second vaccination to 89·5% after the third) but not significantly for anti-CD20 therapies (from 36·8% to 45·6%) and S1P modulators (from 35·5% to 48·4%). Most other immunosuppressant groups showed moderately reduced antibody titres after standard vaccination that did not increase after a third vaccination, although seroconversion rates and neutralisation capacity were unaffected. In participants with previous SARS-CoV-2 infection, SARS-CoV-2 antibodies were boosted after vaccination, regardless of immunosuppressive treatment. Interpretation: Humoral responses following vaccination are impaired by specific immunosuppressants. After standard vaccination regimens, patients with immune-mediated inflammatory disorders taking most immunosuppressants show similar seroconversion to controls, although antibody titres might be moderately reduced. As neutralisation capacity and recall responses are also preserved in these patients, this is not likely to translate to loss of (short-term) protection. In patients on immunosuppressants showing poor humoral responses after standard vaccination regimens, a third vaccination resulted in additional seroconversion in patients taking mycophenolate mofetil combination treatments, whereas the effect of a third vaccination in patients on anti-CD20 therapy and S1P modulators was limited. Funding: ZonMw (The Netherlands Organization for Health Research and Development)
Disease activity in patients with immune-mediated inflammatory diseases after SARS-CoV-2 vaccinations.
For patients with immune-mediated inflammatory diseases (IMIDs), concerns exist about increased disease activity after vaccination. We aimed to assess changes in disease activity after SARS-CoV-2 vaccination in patients with IMIDs, and determine risk factors for increased disease activity. In this substudy of a prospective observational cohort study (Target-to-B!), we included patients with IMIDs who received a SARS-CoV-2 vaccine. Patients reported changes in disease activity on a five-point Likert scale every 60 days for up to twelve months after first vaccination. In case of self-reported increased activity, hospital records were screened whether the treating physician reported increased activity, and for potential intensification of immunosuppressive (ISP) treatment. Mixed models were used to study determinants for self-reported increased disease activity. In total, 2111 patients were included for analysis after primary immunization (mean age 49.7 years [SD 13.7], 1329/2111 (63.0%) female), from which 1266 patients for analysis after first additional vaccination. Increased disease activity at 60 days after start of primary immunization was reported by 223/2111 (10.6%). In 96/223 (43.0%) the increase was confirmed by the treating physician and in 36/223 (16.1%) ISP treatment was intensified. Increased disease activity at seven to 60 days after additional vaccination, was reported by 139/1266 (11.0%). Vaccinations were not temporally associated with self-reported increased disease activity. Conversely, increased disease activity before first vaccination, neuromuscular disease, and multiple sclerosis were associated. Altogether, self-reported increased disease activity after vaccination against SARS-CoV-2 was recorded in a minority of patients and was generally mild. Moreover, multivariate analyses suggest that disease related factors, but not vaccinations are the major determinants for self-reported increased disease activity