Project description:BackgroundDetermining the humoral immunogenicity of tozinameran (BNT162b2) in patients requiring chronic renal replacement therapy, and its impact on COVID-19 morbidity several months after vaccination, may guide risk assessment and changes in vaccination policy.MethodsIn a prospective post-vaccination cohort study with up to 5 months follow-up we studied outpatient dialysis and kidney transplant patients and respective healthcare teams. Outcomes were anti S1/S2 antibody responses to vaccine or infection, and infection rate during follow-up.ResultsOne hundred seventy-five dialysis patients (40% women, 65 ± 15 years), 252 kidney transplant patients (33% women, 54 ± 14 years) and 71 controls (65% women, 44 ± 14 years) were followed. Three months or longer after vaccination we detected anti S1/S2 IgG antibodies in 79% of dialysis patients, 42% of transplant recipients and 100% of controls, whereas respective rates after infection were 94%, 69% and 100%. Predictors of non-response were older age, diabetes, history of cancer, lower lymphocyte count and lower vitamin-D levels. Factors associated with lower antibody levels in dialysis patients were modality (hemodialysis vs peritoneal) and high serum ferritin levels. In transplant patients, hypertension and higher calcineurin or mTOR inhibitor drug levels were linked with lower antibody response. Vaccination was associated with fewer subsequent infections (HR 0.23, p < 0.05). Moreover, higher antibody levels (particularly above 59 AU/ml) were associated with fewer events, with a HR 0.41 for each unit increased in log10titer (p < 0.05).ConclusionsDialysis patients, and more strikingly kidney transplant recipients, mounted reduced antibody response to COVID-19 mRNA vaccination. Lesser humoral response was associated with more infections. Measures to identify and protect non-responsive patients are required.
Project description:As solid organ transplant (SOT) recipients remain at risk of severe outcomes after SARS-CoV-2 infections, vaccination continues to be an important preventive measure. In SOT recipients previously vaccinated with at least three doses of BNT162b2, we investigated humoral responses to BNT162b2 booster doses. Anti-SARS-CoV-2 receptor binding domain (RBD) immunoglobulin G (IgG) was measured using an in-house ELISA. Linear mixed models were fitted to investigate the change in the geometric mean concentration (GMC) of anti-SARS-CoV-2 RBD IgG after vaccination in participants with intervals of more or less than six months between the last two doses of vaccine. We included 107 SOT recipients vaccinated with a BNT162b2 vaccine. In participants with an interval of more than six months between the last two vaccine doses, we found a 1.34-fold change in GMC per month (95% CI 1.25-1.44), while we found a 1.09-fold change in GMC per month (95% CI 0.89-1.34) in participants with an interval of less than six months between the last two vaccine doses, resulting in a rate ratio of 0.82 (95% CI 0.66 to 1.01, p = 0.063). In conclusion, the administration of identical COVID-19 mRNA vaccine boosters within six months to SOT recipients may result in limited humoral immunogenicity of the last dose.
Project description:Novel mRNA-based vaccines have been proven to be powerful tools in combating the global pandemic caused by SARS-CoV-2, with BNT162b2 (trade name: Comirnaty) efficiently protecting individuals from COVID-19 across a broad age range. Still, it remains largely unknown how renal insufficiency and immunosuppressive medication affect development of vaccine-induced immunity. We therefore comprehensively analyzed humoral and cellular responses in kidney transplant recipients after the standard second vaccination dose. As opposed to all healthy vaccinees and the majority of hemodialysis patients, only 4 of 39 and 1 of 39 transplanted individuals showed IgA and IgG seroconversion at day 8 ± 1 after booster immunization, with minor changes until day 23 ± 5, respectively. Although most transplanted patients mounted spike-specific T helper cell responses, frequencies were significantly reduced compared with those in controls and dialysis patients and this was accompanied by a broad impairment in effector cytokine production, memory differentiation, and activation-related signatures. Spike-specific CD8+ T cell responses were less abundant than their CD4+ counterparts in healthy controls and hemodialysis patients and almost undetectable in transplant patients. Promotion of anti-HLA antibodies or acute rejection was not detected after vaccination. In summary, our data strongly suggest revised vaccination approaches in immunosuppressed patients, including individual immune monitoring for protection of this vulnerable group at risk of developing severe COVID-19.
Project description:Abstract BACKGROUND AND AIMS Mortality due to SARS-COV-2 infection in hemodialysis (HD) patients and kidney transplant recipients(KTRs) is high. Despite increased rates of administration of two doses of mRNA vaccines among these vulnerable populations, the adequacy of the respective generated immune responses is reported lower than general population, especially in KTRs. A third booster dose has been officially recommended in these immunocompromised patients while the humoral and cellular immune responses to SARS-COV-2 vaccination remains to be elucidated in HD patients and KTRs. The aim of our study was to investigate the antibody (Ab) response status together with vaccine-induced alterations in circulating lymphocytes subsets, following the administration of three doses of the BNT162b2 vaccine in a cohort of maintenance HD patients and KTRs. METHOD The initial cohort of this prospective study (ClinicalTrials.gov, NCT04932876) included 34 HD patients and 54 KTRs who received two doses of the BNT162b2 (Pfizer–BioNTech). Of this cohort, 24 HD patients and 30 KTRs, who remained free of SARS-CoV2 infection and receive a third dose 6 months after the second dose, were finally analyzed. Lymphocyte subpopulations, including B cells, CD4+and CD8+T cells as well as naïve and memory T lymphocytes subpopulations among others, were analyzed by flow cytometry at four time points, before vaccination (T0), before the second dose (T1), 2 weeks after the second dose (T2) and 2–3 weeks after the third dose (T3). The anti-SARS-CoV2 antibody (Ab) response was assessed by using the ARCHITECT IgG II Quant test (Abbott). Titers >50 arbitrary units (AU)/mL were considered positive for seroconversion at T1 and at T2 and T3. RESULTS Of the initial cohort 31 HD patients (91.8%) and 16 KTRs (29.6%) became seropositive at T2. Of the final cohort (24 HD and 30 KTRs), almost all HD patients (23, 96%) became seropositive since T2 and this finding remained at T3 (Figure 1). In KTRs the percentage of responders was doubled between T2 and T3, T2 9 KTRs (30%) versus T3 18 KTRs (60%) (Figure 1). KTRs who developed Ab at T1 ``respond'' better to the third dose, maximizing the levels of Ab. HD patients who became seropositive at T1 displayed higher CD19+B lymphocytes compared with their seronegative HD counterparts. In HD patients, a positive correlation was established between CD19+B cells counts and Ab titers at all time-points (P < 0.001). In KTRs, Ab at T1 showed an inverse correlation with T+B+NK at T1 (P = 0.006). T2-Ab showed inverse correlation with CD45RA+CD45RO at T0 (P = 0.01) and with CD3+at T3 (P = 0.02). T3-Ab showed positive correlation with CD3+CD16+56+at T2 (P = 0.003) and with CD3-CD16+56+at T3 (P = 0.01). CD19+at T3 correlated positively with Ab at T1 and T3 (P = 0.003 and P = 0.03, respectively). CONCLUSION Our study confirms the improved immunogenicity after the third dose of BNT162b2 vaccine in KTRs. The positive correlation between CD19+B cells and Ab in both groups of patients, more stable and constant in HD patients in comparison with KTR, possibly reflects successful humoral immunity. However, a big proportion of kidney patients remain at high risk for COVID-19 infection considering the new more transmissible variants such as the Omicron variant.
Project description:ObjectivePatients on dialysis are at high risk for severe COVID-19 and associated morbidity and mortality. We examined the humoral response to SARS-CoV-2 mRNA vaccine BNT162b2 in a maintenance dialysis population.DesignSingle-center cohort study.Setting and participantsAdult maintenance dialysis patients at 3 outpatient dialysis units of a large academic center.MethodsParticipants were vaccinated with 2 doses of BNT162b2, 3 weeks apart. We assessed anti-SARS-CoV-2 spike antibodies (anti-S) ∼4-7 weeks after the second dose and evaluated risk factors associated with insufficient response. Definitions of antibody response are as follows: nonresponse (anti-S level, <50 AU/mL), low response (anti-S level, 50-839 AU/mL), and sufficient response (anti-S level, ≥840 AU/mL).ResultsAmong the 173 participants who received 2 vaccine doses, the median age was 60 years (range, 28-88), 53.2% were men, 85% were of Black race, 86% were on in-center hemodialysis and 14% were on peritoneal dialysis. Also, 7 participants (4%) had no response, 27 (15.6%) had a low response, and 139 (80.3%) had a sufficient antibody response. In multivariable analysis, factors significantly associated with insufficient antibody response included end-stage renal disease comorbidity index score ≥5 and absence of prior hepatitis B vaccination response.ConclusionsAlthough most of our study participants seroconverted after 2 doses of BNT162b2, 20% of our cohort did not achieve sufficient humoral response. Our findings demonstrate the urgent need for a more effective vaccine strategy in this high-risk patient population and highlight the importance of ongoing preventative measures until protective immunity is achieved.
Project description:BackgroundCompared with the general population, the immune response to COVID-19 mRNA vaccines is lower in adult kidney transplant recipients (KTRs). However, data is limited for pediatric KTRs. In this study, we aimed to assess humoral and cellular immune responses to the COVID-19 mRNA vaccine in pediatric KTRs.MethodsThis multicenter, prospective, case-control study included 63 KTRs (37 male, aged 12-21 years), 19 dialysis patients, and 19 controls. Humoral (anti-SARS-CoV2 IgG, neutralizing Ab (nAb)) and cellular (interferon-gamma release assay (IGRA)) immune responses were assessed at least one month after two doses of BNT162b2 mRNA vaccine.ResultsAmong COVID-19 naïve KTRs (n = 46), 76.1% tested positive for anti-SARS-CoV-2 IgG, 54.3% for nAb, and 63% for IGRA. Serum levels of anti-SARS-CoV-2 IgG and nAb activity were significantly lower in KTRs compared to dialysis and control groups (p < 0.05 for all). Seropositivity in KTRs was independently associated with shorter transplant duration (p = 0.005), and higher eGFR (p = 0.007). IGRA titer was significantly lower than dialysis patients (p = 0.009). Twenty (43.4%) KTRs were positive for all immune parameters. Only four of 11 seronegative KTRs were IGRA-positive. COVID-19 recovered KTRs had significantly higher anti-SARS-CoV-2 IgG and nAb activity levels than COVID-19 naïve KTRs (p = 0.018 and p = 0.007, respectively).ConclusionsThe humoral and cellular immune responses to SARS-CoV-2 mRNA BNT162b2 vaccine are lower in pediatric KTRs compared to dialysis patients. Further prospective studies are required to demonstrate the clinical efficacy of the mRNA vaccine in KTRs. This prospective study was registered in ClinicalTrials.gov (NCT05465863, registered retrospectively at 20.07.2022). A higher resolution version of the Graphical abstract is available as Supplementary information.
Project description:Coronavirus disease 2019 (COVID-19) is associated with increased morbidity and mortality among kidney transplant recipients (KTRs). The administration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is the only reliable strategy to prevent COVID-19 and alleviate the severity of COVID-19 in this particular population. The aim of this article was to evaluate the clinical protection by vaccines (breakthrough infections, deaths, and hospitalizations) in KTRs. There were 135 KTRs with COVID-19 breakthrough infections for whom patient-level data were available in PubMed and Web of Science. There was a male predominance (61.4%), 97 were given the standard vaccination regimen, and 38 received three or four doses of the vaccine. The median age was 59.0 (IQR: 49.0-69.0) years. A total of 67 patients were hospitalized, and 10 patients died. In 72.6% of cases, triple-maintenance immunosuppression was employed. The deceased patients were older than the survivors (p < 0.05); an age over 60 years was a risk factor for death (p < 0.05). The KTRs with booster vaccines had a longer time interval from the last vaccine to COVID-19 infection and lower hospitalization rates than the individuals who received the standard vaccination regimen (33.3% vs. 54.8%, p < 0.05). The hospitalized patients were older than the outpatients (p < 0.05). Among 16,820 fully vaccinated or boosted KTRs from 14 centers, there were 633 breakthrough infections (3.58%) and 73 associated deaths (0.41%). The center-level breakthrough infection rates varied from 0.21% to 9.29%. These findings highlight the need for booster doses for KTRs. However, more research is needed to define the long-term effectiveness and immunogenicity of booster doses and to identify methods to boost the protective response to vaccination in these immunocompromised patients.
Project description:BackgroundDialysis and kidney transplant patients with moderate-severe COVID-19 have a high mortality rate, around 30%, that is similar in the two populations, despite differences in their baseline characteristics. In these groups, the immunology of the disease has been poorly explored.MethodsThirty-two patients on dialysis or with kidney transplant and SARS-CoV-2 infection requiring hospitalization (COV group) were included in our study. Lymphocyte subsets, dendritic cell (DC) counts and monocyte activation were studied. SARS-CoV-2 anti-spike/anti-nucleocapsid were monitored, and baseline cytokines and chemokines were measured in 10 patients.ResultsThe COV group, compared to healthy subjects and uninfected dialysis/kidney transplant controls, showed lower numbers of CD4 + and CD8 + T cells, Natural-Killer (NK), B cells, plasmacytoid and myeloid DCs, while the proportion of terminally differentiated B-cells was increased. IL6, IL10, IFN-α and chemokines involved in monocyte and neutrophil recruitment were higher in the COV group, compared to uninfected dialysis/kidney transplant controls. Patients with severe disease had lower CD4 + , CD8 + and B-cell counts and lower monocyte HLA-DR expression. Of note, when comparing dialysis and kidney transplant patients with COVID-19, the latter group presented lower NK and pDC counts and monocyte HLA-DR expression. Up to 60 days after symptom onset, kidney transplant recipients showed lower levels of anti-spike antibodies compared to dialysis patients.ConclusionsDuring SARS-CoV-2 infection, dialysis and kidney transplant patients manifest immunophenotype abnormalities; these are similar in the two groups, however kidney transplant recipients show more profound alterations of the innate immune system and lower anti-spike antibody response.