Immune response to SARS-CoV-2 infection and vaccination in patients receiving kidney replacement therapy

CoronaVac-vaccinated kidney transplant recipients with hybrid immunity have strong neutralizing responses against Omicron and Mu variants of SARS-CoV-2

Neutralizing antibody (nAb) responses against SARS-CoV-2 variants after inactivated virus vaccine (CoronaVac) in kidney transplant recipients (KTRs) with or without SARS-CoV-2 infection history remains unclear. We aimed to evaluate the neutralizing antibody responses against emerging SARS-CoV-2 variants after two doses of CoronaVac in these patients. 22.2% of participants had hybrid immunity. Anti-spike IgG antibodies were evidenced in 44% of the patients. nAbs against B.1.111, Mu, and Omicron were detected in 28.5%, 17.9%, and 21.4% of naïve KTRs, respectively. Furthermore, nearly 100% of KTRs with hybrid immunity had nAbs against the variants evaluated. Thus, a significant proportion of infection-naïve KTRs had no detectable nAb titers against Mu and Omicron variants after two doses of the CoronaVac vaccine. However, the nAb titers were significantly higher in patients with hybrid immunity, and it was no association between the immunosuppressive regimen and the seropositivity rate of anti-SARS-CoV-2 neutralizing antibodies. Therefore, hybrid KTRs are protected against COVID-19 by emerging variants able to escape from vaccine-elicited nAbs such as Mu and Omicron.

Antibody response to SARS-CoV-2 natural and breakthrough infection in patients undergoing maintenance hemodialysis: A prospective cohort study over 4 months

Background

Patients undergoing maintenance hemodialysis (MHD) are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, the antibody response of these patients to natural and breakthrough infections remains poorly understood.

Methods

Between January 15, 2023, and February 15, 2023, a total of 53 patients undergoing MHD and diagnosed with SARS-CoV-2 infection at The Affiliated Hospital of Hangzhou Normal University were enrolled. They were categorized into the natural (n = 40) and breakthrough infection groups (n = 13) based on their vaccination status before infection. Comprehensive data, including basic clinical information, vaccination status, and routine post-infection blood parameters, were collected from all participants. Blood specimens were drawn monthly after infection, and SARS-CoV-2 receptor-binding domain (RBD) immunoglobulin (Ig) G and IgM tests were conducted. The study included continuous follow-up over 4 months.

Results

During the acute phase of infection, the SARS-CoV-2 RBD IgM positivity was 5 % in patients undergoing MHD who were naturally infected and 15.4 % in those with breakthrough infections. Four months after infection, SARS-CoV-2 RBD IgG positivity in patients with natural and breakthrough infection was 77.5 % and 100 %, respectively. Patients undergoing MHD with breakthrough infection exhibited higher SARS-CoV-2 RBD IgG titers (751.21 signal-to cutoff ratio, S/CO [interquartile range, IQR, 30.54-1173.63]) than those with natural infections (3.43 S/CO [IQR, 1.12-15.6]) (p < 0.0001). No significant differences were observed in SARS-CoV-2 RBD IgG between males and females or among those aged <70 and ≥70 years. Patients who received three doses of the inactivated vaccine produced significantly higher SARS-CoV-2 RBD IgG levels after infection than those who received one or two doses; these differences were significant.

Conclusions

Although patients undergoing MHD exhibit a low rate of SARS-CoV-2 RBD IgM positivity following infection, those vaccinated with inactivated vaccines can generate elevated SARS-CoV-2 RBD IgG levels, particularly those who receive three doses.

Monitoring strategy of COVID-19 vaccination in dialysis patients based on a multiplex immunodot method: The CovidDial study

INTRODUCTION

COVID-19 vaccine was demonstrated to be effective in dialysis patients, but boosters are mandatory due to a rapid waning of anti-spike antibodies. A vaccination strategy based on immunologic response might be useful to maintain a favorable risk-benefit balance in this vulnerable population.

METHODS

CoviDial is an observational prospective study enrolling 121 dialysis patients to receive a 3-dose mRNA-1273 vaccine according to a uniform schedule. At baseline, months 1, 3, 6, 9, and 12, anti-spike antibodies against four epitopes (S1, S2, ECD-S1 + S2, RBD) were monitored with a multiplex immunodot enzymatic assay. Potential correlation between initial serologic response and subsequent COVID-19 infection was then assessed.

RESULTS

Overall, 96.2% and 96.8% of patients had anti-RBD antibodies at 3 and 12 months, respectively. All antibodies titers significantly decreased at month 6 compared to month 3. Booster vaccine induced a robust serologic response at month 9, but with a waning 3 months later, particularly for anti-S2 (37.2 ± 3.3 vs. 61.3 ± 3.0, p < 0.0001) and anti-S1 + S2 antibodies (68.4 ± 3.3 vs. 88.4 ± 2.3, p = 0.0015). Fifteen patients were later tested positive for SARS-CoV-2. At month 3, mean titers of anti-RBD, anti-S1 + S2, and anti-S2 antibodies were lower in the subsequent SARS-CoV-2 infected cohort (71.57 ± 9.01 vs. 85.79 ± 2.61, p = 0.0131; 41.07 ± 7.96 vs. 61.68 ± 3.56, p = 0.0237; 13.79 ± 5.03 vs. 39.70 ± 3.86, p = 0.0096; respectively).

CONCLUSION

Three doses of mRNA-1273 vaccine induce a robust but time-limited immunologic response in dialysis patients. Lower anti-spike antibodies titers after initial vaccination are associated with a higher risk to subsequently contract SARS-CoV-2, even beyond 6 months.

Partial recovery of SARS-CoV-2 immunity after booster vaccination in renal transplant recipients

The pandemic caused by the SARS-CoV-2 coronavirus has been especially detrimental to patients with end-stage renal disease. History with other vaccines suggests that patients with renal disease may not respond adequately to the SARS-CoV-2 vaccine. The aim of this study is to evaluate the immunity to SARS-CoV-2 mRNA vaccines in renal patients. Post SARS-CoV-2 vaccination first, and after the booster dose, antibodies and cellular immunity were studied in patients on hemodialysis (N = 20), peritoneal dialysis (N = 10) and renal transplantation (N = 10). After the two doses of vaccine, there was an effective immunity in dialysis patients, with 100% seroconversion and 87% detection of cellular immunity (85% in hemodialysis and 90% in peritoneal dialysis). In contrast, in renal transplant recipients there was only 50% seroconversion and cellular immunity was detected in 30% of patients. After the booster dose, all dialysis patients achieved a cellular and antibody immunity, whereas in transplant patients, despite improvement, 20% did not produce antibodies and in 37.5% cellular immunity could not be detected. The mRNA vaccine plus booster performs excellently in dialysis patients, whereas in kidney transplant recipients, despite the booster, complete immunization is not achieved.

Survival benefit of a third dose of the COVID-19 vaccine among hemodialysis patients: A prospective cohort study

BACKGROUND

Hemodialysis (HD) patients are particularly vulnerable to severe coronavirus disease 2019 (COVID-19) due to their immunocompromised state and comorbid conditions. Timely vaccination could be the most effective strategy to reduce morbidity and mortality. However, data on the survival benefit of the COVID-19 vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and death among HD patients are limited, especially during the Omicron-dominant period.

METHODS

In this prospective hospital-based cohort study, we identified HD patients from July 1, 2021, to April 29, 2022. The patients were divided into fully vaccinated and partially vaccinated groups. We compared the humoral response, risk of developing SARS-CoV-2 infection, and all-cause mortality between the two groups.

RESULTS

Among the 440 HD patients included, 152 patients were fully vaccinated, and 288 patients were partially vaccinated. Patients in the fully vaccinated group exhibited higher anti-spike protein receptor-binding domain (S protein RBD) antibody levels and lower risks of all-cause mortality (adjusted hazard ratio, 0.35; 95% confidence interval, 0.17-0.73; p = 0.005) than the partially vaccinated group. However, the risk for SARS-CoV-2 infection did not significantly differ between the two groups. Irrespective of the number of vaccinations, the risk of all-cause mortality was lower in patients with anti-S protein RBD antibody levels in the higher tertile.

CONCLUSION

A third dose of the COVID-19 vaccine was associated with a decreased risk of all-cause mortality among HD patients during the Omicron-dominant period. A higher post-vaccination anti-S protein RBD antibody level was also associated with a lower risk of mortality.

COVID-19 Vaccine Antibody Response in a Single-Center Urban Hemodialysis Unit

BACKGROUND

The longitudinal response to the COVID-19 vaccines among patients on hemodialysis with and without prior SARS-CoV-2 infection has not been well characterized.

METHODS

To guide vaccination strategies in patients on hemodialysis, it is critical to characterize the longevity and efficacy of the vaccine; therefore, we conducted a prospective single-center monthly antibody surveillance study between March 2021 and March 2022 to investigate the dynamic humoral response to a series of COVID-19 mRNA vaccines in patients on hemodialysis with and without prior SARS-CoV-2 infection. Monthly quantitative antibody testing was performed using the Beckman Coulter Access SARS-CoV-2 IgG Antibody Test©, which detects IgG antibodies targeting the receptor binding domain (RBD) of the SARS-CoV-2 spike protein.

RESULTS

This cohort of 30 participants (mean age: 61 ± 3 years) predominantly self-identified as African American (97%) and male (53%). Eight participants (27%) had recovered from COVID-19 (recovered) before the vaccine initiation. All participants received two vaccine doses, and 86.6% received a 6-month booster dose. Among patients naïve to COVID-19, the antibody positivity rate (APR) was 55% post-first-dose, 91% post-second-dose, 50% pre-booster at 6 months, 100% post-booster, and 89% at 6 months post-booster. Recovered patients sustained a consistent 100% APR throughout the year. The naïve patients demonstrated lower peak antibody levels post-second-dose than the recovered patients (17.9 ± 3.2 vs. 44.7 ± 5.6, p < 0.001). The peak antibody levels post-booster showed no significant difference between both groups (27.1 ± 3.9 vs. 37.9 ± 8.2, p = 0.20). Two naïve patients contracted COVID-19 during the follow-up period.

CONCLUSIONS

The patients naïve to COVID-19 exhibited an attenuated and foreshortened antibody response following two doses of the mRNA vaccines compared with the recovered patients, who maintained 100% APR before the booster dose. The 6-month booster dose counteracted declining immunity and stimulated antibody responses in the naïve patients, even in previously non-responsive patients. This observation implies that different booster vaccination strategies might be required for COVID-19-naïve and -recovered patients. Post-vaccination antibody testing may serve as a valuable tool for guiding vaccination strategies.

Antibody response to COVID-19 vaccination in patients on chronic hemodialysis

Purpose

Since patients on hemodialysis (HD) are known to be vulnerable to coronavirus disease 2019 (COVID-19), many studies were conducted regarding the effectiveness of the COVID-19 vaccine in HD patients in Western countries. Here, we assessed antibody response of HD patients for 6 months post-vaccination to identify the duration and effectiveness of the COVID-19 vaccine in the Asian population.

Materials and Methods

We compared antibody response of the COVID-19 vaccine in HD patients with healthy volunteers. Patient and control groups had two doses of ChAdOx1 nCoV-19 and mRNA-1273, respectively. Immunoglobulin G (IgG) was measured before vaccination, 2 weeks after the first dose, 2 and 4 weeks, 3 and 6 months after the second dose. Neutralizing antibody was measured before vaccination and at 2 weeks, 3 and 6 months after second dose. Since the third dose was started in the middle of the study, we analyzed the effect of the third dose as well.

Results

Although antibody production was weaker than the control group (n=22), the patient group (n=39) showed an increase in IgG and neutralizing antibody after two doses. And, 21/39 patients and 14/22 participants had a third dose (BNT162b2 or mRNA-1273 in the patient group, mRNA-1273 in the control group), and it did not affect antibody response in both group. Trend analysis showed IgG and neutralizing antibody did not decrease over time. Age, sex, and HD vintage did not affect antibody production in HD patients. Patients with higher body mass index displayed better seroresponse, while those on immunosuppressants showed poor seroresponse.

Conclusion

Two doses of vaccination led to significant antibody response in HD patients, and the antibody did not wane until 6 months.

Durable Anti-SARS-CoV-2 Antibody Response after mRNA-1273 Booster in Peritoneal Dialysis Patients during the Omicron Wave

Anti-SARS-CoV-2 vaccination of dialysis patients has been proven to be safe and effective to reduce COVID-19-related morbidity and mortality. However, data on the durability of anti-SARS-CoV-2 antibodies post-vaccination in peritoneal dialysis (PD) patients are scarce. In this prospective single-center cohort study we measured anti-SARS-CoV-2 RBD antibodies 3 and 6 months after the 3rd dose of the mRNA-1273 vaccine in 27 adult PD patients and recorded breakthrough infections. Furthermore, in a mixed model analysis, we analyzed potential factors influencing the humoral response following vaccination. Anti-SARS-CoV-2 RBD antibody levels declined from 21,424 BAU/mL at 1 month to 8397 BAU/mL at 3 months and to 5120 BAU/mL at 6 months after the 3rd dose, but remained higher than pre-3rd dose levels (212 BAU/mL). Eight patients (29.6%) were infected with SARS-CoV-2 within six months from the 3rd dose during the Omicron wave. Previous high antibody levels, high glomerular filtration rate (GFR) and low Davies Comorbidity Score were associated with higher anti-SARS-CoV-2 antibody levels after the booster. In conclusion, PD patients exhibited a robust and durable humoral response after a third dose of the mRNA-1273 vaccine. A high GFR and low comorbidity as well as previous high antibody levels predicted a better humoral response to vaccination.

Effects of SARS-CoV-2 vaccination on the severity of COVID-19 infection in patients on chronic dialysis

BACKGROUND

COVID-19 is associated with increased morbidity and mortality in patients with end-stage kidney disease on dialysis. Efficacy of SARS-CoV-2 vaccination to prevent severe COVID-19 disease in end-stage kidney disease patients remains limited. We compared the incidence of COVID-19-related hospitalization and death in dialysis patients based on SARS-CoV-2 vaccine status.

METHODS

Retrospective study of adults on chronic dialysis within Mayo Clinic Dialysis System in the Midwest (USA) between April 1st, 2020 and October 31st, 2022, who had a laboratory test positive for SARS-CoV-2 by PCR. Incidence of both COVID-19-related hospitalization and death were compared between vaccinated and unvaccinated patients.

RESULTS

SARS-CoV-2 infection was identified in 309 patients, including 183 vaccinated and 126 unvaccinated. The incidence of death (11.1% vs 3.8%, p = 0.02) and hospitalization (55.6% vs 23.5%, p < 0.001) was significantly higher in unvaccinated compared to vaccinated patients. Age at infection, sex, Charlson comorbidity index, dialysis modality, and hospital stays did not differ between the two groups. The incidence of hospitalization was significantly higher in partially vaccinated (63.6% vs 20.9%, p = 0.004) and unboosted (32% vs 16.4%, p = 0.04) patients compared to fully vaccinated and boosted, respectively. Among the 21 patients who died in the whole cohort, 47.6% (n = 10) died during the pre-vaccine period. The composite risk of death or hospitalization was lower among vaccinated patients after adjusting for age, sex and Charlson comorbidity index (OR 0.24, 95% CI 0.15-0.40).

CONCLUSIONS

This study supports the use of SARS-CoV-2 vaccination to improve COVID-19 outcomes in patients on chronic dialysis.

Serological Response to SARS-CoV-2 Vaccine in Hemodialyzed Patients and the Association with Later COVID-19 Positivity

BACKGROUND

The effectiveness of the COVID-19 vaccine may differ in hemodialysis patients. The aim of this prospective multicenter study was to determine the degree of serological response to the SARS-CoV-2 vaccine in the population of dialysis patients and its association with later SARS-CoV-2 infections.

METHODS

A blood sample was taken for the determination of COVID-19 serological status (IgG antibodies) in 706 dialysis patients 16 weeks after vaccination with the second dose (Pfizer-BioNTech).

RESULTS

Only 314 (44.5%) hemodialyzed patients had a satisfactory response to the COVID-19 vaccine. Eighty-two patients (11.6%) had a borderline response, while 310 patients (43.9%) had an unsatisfactory (negative) post-vaccinal antibody titer. A longer dialysis vintage had an increased odds ratio (OR) of 1.01 for the occurrence of COVID-19 positivity after vaccination. In the group of subsequently positive patients, 28 patients (13.6%) died from complications of COVID-19. We have found differences in mean survival time between patients with and without appropriate responses to vaccination in favor of patients with a satisfactory serological response.

CONCLUSIONS

The results showed that the dialysis population will not have the same serological response to the vaccine as the general population. The majority of dialysis patients did not develop a severe clinical picture or die at the time of positivity for COVID-19.

Cellular and Humoral Responses in Dialysis Patients after Vaccination with the BNT162b2 or mRNA-1273 Vaccines

The outbreak of SARS-CoV-2 has raised considerable concern about the detrimental effects it can induce in public health, with the interest of the scientific community being focused on the development of preventive and therapeutic approaches. Patients with end-stage renal disease (ESRD) are amongst vulnerable populations for critical illness owing to the presence of other comorbidities, their defective immune system, and their inability of self-isolation. To date, vaccination constitutes the most promising method to manage viral dispersion. Therefore, it is particularly important to investigate the effectiveness of available vaccines against SARS-CoV-2 in this risk group. Here, we summarize initial experience regarding the humoral and cellular immune responses elicited in dialysis patients after completion of the recommended vaccination regimen, as well as after booster dose administration, with one of the two mRNA vaccines, namely, BNT162b2 and mRNA-1273. In conclusion, a significantly diminished and delayed immune pattern was observed in ESRD patients compared to healthy population, with a peak in antibody titers occurring 3-5 weeks after the second dose. A booster dose significantly augmented the immune response in dialysis patients with either mRNA-based vaccine. Variables adversely correlating with the weak immunogenicity observed in dialysis patients include immunosuppressive therapy, older age, comorbidities, longer time in hemodialysis treatment, and higher body mass index. On the contrary, previous COVID-19 infection and administration of the mRNA-1273 vaccine are deemed to induce a more favorable immune response. Further investigation is needed to thoroughly understand the efficacy of mRNA-based vaccines in hemodialysis patients and define predictive factors that can influence it.

Humoral response after BNT162b2 vaccine in Japanese hemodialysis patients

Background

Hemodialysis patients are more likely to be severely affected if infected by COVID-19. Contributing factors include chronic kidney disease, old age, hypertension, type 2 diabetes, heart disease, and cerebrovascular disease. Therefore, action against COVID-19 for hemodialysis patients is an urgent issue. Vaccines are effective in preventing COVID 19 infection. In hemodialysis patients, however, responses to hepatitis B and influenza vaccines are reportedly weak. The BNT162b2 vaccine has shown an efficacy rate of about 95% in the general population, but as far as we know there are only several reports of efficacy data in hemodialysis patients in Japan.

Methods

We assessed serum anti-SARS-CoV-2 IgG antibody (Abbott SARS-CoV-2 IgG II Quan) in 185 hemodialysis patients and 109 health care workers. The exclusion criterion was positivity for SARS-CoV-2 IgG antibody before vaccination. Adverse reactions to BNT162b2 vaccine were evaluated through interviews.

Results

Following vaccination, 97.6% of the hemodialysis group and 100% of the control group were positive for the anti-spike antibody. The median level of anti-spike antibody was 2,728.7 AU/mL (IQR, 1,024.2-7,688.2 AU/mL) in the hemodialysis group and 10,500 AU/ml (IQR, 9,346.1-2,4500 AU/mL) in the health care workers group. The factors involved in the low response to the BNT152b2 vaccine included old age, low BMI, low Cr index, low nPCR, low GNRI, low lymphocyte count, steroid administration, and complications related to blood disorders.

Conclusions

Humoral responses to BNT162b2 vaccine in hemodialysis patients are weaker than in a healthy control sample. Booster vaccination is necessary for hemodialysis patients, especially those showing a weak or non-response to the two-dose BNT162b2 vaccine.Trial registration UMIN, UMIN000047032. Registered 28 February 2022, https://center6.umin.ac.jp/cgi-bin/ctr/ctr_reg_rec.cgi.

Kidney Transplantation in Patients With the History of SARS-CoV-2 Infection

BACKGROUND

The aim of this study is to present the experience and results of kidney transplantation in patients with the history of SARS-CoV-2 infection.

METHODS

We retrospectively analyzed waitlisted patients who had a history of SARS-CoV-2 infection and offered a kidney transplant between March 2020 and December 2021.

RESULTS

Of the 97 waitlisted potential kidney transplant recipients who were offered a kidney, 13 (13.4%) had a history of SARS-CoV-2 infection. All patients were tested negative for SARS-CoV-2 at the time of the kidney offer. Successful transplantation was performed in 9 patients (5 male; average age was 40.8 years), with the average time between SARS-CoV-2 infection and transplantation of 8 months. Four of 13 patients with a history of SARS-CoV-2 infection were finally not transplanted, with 2 patients not eligible for transplantation due to significant post-COVID findings in routine pretransplant chest CT scans, and 2 patients were not transplanted because of poor donor organ quality.

CONCLUSIONS

Kidney transplantation after SARS-CoV-2 infection is possible in a setting of full recovery from acute infection, negative PCR test, and no pneumonic infiltrates on chest CT scan. A growing number of waitlisted patients with a history of SARS-CoV-2 infection imposes the need for decision-making tools and guidelines for risk/benefit assessment in these patients.

COVID-19 Vaccination in Kidney Transplant Candidates and Recipients

Kidney transplant candidates and kidney transplant recipients (KTRs) are at particular risk of severe complications of COVID-19 disease. In Western countries, mortality in affected hospitalized KTRs ranges between 19% and 50%. COVID-19 vaccination remains the most important measure to prevent the severity of infection in candidates and recipients of kidney transplant. However, the uraemic condition may affect the vaccine-induced immunity in patients with advanced chronic kidney disease (CKD) and in KTRs. Retention of uraemic toxins, dysbiosis, dysmetabolism, and dialysis can diminish the normal response to vaccination, leading to dysfunction of inflammatory and immune cells. In KTRs the efficacy of vaccines may be reduced by the immunosuppressive medications, and more than half of kidney transplant recipients are unable to build an immune response even after four administrations of anti-COVID-19 vaccines. The lack of antibody response leaves these patients at high risk for SARS-CoV-2 infection and severe COVID-19 disease. The aim of the present review is to focus on the main reasons for the impaired immunological response among candidates and kidney transplant recipients and to highlight some of the present options available to solve the problem.

Immune response after COVID-19 vaccination among patients with chronic kidney disease and kidney transplant

BACKGROUND

Vaccination of patients with chronic kidney disease (CKD) and kidney transplants (KTs) may achieve a less robust immune response. Understanding such immune responses is crucial for guiding current and future vaccine dosing strategies.

METHODS

This prospective, observational study estimated the immunogenicity of humoral and cellular responses of two SARS-CoV-2 vaccines in different patient groups with CKD compared with controls. Secondary outcomes included adverse events after vaccination and the incidence of COVID-19 breakthrough infection, including illness severity.

RESULTS

In total, 212 patients received ChAdOx1 nCoV-19 (89.62 %) or inactivated vaccines (10.38 %).The antibody response against the S protein was analyzed at T0 (before the first injection), T1 (before the second injection), and T2 (12 weeks after the second injection). Seroconversion occurred in 92.31 % of controls at T2 and in 100 % of patients with CKD, 42.86 % undergoing KT, 80.18 % of hemodialysis (HD), and 0 % of patients undergoing continuous ambulatory peritoneal dialysis (CAPD) at T2 of the ChAdOx1 nCoV-19 vaccine. Neutralizing antibody levels by surrogate virus neutralization test were above the protective level at T2 in each group. The KT group exhibited the lowest neutralizing antibody and T cell response. Blood groups O and vaccine type were associated with good immunological responses. After the first dose, 14 individuals (6.6 out of the total population experienced COVID-19 breakthrough infection.

CONCLUSION

Immunity among patients with CKD and HD after vaccination was strong and comparable with that of healthy controls. Our study suggested that a single dose of the vaccine is not efficacious and delays may result in breakthrough infection. Some blood groups and types of vaccine can affect the immune response.

The Effect of a Booster Dose mRNA Vaccine on COVID-19 Infection in Kidney Transplant Recipients after Inactivated or Viral Vector Vaccine Immunization

The mortality rate after novel coronavirus infection, which causes severe acute respiratory distress syndrome (SARS-CoV-2), is much higher in kidney transplant recipients (KTRs) compared to the general population. Seroconversion after vaccination is also lower, and breakthrough infection is much higher. Many studies reported seroconversion rate after a booster (third) dose of vaccine but clinical outcomes received less attention. Here, we reported the impact of an mRNA vaccine booster dose on clinical outcomes of KTRs with SARS-CoV-2 infection. A total of 183 KTRs with SARS-CoV-2 infection were identified. Of 183 KTRs, 146 KTRs had sufficient data for analysis and were included in this study. Forty-eight patients (32.9%) received zero to 1 doses of vaccine (Group 1), thirty-one (21.2%) received two doses (Group 2), and sixty-seven (45.9%) received a booster dose (Group 3). Pneumonia developed in 50%, 23%, and 10% in Group 1, 2, and 3 (p < 0.001). Hospital admission requirement was 81%, 48%, and 12% (p < 0.001). Mortality rate was 26%, 3%, and 3% (p = 0.001). A multivariate analysis showed that only diabetes adversely affects mortality while the booster dose of the vaccine significantly reduced mortality. The booster dose of the vaccine is strongly recommended in all KTRs especially those with diabetes. Our study also suggested the timing of the booster dose vaccine to be administered within 4 months after the second dose.

Immune Responses after a Third Dose of mRNA Vaccine Differ in Virus-Naive versus SARS-CoV-2- Recovered Dialysis Patients

BACKGROUND AND OBJECTIVES

After two doses of mRNA vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), patients on dialysis show a defective humoral response, but a third dose could increase anti-SARS-CoV-2 spike IgG titers. Responses could be different in virus-naive and SARS-CoV-2-recovered patients on dialysis. However, characterization of memory B cell response after three doses is lacking.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We evaluated the dynamics of antireceptor binding domain IgG titers and antireceptor binding domain memory B cells until 6 months after two and three doses (administered within 6 months after the second dose) of mRNA vaccine in SARS-CoV-2-recovered and virus-naive dialysis populations. Results were analyzed by ordinary one-way ANOVA, the Kruskal-Wallis test, or the Wilcoxon matched-pairs test as appropriate.

RESULTS

In total, 108 individuals (59 patients on dialysis and 49 controls) were included. In virus-naive patients on dialysis, antireceptor binding domain IgG response was quantitatively lower after two doses compared with healthy controls, but IgG titers increased by three-fold after three doses (P=0.008). In SARS-CoV-2-recovered patients on dialysis, antireceptor binding domain IgG titers after two doses were significantly higher compared with virus-naive patients on dialysis but did not significantly increase after a third dose. Regarding memory B cell response, we detected receptor binding domain-specific memory B cells at similar proportions in virus-naive patients on dialysis and vaccinated controls after two doses. Moreover, a strong receptor binding domain-specific memory B cell expansion was observed after the third dose in virus-naive patients on dialysis (5.5-fold; P<0.001). However, in SARS-CoV-2-recovered patients on dialysis, antireceptor binding domain memory B cells remained unchanged after the third dose.

CONCLUSIONS

The third dose of mRNA vaccine given within 6 months after the second dose boosts serologic and memory response in virus-naive patients but not in SARS-CoV-2-recovered patients on dialysis.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

COVID-19: SARS-CoV-2 Specific Memory B and T-CD4+ Cells (MEMO-COV2), NCT04402892.

Kidney implications of SARS-CoV2 infection in children

Research indicates that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection can impact every organ, and the effects can range from asymptomatic to severe disease. Since it was first discovered in December 2019, our understanding has grown about its impact on kidney disease. In general, children have less severe disease than adults, and this tendency appears to extend to special pediatric kidney populations (e.g., chronic kidney disease and immunosuppressed patients with solid organ transplants or nephrotic syndrome). However, in a fraction of infected children, SARS-CoV2 causes an array of kidney manifestations, ranging from acute kidney injury to thrombotic microangiopathy, with potential implications for increased risk of morbidity and mortality. Additional considerations surround the propensity for clotting extracorporeal circuits in children with SARS-CoV2 infection that are receiving kidney replacement therapy. This review provides an update on our current understanding of SARS-CoV2 for pediatric nephrologists and highlights knowledge gaps to be addressed by future research during this ongoing pandemic, particularly the social disparities magnified during this period.

Survey of current transplant center practices regarding COVID-19 vaccine mandates in the United States

An electronic survey canvassing current policies of transplant centers regarding a COVID-19 vaccine mandate for transplant candidates and living donors was distributed to clinicians at US solid organ transplant centers performing transplants from October 14, 2021-November 15, 2021. Responses were received from staff at 141 unique transplant centers. These respondents represented 56.4% of US transplant centers, and responding centers performed 78.5% of kidney transplants and 82.4% of liver transplants in the year prior to survey administration. Only 35.7% of centers reported implementing a vaccine mandate, while 60.7% reported that vaccination was not required. A minority (42%) of responding centers with a vaccine mandate for transplant candidates also mandated vaccination for living organ donors. Centers with a vaccine mandate most frequently cited clinical evidence supporting the efficacy of pre-transplant vaccination (82%) and stewardship obligations to ensure organs were transplanted into the lowest risk patients (64%). Centers without a vaccine mandate cited a variety of reasons including administrative, equity, and legal considerations for their decision. Transplant centers in the United States exhibit significant heterogeneity in COVID-19 vaccination mandate policies for transplant candidates. While all centers encourage vaccination, most centers have not mandated COVID-19 vaccination for candidates and living donors, citing administrative opposition, legal prohibitions, and concern about equity in access to transplants.

Comparison of COVID-19 Inactivated Virus Vaccine Immunogenicity Between Healthy Individuals and Patients on Hemodialysis: A Single-Center Study From Pakistan

Introduction

This study compares the immune response after coronavirus disease 2019 (COVID-19) inactivated virus vaccine between healthy individuals (HI) and patients on hemodialysis (HD).

Methods

In this cross-sectional, comparative study, the presence or absence of immunoglobulin G (IgG) anti-S antibody and IgG anti-S antibody titer was compared between HI, and patients on HD after two doses of COVID-19 vaccine.

Results

A total of 81 participants, 50 (61.7%) HD patients and 31 (38.3%) HI, were studied. The mean age was 52.9±12 in HD patients and 42±12.4 in HI. Vaccination responder rates were 80.6% in HI and 72% in HD patients after the first dose (p=0.38) and 93.5% in HI and 94% in HD at the third week of the second dose of the vaccine (p=0.93). The mean IgG antibody titer was 156.3±113.8 in HI and 143.4 ± 117.8 in HD patients (p=0.538) after the first dose and 186.7 ± 97.9 in HI and 180.6 ± 105.8 in HD patients (p=0.552) at three weeks of the second dose. No statistically significant difference was found in antibody titer with respect to gender, age, vaccine (BBIBP-CorV or Conovac), and hypertension. Diabetic HD patients had a lower antibody titer than non-diabetic HD patients (p=0.03) while participants who had a history of COVID-19 infection had a higher IgG titer (p = 0.001). The levels of IgG titer in the same patient increased, corresponding to the doses of vaccine (p <0.001). No HD patient developed COVID-19 infection till the third week of vaccination.

Conclusion

This study demonstrates a similar humoral response after COVID-19 inactivated virus vaccination in HD patients and HI. The response was lower among diabetic patients on HD and better in those with previous COVID-19 infection.

Longevity of Humoral Response Six Months Following BNT162b2 Vaccine in Dialysis Patients

Background

End-stage kidney disease substantially increases the risk of severe COVID-19. However, despite early robust immunogenicity of the mRNA-SARS-CoV-2 vaccination in patients with hemodialysis, the longevity of humoral response in this high-risk population is still unknown.

Methods

A prospective cohort study aimed to evaluate the longevity of serologic response in patients with hemodialysis, compared with a control group, 6 months following the second dose of the BNT162b2 vaccine. We assessed antibody response by quantitative measurement of IgG antibodies against the receptor-binding domain of the Spike protein (anti-S1-RBD IgG). Study outcomes were defined as a seropositivity rate and log-transformed anti-S1-RBD IgG levels at 6 months, and the change in antibody levels between 3 and 6 months.

Findings

The cohort included 104 patients with hemodialysis and 84 controls. At a median time of 184 days (IQR, 183–188) following the second dose of the vaccine, 83/104 (79.8%) patients with hemodialysis maintained seropositivity for the anti-S1-RBD IgG level compared to 83/84 (98.8%) in the control group (p < 0.001). The log-transformed antibody level was significantly lower in the hemodialysis group (2.23 ± 0.39 log AU/ml vs. 2.69 ± 0.65 log AU/ml, respectively, p < 0.001). Older age and hypoalbuminemia were the only variables that were found to be associated with reduced log-transformed antibody levels in univariate and multivariate analysis. There was no interaction between dialysis status and an antibody-level decline rate (p = 0.972).

Conclusion

Among patients with hemodialysis, a seropositivity rate and anti-S1-RBD antibody titers were substantially reduced compared with a control group, at 6 months following the second dose of the BNT162b2 vaccine. These findings support the prioritization of patients with hemodialysis for a third “booster” dose.

Humoral Immune Response of SARS-CoV-2 Infection and Anti-SARS-CoV-2 Vaccination in Renal Transplant Recipients

Vaccination-induced SARS-CoV-2 neutralizing antibodies are required for herd immunity. Vaccine availability and poor vaccine response in renal transplant recipients (RTRs) remain a concern. There is no report on the efficacy of Covaxin and Covishield vaccines in RTRs. We recruited 222 live donors RTRs and analyzed the serum titer of anti-SARS-CoV-2 spike protein antibody by chemiluminescent magnetic microparticle immunoassay. Patients were categorized into three groups: group1 with SARS-CoV-2 infection and no vaccination (n = 161); group 2 with only vaccination and no SARS-CoV-2 infection (n = 41); and group 3 with both vaccination and SARS-CoV-2 infection (n = 20). Overall seroconversion rate was 193/222 (86.9%) with a median titer 1095.20 AU/mL. The median IgG titer value in group 1 was 647.0 AU/mL; group 2 was 1409.0 AU/mL; and group 3 was 1831.30 AU/mL. Covaxin associated seroconversion was observed in 16/19 (84.21%), with a median titer of 1373.90 AU/mL compared to that of Covishield 32/42 (76.19%), whose median titer was 1831.10 AU/mL. The seroconversion rate due to SARS-CoV-2 infection was 145 (90.06%), it was lowest with the vaccination-only group (70.7%), and with both vaccination and SARS-CoV-2 infection group it was highest (95%). In RTRs, SARS-CoV-2 infection and both Covaxin and Covishield vaccination effectively induce a humoral immune response against the SARS-CoV-2 spike protein; however, seroconversion rate was lower and the antibody titer was higher with vaccine than infection.

Vaccination and COVID-19 Dynamics in Dialysis Patients

BACKGROUND AND OBJECTIVES

Dialysis patients have a high mortality risk after coronavirus disease 2019 (COVID-19) and an altered immunologic response to vaccines, but vaccine clinical effectiveness remains unknown in this population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using Bayesian multivariable spatiotemporal models, we estimated the association between vaccine exposure and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) severe infections (with hospital admission) in dialysis patients from simultaneous incidence in the general population. For dialysis patients, cases were reported within the French end-stage kidney disease REIN registry from March 11, 2020, to April 29, 2021, and vaccine exposure (first dose) was reported in weekly national surveys since January 2021. Cases in the general population were obtained from the national exhaustive inpatient surveillance system (SI-VIC database), and vaccination coverage (first dose) was obtained from the national surveillance system (VAC-SI database).

RESULTS

During the first wave, incidence in dialysis patients was approximately proportional to the general population. However, we showed a lower relative incidence for dialysis patients during the second wave (compared with that observed in nondialysis patients), suggesting an effect of prevention measures. Moreover, from the beginning of the vaccination rollout, incidence in dialysis patients was lower compared with predictions based on the first and second waves. Adding vaccination coverages in dialysis and nondialysis patients as predictors allowed the reported cases to be fit correctly (3685 predicted cases, 95% confidence interval, 3552 to 3816, versus 3620 reported). Incidence rate ratios were 0.37 (95% confidence interval, 0.18 to 0.71) for vaccine exposure in dialysis patients and 0.50 (95% confidence interval, 0.40 to 0.61) per 10% higher in vaccination coverage in the same-age general population, meaning that vaccine exposure in dialysis patients and the general population was independently associated with lower hospitalization rate of dialysis patients.

CONCLUSIONS

Our findings suggest that vaccination may yield a protective effect against severe forms of COVID-19 in dialysis patients, despite altered immunologic vaccine responses.

Poor neutralization and rapid decay of antibodies to SARS-CoV-2 variants in vaccinated dialysis patients

Patients on dialysis are at risk of severe course of SARS-CoV-2 infection. Understanding the neutralizing activity and coverage of SARS-CoV-2 variants of vaccine-elicited antibodies is required to guide prophylactic and therapeutic COVID-19 interventions in this frail population. By analyzing plasma samples from 130 hemodialysis and 13 peritoneal dialysis patients after two doses of BNT162b2 or mRNA-1273 vaccines, we found that 35% of the patients had low-level or undetectable IgG antibodies to SARS-CoV-2 Spike (S). Neutralizing antibodies against the vaccine-matched SARS-CoV-2 and Delta variant were low or undetectable in 49% and 77% of patients, respectively, and were further reduced against other emerging variants. The fraction of non-responding patients was higher in SARS-CoV-2-naïve hemodialysis patients immunized with BNT162b2 (66%) than those immunized with mRNA-1273 (23%). The reduced neutralizing activity correlated with low antibody avidity. Patients followed up to 7 months after vaccination showed a rapid decay of the antibody response with an average 21- and 10-fold reduction of neutralizing antibodies to vaccine-matched SARS-CoV-2 and Delta variant, which increased the fraction of non-responders to 84% and 90%, respectively. These data indicate that dialysis patients should be prioritized for additional vaccination boosts. Nevertheless, their antibody response to SARS-CoV-2 must be continuously monitored to adopt the best prophylactic and therapeutic strategy.

Immunogenicity and reactogenicity of homologous mRNA-based and vector-based SARS-CoV-2 vaccine regimens in patients receiving maintenance dialysis

Patients receiving maintenance dialysis (MD) are vulnerable to COVID-19-related morbidity and mortality. Currently, data on SARS-CoV-2-specific cellular and humoral immunity post-vaccination in this population are scarce.

We conducted a prospective single-center study exploring the specific cellular (interferon-γ and interleukin-2 ELISpot assays) and humoral immune responses (dot plot array and chemiluminescent microparticle immunoassay [CMIA]) at 4 weeks and 6 weeks following a single dose or a complete homologous dual dose SARS-CoV-2 vaccine regimen in 60 MD patients (six with a history of COVID-19).

Our results show that MD patients exhibit a high seroconversion rate (91.7%) but the anti-spike IgG antibodies (CMIA) tend to wane rapidly after full immunization. Only 51.7% of the patients developed T cell immune response. High anti-spike IgG antibodies may predict a better cellular immunity. While patients with prior COVID-19 showed the best response after one, SARS-CoV-2-naïve patients may benefit from a third vaccine injection.

Mandating COVID-19 vaccination prior to kidney transplantation in the United States: No solutions, only decisions

The question of whether transplant clinicians should mandate COVID-19 vaccination as a condition of transplant candidacy is complex. A vaccine mandate may be defensible on the grounds that transplant clinicians are obligated to ensure transplantation is conducted safely, and in a manner that entails the best use of a scarce public good. However, mandate proponents will inexorably predicate their arguments on contingent clinical judgments that meliorate rather than resolve core value disagreements. Vaccine mandates are conceivably defensible on narrow grounds, but may prove to be purchased at the expense of an attenuation of shared decision-making, proffering claims of risk reduction from a vaccine mandate beyond what the current evidence base supports, and unintentionally exacerbating durable inequities in access to transplantation.

Humoral Immunity of BBIBP-CorV (Sinopharm) in kidney transplant recipients: Is it time to revise vaccination strategies

BACKGROUND

The mortality of COVID-19 is high in transplant patients, and effective vaccination is aimed to reduce severe disease and mortality.

METHODS

We conducted a cross-sectional study to evaluate humoral and cellular response to two 4μg-doses of BBIBP-CorV vaccine in 100 kidney transplant recipients, using Anti-Spike IgG, Total Anti-RBD, Neutralizing Ab level (ELISA), and interferon-gamma release assay (IGRA).

RESULTS

Seroconversion was evaluated 85.84 ± 30.72 days after second dose. 58% of all and 43.05% infection-naïve participants have developed at least one of the tested antibodies. IGRA was positive in 30.7% of tested transplant recipients. 60% of the participants had either humoral or cellular response to COIVD-19. Only age was independently linked to seropositivity of any degree after vaccination (p<0.05). COVID-naïve patients older than 60 years developed significantly less neutralizing antibody. (p value: 0.011). Six patients developed mild COVID infection more than a month after 2^nd dose of vaccine (54.5 ± 20.8 days). No vaccine-related adverse effects were reported, except self-limited mild to moderate fever and injection site pain.

CONCLUSION

BBIBP-CorV vaccine can be used safely in kidney transplant recipient, although impaired cellular and humoral immunity necessitates adjustments in vaccination strategies, like higher (8μg-doses), forth booster dose, or boost with different platform vaccine. This article is protected by copyright. All rights reserved.

Response to Vaccination Against SARS-CoV-2 in Patients With Antineutrophil Cytoplasmic Antibody-Associated Vasculitis With Renal Involvement

Background

Patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) present with multisystem disease including renal impairment. The treatment for AAV involves a high burden of immunosuppression. Patients with renal involvement are treated especially intensively. As a result, we identified these patients as being potentially at high risk of failure to seroconvert to COVID-19 vaccination.

Methods

We collected data on seroconversion response rates to COVID-19 vaccination in a multi-ethnic cohort of patients with AAV and renal involvement treated at a busy tertiary nephrology centre as part of a retrospective review of patient notes. Blood samples were taken following vaccination with either Pfizer or Astra-Zeneca COVID-19 vaccines and median fluorescence intensity was measured using the validated MULTICOV-Ab Magnetic Luminex^Ⓡ Assay. We also evaluated whether seroconversion was affected by immunosuppression regimen.

Results

81 patients were included. The mean age was 62, and there were 49 (60%) females. 55 patients had a blood test after the first dose; 46 after the second dose. Patients were in remission with a median BVAS of 0 (IQR 2). Seroconversion after the first dose with either vaccine was 35/55 (63.6%). After the second it was 38/46 (82.6%). Subgroup analyses revealed a trend to impaired seroconversion in non-white versus white patients (77.8 vs. 81.7% (p = 0.69) after the first dose of vaccine and in those treated with Rituximab in the last 12 months (73.3 vs. 87.1%, p = 0.41).

Conclusions

These data offer real-world evidence of lower seroconversion in response to vaccination with one dose in patients with AAV and renal involvement than the general UK population. After two doses, seroconversion is in line with national data. These data provide a rationale for hospital-led identification of patients most at risk of COVID-19 and underscore the importance of local connexions between hospitals and their communities. These data provide further support for targeting booster vaccination programmes to vulnerable patient cohorts. They add to the growing evidence of reduced seroconversion in response to vaccination in patients with renal disease of any cause.

Poor neutralization and rapid decay of antibodies to SARS-CoV-2 variants in vaccinated dialysis patients

Patients on dialysis are at risk of severe course of SARS-CoV-2 infection. Understanding the neutralizing activity and coverage of SARS-CoV-2 variants of vaccine-elicited antibodies is required to guide prophylactic and therapeutic COVID-19 interventions in this frail population. By analyzing plasma samples from 130 hemodialysis and 13 peritoneal dialysis patients after two doses of BNT162b2 or mRNA-1273 vaccines, we found that 35% of the patients had low-level or undetectable IgG antibodies to SARS-CoV-2 Spike (S). Neutralizing antibodies against the vaccine-matched SARS-CoV-2 and Delta variant were low or undetectable in 49% and 77% of patients, respectively, and were further reduced against other emerging variants. The fraction of non-responding patients was higher in SARS-CoV-2-naïve hemodialysis patients immunized with BNT162b2 (66%) than those immunized with mRNA-1273 (23%). The reduced neutralizing activity correlated with low antibody avidity. Patients followed up to 7 months after vaccination showed a rapid decay of the antibody response with an average 21- and 10-fold reduction of neutralizing antibodies to vaccine-matched SARS-CoV-2 and Delta variant, which increased the fraction of non-responders to 84% and 90%, respectively. These data indicate that dialysis patients should be prioritized for additional vaccination boosts. Nevertheless, their antibody response to SARS-CoV-2 must be continuously monitored to adopt the best prophylactic and therapeutic strategy.

The Humoral Immune Response to BNT162b2 Vaccine Is Associated With Circulating CD19+ B Lymphocytes and the Naïve CD45RA to Memory CD45RO CD4+ T Helper Cells Ratio in Hemodialysis Patients and Kidney Transplant Recipients

Background

The humoral and cellular immune responses to SARS-COV-2 vaccination remain to be elucidated in hemodialysis (HD) patients and kidney transplant recipients (KTRs), considering their baseline immunosuppressed status. The aim of our study was to assess the associations of vaccine-induced antibody responses with circulating lymphocytes sub-populations and their respective patterns of alterations in maintenance HD patients and KTRs.

Materials and Methods

We included 34 HD patients and 54 KTRs who received two doses of the mRNA-vaccine BNT162b2. Lymphocyte subpopulations were analyzed by flow cytometry before vaccination (T0), before the second vaccine dose (T1) and 2 weeks after the second dose (T2). The anti-SARS-CoV2 antibody response was assessed at T1 and at T2.

Results

31 HD patients (91.8%) and 16 KTRs (29.6%) became seropositive at T2. HD patients who became seropositive following the first dose displayed higher CD19+ B lymphocytes compared to their seronegative HD counterparts. A positive correlation was established between CD19+ B cells counts and antibody titers at all time-points in both groups (p < 0.001). KTRs showed higher naïve CD4+CD45RA+ T helper cells compared to HD patients at baseline and T2 whereas HD patients displayed higher memory CD45RO+ T cells compared to KTRs at T2. The naïve CD4+CD45RA to memory CD4+CD45RO+ T helper cells fraction was negatively associated with antibody production in both groups.

Conclusions

Our study provides a potential conceptual framework for monitoring vaccination efficacy in HD patients and KTRs considering the correlation established between CD19+ B cells, generation of memory CD4+ T helper cells and anti SARS-CoV2 antibody response to vaccination.

Antibody Response and Safety After mRNA-1273 SARS-CoV-2 Vaccination in Peritoneal Dialysis Patients - the Vienna Cohort

Background

Dialysis patients are at high risk for a severe clinical course after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Safety and early immune responses after mRNA-based vaccination have been reported mostly in patients on hemodialysis (HD), whereas reports of peritoneal dialysis (PD) patients remain rare.

Methods

In this retrospective observational study, 39 PD patients had received two doses of the mRNA-1273 Moderna^® vaccine. We analyzed SARS-CoV-2 Spike (S) antibody titers 4 weeks after each dose of mRNA-1273 and report local and systemic side effects in PD patients that occurred within one week after each mRNA-1273 dose. Using a quantile regression model we examined factors that might influence SARS-CoV-2 S antibody levels in PD patients.

Results

Four weeks after the first dose of mRNA-1273 vaccine 33 of 39 (84.6%) PD patients seroconverted and presented with 6.62 U/mL (median; IQR 1.57-22.5) anti-SARS-CoV-2 S antibody titers. After the second dose, 38 of 39 (97.4%) PD patients developed anti-SARS-CoV-2 S antibodies and titers increased significantly (median 968 U/mL; IQR 422.5-2500). Pain at the injection site was the most common local adverse event (AE) (71%). Systemic AEs occurring after the first dose were mostly fatigue (33%) and headache (20%). No severe systemic AEs were reported after the first injection. After the second dose the incidence and the severity of the systemic AEs increased. The most common systemic AEs were: fatigue (40.5%), headache (22.5%), joint pain (20%), myalgia (17.5%) and fever (13%). Lower Davies Comorbidity Score (p=0.04) and shorter dialysis vintage (p=0.017) were associated with higher antibody titers after the first dose. Patients with higher antibody titers after the first dose tended to have higher antibody titers after the second dose (p=1.53x10^-05).

Conclusions

Peritoneal dialysis patients in this cohort had a high seroconversion rate of 97.4%, showed high antibody titers after full vaccination and tolerated the anti-SARS-CoV-2 mRNA-1273 vaccine well without serious adverse events.

Immune Response after SARS-CoV-2 Vaccination in Kidney Transplant Patients

Background and Objectives: The prospective study was conducted to evaluate humoral and cellular immune responses after two doses of BNT162b2 (Pfizer-BioNTech) vaccine and possible relation with other factors (medication, etc.) in kidney transplant patients. Materials and Methods: Out of 167 vaccinated patients, 136 agreed to a follow-up visit three to six weeks after vaccination. Results: Only 39 patients (29%) developed antibody response against SARS-CoV-2 (≥35.2 binding antibody units (BAU)/mL) after full vaccination. Multivariate binary logistic regression analysis showed that predictive factors for good antibody response to the COVID-19 vaccine were better kidney function, higher hemoglobin level, and no use of mycophenolate mofetil for immunosuppression. For seropositive kidney transplant patients there was a significant negative correlation between anti-SARS-CoV-2 antibody titer and CD4/CD8 ratio (Spearman's correlation coefficient -0.4, p = 0.02), percentage of CD19+ cells (r = -0.37, p = 0.02), and a positive correlation with percentage of CD8+ cells (r = 0.4, p = 0.01). There was an increase of total leucocyte count after vaccination in the total studied population, and in the group of responders. Conclusions: Only one third of kidney transplant patients develop sufficient antibody responses after full COVID-19 vaccination with Pfizer-BioNTech. Better kidney function, higher hemoglobin level, and no use of mycophenolate mofetil for immunosuppression increases the adequacy of response. The antibody titers correlated positively with relative number of CD8+ cells and negatively with CD4/CD8 ratio in responders.

Assessment of humoral and cellular immunity induced by the BNT162b2 SARS-CoV-2 vaccine in healthcare workers, elderly people, and immunosuppressed patients with autoimmune disease

The development of vaccines to prevent SARS-CoV-2 infection has mainly relied on the induction of neutralizing antibodies (nAbs) to the Spike protein of SARS-CoV-2, but there is growing evidence that T cell immune response can contribute to protection as well. In this study, an anti-receptor binding domain (RBD) antibody assay and an INFγ-release assay (IGRA) were used to detect humoral and cellular responses to the Pfizer-BioNTech BNT162b2 vaccine in three separate cohorts of COVID-19-naïve patients: 108 healthcare workers (HCWs), 15 elderly people, and 5 autoimmune patients treated with immunosuppressive agents. After the second dose of vaccine, the mean values of anti-RBD antibodies (Abs) and INFγ were 123.33 U/mL (range 27.55-464) and 1513 mIU/mL (range 145-2500) in HCWs and 210.7 U/mL (range 3-500) and 1167 mIU/mL (range 83-2500) in elderly people. No correlations between age and immune status were observed. On the contrary, a weak but significant positive correlation was found between INFγ and anti-RBD Abs values (rho = 0.354, p = 0.003). As to the autoimmune cohort, anti-RBD Abs were not detected in the two patients with absent peripheral CD19+B cells, despite high INFγ levels being observed in all 5 patients after vaccination. Even though the clinical relevance of T cell response has not yet been established as a correlate of vaccine-induced protection, IGRA testing has showed optimal sensitivity and specificity to define vaccine responders, even in patients lacking a cognate antibody response to the vaccine.

Humoral response to BNT162b2 mRNA COVID-19 vaccine in peritoneal and hemodialysis patients: A comparative study

Introduction

Maintenance dialysis patients (MDP) are at higher risk of exposure with increased mortality from COVID‐19 with generalized immunization becoming the cornerstone in prevention. This study aims to compare humoral response between hemodialysis (HD) and peritoneal dialysis (PD) patients.

Materials and Methods

Observational prospective study following HD and PD programs from a Portuguese Center receiving BNT162b2 vaccine. Specific anti‐Spike IgG quantification to compare both for absolute value and non‐responders (NR) between modalities and against risk factors.

Results

Of 67 MDP, 42 were HD and 25 PD patients. PD developed higher antibody titers after both first (median 5.44 vs. 0.99 AU/ml, p < 0.01) and second dose (median 170.43 vs. 65.81 AU/ml; p < 0.01). HD associated with NR after the first dose (p < 0.01).

Conclusion

This study demonstrated improved humoral immunogenicity with BNT162b2 in PD compared to HD patients. These differences are attributed to comorbidity burden and age differences, rather than dialysis modality.

The Importance of RNA-Based Vaccines in the Fight against COVID-19: An Overview

In recent years, vaccine development using ribonucleic acid (RNA) has become the most promising and studied approach to produce safe and effective new vaccines, not only for prophylaxis but also as a treatment. The use of messenger RNA (mRNA) as an immunogenic has several advantages to vaccine development compared to other platforms, such as lower coast, the absence of cell cultures, and the possibility to combine different targets. During the COVID-19 pandemic, the use of mRNA as a vaccine became more relevant; two out of the four most widely applied vaccines against COVID-19 in the world are based on this platform. However, even though it presents advantages for vaccine application, mRNA technology faces several pivotal challenges to improve mRNA stability, delivery, and the potential to generate the related protein needed to induce a humoral- and T-cell-mediated immune response. The application of mRNA to vaccine development emerged as a powerful tool to fight against cancer and non-infectious and infectious diseases, for example, and represents a relevant research field for future decades. Based on these advantages, this review emphasizes mRNA and self-amplifying RNA (saRNA) for vaccine development, mainly to fight against COVID-19, together with the challenges related to this approach.

Immunogenicity Rates After SARS-CoV-2 Vaccination in People With End-stage Kidney Disease: A Systematic Review and Meta-analysis

Importance

Adults receiving dialysis treatment have a higher likelihood of death when infected with SARS-CoV-2 than adults not receiving dialysis treatment. To date, the immune response of people receiving dialysis after SARS-CoV-2 vaccination has not been systematically discussed.

Objective

To assess immunogenicity rates in people with end-stage kidney disease (ESKD) receiving SARS-CoV-2 vaccines, explore postvaccination potential risk factors for nonresponse, and assess whether receiving dialysis is associated with different antibody response rates compared with the nondialysis population.

Data Sources

This systematic review and meta-analysis used articles from PubMed, Medline, and Embase published before July 30, 2021, as well as articles in the medRxiv preprint server.

Study Selection

Studies that evaluated the immunogenicity rate according to the postvaccine antibody response rate in patients with ESKD receiving dialysis were selected.

Data Extraction and Synthesis

The meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. A random-effects model was used. Two independent reviewers conducted the literature search and extracted the data.

Main Outcomes and Measures

The primary outcome was the pooled antibody postvaccine response rates in individuals with ESKD. The secondary outcomes were pooled response rates in individuals receiving and not receiving dialysis. Subgroup analysis and meta-regression were conducted to identify the sources of heterogeneity.

Results

A total of 32 studies were included. The overall immunogenicity rate of the dialysis group was 86% (95% CI, 81%-89%). Meta-regression showed a significant difference was detected in the postvaccine response rate on the basis of prevalence of diabetes (regression coefficient, -0.06; 95% CI, -0.10 to -0.02; P = .004). Compared with nondialysis controls, patients in the dialysis group had a lower response rate after the first (relative risk [RR], 0.61; 95% CI, 0.47-0.79; I2 = 70.2%) and second (RR, 0.88; 95% CI, 0.82-0.93; I2 = 72.2%) doses, with statistically significantly increased RR between first and second doses (P = .007).

Conclusions and Relevance

These findings suggest that the immunogenicity rate among patients receiving dialysis was 41% after the first dose and 89% after the second dose. Diabetes might be a risk factor for nonresponse in the dialysis population. Patients receiving dialysis had a poorer antibody response rate than did individuals not receiving dialysis, particularly after the first dose.

Coronavirus disease 2019 and renal transplantation

Ever since the severe acute respiratory syndrome virus causing coronavirus disease 2019 (COVID-19) struck the world, global health strategies have changed significantly. According to the Centers for Disease Control and Prevention, kidney transplant recipients are stratified as being high risk of developing fatal illness from COVID-19 infection. Kidney transplant is the gold-standard treatment for end-stage kidney disease subjects. During the pandemic, significant concerns have emerged regarding continuation of kidney transplant surgeries and management of kidney transplant recipients post-transplant. The added risk of immunosuppression in this cohort was and remains a theoretical concern, posing a potential risk of transplantation rather than benefit. This comprehensive review aims to cover most of the faced challenges in kidney transplantation in different stages of the pandemic. In addition, it will elucidate the epidemiology, nature, course of the disease, surgical consideration in donors and recipients as well as role of immunosuppression and management of COVID-19 infected kidney transplant recipients during these extraordinary circumstances.

SARS-CoV-2 Antibody Response After a Third Dose of the BNT162b2 Vaccine in Patients Receiving Maintenance Hemodialysis or Peritoneal Dialysis

Rationale & Objective

Recent studies showed that antibody titers after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the dialysis population are diminished as compared with the general population, suggesting the possible value of a third booster dose. We characterized the humoral response after 3 doses of the BNT162b2 vaccine in patients treated with either maintenance hemodialysis (HD) or peritoneal dialysis (PD).

Study Design

Case series.

Setting & Participants

69 French patients (38 HD and 31 PD) treated at a single center who received 3 doses of the BNT162b2 vaccine.

Findings

Humoral response was evaluated using plasma levels of anti-SARS-CoV-2 spike protein S1 immunoglobulin measured after the second dose and at least 3 weeks after the third dose of the BNT162b2 vaccine. Patients (median age 68 years [interquartile range (IQR), 53-76 years], 65% men) had a median anti-S1 antibody level of 284 [IQR, 83-1190] AU/mL after the second dose, and 7,554 [IQR, 2,268-11,736] AU/mL after the third dose. Three patients were nonresponders (anti-S1 antibody level < 0.8 AU/mL), and 12 were weak responders (anti-S1 antibody level 0.8-50 AU/mL) after the second vaccine dose. After the third dose, 1 of the 3 initial nonresponders produced anti-spike antibody, and all the 12 initial weak responders increased their antibody levels. Patients with a greater increase in anti-S1 antibody levels after a third dose had lower antibody levels after the second dose, and a longer time interval between the second and the third dose. Adverse events did not seem to be more common or severe after a third vaccine dose.

Limitations

Observational study, small sample size. Relationship between antibody levels and clinical outcomes is not well understood.

Conclusions

A third dose of the BNT162b2 vaccine substantially increased antibody levels in patients receiving maintenance dialysis and appeared to be as well tolerated as a second dose.