Development and longevity of antibodies against SARS-CoV-2 in kidney transplant recipients after symptomatic COVID-19

Evaluation of the Humoral and Cellular Immune Response Post COVID-19 Infection in Kidney Transplant Recipients

Kidney transplantation is a major risk factor for severe forms of coronavirus disease 2019 (COVID-19). The dynamics and the persistence of the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in this immunocompromised population remain largely unknown. This study aimed to evaluate the persistence of humoral and cellular immune response in kidney transplant recipients (KTRs) and to establish whether immunosuppressive therapy influenced long-term immunity in this population. We report here the analysis of anti-SARS-CoV-2 antibodies and T cell-mediated immune responses in 36 KTRs compared to a control group who recovered from mild COVID-19. After a mean time of 5.22 ± 0.96 months post symptom onset for kidney transplant recipients, 97.22% of patients and 100% of the control group displayed anti-S1 immunoglobulin G SARS-CoV-2 antibodies (p > 0.05). No significant difference was reported in the median of neutralizing antibodies between the groups (97.50 [55.25-99] in KTRs vs. 84 [60-98] in control group, p = 0.35). A significant difference in SARS-CoV-2-specific T cell reactivity was found in the KTRs compared to the healthy controls. The levels of IFNγ release after stimulation by Ag1, Ag2 and Ag3 were higher in the control group compared to the kidney transplant group (p = 0.007, p = 0.025 and p = 0.008, respectively). No statistically significant correlation between humoral and cellular immunity was found in the KTRs. Our findings indicated that humoral immunity persisted similarly for up to 4 to 6 months post symptom onset in both the KTRs and the control group; however, T cell response was significantly higher in the healthy population compared to the immunocompromised patients.

Antibody Response to ChAdOx1 nCoV-19 (AZD1222) Vaccine in Kidney Transplant Recipients

Kidney transplant recipients (KTRs) are at a much higher risk of complications and death following COVID-19 and are poor vaccine responders. The data are limited on the immune response to Covishield® in KTRs. We prospectively recruited a cohort of 67 KTRs aged >18 between April 2021 and December 2021. Each participant was given two intramuscular doses of Covishield®, each of 0.5 mL, at an interval of 12 weeks. A blood specimen of 5.0 mL was collected from each participant at two points within a few days before administering the first dose of the vaccine and at any time between 4−12 weeks after administering the second dose. The sera were tested for anti-RBD antibody (ARAb) titre and neutralising antibody (NAb). An ACE2 competition assay was used as a proxy for virus neutralization. According to the prior COVID-19 infection, participants were grouped as (i) group A: prior symptomatic COVID-19 infection, (ii) group B: prior asymptomatic COVID-19 infection as evidenced by detectable ARAb in the prevaccination specimen, (iii) Group C: no prior infection with COVID-19, (iv) group D: Unclassified, i.e., participants had no symptoms suggestive of COVID-19, but their prevaccination specimen was not available for ARAb testing before vaccination. Fifty of sixty-seven participants (74.6%) provided paired specimens (group A 14, group B 27, and group C 9) and 17 participants (25.4%) provided only postvaccination specimens (group D). In the overall cohort (n = 67), 91% and 77.6% of participants developed ARAb and NAb, respectively. Their ARAb titre and NAb proportion were 2927 (520−7124) U/mL and 87.9 (24.4−93.2) %, respectively. Their median ARAb titre increased 65.6 folds, from 38.2 U/mL to 3137 U/mL. Similarly, the proportion of participants with NAb increased from 56% to 86%, and the NAb proportion raised 2.7 folds, from 23% to 91%. A comparison of vaccine response between the study groups showed that all those with or without prior COVID-19 infection showed a significant rise in ARAb titre (p < 0.05) and NAb proportion (p < 0.05) after the two doses of vaccine administration. The median value of folds rise in anti-RBD and NAb between groups A and B were comparable. Hence, ARAb is present in more than 3/4th of KTRs before the ChAdOx1 vaccine in India. The titer of ARAb and the proportion of NAb significantly increased after the two doses of the ChAdOx1 vaccine in KTRs.

COVID-19 and kidney disease: insights from epidemiology to inform clinical practice

Over the course of the COVID-19 pandemic, numerous studies have aimed to address the challenges faced by patients with kidney disease and their caregivers. These studies addressed areas of concern such as the high infection and mortality risk of patients on in-centre haemodialysis and transplant recipients. However, the ability to draw meaningful conclusions from these studies has in some instances been challenging, owing to barriers in aspects of usual care, data limitations and problematic methodological practices. In many settings, access to SARS-CoV-2 testing differed substantially between patient groups, whereas the incidence of SARS-CoV-2 infection varied over time and place because of differences in viral prevalence, targeted public health policies and vaccination rates. The absence of baseline kidney function data posed problems in the classification of chronic kidney disease and acute kidney injury in some studies, potentially compromising the generalizability of findings. Study findings also require attentive appraisal in terms of the effects of confounding, collider bias and chance. As this pandemic continues and in the future, the implementation of sustainable and integrated research infrastructure is needed in settings across the world to minimize infection transmission and both prevent and plan for the short-term and long-term complications of infectious diseases. Registries can support the real-world evaluation of vaccines and therapies in patients with advanced kidney disease while enabling monitoring of rare complications.

A Narrative Review COVID-19 in Solid-Organ Transplantation: Real-World Evidence From India

Worldwide, India ranks number 2 and 3 for COVID-19 burden and absolute transplant numbers, respectively. Here, we summarized our single and multicenter Indian studies on solid-organ transplant during the COVID-19 pandemic. During the pandemic, solid-organ transplants declined 40% to 50%. The mortality rate in COVID-19-positive kidney transplant recipients (11.6%) was lower in India compared with the developed world during the first wave and lower compared with maintenance hemodialysis patients (13% to 38%) but significantly higher compared with the nonimmunosuppressed general population (1% to 3%) in India. We contributed to National Organ and Tissue Transplant Organization transplant-related guidelines to increase safety and access to solid-organ transplant. We reported the safety and feasibility of remdesivir (n = 57) and convalescent plasma therapy (n = 10) in kidney transplant recipients. We reported 100% patient and graft survival without any complications related to COVID-19 in a large cohort of kidney transplant recipients who recovered from COVID-19 (n = 372) and a large cohort of kidney transplant recipients of living donors (n = 31) who recovered from COVID-19 without any change in induction and maintenance immunosuppression. COVID-19 disease severity and mortality in the second episode (reoccurring infection) was higher (46%) compared with the first episode (11.6%). There was 4.4% incidence of COVID-19-associated mucormycosis in kidney transplant recipients with mortality of 46% in the second wave. We reported COVID-19 vaccine safety with suboptimal efficacy in kidney transplant recipients and dialysis patients compared with the general population. Our report suggested that transplant with carefully selected COVID-19-recovered donors and patients may be feasible and safe, at least over the short term. Continued research is needed on vaccine efficacy, booster doses, and long-term follow up sequelae.

COVID-19 and Kidney Transplantation: Epidemiology, Histopathological Presentation, Clinical Presentation and Outcomes, and Therapeutic Strategies

Multiple case series of kidney transplant recipients with COVID-19 have shown increased mortality compared to nontransplant patients. To date, we do not have high-level evidence to inform immunosuppression minimization strategies in infected transplant recipients. Most centers, however, have adopted an early antimetabolite withdrawal in addition to other interventions. The epidemiological problem concerns also dialysis patients and waitlisted patients who have a higher COVID-19 infection diffusion with respect to kidney transplant recipients. Several factors influence mortality among kidney transplant recipients. Among these factors are the age, race, and comorbidity factors, such as hypertension, diabetes mellitus, obesity, and previous respiratory problems. Treatment is still limited. The only effective antiviral drug is remdesivir that should be administered before the development of the cytokine storm. Vaccination seems to be useful, but due to the concomitant immunosuppression limiting its efficacy, at least three or four doses should be administered.

Post vaccination analysis of anti-spike antibody responses in kidney transplant recipients with and without COVID-19 infection in a tertiary care center, India

Background

To investigate the anti-spike antibody response to vaccination in Kidney transplant recipients (KTRs) previously infected with SARS-CoV-2 as compared to KTRs with no history of COVID-19 from India.

Methods

SARS-CoV-2 spike immunoglobulin (Ig) G antibody response was measured in 105 post COVID-19 KTRs with PCR confirmed SARS-CoV-2 infection who received either no vaccination (cohort 1), single (cohort 2) or two doses (cohort 3) of vaccine and compared to 103 two-dose vaccinated COVID-19 naïve KTRs with no history of COVID-19 (cohort 4).

Results

Out of 103 COVID-19 naïve two-dose vaccinated KTRs, less than 50% became seropositive with anti-spike antibody titres &gt; 50AU/mL subsequent to complete vaccination, the seroconversion rate being comparable in subjects receiving CovishieldTM versus CovaxinTM vaccines. However, the seropositive KTRs vaccinated with CovishieldTM had higher anti-spike antibody titres as compared to those who received CovaxinTM. We observed higher anti-SARS-CoV-2 spike antibody levels in post COVID-19 KTRs after 1 dose of vaccine as compared with COVID-19 naïve two-dose vaccinated KTRs. Importantly, the second dose in post COVID-19 KTRs did not significantly increase anti-spike antibody levels compared with the single dose recipients.

Conclusions

Our data presents that in KTRs with previous SARS-CoV-2 infection a single dose of vaccine (CovishieldTM) may be effective in mounting optimal immune response. In contrast, COVID-19 naïve two-dose vaccinated KTRs respond poorly (&lt;50%) to current recommendation of a two-dose regimen in India.

COVID-19 Pandemic Research Opportunities in India: What the Pandemic Is Teaching Us About Transplantation

Coronavirus disease (COVID-19) has engulfed the whole world, and India has been the second worst-hit nation. Organ transplant services were halted in both the public and private care sectors of India, with public care sectors more adversely affected. Deceased donations were disproportionately more affected, with unfavorable rates at the peak of the pandemic. Mortality outcomes of COVID-19 among different organ transplant recipients in India have been lower compared with the Western world, with younger age and less comorbidities among Indian populations partly responsible for the lower mortality. Mortality and graft loss were mostly associated with older age and those with chronic graft dysfunction. During the pandemic, invasive fungal infections, like mucormycosis, have been reported, illustrating the need for multidisciplinary management. The Indian transplant societies have formulated and timely revised guidelines for transplantation in the COVID-19 era. Living donor transplants (both liver and kidney) after recovery from COVID-19 were both first described in India, providing a guiding tool for the world. Follow-up reports of recovered solid-organ transplant recipients have also been reported in Indian studies, showing reassuring long-term outcomes. Data of breakthrough COVID-19 cases after vaccination among both transplant recipients and waitlist candidates and research in vaccine efficacy for solid-organ transplant recipients is still underway. We suggest continuing and intensifying research activities for a better plan and strategy in case of a future pandemic.