key: cord-1028625-ttsqu63v
authors: Ruether, Darius F.; Schaub, Golda M.; Duengelhoef, Paul M.; Haag, Friedrich; Brehm, Thomas T.; Fathi, Anahita; Wehmeyer, Malte; Jahnke-Triankowski, Jacqueline; Mayer, Leonie; Hoffmann, Armin; Fischer, Lutz; Addo, Marylyn M.; Lütgehetmann, Marc; Lohse, Ansgar W.; Schulze zur Wiesch, Julian; Sterneck, Martina
title: SARS-CoV2-specific humoral and T-cell immune response after second vaccination in liver cirrhosis and transplant patients
date: 2021-09-09
journal: Clin Gastroenterol Hepatol
DOI: 10.1016/j.cgh.2021.09.003
sha: abd18954b91c459d56c5079340058e7ed68ca0bd
doc_id: 1028625
cord_uid: ttsqu63v

Background and Aims Detailed information on the immune response after second vaccination of cirrhotic patients and liver transplant (LT) recipients against SARS-CoV-2 is largely missing. We aimed at comparing the vaccine-induced humoral and T-cell responses of these vulnerable patient groups. Methods In this prospective cohort study, anti-SARS-CoV-2 spike-protein titers were determined using the DiaSorin LIAISON (anti-S Trimer) and Roche Elecsys (anti-S RBD) immunoassays in 194 patients (141 LT, 53 cirrhosis Child-Pugh A-C) and 56 healthy controls before and 10-84 days after second vaccination. The spike-specific T-cell response was assessed using an IFN-γ release assay (IGRA, EUROIMMUN). A logistic regression analysis was performed to identify predictors of low response. Results After the second vaccination, seroconversion was achieved in 63% of LT recipients and 100% of cirrhotic patients and controls using the anti-S Trimer assay. Median anti-SARS-CoV-2 titers of responding LT recipients were lower compared to cirrhotic patients and controls (p<0.001). Spike-specific T-cell response rates were 36.6%, 65.4%, and 100% in LT, cirrhosis, and controls, respectively. Altogether, 28% of LT recipients did neither develop a humoral nor a T-cell response after second vaccination. In LT recipients, significant predictors of absent or low humoral response were age >65y (OR: 4.57, 95%-CI 1.48-14.05) and arterial hypertension (OR: 2.50, 95%-CI 1.10-5.68), whereas vaccination failure was less likely with calcineurin inhibitor monotherapy than with other immunosuppressive regimens (OR: 0.36, 95%-CI 0.13-0.99). Conclusion Routine serological testing of the vaccination response and a third vaccination in patients with low or absent response seem advisable. These vulnerable cohorts need further research on the effects of heterologous vaccination and intermittent reduction of immunosuppression before booster vaccinations.

However, markedly increased mortality due to COVID-19 has been described for both 114 patient groups compared to the healthy population indicating the need for SARS-CoV-115 2 vaccination. 3, 4 116 Preliminary data showed that LT recipients might be less likely to reach seroconversion 117 after SARS-CoV-2 vaccination, 5, 6 but up to now few detailed data are available on 118 patients with cirrhosis. Also, individual risk factors for an inadequate vaccination 119 response have not been studied comprehensively in these populations so far. An 120 ongoing trial found an overall seroconversion rate of 89% in immunocompromised 121 patients and the highest risk of non-seroconversion in patients with vasculitis and B-122 cell depletion. 7 123

This prospective observational study explores the humoral and T-cell response to 124 SARS-CoV-2 vaccination in a large cohort of patients with compensated and 125 decompensated liver cirrhosis and LT recipients. Also, predictors of low response to 126 vaccination were identified in this highly vulnerable patient population. 127 J o u r n a l P r e -p r o o f

Non-pregnant patients ≥18 years with liver cirrhosis presenting for liver transplantation 130 or patients post LT were enrolled in this prospective observational cohort study at the 131 University Medical Center Hamburg-Eppendorf (UKE) in case of SARS-CoV-2 132 vaccination with a two-dose regimen, consisting of an mRNA (BNT162b2; BioNTech 133 SE / Pfizer or mRNA-1273; Moderna Biotech) or vector-based vaccine (AZD1222; 134 AstraZeneca). LT recipients receiving a combined transplantation and cirrhotic patients 135 under immunosuppression were excluded. Clinical data were obtained from the 136 patients' electronic medical records. In addition, control subjects matched by age and 137 vaccination regimen were included. In all participants, the immune response was 138 determined 10-84 days after the second vaccination, and in a subgroup also directly 139 before the first and second vaccination. The study was approved by the local Ethics 140

Committee of Hamburg, Germany (Reg. number PV7103) and the Paul Ehrlich 141

Institute, the German Federal Institute for Vaccines and Biomedicines (Reg. number 142 NIS508). All participants signed written informed consent and all authors had access 143 to the study data and reviewed and approved the final manuscript. 144 145

The vaccine-specific humoral immune response was quantitatively determined by two 147 different anti-SARS-CoV-2 spike immunoassays in parallel: The DiaSorin LIAISON XL 148 anti-SARS-CoV-2 TrimericS IgG ChemiLuminescent ImmunoAssay (CLIA, sensitivity 149 99.4%, specificity 99.8%, cut-off 33.8 BAU/mL 8 ), with spike S1 glycoproteins 150 assembled as trimers allowing to detect a broad range of antibodies including 151 responses to the N terminal regions of the spike protein (anti-S Trimer) and the Roche 152

Elecsys anti-SARS-CoV-2 S Ig ElectroChemiLuminescent ImmunoAssay (ECLIA, 153 J o u r n a l P r e -p r o o f sensitivity 93.9%, specificity 99.6%, cut-off 0.8 U/mL 9 ) with a receptor-binding domain 154 protein (RBD) sandwich assay design (anti-S RBD). For both assays, a low positive 155 response was defined from 33.8 to 100 BAU/mL and from 0.8 to 100 U/mL, 156 respectively, based on thresholds of validating studies and on cut-offs used in 157 randomized trials. 10, 11 158

The SARS-CoV-2 spike protein-specific T-cell response was determined by a 159 commercial, standardized Interferon-gamma (IFN-) release assay (IGRA) using the 160 EUROIMMUN SARS-CoV-2 IGRA stimulation tube set (product No. ET 2606-3003) J o u r n a l P r e -p r o o f

Altogether 194 patients (53 cirrhotic patients with Child-Pugh class A to C and 141 LT 186 recipients) and 56 controls were enrolled in this study (Figure 1) . Nine convalescents 187 recovered from COVID-19 (2 LC, 3 LT) were analyzed separately. 188

Characteristics of patients and controls included in the main analysis are shown in 189 Figures 1 and 2 ) did not differ between the groups. 203 204

After the second vaccination (median 29 days), significantly fewer LT recipients tested 206 positive for anti-SARS-CoV-2 Ig compared to cirrhotic patients and controls using the 207 anti-S RBD (73.9% vs. 100% vs. 100%, respectively) or the anti-S Trimer assay (63.0% 208 vs. 97.9% vs. 100%, respectively). A negative or weak anti-SARS-CoV-2 response 209 was seen in 2% (anti-S RBD) and 6% (anti-S Trimer) of the cirrhotic patients and 46% 210 (anti-S RBD) and 48% (anti-S Trimer) of the LT recipients, respectively ( Figure 2D-F) . 211 Furthermore, the median titers of anti-SARS-CoV-2 Ig were significantly lower in 212 patients post LT as compared to patients with liver cirrhosis (Figure 2A-C) . Thus, in 213 contrast to LT recipients, cirrhotic patients were not found to have an impaired humoral 214 immune response compared to controls based concerning seroconversion rate and 215 median antibody titers of responding patients (Supplementary Table 1) . 216

Of note, there was a high concordance between both immunoassays (Supplementary 217 

The anti-SARS-CoV-2 Ig titers after the first and second vaccination (19 LC, 88 LT) 223 are shown in Supplementary Figures 4A and B . The seroconversion rate markedly 224 increased in cirrhotic patients (from 77.8% to 100%) and LT recipients (15.4% to 225 55.4%). In patients who did not develop a detectable humoral response after the first 226 vaccination, the probability of seroconversion after the second vaccination was 100% 227 for cirrhotic patients and 43.6% for LT recipients. Also, there was a significant 28-and 228 19-fold increase of the median anti-SARS-CoV-2 Ig titers in cirrhotic patients and LT 229 recipients, respectively at last follow-up 5 ± 3 weeks after vaccination. 230

The cellular immune response assessed by semiquantitative analysis of IFN- release 233 after spike-specific stimulation of T-cells was determined in a subgroup of 26 cirrhotic 234 patients, 82 LT recipients, and 19 controls. Overall, after the second vaccination, a T-235 cell response (cut-off >100 mIU/mL) was less frequently detectable in LT recipients 236 (37%) and cirrhotic patients (65%) compared to controls (100%) ( Figure 2F ). Only 32% 237 of LT recipients and 46% of cirrhotic patients showed a strong response (cut-off >200 238 mIU/mL) as compared to 100% of controls. Also, the median concentration of IFN- 239 release was significantly lower in patients with cirrhosis and LT recipients compared to 240 controls ( Figure 

Parameters investigated by univariate and multivariate binary logistic regression 255 analysis as potential predictors for a low immune response after the second SARS-256

CoV-2 vaccination in LT recipients are given in Table 2 (and Supplementary Table  257 2). Independent prognostic factors for no or only a weak antibody response were age 258 >65y (OR: 4.57, 95%-CI 1.48-14.05) and arterial hypertension (OR: 2.50, 95%-CI 1.10-259 5.68), while calcineurin inhibitor monotherapy was a positive prognostic factor for a 260 response as compared to other immunosuppressive regimens (OR: 0.36, 95%-CI 0.13-261 0.99) (Figure 3 ). In the LT cohort, e.g. only 19.2% of patients >65 y, but 59.6% of 262 patients <65 y attained anti-S Trimer titers above 100 BAU/mL (Supplementary Table  263 3). Of note, laboratory values were not considered for multivariate analysis because of 264 limited baseline values (n=42). However, the seroconversion rate (31.6% vs. 60.6%; 265 p=0.044) and median antibody titers (p=0.039) significantly differed between LT 266 recipients with B-lymphocytes below and above the reference value (80/µl) (Figure 267 respectively. Compared to LT recipients, higher antibody titers were found in both 285 patients with compensated (Child-Pugh class A) and decompensated liver cirrhosis 286 (Child-Pugh class B and C). Also, no differences in the antibody titers were found in 287 the subgroup of cirrhotic patients after TIPS implantation (n=9, 18.9%) compared to 288 patients without TIPS (Supplementary Table 6 In this study we used two different immunoassays to determine the humoral immune 308 response: The more commonly used anti-S RBD assay (Roche Elecsys) and the 309 anti-S Trimer assay (DiaSorin LIAISON). The latter assay was previously shown to 310 correlate highly with the current gold standard for detection of neutralizing antibodies. 8 311

Here, both assays showed a very high correlation in patients and controls (r=0.94). 312

In addition, we also evaluated the T-cell immune response by assessing the ex vivo 314 IFN- release after spike-specific stimulation of T-cells in a commercial, standardized 315 IGRA assay. It has been suggested that the vaccine-induced T-cell response may have 316 a protective effect even in the absence of a detectable vaccine-induced B-cell 317 response by limiting the extent of viral replication and by supporting long-term 318 immunological memory. 13 Therefore, solid organ transplant (SOT) recipients with a 319

strong T-cell response may be protected against a severe course of SARS-CoV-2 320 infection even in the absence of a seroconversion. 14 Our results demonstrate a spike-321 specific T-cell response only in around a fifth (22%) of LT recipients without 322 seroconversion, being in line with previously reported results in cardiothoracic (20%), 323 and kidney transplant recipients (29.8%). 15, 16 Furthermore, in 54% of the patients with 324 liver cirrhosis who attained seroconversion, the IFN- release in the IGRA was below 325 the cut-off. Whether this correlates with a lower protection against COVID-19 disease 326 has to be further investigated in larger prospective studies. vaccination. 17 In our cohort, we confirmed older age and low eGFR as predictors for a 334 low or negative humoral immune response. Additionally, a pre-vaccination B-335 lymphocyte count below the reference value of 80µl was a negative predictive factor, 336 while CNI monotherapy was a predictor for a positive humoral response. In principle, 337 our results are in line with those of Rabinowich et al. revealing that higher 338 immunosuppression reduces the response to vaccination 6 and adds to the knowledge 339 that LT recipients with low B-lymphocytes and arterial hypertension are at increased 340 risk of failure to SARS-CoV-2 vaccination. 341

In our small group of LT recipients who received prime AZD1222 and second mRNA 342 vaccination (n=11), a seroconversion rate of 81.8% and high titers were found. This 343 extends the recently published data describing significantly higher titers of neutralizing 344 antibodies after heterologous vaccination to this highly vulnerable population. 16 New 345 approaches to improve the immune response of LT recipients are urgently needed 346 since breakthrough infections have been reported to occur more frequently in SOT 347 recipients than in the healthy population. 18 Although recently a randomized trial found 348 significantly higher antibody titers in this population after a third homologous 349 vaccination, the seroconversion rate remained low with only 50% of previously 350 nonresponsive SOT recipients attaining anti-S RBD titer ≥100 U/mL. 11 In comparison to previous studies 5, 6 this study included different vaccination regimens, 366 measured immune response in more detail, and investigated also pre-transplant 367 patients with decompensated cirrhosis. 368

Nonetheless, the study is not without limitations. Firstly, due to the study design, the 369 time interval between the second vaccination and blood sample varied between 10 to 370 84 days in patients and was longer in controls. However, the data presented here and 371 those of previous studies of our group 23 did not show a significant increase or decrease 372 of antibody titers over the defined inclusion period (Supplementary Figure 8) . Correlation between humoral and T-cell immune response for cirrhotic patients (green ascending triangles), LT recipients (red descending triangles) and controls (blue dots). Background: After vaccination against SARS-CoV-2 the immune response is reduced in organ transplant recipients as compared to the healthy population.

Findings: Older age, arterial hypertension and immunosuppression other than calcineurin inhibitor monotherapy predict vaccination failure in liver transplant recipients. In decompensated liver cirrhosis patients, the humoral immune response is comparable to healthy controls.

Implications for patient care: Identification of predictors of no or low immune response after initial vaccinations will help to decide on further booster strategies.

Patients with liver cirrhosis should be vaccinated pre transplantation.

Efficacy and Safety of the mRNA-1273

SARS-CoV-2 Vaccine

Safety and Efficacy of the BNT162b2

mRNA Covid-19 Vaccine

Outcomes following SARS-CoV-2 infection 431 in patients with chronic liver disease: An international registry study

Outcomes following SARS-CoV-2 infection 434 in liver transplant recipients: an international registry study

Antibody Response to 2-Dose SARS-437

CoV-2 mRNA Vaccine Series in Solid Organ Transplant Recipients

Low immunogenicity to SARS-CoV-440 2 vaccination among liver transplant recipients

Examining the Immunological Effects 442 of COVID-19 Vaccination in Patients with Conditions Potentially Leading to Diminished 443

Immune Response Capacity -The OCTAVE Trial

SARS-CoV-2 TrimericS IgG assay for the detection of circulating antibodies

Comparative Performance of Five 449

Neutralizing antibody levels are highly 465 predictive of immune protection from symptomatic SARS-CoV-2 infection

Poor humoral and T-cell 468 response to two-dose SARS-CoV-2 messenger RNA vaccine BNT162b2 in 469 cardiothoracic transplant recipients

Immunogenicity and reactogenicity of 471

heterologous ChAdOx1 nCoV-19/mRNA vaccination. Nature medicine

Humoral and T-cell responses to 474

SARS-CoV-2 vaccination in patients receiving immunosuppression

Rheumatic Diseases