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3.
Clin Infect Dis ; 2022 Aug 12.
Article in English | MEDLINE | ID: covidwho-1992159

ABSTRACT

Antibody responses to SARS-CoV-2 vaccination are reduced in solid organ transplant recipients (SOTRs). We report that increased levels of pre-existing antibodies to seasonal coronaviruses are associated with decreased antibody response to SARS-CoV-2 vaccination in SOTRs, supporting that antigenic imprinting modulates vaccine responses in this immunosuppressed population.

4.
Am J Transplant ; 2022 Jul 23.
Article in English | MEDLINE | ID: covidwho-1973539

ABSTRACT

A recent study concluded that SARS-CoV-2 mRNA vaccine responses were improved among transplant patients taking mTOR inhibitors (mTORi). This could have profound implications for vaccine strategies in transplant patients; however, limitations in the study design raise concerns about the conclusions. To address this issue more robustly, in a large cohort with appropriate adjustment for confounders, we conducted various regression- and machine learning-based analyses to compare antibody responses by immunosuppressive agents in a national cohort (n = 1037). MMF was associated with significantly lower odds of positive antibody response (aOR = 0.09 0.130.18 ). Consistent with the recent mTORi study, the odds tended to be higher with mTORi (aOR = 1.00 1.452.13 ); however, importantly, this seemingly protective tendency disappeared (aOR = 0.47 0.731.12 ) after adjusting for MMF. We repeated this comparison by combinations of immunosuppression agents. Compared to MMF + tacrolimus, MMF-free regimens were associated with higher odds of positive antibody response (aOR = 2.39 4.267.92 for mTORi+tacrolimus; 2.34 5.5415.32 for mTORi-only; and 6.78 10.2515.93 for tacrolimus-only), whereas MMF-including regimens were not, regardless of mTORi use (aOR = 0.81 1.542.98 for MMF + mTORi; and 0.81 1.512.87 for MMF-only). We repeated these analyses in an independent cohort (n = 512) and found similar results. Our study demonstrates that the recently reported findings were confounded by MMF, and that mTORi is not independently associated with improved vaccine responses.

5.
Transplantation ; 2022 Jul 21.
Article in English | MEDLINE | ID: covidwho-1948635

ABSTRACT

BACKGROUND: Solid organ transplant recipients (SOTRs) are less likely to mount an antibody response to SARS-CoV-2 mRNA vaccines. Understanding risk factors for impaired vaccine response can guide strategies for antibody testing and additional vaccine dose recommendations. METHODS: Using a nationwide observational cohort of 1031 SOTRs, we created a machine learning model to explore, identify, rank, and quantify the association of 19 clinical factors with antibody responses to 2 doses of SARS-CoV-2 mRNA vaccines. External validation of the model was performed using a cohort of 512 SOTRs at Houston Methodist Hospital. RESULTS: Mycophenolate mofetil use, a shorter time since transplant, and older age were the strongest predictors of a negative antibody response, collectively contributing to 76% of the model's prediction performance. Other clinical factors, including transplanted organ, vaccine type (mRNA-1273 versus BNT162b2), sex, race, and other immunosuppressants, showed comparatively weaker associations with an antibody response. This model showed moderate prediction performance, with an area under the receiver operating characteristic curve of 0.79 in our cohort and 0.67 in the external validation cohort. An online calculator based on our prediction model is available at http://transplantmodels.com/covidvaccine/. CONCLUSIONS: Our machine learning model helps understand which transplant patients need closer follow-up and additional doses of vaccine to achieve protective immunity. The online calculator based on this model can be incorporated into transplant providers' practice to facilitate patient-centric, precision risk stratification and inform vaccination strategies among SOTRs.

15.
Am J Gastroenterol ; 117(5): 798-801, 2022 05 01.
Article in English | MEDLINE | ID: covidwho-1835980

ABSTRACT

INTRODUCTION: The response to SARS-CoV-2 vaccination of patients with inflammatory bowel disease (IBD) on immune-modifying therapies requires further investigation because previous studies indicate that patients on immune therapy might have decreased antibody concentrations. METHODS: We present the antireceptor binding domain antibody response over a period of 3 months in 217 patients with IBD who completed standard 2-dose SARS-CoV-2 mRNA vaccine series. RESULTS: Almost all (98.6%) IBD vaccine recipients had a positive antireceptor binding domain antibody response at least 3 months after vaccination. Decreased antibody titers at 3 months were seen in a subset of patients on antitumor necrosis factor-alpha. Approximately 10% of the participants with high-titer antibodies at 1 month had a decrease to low-positive titers at 3 months, which was mostly observed in those on combination therapy and antitumor necrosis factor-alpha monotherapy. DISCUSSION: Larger longitudinal studies are required to define the response in IBD population and its clinical impact.


Subject(s)
COVID-19 , Inflammatory Bowel Diseases , Antibodies, Viral , Antibody Formation , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Inflammatory Bowel Diseases/drug therapy , Necrosis , RNA, Messenger , SARS-CoV-2 , Vaccination , Vaccines, Synthetic , mRNA Vaccines
16.
Am J Transplant ; 2022 Apr 16.
Article in English | MEDLINE | ID: covidwho-1831928

ABSTRACT

Heterologous vaccination ("mixing platforms") for the third (D3) dose of SARS-CoV-2 vaccine is a potential strategy to improve antibody responses in solid organ transplant recipients (SOTRs), but data are mixed regarding potential differential immunogenicity. We assessed for differences in immunogenicity and tolerability of homologous (BNT162b2 or mRNA-1273; D3-mRNA) versus heterologous (Ad.26.COV2.S; D3-JJ) D3 among 377 SARS-CoV-2-infection naïve SOTRs who remained seronegative after two mRNA vaccines. We measured anti-spike titers and used weighted Poisson regression to evaluate seroconversion and development of high-titers, comparing D3-JJ to D3-mRNA, at 1-, 3-, and 6 month post-D3. 1-month post-D3, seroconversion (63% vs. 52%, p = .3) and development of high-titers (29% vs. 25%, p = .7) were comparable between D3-JJ and D3-mRNA recipients. 3 month post-D3, D3-JJ recipients were 1.4-fold more likely to seroconvert (80% vs. 57%, weighted incidence-rate-ratio: wIRR = 1.10 1.401.77 , p = .006) but not more likely to develop high-titers (27% vs. 22%, wIRR = 0.44 0.921.93 , p = .8). 6 month post-D3, D3-JJ recipients were 1.41-fold more likely to seroconvert (88% vs. 59%, wIRR = 1.04 1.411.93 , p = .029) and 2.63-fold more likely to develop high-titers (59% vs. 21%, wIRR = 1.38 2.635.00 , p = .003). There was no differential signal in alloimmune events or reactogenicity between platforms. SOTRs without antibody response after two mRNA vaccines may derive benefit from heterologous Ad.26.COV2.S D3.

18.
Transplant Direct ; 6(7): e572, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-1794966

ABSTRACT

BACKGROUND: The early effects of coronavirus disease 2019 (COVID-19) on transplantation are dramatic: >75% of kidney and liver programs are either suspended or operating under major restrictions. To resume transplantation, it is important to understand the prevalence of COVID-19 among transplant recipients, donors, and healthcare workers (HCWs) and its associated mortality. METHODS: To investigate this, we studied severe acute respiratory syndrome coronavirus 2 diagnostic test results among patients with end-stage renal disease or kidney transplants from the Johns Hopkins Health System (n = 235), and screening test results from deceased donors from the Southwest Transplant Alliance Organ Procurement Organization (n = 27), and donors, candidates, and HCWs from the National Kidney Registry and Viracor-Eurofins (n = 253) between February 23 and April 15, 2020. RESULTS: We found low rates of COVID-19 among donors and HCWs (0%-1%) who were screened, higher rates of diagnostic tests among patients with end-stage renal disease or kidney transplant (17%-20%), and considerable mortality (7%-13%) among those who tested positive. CONCLUSIONS: These findings suggest the threat of COVID-19 for the transplant population is significant and ongoing data collection and reporting is critical to inform transplant practices during and after the pandemic.

20.
Transplantation ; 106(7): 1440-1444, 2022 07 01.
Article in English | MEDLINE | ID: covidwho-1788574

ABSTRACT

BACKGROUND: Humoral responses to coronavirus disease 2019 (COVID-19) vaccines are attenuated in solid organ transplant recipients (SOTRs), necessitating additional booster vaccinations. The Omicron variant demonstrates substantial immune evasion, and it is unknown whether additional vaccine doses increase neutralizing capacity versus this variant of concern (VOC) among SOTRs. METHODS: Within an observational cohort, 25 SOTRs with low seroresponse underwent anti-severe acute respiratory syndrome coronavirus 2 spike and receptor-binding domain immunoglobulin (Ig)G testing using a commercially available multiplex ELISA before and after a fourth COVID-19 vaccine dose (D4). Surrogate neutralization (percent angiotensin-converting enzyme 2 inhibition [%ACE2i], range 0%-100% with >20% correlating with live virus neutralization) was measured against full-length spike proteins of the vaccine strain and 5 VOCs including Delta and Omicron. Changes in IgG level and %ACE2i were compared using the paired Wilcoxon signed-rank test. RESULTS: Anti-receptor-binding domain and anti-spike seropositivity increased post-D4 from 56% to 84% and 68% to 88%, respectively. Median (interquartile range) anti-spike antibody significantly increased post-D4 from 42.3 (4.9-134.2) to 228.9 (1115.4-655.8) World Health Organization binding antibody units. %ACE2i (median [interquartile range]) also significantly increased against the vaccine strain (5.8% [0%-16.8%] to 20.6% [5.8%-45.9%]) and the Delta variant (9.1% [4.9%-12.8%] to 17.1% [10.3%-31.7%]), yet neutralization versus Omicron was poor, did not increase post-D4 (4.1% [0%-6.9%] to 0.5% [0%-5.7%]), and was significantly lower than boosted healthy controls. CONCLUSIONS: Although a fourth vaccine dose increases anti-spike IgG and neutralizing capacity against many VOCs, some SOTRs may remain at high risk for Omicron infection despite boosting. Thus, additional protective interventions or alternative vaccination strategies should be urgently explored.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Transplant Recipients , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Humans , Immunoglobulin G/blood , SARS-CoV-2
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