INTRODUCTION: Patients with inflammatory bowel disease (IBD) on immune-modifying therapies may have a lower vaccine response to certain vaccines. The aim of our study was to evaluate humoral immunogenicity of mRNA coronavirus disease 2019 (COVID-19) vaccines among patients with IBD and healthy controls (HCs). METHODS: We performed a prospective study to evaluate humoral immunogenicity among patients with IBD and HCs after completion of mRNA COVID-19 vaccines. RESULTS: One hundred twenty-two patients with IBD and 60 HCs were enrolled. All HCs and 97% of patients with IBD developed antibodies. Antibody concentrations were lower in patients with IBD compared with those in HCs (median 31 vs 118 μg/mL; P < 0.001). Those who received the mRNA-1273 (Moderna) COVID-19 (median 38; interquartile range [IQR] 24–75 vs μg/mL) had higher antibody concentrations compared with those who received the Pfizer-BNT vaccine series (median 22; IQR 11–42 μg/mL; P < 0.001). Patients on immune-modifying therapy (median 26; IQR 13–50 μg/mL) had lower antibody concentrations compared with those who were on no treatment, aminosalicylates, or vedolizumab (median 59; IQR 31–75 μg/mL; P = 0.003). DISCUSSION: Almost all patients with IBD in our study mounted an antibody response. Future studies are needed in evaluating sustained humoral immunity and the impact of booster dosing in patients with IBD.

Background Patients with inflammatory bowel disease (IBD) on anti-tumor necrosis factor alpha (TNF) agents may have lower immune response to the influenza vaccine. We aimed to evaluate the immunogenicity of the high dose (HD) vs standard dose (SD) influenza vaccine in patients with IBD on anti-TNF monotherapy. Methods We performed a randomized clinical trial at a single academic center evaluating the immunogenicity of the HD vs SD influenza vaccine in patients with IBD on anti-TNF monotherapy. Influenza antibody concentration was measured at immunization, at 2 to 4 weeks postimmunization, and at 6 months. Results Sixty-nine patients with IBD were recruited into the study, 40 on anti-TNF monotherapy, and 19 on vedolizumab, along with 20 healthy controls (HC). Patients with IBD receiving the HD influenza vaccine had significantly higher H3N2 postimmunization antibodies compared with those who received the SD influenza vaccine (160 [interquartile range 80 to 320] vs 80 [interquartile range 40 to 160]; P = 0.003). The H1N1 postimmunization levels were not significantly higher in the HD influenza vaccine (320 [interquartile range 150 to 320] vs 160 [interquartile range 80 to 320]; P = 0.18). Patients with IBD receiving the HD influenza vaccine and those on vedolizumab who received SD had equivalent antibody concentrations to HC (H1N1 P = 0.85; H3N2 P = 0.23; B/Victoria P = 0.20 and H1N1 P = 0.46; H3N2 P = 0.21; B/Victoria P = 1.00, respectively). Conclusions Patients with IBD on anti-TNF monotherapy receiving the HD influenza vaccine had significantly higher postimmunization antibody levels compared with SD vaccine. Clinicaltrials.gov (#NCT02461758).

Microsatellite instability (MSI) occurs in over 90% of Lynch syndrome cancers and is considered a hallmark of the disease. MSI is an early event in colon tumor development, but screening polyps for MSI remains controversial because of reduced sensitivity compared to more advanced neoplasms. To increase sensitivity, we investigated the use of a novel type of marker consisting of long mononucleotide repeat (LMR) tracts. Adenomas from 160 patients, ranging in age from 29–55 years old, were screened for MSI using the new markers and compared with current marker panels and immunohistochemistry standards. Overall, 15 tumors were scored as MSI-High using the LMRs compared to 9 for the NCI panel and 8 for the MSI Analysis System (Promega). This difference represents at least a 1.7-fold increase in detection of MSI-High lesions over currently available markers. Moreover, the number of MSI-positive markers per sample and the size of allelic changes were significantly greater with the LMRs (p = 0.001), which increased confidence in MSI classification. The overall sensitivity and specificity of the LMR panel for detection of mismatch repair deficient lesions were 100% and 96%, respectively. In comparison, the sensitivity and specificity of the MSI Analysis System were 67% and 100%; and for the NCI panel, 75% and 97%. The difference in sensitivity between the LMR panel and the other panels was statistically significant (p<0.001). The increased sensitivity for detection of MSI-High phenotype in early colorectal lesions with the new LMR markers indicates that MSI screening for the early detection of Lynch syndrome might be feasible.

Lay Summary Herein, we evaluated the humoral immunogenicity of a third coronavirus disease 2019 messenger RNA vaccine dose in patients with inflammatory bowel diseases. All patients displayed a humoral immune response, and median antibody concentrations were higher after the third dose than after completion of the 2-dose series.

Summary: Herein, we evaluated the humoral immunogenicity of a third COVID-19 mRNA vaccine dose in patients with IBD. All patients were seropositive and had higher antibody concentrations after the third dose than after completion of the two-dose primary series.