Faculty Bibliography

Loss of Paneth cells and their antimicrobial granules compromises the intestinal epithelial barrier and is associated with Crohn's disease, a major type of inflammatory bowel disease^1-7. Non-classical lymphoid cells, broadly referred to as intraepithelial lymphocytes (IELs), intercalate the intestinal epithelium^8,9. This anatomical position has implicated them as first-line defenders in resistance to infections, but their role in inflammatory disease pathogenesis requires clarification. The identification of mediators that coordinate crosstalk between specific IEL and epithelial subsets could provide insight into intestinal barrier mechanisms in health and disease. Here we show that the subset of IELs that express γ and δ T cell receptor subunits (γδ IELs) promotes the viability of Paneth cells deficient in the Crohn's disease susceptibility gene ATG16L1. Using an ex vivo lymphocyte-epithelium co-culture system, we identified apoptosis inhibitor 5 (API5) as a Paneth cell-protective factor secreted by γδ IELs. In the Atg16l1-mutant mouse model, viral infection induced a loss of Paneth cells and enhanced susceptibility to intestinal injury by inhibiting the secretion of API5 from γδ IELs. Therapeutic administration of recombinant API5 protected Paneth cells in vivo in mice and ex vivo in human organoids with the ATG16L1 risk allele. Thus, we identify API5 as a protective γδ IEL effector that masks genetic susceptibility to Paneth cell death.

Inflammatory bowel diseases (IBD), including Crohn disease and ulcerative colitis, are chronic inflammatory conditions of the gastrointestinal tract. Individuals with IBD are at increased risk for several malignancies originating in the intestine, such as colorectal cancer, small bowel adenocarcinoma, intestinal lymphoma, and anal cancer. There are also several extraintestinal malignancies associated with IBD and IBD therapies, including cholangiocarcinoma, skin cancer, hematologic malignancies, genitourinary cancer, cervical cancer, and prostate cancer. The authors summarize the risk of cancer in patients with IBD, diagnosis and management of colorectal neoplasia in IBD, and management of patients with IBD and active or recent cancer.

BACKGROUND AND AIMS/OBJECTIVE: METHODS:L on the soonest peripheral blood drawn within the 48-hour window of the CDI test (before or after). Adults were eligible for the study if they were hospitalized at any one of 3 large, unaffiliated hospital networks, tested positive for CDI by stool polymerase chain reaction, and received appropriate anti-CDI treatment. Patients were followed for all-cause death for up to 30 days. RESULTS:There were 4518 unique hospitalized adults with CDI included (2142 in the derivation cohort and 2376 in the validation cohort). All-cause 30-day mortality was 9% and 10% in the cohorts. In the validation cohort, the factors most strongly associated with death were eosinopenia (adjusted odds ratio [aOR] 2.49, 95% confidence interval [CI] 1.77-3.50), albumin <3 g/dL (aOR 3.26, 95% CI 2.13-3.49), and creatinine >1.5 mg/dL (aOR 2.55, 95% CI 1.86-3.49). A 6-variable clinical prediction model was developed that improved on existing classification schemes for CDI severity (area under the receiver operating characteristic curve of 0.75 vs 0.68). CONCLUSION/CONCLUSIONS:Among adults hospitalized with CDI, peripheral eosinopenia was associated with increased risk of all-cause 30-day mortality. A prediction model incorporating peripheral eosinopenia was developed to improve care for hospitalized patients with CDI through risk stratification.

BACKGROUND & AIMS/OBJECTIVE:Postoperative Crohn's disease (CD) surveillance relies on endoscopic monitoring. The role of cross-sectional imaging is less clear. We evaluated the concordance of cross-sectional enterography with endoscopic recurrence and the predictive ability of radiography for future CD postoperative recurrence. METHODS:We performed a multi-institution retrospective cohort study of postoperative adult patients with CD who underwent ileocolonoscopy and cross-sectional enterography within 90 days of each other following ileocecal resection. Imaging studies were interpreted by blinded, expert CD radiologists. Patients were categorized by presence of endoscopic postoperative recurrence (E+) (modified Rutgeerts' score ≥i2b) or radiographic disease activity (R+) and grouped by concordance status. RESULTS:A total of 216 patients with CD with paired ileocolonoscopy and imaging were included. A majority (54.2%) exhibited concordance (34.7% E+/R+; 19.4% E-/R-) between studies. The plurality (41.7%; n = 90) were E-/R+ discordant. Imaging was highly sensitive (89.3%), with low specificity (31.8%), in detecting endoscopic postoperative recurrence. Intestinal wall thickening, luminal narrowing, mural hyper-enhancement, and length of disease on imaging were associated with endoscopic recurrence (all P < .01). Radiographic disease severity was associated with increasing Rutgeerts' score (P < .001). E-/R+ patients experienced more rapid subsequent endoscopic recurrence (hazard ratio, 4.16; P = .033) and increased rates of subsequent endoscopic (43.8% vs 22.7%) and surgical recurrence (20% vs 9.5%) than E-/R- patients (median follow-up, 4.5 years). CONCLUSIONS:Cross-sectional imaging is highly sensitive, but poorly specific, in detecting endoscopic disease activity and postoperative recurrence. Advanced radiographic disease correlates with endoscopic severity. Patients with radiographic activity in the absence of endoscopic recurrence may be at increased risk for future recurrence, and closer monitoring should be considered.

Introduction/UNASSIGNED:Diarrhea is common in persons living with HIV (PLWH)/AIDS. With the increasing utilization of multiplex gastrointestinal PCR panel (GI panel) testing, we aimed to characterize the roles of CD4 count and hospitalization in GI panel assessments of PLWH with acute diarrhea. Methods/UNASSIGNED:We performed a cross-sectional study of adult PLWH with acute diarrhea who underwent GI panel testing at two urban academic centers. Demographic, HIV disease, GI panel result, and hospitalization data were collected, and patients were cohorted by CD4 count (CD4 < 200, CD4 200-499, CD4 > = 500). The primary outcome was enteric infection as detected by GI panel, and hospitalization. Results/UNASSIGNED:, giardiasis, and multiple pathogens. MSM status independently predicted enteric infection (aOR 1.93, 95% CI: 1.02-3.67). Conclusions/UNASSIGNED:GI panel results vary by HIV disease severity and hospitalization in PLWH. Clinicians - especially in the inpatient setting - should carefully consider these factors when interpreting GI panel results. Further characterization of diarrheal etiology in PLWH with a negative GI panel is needed. Plain Language Summary/UNASSIGNED:

Gastrointestinal effects associated with Coronavirus Disease 2019 (COVID-19) are highly variable for reasons that are not understood. In this study, we used intestinal organoid-derived cultures differentiated from primary human specimens as a model to examine interindividual variability. Infection of intestinal organoids derived from different donors with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) resulted in orders of magnitude differences in virus replication in small intestinal and colonic organoid-derived monolayers. Susceptibility to infection correlated with angiotensin I converting enzyme 2 (ACE2) expression level and was independent of donor demographic or clinical features. ACE2 transcript levels in cell culture matched the amount of ACE2 in primary tissue, indicating that this feature of the intestinal epithelium is retained in the organoids. Longitudinal transcriptomics of organoid-derived monolayers identified a delayed yet robust interferon signature, the magnitude of which corresponded to the degree of SARS-CoV-2 infection. Interestingly, virus with the Omicron variant spike (S) protein infected the organoids with the highest infectivity, suggesting increased tropism of the virus for intestinal tissue. These results suggest that heterogeneity in SARS-CoV-2 replication in intestinal tissues results from differences in ACE2 levels, which may underlie variable patient outcomes.

BACKGROUND:There is little data regarding the risk of new or recurrent cancer in patients with inflammatory bowel disease (IBD) and a prior history of cancer who are exposed to ustekinumab or vedolizumab. We assessed the risk of subsequent cancer in patients exposed to these agents. METHODS:We performed a retrospective cohort study of patients with IBD and a history of cancer at an academic medical center between January 2013 and December 2020. We collected data on demographics, IBD and cancer disease characteristics, and drug exposures. The primary exposure was immunosuppressive therapy after diagnosis of cancer. The primary outcome was interval development of new or recurrent cancer. RESULTS:Of 390 patients with IBD and a previous history of cancer, 37 were exposed to vedolizumab, 14 ustekinumab, 41 antitumor necrosis factor (anti-TNF), and 31 immunomodulator; and 267 were not exposed to immunosuppression following cancer diagnosis. During a total median follow-up time of 52 months, 81 (20%) patients developed subsequent cancer: 6 (16%) were exposed to vedolizumab, 2 (14%) to ustekinumab, 3 (10%) to immunomodulators, 12 (29%) to anti-TNF, and 56 (21%) with no immunosuppression (P = .41). In a multivariable Cox model adjusting for age, IBD subtype, smoking, cancer recurrence risk, and cancer stage, there was no increase in subsequent cancer with vedolizumab (adjusted hazard ratio, 1.36; 95% CI, 0.27-7.01) or ustekinumab (adjusted hazard ratio, 0.96; 95% CI, 0.17-5.41). Patients with more than 1 biologic exposure also did not have an increased risk of subsequent cancer. CONCLUSIONS:Exposure to ustekinumab or vedolizumab in patients with IBD and a prior history of cancer does not appear to be associated with an increased risk of subsequent new or recurrent cancer.

Background: Ozanimod, a sphingosine 1-phosphate (S1P) receptor modulator selectively targeting S1P1 and S1P5, is approved in the US for the treatment of moderately to severely active ulcerative colitis (UC). In the pivotal phase 3 True North randomised controlled trial in moderate- to-severe UC, significantly more patients (pts) achieved clinical response and remission with ozanimod vs placebo (PBO) at week (wk) 10 of the induction period. Here, we report the rapidity of ozanimodinduced symptomatic response and remission in pts from True North (NCT02435992).
Method(s): In True North, pts were randomised to once-daily ozanimod 0.92 mg (equivalent to ozanimod HCl 1 mg) or PBO (Cohort 1) or received open-label ozanimod (Cohort 2) during induction. This analysis evaluated symptomatic response (defined as >=1 point and >=30% decrease from baseline in adapted partial Mayo score and >=1 point decrease from baseline in rectal bleeding score [RBS] or absolute RBS <=1) and symptomatic remission (defined as RBS of 0 and stool frequency score [SFS] <=1 point and >=1 point decrease from baseline at each study visit from wk 2 through 10.
Result(s): During induction, 645 pts were randomised to ozanimod (n=429) or PBO (n=216) in Cohort 1, and 367 pts received openlabel ozanimod in Cohort 2. Baseline demographics and clinical characteristics were well balanced across groups. Differences in symptomatic response were observed between ozanimod and PBO recipients in Cohort 1 as early as 2 wk after ozanimod initiation (1 wk post-titration) for the overall population (36.1% vs 26.4%; difference: 9.6% [95% CI, 2.1-17.0]; Figure 1) and tumour necrosis factor inhibitor (TNFi)-naive pts (38.5%, n=301 vs 29.1%, n=151; difference: 9.4% [95% CI, 0.2-18.5]), and as early as 4 wk for TNFi-exposed pts (42.2%, n=128 vs 27.7%, n=65; difference: 15.8% [95% CI, 1.8-29.8]). Differences in symptomatic remission were observed between ozanimod and PBO recipients in Cohort 1 as early as 5 wk after ozanimod initiation (4 wk post-titration) for the overall population (26.3% vs 16.7%; difference: 8.6% [95% CI, 1.8-15.4] Figure 2), as early as 4 wk for TNFi-naive pts (27.2% vs 17.9%; difference: 9.4% [95% CI, 1.5-17.4]), and as early as 8 wk for TNFi-exposed pts (22.7% vs 12.3%; difference: 11.7% [95% CI, 1.3-22.1]). Rates of symptomatic response and remission in pts receiving open-label ozanimod (Cohort 2) were similar to those in pts receiving randomised ozanimod (Cohort 1).
Conclusion(s): In the overall population, ozanimod was associated with higher rates of symptomatic response and remission vs PBO as early as 2 and 5 wk, respectively, after treatment initiation. Both clinical endpoints were more rapidly achieved in TNFi-naive vs TNFi-exposed pts