Helicobacter pylori-associated peptic ulcer disease: A retrospective analysis of post-treatment testing practices.

BACKGROUND & AIMS: Guidelines recommend that patients with Helicobacter pylori (H. pylori)-associated peptic ulcer disease (PUD) receive H. pylori eradication therapy followed by post-treatment testing to prove eradication; however, post-treatment testing rates are suboptimal and barriers to testing are poorly understood. Our aim was to identify factors that predicted receipt of post-treatment testing. METHODS: We performed a retrospective cohort study of 152 patients with H. pylori-associated PUD diagnosed between 2007 and 2015 at a large tertiary medical center in the United States, who received standard eradication therapy and ambulatory follow-up within one year. The primary outcome of interest was receipt of post-treatment testing. Logistic regression models compared post-treatment testing rates in those diagnosed while outpatient vs inpatient, patients with vs without repeat endoscopy, and patients with vs without gastroenterology (GI) clinic follow-up. Propensity scores controlled for age, sex, race, ulcer location, and symptom persistence. RESULTS: Among 152 patients, 67 (44%) patients received post-treatment testing. There were significant differences in post-treatment testing rates in those diagnosed as outpatients vs inpatients (57% vs 33%; OR 3.87, P = 0.001) and in patients with vs without GI follow-up (62% vs 11%; OR 9.85, P < 0.0001). CONCLUSIONS: The rate of testing for eradication after treatment in patients with H. pylori- associated PUD was low. However, this was significantly improved in patients who have GI follow-up and whose diagnosis was made in the outpatient setting. Our study demonstrates a clear opportunity for quality improvement initiatives.

Porcine Esophageal Submucosal Gland Culture Model Shows Capacity for Proliferation and Differentiation.

BACKGROUND & AIMS: Although cells comprising esophageal submucosal glands (ESMGs) represent a potential progenitor cell niche, new models are needed to understand their capacity to proliferate and differentiate. By histologic appearance, ESMGs have been associated with both overlying normal squamous epithelium and columnar epithelium. Our aim was to assess ESMG proliferation and differentiation in a 3-dimensional culture model. METHODS: We evaluated proliferation in human ESMGs from normal and diseased tissue by proliferating cell nuclear antigen immunohistochemistry. Next, we compared 5-ethynyl-2'-deoxyuridine labeling in porcine ESMGs in vivo before and after esophageal injury with a novel in vitro porcine organoid ESMG model. Microarray analysis of ESMGs in culture was compared with squamous epithelium and fresh ESMGs. RESULTS: Marked proliferation was observed in human ESMGs of diseased tissue. This activated ESMG state was recapitulated after esophageal injury in an in vivo porcine model, ESMGs assumed a ductal appearance with increased proliferation compared with control. Isolated and cultured porcine ESMGs produced buds with actively cycling cells and passaged to form epidermal growth factor-dependent spheroids. These spheroids were highly proliferative and were passaged multiple times. Two phenotypes of spheroids were identified: solid squamous (P63+) and hollow/ductal (cytokeratin 7+). Microarray analysis showed spheroids to be distinct from parent ESMGs and enriched for columnar transcripts. CONCLUSIONS: Our results suggest that the activated ESMG state, seen in both human disease and our porcine model, may provide a source of cells to repopulate damaged epithelium in a normal manner (squamous) or abnormally (columnar epithelium). This culture model will allow the evaluation of factors that drive ESMGs in the regeneration of injured epithelium. The raw microarray data have been uploaded to the National Center for Biotechnology Information Gene Expression Omnibus (accession number: GSE100543).

Classical Flt3L-dependent dendritic cells control immunity to protein vaccine.

DCs are critical for initiating immunity. The current paradigm in vaccine biology is that DCs migrating from peripheral tissue and classical lymphoid-resident DCs (cDCs) cooperate in the draining LNs to initiate priming and proliferation of T cells. Here, we observe subcutaneous immunity is Fms-like tyrosine kinase 3 ligand (Flt3L) dependent. Flt3L is rapidly secreted after immunization; Flt3 deletion reduces T cell responses by 50%. Flt3L enhances global T cell and humoral immunity as well as both the numbers and antigen capture capacity of migratory DCs (migDCs) and LN-resident cDCs. Surprisingly, however, we find immunity is controlled by cDCs and actively tempered in vivo by migDCs. Deletion of Langerin(+) DC or blockade of DC migration improves immunity. Consistent with an immune-regulatory role, transcriptomic analyses reveals different skin migDC subsets in both mouse and human cluster together, and share immune-suppressing gene expression and regulatory pathways. These data reveal that protective immunity to protein vaccines is controlled by Flt3L-dependent, LN-resident cDCs.

Flt3L dependence helps define an uncharacterized subset of murine cutaneous dendritic cells.

Skin-derived dendritic cells (DCs) are potent antigen-presenting cells with critical roles in both adaptive immunity and tolerance to self. Skin DCs carry antigens and constitutively migrate to the skin-draining lymph nodes (LNs). In mice, Langerin-CD11b- dermal DCs are a low-frequency, heterogeneous, migratory DC subset that traffics to LNs (Langerin-CD11b- migDCs). Here, we build on the observation that Langerin-CD11b- migDCs are Fms-like tyrosine kinase 3 ligand (Flt3L) dependent and strongly Flt3L responsive, which may relate them to classical DCs. Examination of DC capture of FITC from painted skin, DC isolation from skin explant culture, and from the skin of CCR7 knockout mice, which accumulate migDCs, demonstrate these cells are cutaneous residents. Langerin-CD11b- Flt3L-responsive DCs are largely CD24(+) and CX3CR1(low) and can be depleted from Zbtb46-DTR mice, suggesting classical DC lineage. Langerin-CD11b- migDCs present antigen with equal efficiency to other DC subsets ex vivo, including classical CD8α cDCs and Langerin+CD103+ dermal DCs. Finally, transcriptome analysis suggests a close relationship with other skin DCs, and a lineage relationship with other classical DCs. This work demonstrates that Langerin- CD11b- dermal DCs, a previously overlooked cell subset, may be an important contributor to the cutaneous immune environment.

Flt3L controls the development of radiosensitive dendritic cells in the meninges and choroid plexus of the steady-state mouse brain.

Antigen-presenting cells in the disease-free brain have been identified primarily by expression of antigens such as CD11b, CD11c, and MHC II, which can be shared by dendritic cells (DCs), microglia, and monocytes. In this study, starting with the criterion of Flt3 (FMS-like receptor tyrosine kinase 3)-dependent development, we characterize the features of authentic DCs within the meninges and choroid plexus in healthy mouse brains. Analyses of morphology, gene expression, and antigen-presenting function established a close relationship between meningeal and choroid plexus DCs (m/chDCs) and spleen DCs. DCs in both sites shared an intrinsic requirement for Flt3 ligand. Microarrays revealed differences in expression of transcripts encoding surface molecules, transcription factors, pattern recognition receptors, and other genes in m/chDCs compared with monocytes and microglia. Migrating pre-DC progenitors from bone marrow gave rise to m/chDCs that had a 5-7-d half-life. In contrast to microglia, DCs actively present self-antigens and stimulate T cells. Therefore, the meninges and choroid plexus of a steady-state brain contain DCs that derive from local precursors and exhibit a differentiation and antigen-presenting program similar to spleen DCs and distinct from microglia.