Newborns are unable to mount antibody responses towards certain antigens. This has been related to the restricted repertoire of immunoglobulin (Ig) genes of their B cells. The mechanisms underlying the restricted fetal Ig gene repertoire are currently unresolved. We here addressed this with detailed molecular and cellular analysis of human precursor-B cells from fetal liver, fetal bone marrow (BM), and pediatric BM. In the absence of selection processes, fetal B-cell progenitors more frequently used proximal V, D and J genes in complete IGH gene rearrangements, despite normal Ig locus contraction. Fewer N-nucleotides were added in IGH gene rearrangements in the context of low TdT and XRCC4 expression. Moreover, fetal progenitor-B cells expressed lower levels of IL7Rα than their pediatric counterparts. Analysis of progenitor-B cells from IL7Rα-deficient patients revealed that TdT expression and N-nucleotides additions in Dh-Jh junctions were dependent on functional IL7Rα. Thus, IL7Rα affects TdT expression, and decreased expression of this receptor underlies at least in part the skewed Ig repertoire formation in fetal B-cell precursors. These new insights provide a better understanding of the formation of adaptive immunity in the developing fetus.

Iterative reconstruction algorithms affected lesion detection differently at different dose levels. One iterative algorithm improved lesion detectability compared to filtered back projection. Three algorithms did not significantly improve lesion detectability. One algorithm improved lesion detectability at the lowest dose level.

BackgroundGoblet cell carcinoid is a rare but distinct entity of appendiceal tumors which is a hybrid or mixed tumor consisting of both epithelial (glandular) and neuroendocrine elements containing goblet cells. This entity is important to recognize and appropriately grade as it tends to be more aggressive than typical carcinoid tumors, often presenting with metastatic disease. As a result, the 5-year overall survival is 14–22% in stage III–IV disease. GCC therefore warrants more aggressive surgical and medical (chemotherapy) interventions than typical carcinoid tumors. Through this case report we give a brief update on GCC pathological features, staging, surgical management, and review the literature as a guide to indications for chemotherapy and choice of agents.Case presentationWe present the case of a 77-year-old Caucasian man with a history of stage I adenocarcinoma of transverse colon status post transverse colectomy who was incidentally found on surveillance colonoscopy to have an abnormal appendiceal orifice lesion. A biopsy revealed an appendiceal goblet cell carcinoid and he underwent a right hemicolectomy which revealed a pathologic stage III GCC for which he received eight cycles of adjuvant chemotherapy with capecitabine.ConclusionsIt is essential that patients who have tumors > 2 cm, are pT3 or pT4, have higher grade histology with signet ring (Tang grade B or grade C), locally advanced, or with positive surgical margins on appendectomy undergo a right hemicolectomy. Although there is no category 1 evidence, consensus recommendations are that patients with stage II (particularly Tang B and C) and stage III GCC be offered adjuvant chemotherapy with a regimen based on 5-fluorouracil, as these patients are known to have high rates of relapse.