Citations

Background: The majority of randomized controlled trials of revascularization decision-making excludes left main coronary artery disease (LMD). Therefore, contemporary clinical outcomes of patients with stable coronary artery disease and LMD with proven ischemia remain poorly understood. The aim of this study was to assess the long-term clinical outcomes of physiologically significant LMD according to the treatment strategies of revascularization versus revascularization deferral. Methods: In this international multicenter registry of stable LMD interrogated with the instantaneous wave-free ratio, patients with physiologically significant ischemia (instantaneous wave-free ratio ≤0.89) were analyzed according to the coronary revascularization (n=151) versus revascularization deferral (n=74). Propensity score matching was performed to adjust for baseline clinical characteristics. The primary end point was a composite of death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization of left main stem. The secondary end points were as follows: cardiac death or spontaneous LMD-related myocardial infarction; and ischemia-driven target lesion revascularization of left main stem. Results: At a median follow-up period of 2.8 years, the primary end point occurred in 11 patients (14.9%) in the revascularized group and 21 patients (28.4%) in the deferred group (hazard ratio, 0.42 [95% CI, 0.20–0.89]; P =0.023). For the secondary end points, cardiac death or LMD-related myocardial infarction occurred significantly less frequently in the revascularized group (0.0% versus 8.1%; P =0.004). The rate of ischemia-driven target lesion revascularization of left main stem was also significantly lower in the revascularized group (5.4% versus 17.6%; hazard ratio, 0.20 [95% CI, 0.056–0.70]; P =0.012). Conclusions: In patients who underwent revascularization for stable coronary artery disease and physiologically significant LMD determined by instantaneous wave-free ratio, the long-term clinical outcomes were significantly improved as compared with those in whom revascularization was deferred.

Abstract Food allergy, such as peanut allergy can cause life-threatening anaphylaxis. While T follicular helper (Tfh) cells play a major role in production of allergen-specific IgE and IgG antibodies, the immunologic mechanisms that regulate the production of antibodies that mediate anaphylaxis are not well understood. While PD-1 is highly expressed on Tfh cells, our knowledge is limited regarding the role of the molecule in Tfh cells. Thus, the objective of this study was to investigate the roles of PD-1 in allergic immune responses using a mouse model of peanut allergy. Naïve wild-type mice were exposed to peanut flour intranasally (i.n.) and then challenged by intraperitoneal (i.p.) injection of peanut extract. The mice exposed i.n. to peanut flour produced peanut-specific IgE and IgG antibodies and developed anaphylaxis when challenged i.p. with peanut extract. PD-1 blockade with anti-PD-1 treatment Tfh and germinal center B cell numbers in mice exposed to peanut flour. Nonetheless, anti-PD-1 or anti-PD-L1 fully protected mice from anaphylaxis. Anti-PD-1 or genetic deficiency of PD-1 in CD4+ T cells reduced and increased levels of peanut-specific IgE and IgG, respectively. Anti-PD-1 promoted production of low-affinity IgE and IgG antibodies with no effect on high-affinity antibodies. By passive cutaneous anaphylaxis, peanut-specific antibodies generated in anti-PD1 treated mice failed to induce anaphylaxis, and plasma from these mice prevented anaphylaxis. Therefore, blockade of the PD-1 pathway is protective against allergic immune responses. The interaction between Tfh cells and B cells may play a pivotal role in controlling antibody quality and clinical manifestation of allergic diseases.

Abstract We investigated whether human IgM antibody, B7-DCXAb, which binds to B7-DC and enhances DCs' antigen uptake and retention, migration, and cytokine production, improves the efficacy of allergen immunotherapy. Mice were sensitized by intraperitoneal injection of OVA or house dust mite (HDM) antigens plus alum and then treated by intravenous B7-DCXAb injection intranasal or sublingual administration of antigen. OVA-sensitized mice developed anti-OVA IgE and IgG1, Th2-type splenocyte responses to OVA; marked airway eosinophilic inflammation was observed after intranasal OVA challenge. When these mice were treated by intravenous B7-DCXAb plus intranasal OVA, anti-OVA IgE and IgG1 decreased by 75~95% within 1 week; this decrease persisted for >8 weeks. Anti-OVA IgG2a decreased transiently. Splenocyte production of IL-4, IL-5, and IL-13 in response to OVA was abolished; no increases in IFN-g or IL-17 were noted. In OVA-challenged mice, airway eosinophilia and lung levels of IL-4, IL-5 and IL-13 were reduced by >90%. Immunotherapeutic effects were also observed with intravenous B7-DCXAb plus sublingual OVA, but not with intravenous B7-DCXAb alone. Furthermore, HDM-sensitized mice were treated successfully by intravenous B7-DCXAb plus intranasal HDM. B7-DCXAb injection plus mucosal administration of antigen effectively treats allergic responses and may provide novel strategy for allergen immunotherapy.

Abstract Peanut allergies are life-long diseases that cause severe anaphylactic responses to affected individuals. Oral ingestion of peanut products prevents infants from developing peanut allergy. However, little information is currently available regarding the immunologic mechanisms for this protection. Therefore, the goal of this project was to establish an oral tolerance model to peanut allergy in mice and to determine the immunologic mechanisms. Naïve BALB/c mice that were exposed intranasally (i.n.) to peanut flour (PNf) developed peanut allergy as demonstrated by increased serum levels of IgE antibody as well as acute anaphylactic response when challenged with peanut extract. When mice were fed peanut butter (PNB) prior to i.n PNf exposure, they were protected from developing peanut allergy; these mice showed decreased serum levels of IgE antibody and lacked anaphylactic response. T follicular helper (Tfh) cells and germinal center (GC) B cells were decreased in lung draining lymph nodes of mice fed PNB. Furthermore, scRNSseq revealed 2 distinct CD4+ T cell subpopulations that are increased in those protected mice. CTLA-4, a checkpoint molecule, was highly expressed in one of these subpopulations. Systemic administration of a CTLA-4 blocking antibody to mice fed PNB increased the numbers of Tfh cells and GC B cells and increased serum levels of IgE antibody. Finally, anti-CTLA-4 reversed the clinical efficacy of oral PNB administration, resulting in manifestation of acute anaphylaxis when challenged with peanut extract. Thus, oral administration of peanut product(s) prevents development of peanut allergy in mice. CTLA4+CD4+ T cells likely play a pivotal role in this process by regulating the development of Tfh cells.

Abstract CD8+ T cells represent a relatively under studied cell type in allergic lung inflammation, despite their presence in the mucosal tissues. This is because CD8+ T cells are normally associated with a Th1 response as opposed to Th2 or Th17 responses, as are the most cases with allergic inflammation. However, recent papers have shown the production of Th2 and Th17 cytokines in these cells, yet knowledge of their physiological role in allergic inflammation is incomplete. The presence of IL-17 in asthma patients contributes to a severe, steroid resistant phenotype. Therefore, determining contributors of IL-17 and their physiological role is paramount to understanding the disease. Our preliminary data which suggests memory Tc17 cells are generated in CD4-/- mice when sensitized intranasally to ovalbumin with IL-33. We believe Tc17 cells are responsible for the inflammation because the inflamed lung tissue contained elevated IL-17, and stimulated T cells from inflamed tissue produced elevated levels of IL-17 as well. Additionally, we were unable to induce inflammation in Rag-/- mice or TCRβ-/- mice, which pinpoints the cell responsible to CD8+ T cells in CD4-/- mice. Using these mice to study an exaggerated phenotype will allow us to more easily detect the contributions that happen to a lesser degree in wild type animals. This work create a more complete picture of the disease environment and lead to therapies which can account for the contribution of this cell type.

Abstract We used an established model of asthma that involves intranasal administration of the fungal extract of Alternaria. Upon lung exposure to Alternaria, IL-33 was released by epithelial cells within one hour, followed by increased production of IL-5 in the lungs. We also found elevated serum levels of IL-5 in response to Alternaria exposure, which reached a peak at 6 hours post Alternaria administration. After prolonged exposure to Alternaria over 6 days, a significant increase in mature eosinophils was observed in bone marrow. In addition, the serum from mice challenged with Alternaria was able to stimulate bone marrow cells to undergo eosinophil maturation in vitro. Intraperitoneal administration of IL-5-blocking antibody in vivo decreased eosinophil maturation in bone marrow in response to intranasal Alternaria below intranasal PBS baseline levels. We have shown the source of IL-5 is by type 2 innate lymphoid cells directly through IL-5 reporter mice, and indirectly through IL-5 serum levels in CD127 knockout mice. Taken together, this study illustrates that the type 2 innate immune responses in the lungs leads to enhanced production of eosinophils in the bone marrow through the increase in lung and blood levels of IL-5. Thus, distant organs communicate during allergic inflammation by using cytokines as mediators. This concept will aid in the identification of novel therapeutic strategies to alleviate symptoms of asthma and allergic diseases.

Abstract Interleukin (IL)-1 family member cytokines are likely pivotal as interfaces between innate and adaptive immune responses. IL-33, an IL-1 family member, is implicated in airway Th2-type responses, including eosinophilia, increased mucus production and hyperresponsiveness. Our goal was to elucidate the immunological mechanisms involved in IL-33-mediated Th2-type responses in the lungs. Airway exposure of naïve BALB/c mice to IL-33 resulted in bronchoalveolar lavage (BAL) eosinophilia and increased lung levels of IL-5 and IL-13, but not IL-4 or IFNγ. Naïve Rag1-/- mice showed similar airway eosinophilia and cytokine responses as wild-type mice, suggesting a role for innate immune cells. By FACS analysis, IL-5-producing lung cells lacked CD3, B220 and other lineage markers (i.e. Lin-), but they expressed CD44 and CD25; markers for NK cells, mast cells, basophils and eosinophils were undetectable. FACS-sorted Lin-CD25+CD44+ lung cells expressed GATA-3 and the IL-33 receptor, T1/ST2, and responded to IL-33 by producing IL-5 and IL-13; morphologically, these lung cells resembled lymphocytes. In vitro blockade of CD25+ cells with anti-CD25 mAb (PC61) abrogated IL-33-induced Th2 cytokine production. Thus, mouse lungs contain a novel subset of innate immune cells that respond to IL-33. These airway cells may initiate early Th2-type immune responses and induce asthma and other allergic diseases.

Abstract We tested the effects of different cytokines on IgA- and IgG-induced eosinophil degranulation in vitro to determine the potential interaction between eosinophils and mononuclear cells. Purified normodense eosinophils were incubated with cytokines (including rIL-1, rIL-2, rIL-3, rIL-4, rIL-5, rIL-6, IFN-gamma, granulocyte-macrophage CSF stimulating factor (GM-CSF), and TNF) for 1 to 3 h after which Ig-coupled Sepharose 4B beads were added as targets and the mixtures were incubated with the eosinophils at 37 degrees C for 4 h. The Ig used were secretory IgA (sIgA), serum IgA and IgG, and myeloma IgA and IgG. The release of eosinophil-derived neurotoxin (EDN) was measured by RIA as an index of degranulation. rIL-5 was the most potent enhancer of Ig-induced degranulation and increased EDN release by 48% for sIgA and 136% for IgG. The effect of rIL-5 appeared as quickly as 15 min after incubation of eosinophils, sIgA beads and IL-5. GM-CSF and rIL-3 also enhanced Ig-induced EDN release but less potently than rIL-5. GM-CSF and rIL-5 by themselves induced a small but significant release of EDN from eosinophils in the absence of Ig-coated beads; rIL-3 did not. However, IFN-gamma suppressed sIgA-induced EDN release by 23%. The other cytokines did not have any effect on eosinophil degranulation. These results suggest that cytokines which induce eosinophil differentiation and proliferation during hematopoiesis also enhance the effector function of mature eosinophils and that IFN-gamma partially down-regulates eosinophil degranulation.

Abstract Eosinophils play an important role as effector cells in allergic, parasitic, and other conditions. The mechanism(s) by which eosinophils mediate their effector functions was studied by incubation of human normodense eosinophils with Sepharose beads coupled to various Ig isotypes as targets. Controls included eosinophils incubated alone or incubated with uncoated beads, human serum albumin-, or OVA-coated beads. An eosinophil granule protein, the eosinophil-derived neurotoxin (EDN), was measured as an indicator of eosinophil degranulation. Eosinophils released eosinophil-derived neurotoxin when incubated with Sepharose beads coupled to Ig of the IgG or IgA isotypes, as well as IgA-Fc fragments. Mixtures of IgG and IgA on beads did not act synergistically. Secretory IgA (sIgA) provided the most potent signal for eosinophil degranulation and was two to three times more potent than IgG. Furthermore, 2 to 17% of the normodense eosinophils bound to IgG- or IgA-coated beads, whereas 24 to 27% of the eosinophils bound to sIgA-coated beads. Thus, sIgA may be the principal Ig mediating eosinophil effector function at mucosal surfaces in helminth infections and hypersensitivity diseases, especially bronchial asthma.

AbstractBackgroundThe anatomical structure around the pancreatic head is very complex and it is important to understand its precise anatomy and corresponding anatomical approach to safely perform minimally invasive pancreatoduodenectomy (MIPD). This consensus statement aimed to develop recommendations for elucidating the anatomy and surgical approaches to MIPD.MethodsStudies identified via a comprehensive literature search were classified using the Scottish Intercollegiate Guidelines Network method. Delphi voting was conducted after experts had drafted recommendations, with a goal of obtaining >75% consensus. Experts discussed the revised recommendations with the validation committee and an international audience of 384 attendees. Finalized recommendations were made after a second round of online Delphi voting.ResultsThree clinical questions were addressed, providing six recommendations. All recommendations reached at least a consensus of 75%. Preoperatively evaluating the presence of anatomical variations and superior mesenteric artery (SMA) and superior mesenteric vein (SMV) branching patterns was recommended. Moreover, it was recommended to fully understand the anatomical approach to SMA and intraoperatively confirm the SMA course based on each anatomical landmark before initiating dissection.ConclusionsMIPD experts suggest that surgical trainees perform resection based on precise anatomical landmarks for safe and reliable MIPD.