Sex differences in a murine model of asthma are time and tissue compartment dependent.

CONCLUSION: Sexual dimorphism in lung inflammation is both time and tissue compartment dependent. Spatiotemporal variability in sex differences in a murine model of asthma must be accounted for when planning experiments to model the sex bias in allergic inflammation.

Database Tracking in Gender-Affirming Surgery: Are Patients Falling Through the Cracks?

BACKGROUND: This study sought to examine risk factors for venous thromboembolism in transfeminine vaginoplasty. Secondarily, the authors outline reasons why patients are not adequately classified for research purposes despite using relevant queried codes. METHODS: Transgender patients undergoing vaginoplasty were identified with diagnostic and procedure-specific codes using a national surgical database from 2010 through 2019. RESULTS: There were 457 transgender vaginoplasties performed, with 24 wound dehiscences, 17 unplanned reoperations, and 12 surgical site infections. With zero cases of venous thromboembolism, risk factor analysis was deferred. CONCLUSIONS: Heterogeneity in coding practices for gender-affirming surgery led to an uncharacteristically small cohort of transfeminine vaginoplasty patients captured in the database. Current diagnostic and procedure-specific codes are nonspecific and unbundled, hindering accurate assessment of the incidence of standard surgical complications.

Risk Factors for Acute Postoperative Complications Following Operative Management of Le Fort Fractures-A NSQIP Study.

INTRODUCTION: Le Fort fractures comprise a pattern of complex midfacial fractures that arise secondarily to craniofacial trauma. Although management of these fractures has been detailed within the literature, there is a paucity of research examining postoperative outcomes after surgical repair. The primary aim of this study is to assess patient outcomes after operative management of Le Fort fractures, and examine factors influencing the risk for developing postoperative complications, through utilization of the ACS-NSQIP database. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for cases recorded between 2012 and 2019 with International Classification of Disease (ICD)-9 and ICD-10 codes corresponding to Le Fort fractures. Patient demographics, clinical variables, and postoperative variables were recorded. Logistic regression analysis was conducted to identify independent risk factors for postoperative complications. RESULTS: Identification of cases with appropriate ICD codes, and exclusion of those with missing data, yielded 562 patients for analysis. There were no cases of minor complications and 14 cases of severe complications (3 cases of wound dehiscence, 3 cases of transfusion requirement, 1 case of failure to wean from the ventilator for more than 48 h, 1 pulmonary embolism, and 8 cases of reoperation), corresponding to an overall complication rate of 2.49%. Logistic regression analysis revealed steroid use as an independent predictor of severe postoperative complications (OR =13.73, 95% CI: 1.08-128.02, P =0.02). CONCLUSION: The present study is the first to conduct a risk factor analysis of patients with Le Fort fractures using the ACS-NSQIP national database. The overall postoperative complication rate was 2.49%, with 14 cases of complications recorded in 8 years. Although this may suggest that surgical management of Le Fort fractures is generally well-tolerated, it should be noted that this problem is frequently associated with other severe injuries of the head and neck that may influence patient prognosis. Given this, further analysis would benefit from a larger patient cohort and longer postoperative data as the ACS-NSQIP database only records outcomes within 30 days.

More than neutrophils: Lin(+)Ly6G(+)IL-5Rα(+) multipotent myeloid cells (MMCs) are dominant in normal murine bone marrow and retain capacity to differentiate into eosinophils and monocytes.

Bone marrow is a hematopoietic site harboring multiple populations of myeloid cells in different stages of differentiation. Murine bone marrow eosinophils are traditionally identified by Siglec-F(+) staining using flow cytometry, whereas neutrophils are characterized by Ly6G(+) expression. However, using flow cytometry to characterize bone marrow hematopoietic cells in wild-type mice, we found substantial gray areas in identification of these cells. Siglec-F(+) mature eosinophil population constituted only a minority of bone marrow Lin(+)CD45(+) pool (5%). A substantial population of Siglec-F(-) cells was double positive for neutrophil marker Ly6G and eosinophil lineage marker, IL-5Rα. This granulocyte population with mixed neutrophil and eosinophil characteristics is typically attributable to neutrophil pool based on neutral granule staining and expression of Ly6G and myeloid peroxidase. It is distinct from Lineage(-) myeloid progenitors or Siglec-F(+)Ly6G(+) maturing eosinophil precursors, and can be accurately identified by Lineage(+) staining and positive expression of markers IL-5Rα and Ly6G. At 15-50% of all CD45(+) hematopoietic cells in adult mice (percentage varies by sex and age), this is a surprisingly dominant population, which increases with age in both male and female mice. RNA-seq characterization of these cells revealed a complex immune profile and the capacity to secrete constituents of the extracellular matrix. When sorted from bone marrow, these resident cells had neutrophilic phenotype but readily acquired all characteristics of eosinophils when cultured with G-CSF or IL-5, including expression of Siglec-F and granular proteins (Epx, Mbp). Surprisingly, these cells were also able to differentiate into Ly6C(+) monocytes when cultured with M-CSF. Herein described is the discovery of an unexpected hematopoietic flexibility of a dominant population of multipotent myeloid cells, typically categorized as neutrophils, but with the previously unknown plasticity to contribute to mature pools of eosinophils and monocytes.

Eosinophil accumulation in postnatal lung is specific to the primary septation phase of development.

Type 2 immune cells and eosinophils are transiently present in the lung tissue not only in pathology (allergic disease, parasite expulsion) but also during normal postnatal development. However, the lung developmental processes underlying airway recruitment of eosinophils after birth remain unexplored. We determined that in mice, mature eosinophils are transiently recruited to the lung during postnatal days 3-14, which specifically corresponds to the primary septation/alveolarization phase of lung development. Developmental eosinophils peaked during P10-14 and exhibited Siglec-Fmed/highCD11c-/low phenotypes, similar to allergic asthma models. By interrogating the lung transcriptome and proteome during peak eosinophil recruitment in postnatal development, we identified markers that functionally capture the establishment of the mesenchymal-epithelial interface (Nes, Smo, Wnt5a, Nog) and the deposition of the provisional extracellular matrix (ECM) (Tnc, Postn, Spon2, Thbs2) as a key lung morphogenetic event associating with eosinophils. Tenascin-C (TNC) was identified as one of the key ECM markers in the lung epithelial-mesenchymal interface both at the RNA and protein levels, consistently associating with eosinophils in development and disease in mice and humans. As determined by RNA-seq analysis, naïve murine eosinophils cultured with ECM enriched in TNC significantly induced expression of Siglec-F, CD11c, eosinophil peroxidase, and other markers typical for activated eosinophils in development and allergic inflammatory responses. TNC knockout mice had an altered eosinophil recruitment profile in development. Collectively, our results indicate that lung morphogenetic processes associated with heightened Type 2 immunity are not merely a tissue "background" but specifically guide immune cells both in development and pathology.