Citations

Abstract In human melanoma, tumor cell-specific MHC class II expression is associated with improved response to programmed death 1 and programmed death-ligand 1 blockade; yet the direct effect of melanoma cell-specific MHC class II expression on anti-melanoma T cell responses remains largely unknown. In the clinically relevant Yale University Mouse Melanoma Exposed to Radiation (YUMMER) cell lines, MHC class II expression was IFN-γ-inducible in a subset of cells. Transduction of melanoma cells with CIITA resulted in uniformly high, constitutive expression of MHC class II. YUMMER.G cells transduced with CIITA vector had increased in vivo tumor growth in wild-type mice compared to melanoma cells transduced with empty vector. YUMMER.G cells transduced with empty or CIITA vectors had the same in vivo tumor growth in RAG−/− mice, indicating that the difference in tumor growth between CIITA- and empty-transduced cells was dependent on an intact adaptive immune system. CIITA-transduced YUMMER.G tumors exhibited an increased frequency and infiltration depth of CD4+ T cells, an increased frequency of T regulatory cells, and a decreased frequency and infiltration depth of CD8+ T cells, compared to empty-transduced tumors. Antibody depletion revealed that CIITA- and empty-transduced YUMMER.G tumors were constrained by CD4+ and CD8+ T cells, but only tumor growth of CIITA-transduced cells was decreased by CD25 blockade, which primarily blocks T regulatory cell function. Overall, this work reveals a potential pro-tumorigenic role of melanoma cell-specific overexpression of MHC class II.

Abstract Background Acute hypoxemic and hypercapnic respiratory failure are among the most common reasons for ICU admission and need for invasive mechanical ventilation. Noninvasive respiratory support (NIRS) strategies—including high-flow nasal cannula (HFNC), noninvasive ventilation (NIV), and continuous positive airway pressure (CPAP)—may prevent intubation, improve outcomes, and reduce ICU utilization. However, there is uncertainty regarding optimal patient and modality selection, resulting in variable implementation. There are no clinical practice guidelines comprehensively addressing the use of the different noninvasive respiratory support strategies across the spectrum of acute respiratory failure. Objective To update and develop new evidence-based clinical practice recommendations informing noninvasive respiratory support use, including HFNC, NIV and CPAP, in adults with acute respiratory failure. Methods A multidisciplinary panel used the GRADE approach to address four PICO questions related to the use of NIRS for hypoxemic and hypercapnic respiratory failure, preoxygenation for intubation, and post-extubation respiratory support. Recommendations were informed by several systematic reviews and network meta-analyses. Results The panel made a strong recommendation for HFNC and a conditional recommendation for NIV or CPAP for adults with acute hypoxemic respiratory failure with close monitoring for the need for escalation of respiratory support, based primarily on effects on need for intubation. For acute hypercapnic respiratory failure, the panel made a strong recommendation for NIV to reduce mortality and need for invasive mechanical ventilation, and a conditional recommendation for HFNC only in patients with less severe hypercapnia and with mild acidemia (eg, pH > 7.25), provided that close monitoring and prompt escalation to NIV are available. The panel made a strong recommendation for HFNC or NIV for preoxygenation prior to endotracheal intubation to prevent peri-intubation hypoxemia. The panel also issued a risk-based recommendation, suggesting HFNC for low-risk patients and NIV for high-risk patients to reduce the need for re-intubation following extubation after critical illness. Conclusions Noninvasive respiratory support strategies are effective in improving outcomes in a range of clinical scenarios. We provide evidence-based recommendations, which can be further informed by patient risk, institutional capacity, and interface tolerance.

Abstract Macrophages in the tumor microenvironment are known to upregulate PD-L1 expression, thereby suppressing T cells through PD-1 ligation. However, the manner in which PD-L1 expression intrinsically impacts macrophages and their immunomodulatory phenotype is less clear. Clarifying this knowledge gap would yield insight into the mechanisms of immunosuppression within the tumor microenvironment. To characterize the macrophage intrinsic role of PD-L1, we used complementary genetic and pharmacological approaches by analyzing primary murine bone marrow-derived macrophages (BMDMs) with complete genetic PD-L1 deletion and wildtype BMDMs treated with anti-PD-L1 blocking antibodies. Macrophages were evaluated across naïve, pro-inflammatory (M1), and tumor conditioned (TCM) polarization states in vitro. Unlike prior reports, neither genetic deletion nor antibody blockade dramatically altered the expression of macrophage polarization markers or in vitro phagocytic capacity. Both conditions consistently reduced surface levels of the M1-associated costimulatory molecule CD80, prompting further analysis of T cell interacting and antigen presenting proteins, in which we revealed disparate effects of genetic deletion and antibody blockade on the surface levels of MHCI, MHCII, PD-1, and PD-L2. These findings suggest that PD-L1 deletion and antibody-mediated blockade contribute to macrophage immune regulatory profiles in distinct manners. This difference supports a model in which PD-L1 functions in macrophages beyond its canonical role as a ligand for PD-1, influencing antigen presentation and checkpoint molecule levels and playing a broader role in immune regulation in the tumor microenvironment.

This Viewpoint describes a plateau in the discovery of clinically meaningful autoantibodies in autoimmune encephalitis (AE) and suggests efforts that are likely to offer greater benefits to patients living with AE.

This Viewpoint discusses the discovery of numerous neuronal autoantibodies and how autoimmune encephalitis is diagnosed and treated.

Abstract Objective To describe the presenting symptoms, treatment regimens, and outcomes associated with oropharyngeal adenoid cystic carcinoma. Data Sources Ovid MEDLINE(R), Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, and Scopus via Elsevier. Review Methods This review followed the Preferred Reporting Items for Systematic Reviews and Meta‐analyses. A medical librarian conducted the literature search using controlled vocabulary and keywords, with investigator input. Eligible articles were clinical trials and observational studies reporting on clinical features, treatment, or outcomes for oropharyngeal adenoid cystic carcinoma. Results Our search identified 233 unique citations, with 44 articles included covering 195 patients. The female‐to‐male ratio was 1.7:1, and the base of the tongue was the most common subsite (73%). Presenting symptoms were mainly pain/discomfort (n = 31), followed by a palpable mass (n = 19) and dysphagia (n = 12). At diagnosis, 22.3% (29 patients) had positive lymph nodes. Treatment was primarily surgical (n = 102), with definitive radiation therapy used in 58 cases. Disease progression was noted in 86 patients, 36% (n = 31) of whom developed distant metastases—primarily to the lungs (n = 26). Long‐term outcomes (n = 76) showed 3‐ and 5‐year overall survival rates of 71.5% to 100% and 47.6% to 79.0%, and disease‐free survival rates of 54.7% to 70.0% and 21.9% to 44.0%, respectively. Conclusion Among patients with available data, oropharyngeal adenoid cystic carcinoma appeared more common in women and has a predilection for the base of the tongue. However, this finding should be interpreted with caution, given the high proportion of missing data. These tumors appear to carry a higher risk for nodal metastases and may lead to poor outcomes.

This review aims to evaluate the treatment and outcomes of femur fractures in children with cerebral palsy (CP). Femur fractures are common in this population because of physiological and mechanical factors. Treatment approaches vary based on functional status and fracture characteristics. Medline, Embase, Central, and Scopus databases were systematically searched for studies investigating outcomes following femur fractures in children aged 0–18 with CP who received surgical or nonsurgical treatment. Primary outcomes were fracture location, ambulatory status, treatment types, and complications. A meta-analysis was conducted when data homogeneity permitted, using mean differences for continuous outcomes and risk ratios for dichotomous outcomes. Of 213 screened articles, seven were included, reporting 335 femur fractures in 258 patients. Most fractures occurred in the distal femur (52%) followed by mid-diaphyseal fractures (32%). Treatment varied by ambulatory status and fracture location, with 60% managed nonoperatively, typically in nonambulatory patients and for distal fractures. Nonoperative treatment, mainly spica casting, showed higher malunion rates (29%) and complications like pressure sores (11%). In contrast, operative treatment, preferred for proximal and mid-diaphyseal fractures, resulted in lower malunion rates in nonambulatory children (7%; P = 0.02) but had risks of postoperative pneumonia (6%) and surgical site infection (13%). Outcomes indicated improved healing and function with operative treatments in ambulatory children. Femur fractures in children with CP require individualized treatments based on the patient’s fracture type and ambulatory status. Future studies should incorporate fracture mitigation metrics, functional outcomes, and caregiver impact to inform optimal patient-centered care.