Intensivist -Driven Ventilator Management Shortens Duration of Mechanical Ventilation in Coronary Artery Bypass Graft Surgery Patients.

BACKGROUND: Prolonged mechanical ventilation in post Coronary Artery Bypass Graft Surgery (CABG) is associated with deleterious effects including, increased ICU and hospital length of stay (LOS), infectious complications, and mortality. Standardized ventilator weaning protocols and the utilization of critical care physicians in post CABG patient care vary substantially among institutions. The purpose of this study was to evaluate if intensivist consultation in conjunction with a multidisciplinary, standardized ventilator weaning protocol improves outcomes in CABG patients. MATERIALS AND METHODS: We performed a single-center, retrospective, before-after cohort analysis at Miami Valley Hospital in Dayton, OH, a 970-bed community hospital. Patients were divided into two arms: the before cohort or delayed-consult group (critical care consult after six hours on ventilator) and after cohort or immediate-consult group (immediate critical care consult). All patients were weaned from ventilator using a standardized weaning protocol. RESULTS: A total of 764 patients were enrolled, 411 in the delayed-consult group and 353 in the immediate-consult group. The immediate-consult group had less time on initial mechanical ventilation than the delayed-consult group (5.86 ± 4.75 h vs. 6.00 ± 6.64 h, P = 0.038). The small advantages to immediate critical care consultation for higher percent of early extubations, fewer re-intubations, shorter ICU LOS, and lower rate of ICU readmission were not statistically significant. The two groups had similar ventilator free days, prolonged mechanical ventilation, hospital LOS, and in-hospital mortality. CONCLUSION: Our study suggests that intensivist-driven ventilator management in conjunction with a multidisciplinary standardized weaning protocol shortens duration of mechanical ventilation in coronary artery bypass graft surgery patients.

TRAF2 Deficiency in B Cells Impairs CD40-Induced Isotype Switching That Can Be Rescued by Restoring NF-κB1 Activation.

Effective humoral immunity requires class switch recombination (CSR) catalyzed by activation-induced cytidine deaminase (AID). In response to T cell-dependent (TD) Ags, CSR can be induced by CD40 signaling in B cells. TNFR-associated factors 2 and 3 (TRAF2/TRAF3) function as adaptors of the CD40 signaling pathway. B cell-intrinsic TRAF2 or TRAF3 (B-TRAF2 or B-TRAF3) knockout mice were previously reported to have indistinguishable phenotypes in gene expression, B cell survival and development, and enlarged peripheral lymphoid organs. However, it remains unknown whether deficiency of B-TRAF2 or B-TRAF3 differentially affects TD humoral immune responses and CD40-induced CSR. In this article, we show that B-TRAF2 is essential for optimal isotype switching induced by in vivo TD Ag immunization or by engaging CD40 in vitro. Our data clarify the controversial role of B-TRAF3 and confirm its dispensability in CD40-induced CSR. Mechanistically, CD40-induced AID expression was markedly impaired by B-TRAF2, but not B-TRAF3, deficiency. Moreover, B-TRAF2 deficiency causes defective activation of the NF-κB1 complex in a CD40-autonomous manner, and restoring CD40-induced NF-κB1 activation in TRAF2-deficient B cells rescues AID expression and CSR. We conclude that TRAF2 is essential but TRAF3 is dispensable for TD humoral immunity and CD40-induced CSR. Our studies provide significant biological bases for optimizing treatment of B cell-associated immune disorders by targeting CD40 signaling.

Imbalanced PTEN and PI3K Signaling Impairs Class Switch Recombination.

Class switch recombination (CSR) generates isotype-switched Abs with distinct effector functions. B cells express phosphatase and tensin homolog (PTEN) and multiple isoforms of class IA PI3K catalytic subunits, including p110α and p110δ, whose roles in CSR remain unknown or controversial. In this article, we demonstrate a direct effect of PTEN on CSR signaling by acute deletion of Pten specifically in mature B cells, thereby excluding the developmental impact of Pten deletion. We show that mature B cell-specific PTEN overexpression enhances CSR. More importantly, we establish a critical role for p110α in CSR. Furthermore, we identify a cooperative role for p110α and p110δ in suppressing CSR. Mechanistically, dysregulation of p110α or PTEN inversely affects activation-induced deaminase expression via modulating AKT activity. Thus, our study reveals that a signaling balance between PTEN and PI3K isoforms is essential to maintain normal CSR.

Pembrolizumab and tavokinogene telseplasmid electroporation in metastatic melanoma.

INTRODUCTION: Tavokinogene Telseplasmid Electroporation Therapy (TAVO) and Pembrolizumab therapy is being studied in subjects with immune checkpoint inhibitor (ICI) resistant melanoma. TAVO is a novel office-based local therapy shown to be effective in patients with advanced melanoma. The technique involves the direct injection of a plasmid encoding IL-12 into an accessible tumor driven by electroporation. The tumor cells have then been shown to express high levels of IL-12 resulting in a local inflammatory response within the tumor microenvironment. PRESENTATION OF CASE: The patient with stage IIB, pT3b melanoma was treated with primary tumor resection and found to have a negative sentinel node biopsy. She subsequently developed regional recurrence and was treated with inguinal lymphadenectomy and adjuvant Nivolumab. Despite therapy, she had progression of disease with skin and subcutaneous metastases (in-transit lesions), brain and liver lesions, hilar and iliac nodal disease. She was transitioned to nivolumab + ipilimumab, and Talimogene Laherparepvec (T-VEC) therapy for the in-transit lesions, without success. Stereotactic radiosurgery was used for the brain metastasis. Groin subcutaneous and in-transit lesions were treated with TAVO and intravenous pembrolizumab. Serial physical exams and CT scans were used to assess response. DISCUSSION: All lesions treated with TAVO resolved. An abscopal response was also noted: hilar and mediastinal lymphadenopathy resolved. The liver mass and pelvic lymphadenopathy decreased in size, and her brain metastasis remained stable after radiation. CONCLUSION: This case suggests that combination TAVO and Pembrolizumab is a safe and effective local treatment for ICI resistant metastatic melanoma in the setting of rheumatoid arthritis. An abscopal effect was also noted through control of systemic disease.