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Our laboratory has been investigating the role of B cells on tumor immunity. We have studied the immune response in mice that are genetically lacking in B cells (BCDM) using a variety of syngeneic mouse tumors and compared immune responses in BCDM with those seen in wild type (WT) immunocompetent mice (ICM). A variety of murine tumors are rejected or inhibited in their growth in BCDM, compared with ICM, including the EL4 thymoma, and the MC38 colon carcinoma in C57BL/6 mice, as well as the EMT-6 breast carcinoma in BALB/c mice. In all three murine models, tumors show reduced growth in BCDM which is accompanied by increased T cell and NK cell infiltration, and a more vigorous Th1 cytokine response, and increased cytolytic T cell response in the absence of B cells. Reconstitution of the mice with B cells results in augmented tumor growth due to a diminished anti-tumor immune response and in reduction in CD8+ T cell and NK cell infiltration. Studies involving BCR transgenic mice indicated that B cells inhibit anti-tumor T cell responses through antigen non-specific mechanisms. More recent studies using the EMT-6 model demonstrated that both the number and function of Treg cells in ICM was increased relative to that seen in BCDM. Increased expansion of Treg cells was evident following EMT-6 implantation in ICM relative to that seen in non-tumor-bearing mice or BCDM. The percentage and number of Tregs in spleen, tumor draining lymph nodes, and the tumor bed are increased in ICM compared with BCDM. Treg functional capacity as measured by suppression assays appears to be reduced in BCDM compared with ICM. In contrast to other described types of B regulatory activity, adoptive transfer of B cells can rescue tumor growth independently of the ability of B cells to secrete IL-10, and also independently of MHC-II expression. In experiments using the MC38 adenocarcinoma model, BCDM reconstituted with WT B cells support tumor growth while tumor growth continues to be inhibited in BCDM reconstituted with OX40L(-/-) B cells. This suggests that interaction between OX40 on T cells and OX40-ligand on B cells may be important in modulating anti-tumor immune response. Ongoing experiments in the laboratory indicate that B cells migrate to the site of tumor and acquire expression of immunosuppressive ligands and/or cytokines that contribute to the inhibition of anti-tumor immune response. Significant infiltration of human tumors by Treg cells as well as B cells suggests that observations made in murine systems may be applicable to human tumors as well.

Case series Patients: Male, 72-year-old • Male, 65-year-old • Male, 48-year-old Final Diagnosis: COVID-19 pneumonia Symptoms: Cough • dynpnea • fever Medication: — Clinical Procedure: Endotracheal intubation Specialty: Critical Care Medicine • Infectious Diseases • General and Internal Medicine • Microbiology and Virology • Pulmonology Objective: Unusual clinical course Background: COVID-19, the disease entity caused by the novel severe acute respiratory coronavirus 2 (SARS-CoV-2), continues to pose a major therapeutic challenge for clinicians. At present, an effective treatment regimen and vacci-nation has not been established. Many patients develop severe symptoms requiring endotracheal intubation and a prolonged stay in the Intensive Care Unit (ICU). In early postmortem examinations of COVID-19 patients, profuse viscous secretions were observed throughout the respiratory tract. Thus, oxygen supplementation without aggressive pulmonary hygiene management may be suboptimal. In the present case series, pulmonary hygiene management encompassed mucolytics, bronchodilators, and tracheal suctioning. We report 3 severe cases of COVID-19 pneumonia in cruise ship employees who were admitted to the ICU and responded to supportive mechanical ventilation and pulmonary hygiene management. Case Reports: Three cruise ship employees with COVID-19 underwent endotracheal intubation and were admitted to the ICU for acute hypoxemic respiratory failure. Initial chest X-rays suggested multifocal pneumonia with superimposed acute respiratory distress syndrome (ARDS). A regimen of hydroxychloroquine, azithromycin, and dexamethasone was initiated on admission in all cases. Additionally, medications used for pulmonary hygiene were administered through a metered-dose inhaler (MDI) in line with the ventilator circuit. Endotracheal suctioning was performed prior to medication administration. The duration from endotracheal intubation to extubation ranged from 9 to 24 days. All 3 patients reached 30-day survival. Conclusions: The cases reported highlight the importance of the use of airway hygiene with mucolytics, bronchodilators, and tracheal suctioning for patients with COVID-19 pneumonia requiring ventilatory support.

COVID-19, caused by the novel severe acute respiratory coronavirus 2 (SARS-CoV-2), emerged in Wuhan, China, in 2019 and has resulted in the current pandemic. The disease continues to pose a major therapeutic challenge. Patient mortality is ultimately caused by acute respiratory distress syndrome (ARDS). Cytokine release syndrome (or “cytokine storm”) is likely to be a contributing factor to ARDS in many patients. Because interleukin 6 (IL-6) is known to play a key role in inflammation, IL-6 receptor inhibitors such as tocilizumab may potentially treat COVID-19 by attenuating cytokine release. We present the case of a 48-year-old male with severe COVID-19, on the verge of meeting intubation requirements, who needed progressive oxygen support for respiratory distress. The patient was treated with a non-weight-based dosage of tocilizumab to prevent the onset of a cytokine storm. We chose to administer an IL-6 inhibitor because of the gradually increasing levels of acute phase reactants identified on serial blood draws, as well as his declining respiratory status. The treatment was well-tolerated in conjunction with standard drug therapies for COVID-19 (hydroxychloroquine, azithromycin, and zinc). The patient subsequently experienced marked improvements in his respiratory symptoms and overall clinical status over the following days. We believe that tocilizumab played a substantial role in his ability to avert clinical decline, particularly the need for mechanical ventilation. Ultimately, the patient was downgraded from the ICU and discharged within days. We highlight the potential of IL-6 inhibitors to prevent the progression of respiratory disease to a point requiring ventilator support. This case underscores the potential importance of early serial measurements of IL-6 and cytokine storm-associated acute phase reactants, such as ferritin, D-dimer, and C-reactive protein, in guiding clinical decision-making in the management of patients with suspected COVID-19. Conclusion: The early, proactive identification of serum acute phase reactants should be implemented in the treatment of COVID-19 in order to screen for a primary contributor to mortality—the cytokine storm. This screening, when followed by aggressive early treatment for cytokine storm, may have optimal therapeutic benefits and obviate the need for mechanical ventilation, thereby decreasing mortality. Additionally, we review current evidence regarding cytokine release syndrome in COVID-19 and the use of IL-6 receptor inhibition as a therapeutic strategy, and examine other reported cases in the literature describing IL-6 antagonist treatment for patients with COVID-19.

Adoptive T cell immunotherapy can cause regression of established malignancy. One promising approach is to transfer genes encoding chimeric antigen receptors (CARs) that specifically recognize tumor-associated antigens to T cells before the T cells are adoptively transferred to patients. We have constructed a CAR that consists of an anti-CD19 single chain variable region (scFv) that is coupled to a portion of the CD28 costimulatory molecule and the signaling component of the CD3-zeta chain. CD19 is a promising target for immunotherapy because most malignant B cell express CD19, but the only normal cells that express CD19 are B cells, B cell precursors, and perhaps follicular dendritic cells. We have demonstrated that gamma-retroviruses encoding the anti-CD19 CAR can be used to transduce human T cells and that these transduced T cells specifically recognize CD19+ targets. To transduce T cells, we stimulated T cells with the anti-CD3 monoclonal antibody OKT3 on day 0 then conducted sequential retroviral transductions on day 2 and on day 3. Transductions were performed by spin-loading retroviruses onto RetroNectin (Takara) coated culture plates followed by overnight incubation of the OKT3- stimulated T cells on the plates. Forty-five to sixty-seven percent of T cells expressed the anti-CD19 CAR as measured by flow cytometry 7–8 days after transduction (n=8). Anti-CD19-CAR-transduced CD8+ and CD4+ T cells produced IFNg and IL-2 specifically in response to stimulation with CD19+ target cells. The transduced T cells specifically killed primary chronic lymphocytic leukemia (CLL) cells. T cells from CLL patients that were either untreated or previously treated with fludarabine plus rituximab could be transduced and induced to proliferate sufficiently to provide enough cells for clinical adoptive T cell transfer. In addition, we adapted this protocol for use in CLL patients with very high peripheral blood leukemia cell counts by depleting CD19+ cells using magnetic bead sorting prior to OKT3 stimulation. In preparation for a clinical trial that will enroll patients with advanced B cell malignancies, we have generated a producer cell clone that produces GALV (Gibbon ape leukemia virus)-enveloped gamma-retroviruses encoding the anti-CD19 CAR, and we have produced sufficient retroviral supernatant for the proposed clinical trial under good manufacturing practice (GMP) conditions.

Background Brachial plexopathy causes pain and loss of function in the affected extremity. Entrapment of the brachial plexus terminal branches within the surrounding connective tissue, or medial brachial fascial compartment, may manifest in debilitating symptoms. Open fasciotomy and external neurolysis of the neurovascular bundle in the medial brachial fascial compartment were performed as a surgical treatment for pain and functional decline in the upper extremity. The aim of this study was to evaluate pain outcomes after surgery in patients diagnosed with brachial plexopathy. Methods We identified 21 patients who met inclusion criteria. Documents dated between 2005 and 2019 were reviewed from electronic medical records. Chart review was conducted to collect data on visual analog scale (VAS) for pain, Semmes-Weinstein monofilament test (SWMT), and Medical Research Council (MRC) scale for muscle strength. Pre- and postoperative data was obtained. A paired sample t-test was used to determine statistical significance of pain outcomes. Results Pain severity in the affected arm was significantly reduced after surgery (pre: 6.4 ± 2.5; post: 2.0 ± 2.5; p < 0.01). Additionally, there was an increased response to SWMT after the procedure. More patients achieved an MRC rating score ≥3 and ≥4 in elbow flexion after surgery. This may be indicative of improved sensory and motor function. Conclusion Open fasciotomy and external neurolysis at the medial brachial fascial compartment is an effective treatment for pain when nerve continuity is preserved. These benefits were evident in patients with a prolonged duration elapsed since injury onset.

Patient: Male, 66-year-old Final Diagnosis: Guillain-Barré syndrome Symptoms: Paresthesia • weakness Medication: — Clinical Procedure: — Specialty: Immunology • Infectious Diseases • Neurology • Rehabilitation Objective: Unknown etiology Background: Since December 2020, multiple vaccines have mobilized mass immunization campaigns capable of mitigating the current SARS-COV-2 pandemic. Ad26.COV2.S (Johnson & Johnson/Janssen) is a recombinant, replication-incompetent vector vaccine encoding the SARS-CoV-2 spike (s) protein and is especially protective against severe-critical disease. It is a single-dose injection; adverse effects after vaccine administration are usually mild and self-limited, including pain at the injection site, headache, fatigue, muscle aches, and nausea. Severe adverse events involving hospitalization and death after Ad26.COV2.S rarely occur. However, not unlike previous viral vector vaccines, ongoing clinical trials may unveil rare complications of Ad26.COV2.S. Guillain-Barré syndrome (GBS) is an autoimmune demyelinating polyneuropathy that can potentially manifest severe neurological symptoms after vaccination. Case Report: This report describes a case of classic GBS features that manifested 14 days after a single Ad26.COV2.S vaccine injection. The patient developed flaccid paralysis with treatment-related fluctuations. Our findings warrant further investigation into the potential relationship between SARS-CoV-2 vaccinations and the development of GBS. Conclusions: A temporal association between the Ad26.COV2.S (Johnson & Johnson/Janssen) vaccine and the onset of GBS was demonstrated in this case report. A feasible underlying pathogenic mechanism involves the cross-reactivity of antibodies stimulated by adenovirus vaccine components and peripheral nerve glycoproteins. However, there is currently insufficient evidence to support a causal relationship between Ad26.COV2.S and the development of GBS. Further evidence gathered from clinician surveillance and clinical trials are needed to draw these conclusions.

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