Uncovering cryptic glycan markers in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE).

Using an integrated antigen microarray approach, we observed epitope-spreading of autoantibody responses to a variety of antigenic structures in the cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) and in the serum of mice with experimental autoimmune encephalomyelitis (EAE). These included previously described protein- and lipid-based antigenic targets and newly discovered autoimmunogenic sugar moieties, notably, autoantibodies specific for the oligomannoses in both MS patient CSF and the sera of mice with EAE. These glycans are often masked by other sugar moieties and belong to a class of cryptic autoantigens. We further determined that these targets are highly expressed on multiple cell types in MS and EAE lesions. Co-immunization of SJL/J mice with a Man9-KLH conjugate at the time of EAE induction elicited highly significant levels of anti-Man9-cluster autoantibodies. Nevertheless, this anti-glycan autoantibody response was associated with a significantly reduced clinical severity of EAE. The potential of these cryptic glycan markers and targeting antibodies for diagnostic and therapeutic interventions of neurological disorders has yet to be explored.

Vulnerability and Colorectal screening during the pandemic.

Objective: Disparities in colorectal cancer (CRC) screening prevalence across United States neighborhoods may reflect social inequities that create barriers to accessing and completing preventive health services. Our objective was to identify whether neighborhood social vulnerability was associated with a change in CRC screening prevalence in Boston neighborhoods during the COVID-19 pandemic. Methods: Adults ages 50-74 years due for CRC screening who received primary care at one of 35 primary care practices affiliated with Massachusetts General Hospital or Brigham and Women's Hospital (Boston, MA), 3/1/2020 to 3/1/2022. The Social Vulnerability Index (SVI) is an aggregate measure of neighborhood social factors often used by public health authorities to examine neighborhood susceptibility to many health outcomes. Results: In 2020, 74.9 % of eligible individuals were up to date with CRC screening and this fell to 67.4 % in 2022 (p < 0.001). In 2020, 36.2 % of eligible patients lived in a neighborhood above the 80th percentile of SVI, consistent with high social vulnerability, while the same value was 35.1 % in 2022. There was no association between the change in screening prevalence and SVI: a decrease of 5.5 % screened in neighborhoods with SVI ≤ 80 compared to a decrease of 3.6 % in neighborhoods with SVI > 80 (p = 0.79). Conclusions: The COVID-19 pandemic equalized the prevalence of CRC screening across Boston-area neighborhoods despite pre-existing geographic disparities in screening prevalence and SVI. Strategies to ensure equitable participation in CRC screening to promote health equity should be considered to promote equitable pandemic recovery.

Piet Mondrian's trees and the evolution in understanding multiple sclerosis, Charcot Prize Lecture 2011.

Four questions were posed about multiple sclerosis (MS) at the 2011 Charcot Lecture, Oct. 22, 2011. 1. The Male/Female Disparity: Why are women developing MS so much more frequently than men? 2. Neuronal and Glial Protection: Are there guardian molecules that protect the nervous system in MS? 3. Predictive Medicine: With all the approved drugs, how can we rationally decide which one to use? 4. The Precise Scalpel vs. the Big Hammer for Therapy: Is antigen-specific therapy for demyelinating disease possible? To emphasize how our views on the pathogenesis and treatment of MS are evolving, and given the location of the talk in Amsterdam, Piet Mondrian's progressive interpretations of trees serve as a heuristic.

Inhibitory role for GABA in autoimmune inflammation.

GABA, the principal inhibitory neurotransmitter in the adult brain, has a parallel inhibitory role in the immune system. We demonstrate that immune cells synthesize GABA and have the machinery for GABA catabolism. Antigen-presenting cells (APCs) express functional GABA receptors and respond electrophysiologically to GABA. Thus, the immune system harbors all of the necessary constituents for GABA signaling, and GABA itself may function as a paracrine or autocrine factor. These observations led us to ask further whether manipulation of the GABA pathway influences an animal model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Increasing GABAergic activity ameliorates ongoing paralysis in EAE via inhibition of inflammation. GABAergic agents act directly on APCs, decreasing MAPK signals and diminishing subsequent adaptive inflammatory responses to myelin proteins.

Blocking angiotensin-converting enzyme induces potent regulatory T cells and modulates TH1- and TH17-mediated autoimmunity.

The renin-angiotensin-aldosterone system (RAAS) is a major regulator of blood pressure. The octapeptide angiotensin II (AII) is proteolytically processed from the decapeptide AI by angiotensin-converting enzyme (ACE), and then acts via angiotensin type 1 and type 2 receptors (AT1R and AT2R). Inhibitors of ACE and antagonists of the AT1R are used in the treatment of hypertension, myocardial infarction, and stroke. We now show that the RAAS also plays a major role in autoimmunity, exemplified by multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Using proteomics, we observed that RAAS is up-regulated in brain lesions of MS. AT1R was induced in myelin-specific CD4+ T cells and monocytes during autoimmune neuroinflammation. Blocking AII production with ACE inhibitors or inhibiting AII signaling with AT1R blockers suppressed autoreactive TH1 and TH17 cells and promoted antigen-specific CD4+FoxP3+ regulatory T cells (Treg cells) with inhibition of the canonical NF-kappaB1 transcription factor complex and activation of the alternative NF-kappaB2 pathway. Treatment with ACE inhibitors induces abundant CD4+FoxP3+ T cells with sufficient potency to reverse paralytic EAE. Modulation of the RAAS with inexpensive, safe pharmaceuticals used by millions worldwide is an attractive therapeutic strategy for application to human autoimmune diseases.

Magnetic resonance imaging criteria of immune checkpoint inhibitor-induced hypophysitis.

Autoimmune hypophysitis is a rare complication of immune checkpoint inhibitors. Immune checkpoint inhibitors have been used for advanced stages of melanoma, renal cell carcinoma, and lung cancer. Multiple endocrinopathies, among them hypophysitis, could result as a reverse event from this therapy. MRI is the imaging modality of choice and usually demonstrates pituitary gland hypertrophy, irregular thickening of the pituitary infundibulum, and diffuse enhancement. We present a case of stage IV metastatic renal cell carcinoma complicated with hypophysitis secondary to combined nivolumab and ipilimumab therapy.

Activity Within an Extraperitoneal Ureteral Herniation Detected on Bone Scan, Associated With a Partially Duplicated Collecting System.

A 64-year-old man with history of renal stones and prostate cancer presented for evaluation of osseous metastatic disease due to elevated prostate-specific antigen (13.7 ng/mL). A Tc-labeled bone scan demonstrated unusual linear uptake projecting over the lower pelvis extending into the scrotum. Follow-up CT confirmed a rare case of inguinoscrotal extraperitoneal herniation of the ureter associated with a partially duplicated left renal collecting system. The left-sided inguinoscrotal uptake was within the herniated ureter, potentially mimicking disease within the pelvis.

Spotlight on the pediatric eye: a pictorial review of orbital anatomy and congenital orbital pathologies.

Orbital lesions in the pediatric population vary from adults in terms of their presentation, unique pathology, and imaging characteristics. The prompt and accurate diagnosis of these lesions is imperative to prevent serious consequences in terms of visual impairment and disfigurement. Along with dedicated ophthalmologic examination, imaging is instrumental in characterizing these lesions, both for accurate diagnosis and subsequent management. In our pictorial essay, we provide a basic review of orbital embryology, anatomy, and congenital orbital pathologies, with emphasis on radiological findings.

Spontaneous hemorrhage of an adrenal myelolipoma treated with transarterial embolization: A case report.

Adrenal myelolipoma is a benign tumor of the adrenal cortex composed predominantly of fat and hematopoietic tissue. These lesions are usually asymptomatic, and most often incidentally detected on imaging. Uncommonly, they present with retroperitoneal hemorrhage, and these have been traditionally treated with emergent surgery. Although, transarterial embolization has been effectively and safely used in patients presenting with active hemorrhage from acute traumatic and nontraumatic causes, literature specifically pertaining to adrenal artery embolization is scant, perhaps due to smaller size and variability of adrenal arteries. With recent advances in endovascular techniques and imaging, there are emerging case reports and series of adrenal artery embolization in acute and nonacute settings. We report a case of spontaneous hemorrhage within an adrenal myelolipoma in a 43-year-old male patient, successfully treated with transarterial embolization, thereby avoiding major surgery. Our report adds to the growing body of literature pertaining to adrenal artery embolization.

Appendiceal diverticulosis in a patient with family history of Birt-Hogg-Dubé syndrome--a case report.

Birt-Hogg-Dubé syndrome (BHD) is a rare autosomal dominant disorder that predisposes patients to cutaneous tumors, pulmonary cysts with recurrent spontaneous pneumothoraces, and a variety of renal neoplasms including hybrid oncocytic and chromophobe renal cell carcinomas. There has been much debate regarding the genetic link with the occurrence of colorectal cancer and other colonic anomalies. Associations between BHD and intestinal adenomatous polyposis and sigmoid diverticulosis have been described in the literature, but there have been no prior reports of appendiceal diverticulosis in patients with BHD. Here, we present a 40-year-old female patient with a known family history of BHD, who was found to have diverticulosis of the appendix and pulmonary blebs on computed tomography upon routine screening for renal and pulmonary abnormalities, suggesting additional focus be given to the gastrointestinal tract (including the appendix) at the time of CT assessment.

Chest Imaging in Patients Hospitalized With COVID-19 Infection - A Case Series.

COVID-19 (Corona Virus Disease-19) is a zoonotic illness first reported in the city of Wuhan, China in December 2019, and is now officially a global pandemic as declared by the World Health Organization. The infection is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 infected patients can be asymptomatic carriers or present with mild-to-severe respiratory symptoms. Imaging, including computed tomography is not recommended to screen/diagnose COVID-19 infections, but plays an important role in management of these patients, and to rule out alternative diagnoses or coexistent diseases. In our multicenter case series, we outline the clinical presentations and illustrate the most common imaging manifestations in patients hospitalized with COVID-19.

Metastatic appendiceal cancer treated with Yttrium 90 radioembolization and systemic chemotherapy: A case report.

BACKGROUND: Primary appendiceal cancers are rare, and they generally present with liver and/or peritoneal metastases. Currently there are no guidelines to treat metastatic appendiceal cancer, and hence they are treated as metastatic colorectal cancer. Combining Yttrium 90 (Y-90) radioembolization (RE) with systemic chemotherapy early in the treatment of right sided colon cancers has been shown to improve survival. Based on this data, a combination of systemic chemotherapy and Y-90 RE was used to treat a case of metastatic appendiceal cancer. CASE SUMMARY: A 76-year-old male presented to the emergency room with progressive right lower quadrant pain. A Computed Tomography of the abdomen and pelvis was performed which showed acute appendicitis and contained perforation. Urgent laparoscopic appendectomy was then followed by histological analysis, which was significant for appendiceal adenocarcinoma. After complete workup he underwent right hemicolectomy and lymph node dissection. He received adjuvant chemotherapy as the local lymph nodes were positive. Follow-up imaging was significant for liver metastasis. Due to rapid growth of the liver lesions and new peritoneal nodules, the patient was treated with a combination of Y-90 RE and folinic acid, fluorouracil, and irinotecan with bevacizumab and not microwave ablation as previously planned. Follow up imaging demonstrated complete response of the liver lesions. At 12-mo follow-up, the patient continued to enjoy good quality of life with no recurrent disease. CONCLUSION: Utilization of Y-90 RE concomitantly with systemic chemotherapy early in the treatment of appendiceal cancer may provide improved control of this otherwise aggressive cancer.

Amelioration of ongoing experimental autoimmune encephalomyelitis with fluoxetine.

In patients with multiple sclerosis, the selective serotonin reuptake inhibitor, fluoxetine, resulted in less acute disease activity. We tested the immune modulating effects of fluoxetine in a mouse model of multiple sclerosis, i.e. experimental autoimmune encephalomyelitis (EAE). We show that fluoxetine delayed the onset of disease and reduced clinical paralysis in mice with established disease. Fluoxetine had abrogating effects on proliferation of immune cells and inflammatory cytokine production by both antigen-presenting cells and T cells. Specifically, in CD4 T cells, fluoxetine increased Fas-induced apoptosis. We conclude that fluoxetine possesses immune-modulating effects resulting in the amelioration of symptoms in EAE.

Peroxisome proliferator-activated receptor delta limits the expansion of pathogenic Th cells during central nervous system autoimmunity.

Peroxisome proliferator-activated receptors (PPARs; PPAR-alpha, PPAR-delta, and PPAR-gamma) comprise a family of nuclear receptors that sense fatty acid levels and translate this information into altered gene transcription. Previously, it was reported that treatment of mice with a synthetic ligand activator of PPAR-delta, GW0742, ameliorates experimental autoimmune encephalomyelitis (EAE), indicating a possible role for this nuclear receptor in the control of central nervous system (CNS) autoimmune inflammation. We show that mice deficient in PPAR-delta (PPAR-delta(-/-)) develop a severe inflammatory response during EAE characterized by a striking accumulation of IFN-gamma(+)IL-17A(-) and IFN-gamma(+)IL-17A(+) CD4(+) cells in the spinal cord. The preferential expansion of these T helper subsets in the CNS of PPAR-delta(-/-) mice occurred as a result of a constellation of immune system aberrations that included higher CD4(+) cell proliferation, cytokine production, and T-bet expression and enhanced expression of IL-12 family cytokines by myeloid cells. We also show that the effect of PPAR-delta in inhibiting the production of IFN-gamma and IL-12 family cytokines is ligand dependent and is observed in both mouse and human immune cells. Collectively, these findings suggest that PPAR-delta serves as an important molecular brake for the control of autoimmune inflammation.

T helper type 1 and 17 cells determine efficacy of interferon-beta in multiple sclerosis and experimental encephalomyelitis.

Interferon-beta (IFN-beta) is the major treatment for multiple sclerosis. However, this treatment is not always effective. Here we have found congruence in outcome between responses to IFN-beta in experimental autoimmune encephalomyelitis (EAE) and relapsing-remitting multiple sclerosis (RRMS). IFN-beta was effective in reducing EAE symptoms induced by T helper type 1 (T(H)1) cells but exacerbated disease induced by T(H)17 cells. Effective treatment in T(H)1-induced EAE correlated with increased interleukin-10 (IL-10) production by splenocytes. In T(H)17-induced disease, the amount of IL-10 was unaltered by treatment, although, unexpectedly, IFN-beta treatment still reduced IL-17 production without benefit. Both inhibition of IL-17 and induction of IL-10 depended on IFN-gamma. In the absence of IFN-gamma signaling, IFN-beta therapy was ineffective in EAE. In RRMS patients, IFN-beta nonresponders had higher IL-17F concentrations in serum compared to responders. Nonresponders had worse disease with more steroid usage and more relapses than did responders. Hence, IFN-beta is proinflammatory in T(H)17-induced EAE. Moreover, a high IL-17F concentration in the serum of people with RRMS is associated with nonresponsiveness to therapy with IFN-beta.

Innate and adaptive autoimmunity directed to the central nervous system.

The immune system has two major components, an innate arm and an adaptive arm. Certain autoimmune diseases of the brain represent examples of disorders where one of these constituents plays a major role. Some rare autoimmune diseases involve activation of the innate arm and include chronic infantile neurologic, cutaneous, articular (CINCA) syndrome. In contrast, adaptive immunity is prominent in multiple sclerosis, neuromyelitis optica, and the paraneoplastic syndromes where highly specific T cell responses and antibodies mediate these diseases. Studies of autoimmune brain disorders have aided in the elucidation of distinct neuronal roles played by key molecules already well known to immunologists (e.g., complement and components of the major histocompatibility complex). In parallel, molecules known to neurobiology and sensory physiology, including toll-like receptors, gamma amino butyric acid and the lens protein alpha B crystallin, have intriguing and distinct functions in the immune system, where they modulate autoimmunity directed to the brain.