A toxicology study of Csf2ra complementation and pulmonary macrophage transplantation therapy of hereditary PAP in mice

Pulmonary macrophage transplantation (PMT) is a gene and cell transplantation approach in development as therapy for hereditary pulmonary alveolar proteinosis (hPAP), a surfactant accumulation disorder caused by mutations in CSF2RA/B (and murine homologs). We conducted a toxicology study of PMT of Csf2ra gene-corrected macrophages (mGM-Rα+Mϕs) or saline-control intervention in Csf2raKO or wild-type (WT) mice including single ascending dose and repeat ascending dose studies evaluating safety, tolerability, pharmacokinetics, and pharmacodynamics. Lentiviral-mediated Csf2ra cDNA transfer restored GM-CSF signaling in mGM-Rα+Mϕs. Following PMT, mGM-Rα+Mϕs engrafted, remained within the lungs, and did not undergo uncontrolled proliferation or result in bronchospasm, pulmonary function abnormalities, pulmonary or systemic inflammation, anti-transgene product antibodies, or pulmonary fibrosis. Aggressive male fighting caused a similarly low rate of serious adverse events in saline- and PMT-treated mice. Transient, minor pulmonary neutrophilia and exacerbation of pre-existing hPAP-related lymphocytosis were observed 14 days after PMT of the safety margin dose but not the target dose (5,000,000 or 500,000 mGM-Rα+Mϕs, respectively) and only in Csf2raKO mice but not in WT mice. PMT reduced lung disease severity in Csf2raKO mice. Results indicate PMT of mGM-Rα+Mϕs was safe, well tolerated, and therapeutically efficacious in Csf2raKO mice, and established a no adverse effect level and 10-fold safety margin.

Interdigitating Dendritic Cell Sarcoma of the Small Intestine Presenting as Spontaneous Hemoperitoneum - A Rare Case Report

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm arising from the antigen-presenting cells of the immune system. It usually involves the lymph nodes, and extranodal sites are rarely affected. Here, we report a first known case of spontaneous hemoperitoneum caused by the rupture of IDCS of the small bowel. A 61-year-old male presented with complaints of abdominal pain and fever for 3 days and breathlessness for 1 day. Ultrasound abdomen revealed a 15 cm × 7 cm heterogeneous collection with thick septations in the periumbilical region. Diagnostic peritoneal lavage revealed hemoperitoneum and gangrenous bowel. Emergency laprotomy was done and it revealed a friable mass arising from the ileum. Resection of 2 ft of the ileum and double-barrel ileostomy was done. Immunohistochemical analysis revealed a positivity of S100 and leukocyte common antigen). A diagnosis of IDCS was made. The patient had an uneventful postoperative recovery and planned for postoperative chemotherapy.

VPS4A Mutations in Humans Cause Syndromic Congenital Dyserythropoietic Anemia due to Cytokinesis and Trafficking Defects

The Congenital Dyserythropoietic Anemia (CDA) Registry was established with the goal to facilitate investigations of natural history, biology, and molecular pathogenetic mechanisms of CDA. Three unrelated individuals enrolled in the registry had a syndrome characterized by CDA and severe neurodevelopmental delay. They were found to have missense mutations in VPS4A, a gene coding for an ATPase that regulates the ESCRT-III machinery in a variety of cellular processes including cell division, endosomal vesicle trafficking, and viral budding. Bone marrow studies showed binucleated erythroblasts and erythroblasts with cytoplasmic bridges indicating abnormal cytokinesis and abscission. Circulating red blood cells were found to retain transferrin receptor (CD71) in their membrane, demonstrating that VPS4A is critical for normal reticulocyte maturation. Using proband-derived induced pluripotent stem cells (iPSCs), we have successfully modeled the hematologic aspects of this syndrome in vitro, recapitulating their dyserythropoietic phenotype. Our findings demonstrate that VPS4A mutations cause cytokinesis and trafficking defects leading to a human disease with detrimental effects to erythropoiesis and neurodevelopment.

The Spectrum of SPTA1-Associated Hereditary Spherocytosis

Hereditary spherocytosis (HS) is the most common red blood cell (RBC) membrane disorder causing hereditary hemolytic anemia. Patients with HS have defects in the genes coding for ankyrin (ANK1), band 3 (SLC4A1), protein 4.2 (EPB42), and α (SPTA1) or β-spectrin (SPTB). Severe recessive HS is most commonly due to biallelic SPTA1 mutations. α-spectrin is produced in excess in normal erythroid cells, therefore SPTA1-associated HS ensues with mutations causing significant decrease of normal protein expression from both alleles. In this study, we systematically compared genetic, rheological, and protein expression data to the varying clinical presentation in eleven patients with SPTA1-associated HS. The phenotype of HS in this group of patients ranged from moderately severe to severe transfusion-dependent anemia and up to hydrops fetalis which is typically fatal if transfusions are not initiated before term delivery. The pathogenicity of the mutations could be corroborated by reduced SPTA1 mRNA expression in the patients’ reticulocytes. The disease severity correlated to the level of α-spectrin protein in their RBC cytoskeleton but was also affected by other factors. Patients carrying the low expression α^LEPRA allele in trans to a null SPTA1 mutation were not all transfusion dependent and their anemia improved or resolved with partial or total splenectomy, respectively. In contrast, patients with near-complete or complete α-spectrin deficiency have a history of having been salvaged from fatal hydrops fetalis, either because they were born prematurely and started transfusions early or because they had intrauterine transfusions. They have suboptimal reticulocytosis or reticulocytopenia and remain transfusion dependent even after splenectomy; these patients require either lifetime transfusions and iron chelation or stem cell transplant. Comprehensive genetic and phenotypic evaluation is critical to provide accurate diagnosis in patients with SPTA1-associated HS and guide toward appropriate management.

Comparison of Endoscopic Variceal Ligation with Endoscopic Sclerotherapy for Secondary Prophylaxis of Variceal Hemorrhage: A Randomized Trial

Background

Though endoscopic variceal ligation (EVL) is commonly being used and has overcome the disadvantages of sclerotherapy (ST), still sclerotherapy is used as a therapeutic procedure for bleeding esophageal varices in the present institute. Hence, the study was done to see the advantages of EVL over ST.

Methods

Patients with portal hypertension and bleeding esophageal varices underwent banding if found to have grade 3 or 4 varices. They were randomized to EVL group, where they were reviewed after two weeks for any residual varices for which repeat banding was done and endoscopic sclerotherapy (EST) group, where ST was done until the varices were obliterated or reduced to grade 1. The efficacy, complications, recurrent bleeding rate and recurrence of varices were compared.

Results

A total of 60 patients were included, 30 in each group. In EVL group, four sessions were needed to eradicate the varices in 73% of patients while it was five sessions in EST group (46% patients) (p-value = 0.0001). The mean number of sessions needed in EVL and EST group was 3.73 and 5.36, respectively. The average time taken for eradication of varices was 78.6 and 134.6 days in EVL and EST group, respectively (p-value = 0.004). Complications were higher in EST group (p-value < 0.05).

Conclusion

EVL alone was effective than ST in terms of the number of sessions needed for eradication of varices and total duration required to completely obliterate them. The complications were less in EVL group with no significant difference in recurrent bleeding rate and recurrence of varices between the groups.

A Surgical Conundrum in Feeding Jejunostomy-Jejunojejunal Intussusception: A Case Series

Intussusception is a common cause of intestinal obstruction in the pediatric population. Usually, it is primary and benign and can be managed by nonoperative interventions in 80% of the cases. Adult intussusception accounts for only 5% of all cases of intussusception and 1%–5% of all cases of intestinal obstruction. Unlike in the pediatric population, intussusception in adults is usually caused by a pathologic lead point. The initial investigation to diagnose it is an ultrasound abdomen followed by contrast-enhanced computed tomography (CECT) of the abdomen. The placement of an intestinal tube for feeding purposes has been rarely reported as a cause of intussusception. Here, we present a case series of four patients who had jejunojejunal intussusception following the placement of feeding tubes into the jejunum. Three patients were operatively managed and one was managed conservatively.