James D. Geiger

Profiling Changes in Gene Expression during Differentiation and Maturation of Monocyte-derived Dendritic Cells Using Both Oligonucleotide Microarrays and Proteomics*

Dendritic cells (DCs) are antigen-presenting cells that play a major role in initiating primary immune responses. We have utilized two independent approaches, DNA microarrays and proteomics, to analyze the expression profile of human CD14+ blood monocytes and their derived DCs. Analysis of gene expression changes at the RNA level using oligonucleotide microarrays complementary to 6300 human genes showed that ∼40% of the genes were expressed in DCs. A total of 255 genes (4%) were found to be regulated during DC differentiation or maturation. Most of these genes were not previously associated with DCs and included genes encoding secreted proteins as well as genes involved in cell adhesion, signaling, and lipid metabolism. Protein analysis of the same cell populations was done using two-dimensional gel electrophoresis. A total of 900 distinct protein spots were included, and 4% of them exhibited quantitative changes during DC differentiation and maturation. Differentially expressed proteins were identified by mass spectrometry and found to represent proteins with Ca2+ binding, fatty acid binding, or chaperone activities as well as proteins involved in cell motility. In addition, proteomic analysis provided an assessment of post-translational modifications. The chaperone protein, calreticulin, was found to undergo cleavage, yielding a novel form. The combined oligonucleotide microarray and proteomic approaches have uncovered novel genes associated with DC differentiation and maturation and has allowed analysis of post-translational modifications of specific proteins as part of these processes.

The atypical Spitz tumor of uncertain biologic potential

Atypical Spitz tumors (AST) are rare spitzoid melanocytic proliferations with an uncertain malignant potential. ASTs have overlapping features of both Spitz nevi and spitzoid melanoma, and consequently generate controversy with diagnosis and management. Sentinel lymph node biopsy (SLNB) has been proposed as a possible means to gain additional insight into the true biologic potential of these tumors; however, previous reports on the use of SLNB in ASTs have been limited by small numbers of patients and short durations of follow‐up.

Treatment of solid tumours in children with tumour-lysate-pulsed dendritic cells

Dendritic cells are potent stimulators of antigen-specific immune responses, including antitumour responses. We explored the use of tumour-lysate-pulsed dendritic cells in children with relapsed solid tumours. Dendritic cell treatment in children was feasible and apparently not toxic. The treatment was able to produce significant tumour regression in a child with metastatic fibrosarcoma.

The Kasai portoenterostomy for biliary atresia: a review of a 27-year experience with 81 patients

PURPOSE The aim of this study was to utilize clinical outcome methodology through multivariable analysis of perioperative factors to predict a successful Kasai-portoenterostomy (PE). METHODS Records of 81 patients treated for biliary atresia (BA) were reviewed. Outcome was defined as successful if the patient was alive and had no liver transplant (LT). To predict future successful or failed PE, patients were categorized at 6 months post-PE into 2 groups: Success: direct bilirubin (DB) less than 2.0 mg/dL; Failure: DB greater than 2 mg/dL, or the patient was listed/had undergone LT, or had died. Groups were analyzed for positive or negative predictive values (PPV, NPV) at 2 and 5 years after PE. Cox regression was used to determine risk factors for PE. RESULTS PE was successful in 38% and failed in 62%. PPV of future success was 96% at 2 years post-PE and 95% at 5 years post-PE, NPV of failure was 76% and 74%, respectively. Bridging liver fibrosis at the time of PE and postoperative cholangitic episodes were interdependent risk factors for a failed PE (P <.05). Other covariates showed no significant relationship for PE outcome. CONCLUSION Classifying of patients 6 months postoperatively allowed us to determine a successful PE outcome. Bridging liver fibrosis at the time of the Kasai, and the increased number of postoperative cholangitic episodes were predictive of a poor PE outcome.

Conservative management of mesenchymal hamartoma of the liver

The natural history of mesenchymal hamartoma of the liver is poorly understood. This case demonstrates the course of a biopsy-proven mesenchymal hamartoma using sequential computed tomography (CT) examinations. These CT scans show initial expansion of the lesion with subsequent involution. The spontaneous resolution in this patient suggests the possibility of conservative management of asymptomatic mesenchymal hamartomas. The case is presented, and the literature on mesenchymal hamartoma is reviewed.

A prospective study of expectant observation as primary therapy for neuroblastoma in young infants: A children's oncology group study

Objective:To demonstrate that expectant observation of young infants with small adrenal masses would result in excellent event-free and overall survival. Background:Neuroblastoma is the most common malignant tumor in infants, and in young infants, 90% of neuroblastomas are located in the adrenal gland. Although surgical resection is standard therapy, multiple observations suggest that expectant observation could be a safe alternative for infants younger than 6 months who have small adrenal masses. Methods:A prospective study of infants younger than 6 months with small adrenal masses and no evidence of spreading beyond the primary tumor was performed at participating Childrens Oncology Group institutions. Parents could choose observation or immediate surgical resection. Serial abdominal sonograms and urinary vanillylmandelic acid and homovanillic acid measurements were performed during a 90-week interval. Infants experiencing a 50% increase in the volume of the mass, urine catecholamine values, or an increase in the homovanillic acid to vanillylmandelic acid ratio greater than 2, were referred for surgical resection. Results:Eighty-seven eligible patients were enrolled: 83 elected observation and 4 chose immediate surgery. Sixteen observational patients ultimately had surgery; 8 had International Neuroblastoma Staging System stage 1 neuroblastoma, 2 had higher staged neuroblastoma (2B and 4S), 2 had low-grade adrenocortical neoplasm, 2 had adrenal hemorrhage, and 2 had extralobar pulmonary sequestration. The 2 patients with adrenocortical tumors were resected because of a more than 50% increase in tumor volume. The 3-year event-free survival for a neuroblastoma event was 97.7 ± 2.2% within the entire cohort of patients (n = 87). The 3-year overall survival was 100%, with a median follow-up of 3.2 years. Eighty-one percent of patients on the observation arm were spared resection. Conclusions:Expectant observation of infants younger than 6 months with small adrenal masses led to excellent event-free survival and overall survival while avoiding surgical intervention in a large majority of the patients.

Gastric Transposition for Esophageal Replacement in Children: Experience With 41 Consecutive Cases With Special Emphasis on Esophageal Atresia

ObjectiveTo evaluate the authors’ experience with gastric transposition as a method of esophageal replacement in children with congenital or acquired abnormalities of the esophagus. Summary Background DataEsophageal replacement in children is almost always done for benign disease and thus requires a conduit that will last more than 70 years. The organ most commonly used in the past has been colon; however, most series have been fraught with major complications and conduit loss. For these reasons, in 1985 the authors switched from using colon interpositions to gastric transpositions for esophageal replacement in infants and children. MethodsThe authors retrospectively reviewed the records of 41 patients with the diagnoses of esophageal atresia (n = 26), corrosive injury (n = 8), leiomyomatosis (n = 5), and refractory gastroesophageal reflux (n = 2) who underwent gastric transposition for esophageal replacement. ResultsMean ± SE age at the time of gastric transposition was 3.3 ± 0.6 years. All but two transpositions were performed through the posterior mediastinum without mortality or loss of the gastric conduit despite previous surgery on the gastric fundus in 8 (20%), previous esophageal operations in 15 (37%), and previous esophageal perforations in 6 (15%) patients. Complications included esophagogastric anastomotic leak (n = 15, 36%), which uniformly resolved without intervention; stricture formation (n = 20, 49%), all of which no longer require dilation; and feeding intolerance necessitating jejunal feeding (n = 8, 20%) due to delayed gastric emptying (n = 3), feeding aversion related to the underlying anomaly (n = 1), or severe neurological impairment (n = 4). No redo anastomoses were required. ConclusionsGastric transposition reestablishes effective gastrointestinal continuity with few complications. Oral feeding and appropriate weight gain are achieved in most children. Therefore, gastric transposition is an appropriate alternative for esophageal replacement in infants and children.

Use of Cholecystokinin to Prevent the Development of Parenteral Nutrition-Associated Cholestasis

BACKGROUND Neonates are at high risk for the development of parenteral nutrition-associated cholestasis when receiving a prolonged course of total parenteral nutrition (TPN). Although this cholestasis is of unknown etiology, it may result from a lack of gastrointestinal hormone formation, including cholecystokinin, which normally occurs after enteral feedings. METHODS Two groups of neonates were studied. The treatment group consisted of 21 consecutive, prospectively enlisted neonates receiving TPN for > 14 days. The nontreatment group consisted of 21 infants from the 2 years preceding the study who were matched to the treatment group by gestational age, diagnosis, and duration of TPN. The major outcome determinant was direct bilirubin. Cholestasis was defined as a direct bilirubin > 2.0 mg/dL and was considered severe if the direct bilirubin was > 5.0 mg/dL after other causes were ruled out. RESULTS The mean direct bilirubin levels in the nontreated group progressively rose over time, whereas the mean direct bilirubin the treated group remained level. The incidence of infants with a direct bilirubin > 2.0 mg/dL was 24% and 43% in the CCK+ and CCK- groups, respectively, and was not significant (p = .14). The percentage of infants with a direct bilirubin > 5.0 mg/dL was 9.5% and 38% in the treatment and nontreatment groups, respectively, and was significant, p = .015. CONCLUSIONS Levels of direct bilirubin were lower in the treated compared with the nontreated group. These findings suggest that cholecystokinin prophylaxis in high-risk neonates may help prevent the development of parenteral nutrition-associated cholestasis.

Generation of T-cells reactive to the poorly immunogenic B16-BL6 melanoma with efficacy in the treatment of spontaneous metastases

The B16-BL6 (BL6) melanoma is a poorly immunogenic murine tumor that is highly invasive and spontaneously metastasizes from the primary site. Utilizing an established anti-CD3/interleukin-2 (IL-2) culture procedure, we have previously reported that lymph nodes (LNs) draining immunogenic murine sarcomas contained preeffector cells that could be activated to differentiate into therapeutic effector cells for adoptive immunotherapy. By contrast, LNs draining the poorly immunogenic BL6 melanoma were found not to be a reliable source of preeffector cells. Instead, sensitization of preeffector cells reactive to BL6 required the subcutaneous inoculation of tumor admixed with Corynebacterium parvum. LN cells draining these vaccination sites demonstrated therapeutic efficacy only after subsequent anti-CD3/IL-2 activation. The sensitization of preeffector cells was dependent on the presence of tumor antigen and an optimal dose of C. parvum (< or = 50 micrograms). Furthermore, kinetic analysis revealed that the preeffector response was transient after tumor vaccination. The therapeutic efficacy of anti-CD3/IL-2 activated LN cells was further evaluated in the treatment of spontaneous macroscopic BL6 visceral metastases. Spontaneous visceral metastases were induced in animals by inoculation with BL6 tumor in the footpad followed by amputation of the primary tumor 3 weeks later. The systemic transfer of 10(8) anti-CD3/IL-2 activated T-cells and the concomitant intraperitoneal administration of subtherapeutic doses of IL-2 1 week after amputation cured 50% of the animals and prolonged median survival time (MST) to > 140 days. All mice except one that received no treatment or was treated with IL-2 alone succumbed to visceral metastases with an MST of approximately 23 days. This study characterizes a model whereby the weak immune response to the BL6 melanoma can be positively or negatively modulated for the generation of antitumor reactive T-cells useful in adoptive immunotherapy.

Recurrence after laparoscopic and open Nissen fundoplication

Background: Laparoscopic Nissen fundoplication as treatment for gastroesophageal reflux disease (GERD) in adults has a reported recurrence rate of 2–17%. We investigated the rates and mechanisms of failure after laparoscopic Nissen fundoplication in children. Methods: All patients who underwent a laparoscopic Nissen fundoplication for GERD and who subsequently required a redo Nissen were reviewed (n = 15). The control group consisted of the most recent 15 patients who developed recurrent GER after an open Nissen, fundoplication. Results: Between 1994 and 2000, laparoscopic Nissen fundoplication was performed in 179 patients. Fifteen patients (8.7%) underwent revision. The mechanisms of failure were herniation in four patients, wrap dehiscence in four, a too-short wrap in three, a loosened wrap in two, and other reasons in two. The reoperation was performed laparoscopically in five patients (33%). The failure mechanisms were different in the open patients: eight were due to slipped wraps; three to dehiscences; and two to herniations. Conclusion: The failure rate after laparoscopic Nissen is acceptably low. A redo laparoscopic Nissen can be performed safely after an initial laparoscopic approach.