Common single-base insertions in the VNTR of the carboxyl ester lipase (CEL) gene are benign and also likely to arise somatically in the exocrine pancreas.

The CEL gene encodes carboxyl ester lipase, a pancreatic digestive enzyme. CEL is extremely polymorphic due to a variable number tandem repeat (VNTR) located in the last exon. Single-base deletions within this VNTR cause the inherited disorder MODY8, whereas little is known about VNTR single-base insertions in pancreatic disease. We therefore mapped CEL insertion variants (CEL-INS) in 200 Norwegian patients with pancreatic neoplastic disorders. Twenty-eight samples (14.0%) carried CEL-INS alleles. Most common were insertions in repeat 9 (9.5%), which always associated with a VNTR length of 13 repeats. The combined INS allele frequency (0.078) was similar to that observed in a control material of 416 subjects (0.075). We performed functional testing in HEK293T cells of a set of CEL-INS variants, in which the insertion site varied from the first to the 12th VNTR repeat. Lipase activity showed little difference among the variants. However, CEL-INS variants with insertions occurring in the most proximal repeats led to protein aggregation and endoplasmic reticulum stress, which upregulated the unfolded protein response. Moreover, by using a CEL-INS-specific antibody, we observed patchy signals in pancreatic tissue from humans without any CEL-INS variant in the germline. Similar pancreatic staining was seen in knock-in mice expressing the most common human CEL VNTR with 16 repeats. CEL-INS proteins may therefore be constantly produced from somatic events in the normal pancreatic parenchyma. This observation along with the high population frequency of CEL-INS alleles strongly suggests that these variants are benign, with a possible exception for insertions in VNTR repeats 1-4.

Precision Medicine in Pancreatic Disease-Knowledge Gaps and Research Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop.

A workshop on research gaps and opportunities for Precision Medicine in Pancreatic Disease was sponsored by the National Institute of Diabetes and Digestive Kidney Diseases on July 24, 2019, in Pittsburgh. The workshop included an overview lecture on precision medicine in cancer and 4 sessions: (1) general considerations for the application of bioinformatics and artificial intelligence; (2) omics, the combination of risk factors and biomarkers; (3) precision imaging; and (4) gaps, barriers, and needs to move from precision to personalized medicine for pancreatic disease. Current precision medicine approaches and tools were reviewed, and participants identified knowledge gaps and research needs that hinder bringing precision medicine to pancreatic diseases. Most critical were (a) multicenter efforts to collect large-scale patient data sets from multiple data streams in the context of environmental and social factors; (b) new information systems that can collect, annotate, and quantify data to inform disease mechanisms; (c) novel prospective clinical trial designs to test and improve therapies; and (d) a framework for measuring and assessing the value of proposed approaches to the health care system. With these advances, precision medicine can identify patients early in the course of their pancreatic disease and prevent progression to chronic or fatal illness.

Functional Pancreatic Sphincter Dysfunction in Children: Recommendations for Diagnosis and Management.

OBJECTIVE: Functional pancreatic sphincter dysfunction (FPSD), previously characterized as pancreatic sphincter of Oddi dysfunction, is a rarely described cause of pancreatitis. Most studies are reported in adults with alcohol or smoking as confounders, which are uncommon risk factors in children. There are no tests to reliably diagnose FPSD in pediatrics and it is unclear to what degree this disorder contributes to childhood pancreatitis. METHODS: We conducted a literature review of the diagnostic and treatment approaches for FPSD, including unique challenges applicable to pediatrics. We identified best practices in the management of children with suspected FPSD and formed a consensus expert opinion. RESULTS: In children with acute recurrent pancreatitis (ARP) or chronic pancreatitis (CP), we recommend that other risk factors, specifically obstructive factors, be ruled out before considering FPSD as the underlying etiology. In children with ARP/CP, FPSD may be the etiology behind a persistently dilated pancreatic duct in the absence of an alternative obstructive process. Endoscopic retrograde cholangiopancreatography with sphincterotomy should be considered in a select group of children with ARP/CP when FPSD is highly suspected and other etiologies have been effectively ruled out. The family and patient should be thoroughly counseled regarding the risks and advantages of endoscopic intervention. Endoscopic retrograde cholangiopancreatography for suspected FPSD should be considered with caution in children with ARP/CP when pancreatic ductal dilatation is absent. CONCLUSIONS: Our consensus expert guidelines provide a uniform approach to the diagnosis and treatment of pediatric FPSD. Further research is necessary to determine the full contribution of FPSD to pediatric pancreatitis.

Accelerating the Drug Delivery Pipeline for Acute and Chronic Pancreatitis: Summary of the Working Group on Drug Development and Trials in Recurrent Acute Pancreatitis at the National Institute of Diabetes and Digestive and Kidney Diseases Workshop.

Recurrent acute pancreatitis (RAP) is a complex clinical syndrome with significant morbidity, unpredictable outcomes, and limited treatment options. The National Institute of Diabetes and Digestive and Kidney Disease sponsored a workshop on July 25, 2018, in Pittsburgh, Pennsylvania, to address research gaps impeding development of effective therapies for pancreatitis. The RAP working group identified challenges to clinical progress using existing definitions, risk assessment, diagnostic and severity criteria, disease trajectories, outcomes, and research methods. Recurrent acute pancreatitis includes all the risk of acute pancreatitis and often progresses to chronic pancreatitis with variable complications of chronic pain, exocrine insufficiency, diabetes, and pancreatic cancer. However, the great variability among individuals with RAP requires better precision in defining the risks, individual episodes, as well as their frequency, pathogenic pathways, and specific outcome measures for each of the systems affected by pancreatic inflammation. Because of disease complexity, few patients are similar enough for traditional studies and methods to conduct clinical trials with small sample sizes are required. The need for genetic testing, biomarker development, and better imaging methods was highlighted. Adaptive and N-of-one study designs, better endpoints, and outcome measures including patient-reported outcomes should considered early in developing future therapeutic trial design and include all stakeholders.

INternational Study Group of Pediatric Pancreatitis: In Search for a CuRE Cohort Study: Design and Rationale for INSPPIRE 2 From the Consortium for the Study of Chronic Pancreatitis, Diabetes, and Pancreatic Cancer.

We created the INternational Study Group of Pediatric Pancreatitis: In Search for a CuRE (INSPPIRE 2) cohort to study the risk factors, natural history, and outcomes of pediatric acute recurrent pancreatitis and chronic pancreatitis (CP). Patient and physician questionnaires collect information on demographics, clinical history, family and social history, and disease outcomes. Health-related quality of life, depression, and anxiety are measured using validated questionnaires. Information entered on paper questionnaires is transferred into a database managed by Consortium for the Study of Chronic Pancreatitis, Diabetes, and Pancreatic Cancer's Coordinating and Data Management Center. Biosamples are collected for DNA isolation and analysis of most common pancreatitis-associated genes.Twenty-two sites (18 in the United States, 2 in Canada, and 1 each in Israel and Australia) are participating in the INSPPIRE 2 study. These sites have enrolled 211 subjects into the INSPPIRE 2 database toward our goal to recruit more than 800 patients in 2 years. The INSPPIRE 2 cohort study is an extension of the INSPPIRE cohort study with a larger and more diverse patient population. Our goals have expanded to include evaluating risk factors for CP, its sequelae, and psychosocial factors associated with pediatric acute recurrent pancreatitis and CP.

Standard Operating Procedures for Biospecimen Collection, Processing, and Storage: From the Consortium for the Study of Chronic Pancreatitis, Diabetes, and Pancreatic Cancer.

High-quality and well-annotated biorepositories are needed to better understand the pathophysiology and biologic mechanisms of chronic pancreatitis (CP) and its consequences. We report a methodology for the development of a robust standard operating procedure (SOP) for a biorepository based on the experience of the clinical centers within the consortium to study Chronic Pancreatitis, Diabetes and Pancreas Cancer Clinical Centers (CPDPC), supported by the National Cancer Institute and the National Institute for Diabetes and Digestive and Kidney Diseases as a unique multidisciplinary model to study CP, diabetes, and pancreatic cancer in both children and adults. Standard operating procedures from the CPDPC centers were evaluated and consolidated. The literature was reviewed for standard biorepository operating procedures that facilitated downstream molecular analysis. The existing literature on biobanking practices was harmonized with the SOPs from the clinical centers to produce a biorepository for pancreatic research. This article reports the methods and basic principles behind the creation of SOPs to develop a biorepository for the CPDPC. These will serve as a guide for investigators developing biorepositories in pancreas research. Rigorous and meticulous adherence to standardized biospecimen collection will facilitate investigations to better understand the pathophysiology and biologic mechanisms of CP, diabetes, and pancreatic cancer.

The mucinous domain of pancreatic carboxyl-ester lipase (CEL) contains core 1/core 2 O-glycans that can be modified by ABO blood group determinants.

Carboxyl-ester lipase (CEL) is a pancreatic fat-digesting enzyme associated with human disease. Rare mutations in the CEL gene cause a syndrome of pancreatic exocrine and endocrine dysfunction denoted MODY8, whereas a recombined CEL allele increases the risk for chronic pancreatitis. Moreover, CEL has been linked to pancreatic ductal adenocarcinoma (PDAC) through a postulated oncofetal CEL variant termed feto-acinar pancreatic protein (FAPP). The monoclonal antibody mAb16D10 was previously reported to detect a glycotope in the highly O-glycosylated, mucin-like C terminus of CEL/FAPP. We here assessed the expression of human CEL in malignant pancreatic lesions and cell lines. CEL was not detectably expressed in neoplastic cells, implying that FAPP is unlikely to be a glycoisoform of CEL in pancreatic cancer. Testing of the mAb16D10 antibody in glycan microarrays then demonstrated that it recognized structures containing terminal GalNAc-α1,3(Fuc-α1,2)Gal (blood group A antigen) and also repeated protein sequences containing GalNAc residues linked to Ser/Thr (Tn antigen), findings that were supported by immunostainings of human pancreatic tissue. To examine whether the CEL glycoprotein might be modified by blood group antigens, we used high-sensitivity MALDI-TOF MS to characterize the released O-glycan pool of CEL immunoprecipitated from human pancreatic juice. We found that the O-glycome of CEL consisted mainly of core 1/core 2 structures with a composition depending on the subject's FUT2 and ABO gene polymorphisms. Thus, among digestive enzymes secreted by the pancreas, CEL is a glycoprotein with some unique characteristics, supporting the view that it could serve additional biological functions to its cholesteryl esterase activity in the duodenum.

Early-Onset Acute Recurrent and Chronic Pancreatitis Is Associated with PRSS1 or CTRC Gene Mutations.

OBJECTIVES: To assess whether the age of onset was associated with unique features or disease course in pediatric acute recurrent pancreatitis (ARP) or chronic pancreatitis (CP). STUDY DESIGN: Demographic and clinical information on children with ARP or CP was collected at INSPPIRE (INternational Study Group of Pediatric Pancreatitis: In Search for a CuRE) centers. The Cochran-Armitage trend test and Jonckheere-Terpstra test were used to examine for differences between pediatric age groups (<6, 6-11, and ≥12 years). RESULTS: Between September 2012 and March 2016, 342 children with ARP or CP were enrolled; 129 (38%) were <6 years of age at the time of first diagnosis of acute pancreatitis, 111 (32%) were 6-11 years of age, and 102 (30%) were ≥12 years of age. Early-onset disease was associated with mutations in cationic trypsinogen (PRSS1) (P < .01), chymotrypsin C (CTRC) (P = .01), family history of acute pancreatitis (P = .02), family history of CP (P < .01), biliary cysts (P = .04), or chronic renal failure (P = .02). Later-onset disease was more commonly present with hypertriglyceridemia (P = .04), ulcerative colitis (P = .02), autoimmune diseases (P < .0001), or medication use (P < .01). Children with later-onset disease also were more likely to visit the emergency department (P < .05) or have diabetes (P < .01). CONCLUSIONS: Early-onset pancreatitis is associated strongly with PRSS1 or CTRC mutations and family history of pancreatitis. Children with later-onset disease are more likely to have nongenetic risk factors. Future studies are needed to investigate whether the disease course, response to therapy, or clinical outcomes differ relative to the timing of disease onset.

Risk Factors for Asparaginase-associated Pancreatitis: A Systematic Review.

GOALS: To evaluate potential risk factors for the development of asparaginase-associated pancreatitis (AAP), we performed a systematic review of the current literature from January 1946 through May 2015. BACKGROUND: Asparaginase, a primary treatment for the most common childhood cancer, acute lymphoblastic leukemia (ALL), is a well-described cause of pancreatitis. Further, pancreatitis is among the most burdensome and common complications of asparaginase treatment and represents a major reason for early-drug termination and inferior outcomes. The literature lacks clarity about the risk factors for AAP, and this knowledge gap has hampered the ability to reliably predict which patients are likely to develop AAP. STUDY: In an expansive screen, 1842 citations were funneled into a review of 59 full articles, of which 10 were deemed eligible based on predetermined inclusion criteria. RESULTS: Of the 10 identified studies, only 2 studies showed that children above 10 years of age had a >2-fold risk of AAP compared with younger children. Patients placed in high-risk ALL categories had a greater incidence of pancreatitis in 2 studies. In addition, use of pegylated asparaginase resulted in a higher incidence of AAP in 1 study. CONCLUSIONS: In this systematic review, older age, asparaginase formulation, higher ALL risk stratification, and higher asparaginase dosing appear to play a limited role in the development of AAP. Further studies are needed to probe the underlying mechanisms contributing to the development of pancreatitis in patients receiving asparaginase.

Chronic Pancreatitis in the 21st Century - Research Challenges and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop.

A workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to focus on research gaps and opportunities in chronic pancreatitis (CP) and its sequelae. This conference marked the 20th year anniversary of the discovery of the cationic trypsinogen (PRSS1) gene mutation for hereditary pancreatitis. The event was held on July 27, 2016, and structured into 4 sessions: (1) pathophysiology, (2) exocrine complications, (3) endocrine complications, and (4) pain. The current state of knowledge was reviewed; many knowledge gaps and research needs were identified that require further investigation. Common themes included the need to design better tools to diagnose CP and its sequelae early and reliably, identify predisposing risk factors for disease progression, develop standardized protocols to distinguish type 3c diabetes mellitus from other types of diabetes, and design effective therapeutic strategies through novel cell culture technologies, animal models mimicking human disease, and pain management tools. Gene therapy and cystic fibrosis conductance regulator potentiators as possible treatments of CP were discussed. Importantly, the need for CP end points and intermediate targets for future drug trials was emphasized.

Risk Factors Associated With Pediatric Acute Recurrent and Chronic Pancreatitis: Lessons From INSPPIRE.

IMPORTANCE: Pediatric acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) are poorly understood. OBJECTIVE: To characterize and identify risk factors associated with ARP and CP in childhood. DESIGN, SETTING, AND PARTICIPANTS: A multinational cross-sectional study of children with ARP or CP at the time of enrollment to the INSPPIRE (International Study Group of Pediatric Pancreatitis: In Search for a Cure) study at participant institutions of the INSPPIRE Consortium. From August 22, 2012, to February 8, 2015, 155 children with ARP and 146 with CP (aged ≤19 years) were enrolled. Their demographic and clinical information was entered into the REDCap (Research Electronic Data Capture) database at the 15 centers. Differences were analyzed using 2-sample t test or Wilcoxon rank sum test for continuous variables and Pearson χ2 test or Fisher exact test for categorical variables. Disease burden variables (pain variables, hospital/emergency department visits, missed school days) were compared using Wilcoxon rank sum test. MAIN OUTCOMES AND MEASURES: Demographic characteristics, risk factors, abdominal pain, and disease burden. RESULTS: A total of 301 children were enrolled (mean [SD] age, 11.9 [4.5] years; 172 [57%] female); 155 had ARP and 146 had CP. The majority of children with CP (123 of 146 [84%]) reported prior recurrent episodes of acute pancreatitis. Sex distribution was similar between the groups (57% female in both). Hispanic children were less likely to have CP than ARP (17% vs 28%, respectively; odds ratio [OR] = 0.51; 95% CI, 0.29-0.92; P = .02). At least 1 gene mutation in pancreatitis-related genes was found in 48% of patients with ARP vs 73% of patients with CP (P < .001). Children with PRSS1 or SPINK1 mutations were more likely to present with CP compared with ARP (PRSS1: OR = 4.20; 95% CI, 2.14-8.22; P < .001; and SPINK1: OR = 2.30; 95% CI, 1.03-5.13; P = .04). Obstructive risk factors did not differ between children with ARP or CP (33% in both the ARP and CP groups), but toxic/metabolic risk factors were more common in children with ARP (21% overall; 26% in the ARP group and 15% in the CP group; OR = 0.55; 95% CI, 0.31-0.99; P = .046). Pancreatitis-related abdominal pain was a major symptom in 81% of children with ARP or CP within the last year. The disease burden was greater in the CP group compared with the ARP group (more emergency department visits, hospitalizations, and medical, endoscopic, and surgical interventions). CONCLUSIONS AND RELEVANCE: Genetic mutations are common in both ARP and CP. Ethnicity and mutations in PRSS1 or SPINK1 may influence the development of CP. The high disease burden in pediatric CP underscores the importance of identifying predisposing factors for progression of ARP to CP in children.

Direct Costs of Acute Recurrent and Chronic Pancreatitis in Children in the INSPPIRE Registry.

OBJECTIVE: To estimate selected direct medical care costs of children with chronic pancreatitis (CP) and acute recurrent pancreatitis (ARP). METHODS: We performed a cross-sectional study of data from International Study Group of Pediatric Pancreatitis: In Search for a Cure (INSPPIRE), a multinational registry of children with ARP or CP. We determined health care utilization and estimated costs of hospitalizations, surgical and endoscopic procedures, and medications in our study population. Health care utilization data were obtained from all subjects enrolled in the study, and costs were calculated using national United States costs. RESULTS: We included 224 subjects (median age 12.7 years), 42% of whom had CP. Mean number of hospitalizations, including for surgery and endoscopic retrograde cholangiopancreatography, was 2.3 per person per year, costing an estimated average $38,755 per person per year. Including outpatient medications, estimated total mean cost was $40,589 per person per year. Subjects using surgical procedures or endoscopic retrograde cholangiopancreatography incurred mean annual costs of $42,951 per person and $12,035 per person, respectively. Estimated annual costs of pancreatic enzyme replacement therapy, diabetic medications, and pain medications were $4114, $1761, and $614 per person, respectively. In an exploratory analysis, patients with the following characteristics appear to accrue higher costs than those without them: more frequent ARP attacks per year, reported constant or episodic pain, family history of pancreatic cancer, and use of pain medication. CONCLUSIONS: ARP and CP are uncommon childhood conditions. The severe burden of disease associated with these conditions and their chronicity results in high health care utilization and costs. Interventions that reduce the need for hospitalization could lower costs for these children and their families.

Pediatric chronic pancreatitis is associated with genetic risk factors and substantial disease burden.

OBJECTIVE: To determine the clinical presentation, diagnostic variables, risk factors, and disease burden in children with chronic pancreatitis. STUDY DESIGN: We performed a cross-sectional study of data from the International Study Group of Pediatric Pancreatitis: In Search for a Cure, a registry of children with acute recurrent pancreatitis and chronic pancreatitis. Between-group differences were compared using Wilcoxon rank-sum test. RESULTS: Among 170 subjects in the registry, 76 (45%) had chronic pancreatitis; 57% were female, 80% were white; median age at diagnosis was 9.9 years. Pancreatitis-predisposing genetic mutations were identified in 51 (67%) and obstructive risk factors in 25 (33%). Toxic/metabolic and autoimmune factors were uncommon. Imaging demonstrated ductal abnormalities and pancreatic atrophy more commonly than calcifications. Fifty-nine (77%) reported abdominal pain within the past year; pain was reported as constant and receiving narcotics in 28%. Children with chronic pancreatitis reported a median of 3 emergency department visits and 2 hospitalizations in the last year. Forty-seven subjects (70%) missed 1 day of school in the past month as the result of chronic pancreatitis; 26 (34%) missed 3 or more days. Children reporting constant pain were more likely to miss school (P = .002), visit the emergency department (P = .01), and experience hospitalizations (P = .03) compared with children with episodic pain. Thirty-three children (43%) underwent therapeutic endoscopic retrograde pancreatography; one or more pancreatic surgeries were performed in 30 (39%). CONCLUSIONS: Chronic pancreatitis occurs at a young age with distinct clinical features. Genetic and obstructive risk factors are common, and disease burden is substantial.

A case of pancreatitis, panniculitis and polyarthritis syndrome: Elucidating the pathophysiologic mechanisms of a rare condition.

Pancreatitis-Panniculitis-Polyarthritis (PPP) syndrome is rare and its physiopathology unclear. A 6-year old boy suffered of traumatic pancreatitis complicated by PPP syndrome. Extensive investigations demonstrated high levels of pancreatic lipase and fatty acids in the affected peripheral tissues. These findings support the sequence of peripheral lipolysis and fatty acid accumulation inducing tissue inflammation.

The histopathology of PRSS1 hereditary pancreatitis.

Hereditary pancreatitis is an autosomal dominant disorder with 80% penetrance and variable expressivity. The vast majority of cases have been linked to mutations within the cationic trypsinogen gene, also referred to as serine protease 1 (PRSS1). Other than inheritance, PRSS1 pancreatitis has been considered clinically and pathologically indistinguishable from other etiologies of chronic pancreatitis. However, to date, the histologic findings of PRSS1 pancreatitis have not been well described. We, therefore, collected pancreatic specimens from 10 PRSS1 patients of various ages and examined their clinicopathologic features. Patients at the time of resection ranged in age from 9 to 66 years (median, 29 y), with a slight female predominance (60%). All patients reported a history of intermittent abdominal pain, with an age of onset ranging from infancy to 21 years of age. Examination of the gross and microscopic findings suggested a sequential pattern of changes with increasing patient age. In pediatric patients (n=4), although in most cases the pancreas was grossly normal, there was microscopic variation in lobular size and shape. Although the central portions of the pancreas displayed parenchymal loss accompanied by loose perilobular and interlobular fibrosis, the periphery was remarkable for replacement by mature adipose tissue. These changes were more developed in younger adults (n=2), in whom fatty replacement seemed to extend from the periphery to the central portions of the pancreas. With older patients (n=4), the pancreas showed marked atrophy and extensive replacement by mature adipose tissue with scattered islets of Langerhans and rare acinar epithelium concentrated near the main pancreatic duct. In summary, PRSS1 hereditary pancreatitis is characterized by progressive lipomatous atrophy of the pancreas.

Total pancreatectomy and islet autotransplantation in chronic pancreatitis: recommendations from PancreasFest.

DESCRIPTION: Total pancreatectomy with islet autotransplantation (TPIAT) is a surgical procedure used to treat severe complications of chronic pancreatitis or very high risk of pancreatic cancer while reducing the risk of severe diabetes mellitus. However, clear guidance on indications, contraindications, evaluation, timing, and follow-up are lacking. METHODS: A working group reviewed the medical, psychological, and surgical options and supporting literature related to TPIAT for a consensus meeting during PancreasFest. RESULTS: Five major areas requiring clinical evaluation and management were addressed: These included: 1) indications for TPIAT; 2) contraindications for TPIAT; 3) optimal timing of the procedure; 4) need for a multi-disciplinary team and the roles of the members; 5) life-long management issues following TPIAP including diabetes monitoring and nutrition evaluation. CONCLUSIONS: TPIAT is an effective method of managing the disabling complications of chronic pancreatitis and risk of pancreatic cancer in very high risk patients. Careful evaluation and long-term management of candidate patients by qualified multidisciplinary teams is required. Multiple recommendations for further research were also identified.

The Arg92Cys colipase polymorphism impairs function and secretion by increasing protein misfolding.

Colipase is essential for efficient fat digestion. An arginine-to-cysteine polymorphism at position 92 of colipase (Arg92Cys) associates with an increased risk for developing type-2 diabetes through an undefined mechanism. To test our hypothesis that the extra cysteine increases colipase misfolding, thereby altering its intracellular trafficking and function, we expressed Cys92 colipase in HEK293T cells. Less Cys92 colipase is secreted and more is retained intracellularly in an insoluble form compared with Arg92 colipase. Nonreducing gel electrophoresis suggests the folding of secreted Cys92 colipase differs from Arg92 colipase. Cys92 colipase misfolding does not trigger the unfolded protein response (UPR) or endoplasmic reticulum (ER) stress. The ability of secreted Cys92 colipase to stimulate pancreatic triglyceride lipase (PTL) is reduced with all substrates tested, particularly long-chain triglycerides. The reaction of Cys92 colipase with triolein and Intralipid has a much longer lag time, reflecting decreased ability to anchor PTL on those substrates. Our data predicts that humans with the Arg92Cys substitution will secrete less functional colipase into the duodenum and have less efficient fat digestion. Whether inefficient fat digestion or another property of colipase contributes to the risk for developing diabetes remains to be clarified.

Increasing incidence of acute pancreatitis at an American pediatric tertiary care center: is greater awareness among physicians responsible?

OBJECTIVES: Studies show an increased incidence of adult acute pancreatitis (AP) in recent decades. The aim was to review pediatric AP incidence. METHODS: Retrospective review of computerized databases at the Children's Hospital of Pittsburgh from 1993 to 2004. The International Classification of Diseases, Ninth Revision, code 5770 Acute Pancreatitis was used; results were tabulated by discharge year and month. The incidence of AP was compared with orders for amylase and lipase testings and with the catchment population. RESULTS: Over the study period, there were a total of 1021 discharge diagnoses of AP (731 first diagnoses). The diagnosis of AP increased from a low of 28 total cases (21 first diagnoses) in 1993 to a high of 141 total cases (109 first diagnoses) in 2004. The catchment population decreased from 882,000 to 826,500. The estimated incidences of first AP admission were 2.4 to 13.2 per 100,000 children (years 1993-2004; r = 0.8339). Linear regression analysis suggests that increased testing for amylase and lipase could account for 94% of the change in all AP admissions (P = 5.1 x 10). CONCLUSIONS: The increased incidence of AP at the Children's Hospital of Pittsburgh from 1993 to 2004 may have been primarily driven by increased testing for the disease.

Lipid-dependent cytotoxicity by the lipase PLRP2 and by PLRP2-positive cytotoxic T lymphocytes (CTLs).

IL-4 induces a lipase, pancreatic lipase related protein 2 (PLRP2), in cytotoxic T lymphocytes (CTLs). Because PLRP2 in semen can mediate lipid-dependent toxicity to sperm, we questioned whether CTL-derived PLRP2 could support similar cytotoxicity toward tumor cells. Recombinant PLRP2 was toxic to P815 tumor cells in 48 h when lipid and another protein, colipase, were present. However, PLRP2-positive CTLs (induced with many lots of IL-4) were unable to mediate lipid-dependent cytotoxicity. Notably, CTLs induced with only one lot of IL-4 had lipid-dependent cytotoxicity. The exceptional lot of IL-4 was effective in multiple experiments at inducing lipid-dependent cytotoxicity. The lipid-dependent cytotoxicity it induced was determined to be perforin-independent. CTLs induced with IL-4 that was unable to induce lipid-dependent cytotoxicity had mRNA for PLRP2 but not mRNA for colipase. Therefore, we added exogenous colipase to the CTL assays but still cytotoxicity was unchanged. We conclude (1) that lipid-dependent cytotoxicity, promoted by the lipase PLRP2 and colipase, will kill tumor cells and (2) that more than PLRP2 alone is required for lipid-dependent cytotoxicity mediated by CTLs.