Development of an antibody fused with an antimicrobial peptide targeting Pseudomonas aeruginosa: A new approach to prevent and treat bacterial infections.

The increase in emerging drug resistant Gram-negative bacterial infections is a global concern. In addition, there is growing recognition that compromising the microbiota through the use of broad-spectrum antibiotics can impact long term patient outcomes. Therefore, there is the need to develop new bactericidal strategies to combat Gram-negative infections that would address these specific issues. In this study, we report and characterize one such approach, an antibody-drug conjugate (ADC) that combines (i) targeting the surface of a specific pathogenic organism through a monoclonal antibody with (ii) the high killing activity of an antimicrobial peptide. We focused on a major pathogenic Gram-negative bacterium associated with antibacterial resistance: Pseudomonas aeruginosa. To target this organism, we designed an ADC by fusing an antimicrobial peptide to the C-terminal end of the VH and/or VL-chain of a monoclonal antibody, VSX, that targets the core of P. aeruginosa lipopolysaccharide. This ADC demonstrates appropriately minimal levels of toxicity against mammalian cells, rapidly kills P. aeruginosa strains, and protects mice from P. aeruginosa lung infection when administered therapeutically. Furthermore, we found that the ADC was synergistic with several classes of antibiotics. This approach described in this study might result in a broadly useful strategy for targeting specific pathogenic microorganisms without further augmenting antibiotic resistance.

Approaching prosthesis infection environment: Development of an innovative in vitro Staphylococcus aureus biofilm model.

The major role and implication of bacterial biofilms in the case of bone and prosthesis infections have been highlighted and often linked to implant colonization. Management strategies of these difficult-to-treat infections consist in surgeries and antibiotic treatment, but the rate of relapse remains high, especially if Staphylococcus aureus, a high-virulent pathogen, is involved. Therapeutic approaches are not adapted to the specific features of biofilm in bone context whereas infectious environment is known to importantly influence biofilm structure. In the present study, we aim to characterize S. aureus SH1000 (methicillin-sensitive strain, MSSA) and USA300 (methicillin-resistant strain, MRSA) biofilm on different surfaces mimicking the periprosthetic environment. As expected, protein adsorption on titanium enhanced the number of adherent bacteria for both strains. On bone explant, USA300 adhered more than SH1000. The simultaneous presence of two different surfaces was also found to change the bacterial behaviour. Thus, proteins adsorption on titanium and bone samples (from bank or directly recovered after an arthroplasty) were found to be key parameters that influence S. aureus biofilm formation: adhesion, matrix production and biofilm-related gene regulation. These results highlighted the need for new biofilm models, more relevant with the infectious environment by using adapted culture medium and presence of surfaces that are representative of in situ conditions to better evaluate therapeutic strategies against biofilm.

Staphylococcus aureus Behavior on Artificial Surfaces Mimicking Bone Environment.

Infections, which interfere with bone regeneration, may be a critical issue to consider during the development of biomimetic material. Calcium phosphate (CaP) and type I collagen substrates, both suitable for bone-regeneration dedicated scaffolds, may favor bacterial adhesion. Staphylococcus aureus possesses adhesins that allow binding to CaP or collagen. After their adhesion, bacteria may develop structures highly tolerant to immune system attacks or antibiotic treatments: the biofilms. Thus, the choice of material used for scaffolds intended for bone sites is essential to provide devices with the ability to prevent bone and joint infections by limiting bacterial adhesion. In this study, we compared the adhesion of three different S. aureus strains (CIP 53.154, SH1000, and USA300) on collagen- and CaP-coating. Our objective was to evaluate the capacity of bacteria to adhere to these different bone-mimicking coated supports to better control the risk of infection. The three strains were able to adhere to CaP and collagen. The visible matrix components were more important on CaP- than on collagen-coating. However, this difference was not reflected in biofilm gene expression for which no change was observed between the two tested surfaces. Another objective was to evaluate these bone-mimicking coatings for the development of an in vitro model. Thus, CaP, collagen-coatings, and the titanium-mimicking prosthesis were simultaneously tested in the same bacterial culture. No significant differences were found compared to adhesion on surfaces independently tested. In conclusion, these coatings used as bone substitutes can easily be colonized by bacteria, especially CaP-coating, and must be used with an addition of antimicrobial molecules or strategies to avoid bacterial biofilm development.

Human Osteoblast-Conditioned Media Can Influence Staphylococcus aureus Biofilm Formation.

Osteoblasts are bone-forming and highly active cells participating in bone homeostasis. In the case of osteomyelitis and more specifically prosthetic joint infections (PJI) for which Staphylococcus aureus (S. aureus) is mainly involved, the interaction between osteoblasts and S. aureus results in impaired bone homeostasis. If, so far, most of the studies of osteoblasts and S. aureus interactions were focused on osteoblast response following direct interactions with co-culture and/or internalization models, less is known about the effect of osteoblast factors on S. aureus biofilm formation. In the present study, we investigated the effect of human osteoblast culture supernatant on methicillin sensitive S. aureus (MSSA) SH1000 and methicillin resistant S. aureus (MRSA) USA300. Firstly, Saos-2 cell line was incubated with either medium containing TNF-α to mimic the inflammatory periprosthetic environment or with regular medium. Biofilm biomass was slightly increased for both strains in the presence of culture supernatant collected from Saos-2 cells, stimulated or not with TNF-α. In such conditions, SH1000 was able to develop microcolonies, suggesting a rearrangement in biofilm organization. However, the biofilm matrix and regulation of genes dedicated to biofilm formation were not substantially changed. Secondly, culture supernatant obtained from primary osteoblast culture induced varied response from SH1000 strain depending on the different donors tested, whereas USA300 was only slightly affected. This suggested that the sensitivity to bone cell secretions is strain dependent. Our results have shown the impact of osteoblast secretions on bacteria and further identification of involved factors will help to manage PJI.

Comparison of Two Cutibacterium acnes Biofilm Models.

The study of biofilms in vitro is complex and often limited by technical problems due to simplified models. Here, we compared C. acnes biofilm formation, from species involved in bone and prosthesis infection, in a static model with a dynamic model. Using similar parameters, the percentage of live bacteria within the biofilm was higher in dynamic than in static approach. In both models, bacterial internalization in osteoblast-like cells, playing the role of stress factor, affected this proportion but in opposite ways: increase of live bacteria proportion in the static model (×2.04 ± 0.53) and of dead bacteria proportion (×3.5 ± 1.03) in the dynamic model. This work highlights the huge importance in the selection of a relevant biofilm model in accordance with the environmental or clinical context to effectively improve the understanding of biofilms and the development of better antibiofilm strategies.

Staphylococcus aureus Strain-Dependent Biofilm Formation in Bone-Like Environment.

Staphylococcus aureus species is an important threat for hospital healthcare because of frequent colonization of indwelling medical devices such as bone and joint prostheses through biofilm formations, leading to therapeutic failure. Furthermore, bacteria within biofilm are less sensitive to the host immune system responses and to potential antibiotic treatments. We suggested that the periprosthetic bone environment is stressful for bacteria, influencing biofilm development. To provide insights into S. aureus biofilm properties of three strains [including one methicillin-resistant S. aureus (MRSA)] under this specific environment, we assessed several parameters related to bone conditions and expected to affect biofilm characteristics. We reported that the three strains harbored different behaviors in response to the lack of oxygen, casamino acids and glucose starvation, and high concentration of magnesium. Each strain presented different biofilm biomass and live adherent cells proportion, or matrix production and composition. However, the three strains shared common responses in a bone-like environment: a similar production of extracellular DNA and engagement of the SOS response. This study is a step toward a better understanding of periprosthetic joint infections and highlights targets, which could be common among S. aureus strains and for future antibiofilm strategies.

Interaction of implant infection-related commensal bacteria with mesenchymal stem cells: a comparison between Cutibacterium acnes and Staphylococcus aureus.

Staphylococcus aureus and Cutibacterium acnes are involved in several tissue infections and can encounter mesenchymal stem cells (MSCs) during their role in tissue regenerative process. C. acnes and S. aureus internalization by three types of MSCs derived from bone marrow, dental pulp and Wharton's jelly; and bacterial biofilm production were compared. Internalization rates ranged between 1.7-6.3% and 0.8-2.7% for C. acnes and S. aureus, respectively. While C. acnes strains exhibited limited cytotoxic effect on MSCs, S. aureus were more virulent with marked effect starting after only 3 h of interaction. Both bacteria were able to produce biofilms with respectively aggregated and monolayered structures for C. acnes and S. aureus. The increase in C. acnes capacity to develop biofilm following MSCs' internalization was not linked to the significant increase in number of live bacteria, except for bone marrow-MSCs/C. acnes CIP 53.117 with 79% live bacteria compared to the 36% before internalization. On the other hand, internalization of S. aureus had no impact on its ability to form biofilms composed mainly of living bacteria. The present study underlined the complexity of MSCs-bacteria cross-interaction and brought insights into understanding the MSCs behavior in response to bacterial infection in tissue regeneration context.

Cutibacterium acnes Biofilm Study during Bone Cells Interaction.

Cutibacterium acnes is an opportunistic pathogen involved in Bone and Prosthesis Infections (BPIs). In this study, we observed the behavior of commensal and BPI C. acnes strains in the bone environment through bacterial internalization by osteoblast-like cells and biofilm formation. For the commensal strains, less than 1% of the bacteria were internalized; among them, about 32.7 ± 3.9% persisted intracellularly for up to 48 h. C. acnes infection seems to have no cytotoxic effect on bone cells as detected by LDH assay. Interestingly, commensal C. acnes showed a significant increase in biofilm formation after osteoblast-like internalization for 50% of the strains (2.8-fold increase). This phenomenon is exacerbated on a titanium support, a material used for medical devices. For the BPI clinical strains, we did not notice any increase in biofilm formation after internalization despite a similar internalization rate by the osteoblast-like cells. Furthermore, fluorescent staining revealed more live bacteria within the biofilm after osteoblast-like cell interaction, for all strains (BPIs and commensal). The genomic study did not reveal any link between their clinical origin and phylotype. In conclusion, we have shown for the first time the possible influence of internalization by osteoblast-like cells on commensal C. acnes.

Biopolymers-calcium phosphate antibacterial coating reduces the pathogenicity of internalized bacteria by mesenchymal stromal cells.

A multifunctional material system that kills bacteria and drives bone healing is urgently sought to improve bone prosthesis. Herein, the osteoinductive coating made of calcium phosphate/chitosan/hyaluronic acid, named Hybrid, was proposed as an antibacterial substrate for stromal cell adhesion. This Hybrid coating possesses a contact-killing effect reducing by 90% the viability of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) strains after 48 h of contact. In addition to the production of immunomodulatory mediators, Wharton's jelly (WJ-SCs), dental pulp (DPSCs) and bone marrow (BM-MSCs) derived stromal cells were able to release antibacterial and antibiofilm agents effective against S. aureus and P. aeruginosa strains, respectively. Studying the effect of the Hybrid coating on the internalization of S. aureus by the stromal cells, in acute-mimicking bone infection, highlighted an increase in the bacteria internalization by DPSCs and BM-MSCs when cultured on the Hybrid coating versus uncoated glass. Despite the internalization, Hybrid coating showed a beneficial effect by reducing the pathogenicity of the internalized bacteria. The formation of biofilm was reduced by at least 50% in comparison to internalized bacteria by stromal cells on uncoated glass. This work opens the route for the development of innovative antibacterial coatings by taking into account the internalization of bacteria by stromal cells.

Bone Environment Influences Irreversible Adhesion of a Methicillin-Susceptible Staphylococcus aureus Strain.

Prosthesis and joint infections are an important threat in public health, especially due to the development of bacterial biofilms and their high resistance to antimicrobials. Biofilm-associated infections increase mortality and morbidity rates as well as hospitalization costs. Prevention is the best strategy for this serious issue, so there is an urgent need to understand the signals that could induce irreversible bacterial adhesion on a prosthesis. In this context, we investigated the influence of the bone environment on surface adhesion by a methicillin-susceptible Staphylococcus aureus strain. Using static and dynamic biofilm models, we tested various bone environment factors and showed that the presence of Mg2+, lack of oxygen, and starvation each increased bacterial adhesion. It was observed that human osteoblast-like cell culture supernatants, which contain secreted components that would be found in the bone environment, increased bacterial adhesion capacity by 2-fold (p = 0.015) compared to the medium control. Moreover, supernatants from osteoblast-like cells stimulated with TNF-α to mimic inflammatory conditions increased bacterial adhesion by almost 5-fold (p = 0.003) without impacting on the overall biomass. Interestingly, the effect of osteoblast-like cell supernatants on bacterial adhesion could be counteracted by the activity of synthetic antibiofilm peptides. Overall, the results of this study demonstrate that factors within the bone environment and products of osteoblast-like cells directly influence S. aureus adhesion and could contribute to biofilm initiation on bone and/or prosthetics implants.

Perioperative Care of the Breastfeeding Patient.

Nurses providing surgical care in nonobstetrical ambulatory surgery centers or specialty hospitals without traditional lactation resources may need to care for patients who are breastfeeding. Nurses in these settings play an important role in supporting and protecting the breastfeeding relationship for nursing mothers separated from their infants during illness or surgical procedures. It is important for care providers to understand how hospitalization and the medications administered before, during, and after a surgical procedure affect mothers who are breastfeeding their infants. This article examines the effects of hospitalization on breastfeeding and focuses on preoperative and postoperative care considerations, including medication use, radiology imaging, interrupting and resuming breastfeeding, breast assessment, and milk storage.

Implementation and Organization of a Perioperative Lactation Program: A Descriptive Study.

INTRODUCTION: As breastfeeding rates rise, perioperative care of lactating women is an increasingly important issue. There is a lack of reports describing the implementation of perioperative lactation programs. Beginning in 2014, Memorial Sloan Kettering Cancer Center developed a perioperative lactation program to address the comprehensive care of lactating patients. The aim of this study was to determine the incidence of lactation in our perioperative population, as well as to describe preliminary data and experiences during the implementation of our program. MATERIALS AND METHODS: This retrospective descriptive study included lactating patients who underwent procedures requiring anesthesia care at our institution from August 2014 to February 2017. This period coincided with implementation of the lactation program, which focused on patient identification, education, and support, as well as staff education and collaboration. Patient volume and characteristics, procedure types, and intraoperative non-narcotic analgesic use were analyzed. RESULTS: Over the 30-month study period, we identified 80 lactating perioperative patients, with ∼2-3 patients presenting monthly. The median (range) age of the child was 5 (0.6-24) months. Most of our lactating patients were American Society of Anesthesiologists class I-II patients (81%), who underwent general anesthesia (89%), and received at least one non-narcotic analgesic intraoperatively (89%). CONCLUSION: Our study showed that we cared for lactating patients undergoing a wide range of procedures on a regular basis. The results from this study are intended to inform the next phase of our research, which will focus on determining how this work impacts outcomes such as postoperative lactation complications, breastfeeding resumption, and overall patient satisfaction.

A multicenter, retrospective medical record review of X-linked myotubular myopathy: The recensus study.

INTRODUCTION: X-linked myotubular myopathy (XLMTM), characterized by severe hypotonia, weakness, respiratory distress, and early mortality, is rare and natural history studies are few. METHODS: RECENSUS is a multicenter chart review of male XLMTM patients characterizing disease burden and unmet medical needs. Data were collected between September 2014 and June 2016. RESULTS: Analysis included 112 patients at six clinical sites. Most recent patient age recorded was ≤18 months for 40 patients and >18 months for 72 patients. Mean (SD) age at diagnosis was 3.7 (3.7) months and 54.3 (77.1) months, respectively. Mortality was 44% (64% ≤18 months; 32% >18 months). Premature delivery occurred in 34/110 (31%) births. Nearly all patients (90%) required respiratory support at birth. In the first year of life, patients underwent an average of 3.7 surgeries and spent 35% of the year in the hospital. DISCUSSION: XLMTM is associated with high mortality, disease burden, and healthcare utilization. Muscle Nerve 57: 550-560, 2018.

Prognostic Role of Serum Chloride Levels in Acute Decompensated Heart Failure.

BACKGROUND: Acute decompensated heart failure (ADHF) can be complicated by electrolyte abnormalities, but the major focus has been concentrated on the clinical significance of serum sodium levels. OBJECTIVES: This study sought to determine the prognostic significance of serum chloride levels in relation to serum sodium levels in patients with ADHF. METHODS: We reviewed 1,318 consecutive patients with chronic heart failure admitted for ADHF to the Cleveland Clinic between July 2008 and December 2013. We also validated our findings in an independent ADHF cohort from the University of Pennsylvania (n = 876). RESULTS: Admission serum chloride levels during hospitalization for ADHF were independently and inversely associated with long-term mortality (hazard ratio [HR] per unit change: 0.94; 95% confidence interval [CI]: 0.92 to 0.95; p < 0.001). After multivariable risk adjustment, admission chloride levels remained independently associated with mortality (HR per unit change: 0.93; 95% CI: 0.90 to 0.97; p < 0.001) in contrast to admission sodium levels, which were no longer significant (p > 0.05). Results were similar in the validation cohort in unadjusted (HR per unit change for mortality risk within 1 year: 0.93; 95% CI: 0.91 to 0.95; p < 0.001) and multivariable risk-adjusted analysis (HR per unit change for mortality risk within 1 year: 0.95; 95% CI: 0.92 to 0.99; p = 0.01). CONCLUSIONS: These observations in a contemporary advanced ADHF cohort suggest that serum chloride levels at admission are independently and inversely associated with mortality. The prognostic value of serum sodium in ADHF was diminished compared with chloride.

Including additional controls from public databases improves the power of a genome-wide association study.

Though genome-wide association studies (GWAS) have identified numerous susceptibility loci for common diseases, their use is limited due to the expense of genotyping large cohorts of individuals. One potential solution is to use 'additional controls', or genotype data from control individuals deposited in public repositories. While this approach has been used by several groups, the genetically heterogeneous nature of the population of the United States makes this approach potentially problematic. We empirically investigated the utility of this approach in a US-based GWAS. In a small GWAS of pancreatic cancer in New York, we observed clear population structure differences relative to controls from the database of Genotypes and Phenotypes (dbGaP). When we conduct the GWAS using these additional controls, we find large inflation of the test statistic that is properly corrected by using eigenvectors from principal components analysis as covariates. To deal with errors introduced due to different sources, we propose simultaneously genotyping a small number of controls along with cases and then comparing this group to the additional controls. We show that removing SNPs that show differences between these control groups reduces false-positive findings. Thus, through an empirical approach, this report provides practical guidance for using additional controls from publicly available datasets.

Studying cancer in minorities: a look at the numbers.

BACKGROUND: Inclusion of minorities is an important but challenging aspect of epidemiologic studies in the United States. One aspect of this challenge that has received little attention is the actual number of minorities with specific cancers. The authors aimed to understand how population characteristics affect the numbers of minority cancer cases in Surveillance, Epidemiology, and End Results (SEER) regions. METHODS: By using SEER data, the authors identified 6 cancers with higher incidence rates in racial and ethnic minorities and reviewed the annual number of cases of those cancers in SEER areas where there are large numbers of blacks, Hispanics, and Asians. The authors examined the age characteristics of the populations in SEER areas using data from the US Census. RESULTS: Although there are substantial numbers of cases for the most common cancers with higher incidence in blacks, their numbers are quite small for other cancers, <150 cases, and in many areas, <100 per year. Few registries have substantial numbers of Hispanics or Asians. As expected, the proportion of minority populations is lower in older age groups, whereas the proportion of non-Hispanic whites is larger. CONCLUSIONS: Because of the sharp decline in minority populations associated with age and the high age-specific incidence rates of most cancers, the actual number of minority cases is quite small for several cancers. Thus, the inclusion of minority groups in studies of any but the most common cancers presents a challenge.

Feasibility and yield of screening in relatives from familial pancreatic cancer families.

OBJECTIVES: Pancreatic adenocarcinoma is a lethal disease. Over 80% of patients are found to have metastatic disease at the time of diagnosis. Strategies to improve disease-specific outcome include identification and early detection of precursor lesions or early cancers in high-risk groups. In this study, we investigate whether screening at-risk relatives of familial pancreatic cancer (FPC) patients is safe and has significant yield. METHODS: We enrolled 309 asymptomatic at-risk relatives into our Familial Pancreatic Tumor Registry (FPTR) and offered them screening with magnetic resonance cholangiopancreaticogram (MRCP) followed by endoscopic ultrasound (EUS) with fine needle aspiration if indicated. Relatives with findings were referred for surgical evaluation. RESULTS: As of 1 August 2009, 109 relatives had completed at least one cycle of screening. Abnormal radiographic findings were present on initial screening in 18/109 patients (16.5%), 15 of whom underwent EUS. A significant abnormality was confirmed in 9 of 15 patients, 6 of whom ultimately had surgery for an overall diagnostic yield of 8.3% (9/109). Yield was greatest in relatives >65 years old (35%, 6/17) when compared with relatives 55-65 years (3%, 1/31) and relatives <55 years (3%, 2/61). CONCLUSIONS: Screening at-risk relatives from FPC families has a significant diagnostic yield, particularly in relatives >65 years of age, confirming prior studies. MRCP as initial screening modality is safe and effective.

Germline PALB2 mutation analysis in breast-pancreas cancer families.

BACKGROUND: Germline mutations in the PALB2 gene have been implicated in both breast cancer and pancreatic cancer susceptibility. The extent to which PALB2 mutations account for cancer susceptibility in breast-pancreas cancer families is unknown. METHODS: High Resolution Melting analysis and Multiplex Ligation-dependent Probe Amplification were performed to investigate the prevalence of PALB2 mutations in patients with either a personal history of both breast and pancreatic cancer or a personal history of breast cancer and a family history of a first degree relative with pancreatic cancer. RESULTS: No PALB2 mutations were identified in 77 breast-pancreas cancer families, which included 22 probands with a personal history of both breast and pancreatic cancer. CONCLUSION: Mutations within the PALB2 gene are rare events that do not account for a substantial proportion of cancer susceptibility in breast-pancreas cancer families. Routine screening of breast-pancreas cancer families for the presence of PALB2 mutations appears to be low yield.

Allergies, obesity, other risk factors and survival from pancreatic cancer.

Survival from pancreatic adenocarcinoma remains extremely poor, approximately 5% at 5 years. Risk factors include smoking, high body mass index (BMI), family history of pancreatic cancer, and long-standing diabetes; in contrast, allergies are associated with reduced risk. Little is known about associations between these factors and survival. We analyzed overall survival in relation to risk factors for 475 incident cases who took part in a hospital based case-control study. Analyses were conducted separately for those who did (160) and did not (315) undergo tumor resection. Kaplan-Meier methods were used to describe survival according to smoking, BMI, family history, diabetes, and presence of allergies. Cox proportional hazards models were used to adjust for covariates. There was no association with survival based on smoking, family history, or history of diabetes in either group. Among patients with resection, those with allergies showed nonstatistically significant longer survival, a median of 33.1 months (95% CI: 19.0-52.5) vs. 21.8 months (95% CI: 18.0-33.1), p = 0.25. The adjusted hazard ratio (HR) was 0.72 (95% CI: 0.43-1.23), p = 0.23. Among patients without resection, those with self-reported allergies survived significantly longer than those without allergies: 13.3 months (95% CI: 10.6-16.9) compared to 10.4 months (95% CI: 8.8-11.0), p = 0.04, with an adjusted HR of 0.68 (95% CI: 0.49-0.95), p = 0.02. Obesity was nonsignificantly associated with poorer survival, particularly in the resected group (HR = 1.62, 95% CI: 0.76-3.44). The mechanisms underlying the association between history of allergies and improved survival are unknown. These novel results need to be confirmed in other studies.

Allergies, variants in IL-4 and IL-4R alpha genes, and risk of pancreatic cancer.

BACKGROUND: Several studies in epidemiology indicate that risk of pancreatic cancer is reduced in individuals with allergies. Although genes have been identified that are critical in allergic response, polymorphisms in these genes have not been studied in relation to risk of pancreatic cancer. We hypothesized that variants in these genes are related to risk. METHODS: We investigated the association of allergies and pancreatic cancer in a hospital-based case-control study with 405 cases and 212 controls. In a subgroup of 149 cases and 135 controls, we studied the association of variants in IL-4 (C-589T, G3017T) and IL-4R alpha (Gln576Arg) with allergies and with risk of pancreatic cancer. RESULTS: We found reduced risk of pancreatic cancer associated with allergies, with adjusted odds ratios of 0.58 (95% CI 0.40-0.84) for any allergies, 0.45 (95% CI 0.29-0.70) for hay fever, and 0.43 (95% CI 0.23-0.80) for animals. The minor allele at each locus studied was associated with reduced risk of allergies in controls, leading us to hypothesize that they would be associated with increased risk of pancreatic cancer. Overall, there was no association between the genotypes studied and risk of pancreatic cancer. In analyses within strata defined by presence or absence of allergies, there were differences in risk associated with genotype for IL-4 G3017T: there was slightly increased risk among those with allergies and reduced risk among those without allergies. CONCLUSIONS: The consistent association of allergies with risk of pancreatic cancer and these results suggest that associations between variants in genes related to allergic response and pancreatic cancer warrant further study.