Anti-CD66e polyclonal antibody

Carcinoembryonic antigen (CEA), also referred as CEACAM5, is integral to the adhesion process during cancer invasion and metastasis and is one of the most widely used tumor markers for assisting the diagnosis of cancer recurrence and cancer metastasis. Antibodies against CEA molecules have been developed for detection and diagnostic applications following tumor removal. Single domain antibodies (sdAbs) against CEA isolated from dromedary and llama exhibited high specificity in binding to tumor cells. However, because these CEA sdAbs were not designed to be orientated when conjugated to surface sensors, there is potential for significant improvements in their activity and limit of detection. Herein we modified the CEA sdAbs with two different C-terminal fusions designed to aid with orientation by way of the tail's charge and biotin binding. A fusion which incorporated the C-terminus addition of a positively charged tail (B5-GS3K) improved biosensor sensitivity to CEA while also retaining the sub-nanomolar binding affinity and thermal stability of the unmodified sdAb. Using our fabricated surfaces on bare gold chips and a multiplexed surface plasmon resonance imager (SPRi), we quantified the specific binding activities, defined as the percentage of bound epitopes to the total immobilized, of the sdAb fusions and anti-CEA mAb. Our results demonstrate that monovalent B5-GS3K exhibited significantly improved binding activity, approximately 3-fold higher than bivalent mAb.

Background: Peritoneal recurrence of pancreatic cancer is a frequent and lethal outcome after R0 resection. A method to predict peritoneal recurrence could be helpful in its prevention. Materials and methods: Peritoneal washings were prospectively obtained from 29 patients in whom R0 resection was performed. Cytological examination (CY) and real-time reverse transcription polymerase chain reaction (RT-PCR) of the peritoneal washing for the detection of cancer-related genes, CEACAM5, KRT7, KRAS, and MUC1, were performed. Clinicopathological characteristics and real-time RT-PCR results of the peritoneal washing were compared between patients whose pancreatic cancer recurred peritoneally (n = 7) and those patients who it did not recur (n = 22). Results: Only one CY-positive (CY+) case was detected, and that patient recurred. MUC1 mRNA expression was significantly higher in the recurrence group (P = 0.015). Cumulative incidence-function analysis demonstrated that peritoneal recurrence rate was significantly higher in MUC1-positive (MUC1(+)) patients (P = 0.044). MUC1+ patients had significantly decreased disease-free survival (P = 0.009) and disease-specific survival (P = 0.031). MUC1 protein was detected in the primary tumor in 18 of 29 patients. However, no significant difference was observed in the expression of MUC1 protein in peritoneal washings from the primary tumor (P = 0.579). Conclusions: High expression of MUC1 mRNA in peritoneal washings is a significant risk factor for peritoneal recurrence of pancreatic cancer after R0 resection along with poor disease-specific survival. RT-PCR of MUC1 mRNA in peritoneal washing may be useful for individualization of adjuvant chemotherapy. (C) 2017 Elsevier Inc. All rights reserved.