Purification and immunodetection of the complete recombinant HER-2[neu] receptor produced in yeast.

For the first time, the full length recombinant HER-2[neu] receptor has been produced in a yeast (Arxula adeninivorans). It is one of the most studied membrane receptors in oncology and is involved in aggressive tumor formation. A yeast integration rDNA cassette containing the human gene coding for the HER-2[neu] protein was constructed and a screening procedure was performed to select the most productive transformant. Different detergents were tested for efficient solubilization of the membrane bound protein, with CHAPS giving the best results. To increase the yield of the recombinant protein from HER-2[neu] producing A. adeninivorans, optimal culture parameters were established for cultivation in bioreactor. The recombinant protein was subsequently assayed using ELISA and SPR immunoassays systems with antibodies raised against two different epitopes of the human receptor. In both cases, elution fractions containing the recombinant HER-2[neu] receptor successfully reacted with the immunoassays with limits of quantification below 100ngml(-1). These results demonstrate that the full length recombinant HER-2[neu] reported here has the potential to be a new standard for the detection of HER-2 type cancer.

Telecytological diagnosis of space-occupying lesions of the liver.

OBJECTIVE: In this study, the efficiency of telemedical consulting with regard to fine needle aspirates from space-occupying lesions (SOLs) of the liver is investigated for the first time. STUDY DESIGN: The study includes fine needle aspirations from 62 patients, 33 with hepatocellular carcinoma (HCC) and 29 with non-hepatic tumors. Using the Internet-based iPath system, the initial pathologist submitted 1-8 images from smears and cell block sections. One consultant assessed the cytological and another one the histological images. Both made their diagnoses independent of each other. A final diagnosis was made by immunochemistry of cell block sections. The cytological images were analyzed retrospectively for the occurrence of the most typical HCC indicators. The number of these indicators was related to the initial diagnoses of the three pathologists, and possible reasons for diagnostic errors were analyzed based on this analysis. RESULTS: The accuracy of the preliminary telemedical diagnoses regarding HCC was 82.0% for the cytological images and 87.7% for the histological images. Most of the false diagnoses occurred in tumors with unusual cytological and histological patterns. CONCLUSIONS: Telemedical consulting is a valuable tool to obtain a second opinion. However, for improvement of the diagnosis of HCC, supplementary immunochemical tests are necessary.

Making cytological diagnoses on digital images using the iPath network.

BACKGROUND: The iPath telemedicine platform Basel is mainly used for histological and cytological consultations, but also serves as a valuable learning tool. AIM: To study the level of accuracy in making diagnoses based on still images achieved by experienced cytopathologists, to identify limiting factors, and to provide a cytological image series as a learning set. METHOD: Images from 167 consecutive cytological specimens of different origin were uploaded on the iPath platform and evaluated by four cytopathologists. Only wet-fixed and well-stained specimens were used. The consultants made specific diagnoses and categorized each as benign, suspicious or malignant. RESULTS: For all consultants, specificity and sensitivity regarding categorized diagnoses were 83-92 and 85-93%, respectively; the overall accuracy was 88-90%. The interobserver agreement was substantial (κ = 0.791). The lowest rate of concordance was achieved in urine and bladder washings and in the identification of benign lesions. CONCLUSION: Using a digital image set for diagnostic purposes implies that even under optimal conditions the accuracy rate will not exceed to 80-90%, mainly because of lacking supportive immunocytochemical or molecular tests. This limitation does not disqualify digital images for teleconsulting or as a learning aid. The series of images used for the study are open to the public at http://pathorama.wordpress.com/extragenital-cytology-2013/.

Experience with telepathology in combination with diagnostic assistance systems in countries with restricted resources.

INTRODUCTION: We describe the use of telepathology in countries with restricted resources using two diagnosis assistance systems (Isabel and Memem7) in addition to the diagnoses made by experts in pathology via the iPath-Network. METHODS: A total of 156 cases, largely from Afghanistan, were analysed; 18 cases had to be excluded because of poor image quality. RESULTS: Of the remaining 138 cases (100%), a responsible physician provided a tentative diagnosis for 61.6% of them. With a diagnosis from a consultant pathologist, it was then possible to make a definite diagnosis in 84.8% of cases on the basis of images taken from hematoxylin and eosin staining sections alone. The use of the diagnosis assistance systems resulted in an ordered list of differential diagnoses in 82.6% (IsabelHealth) and in 74.6% (Memem7) of cases, respectively. Adding morphological terminology reduced the list of possible diagnoses to 52.2% (72 cases, Memem7), but improved their quality. DISCUSSION: In summary, diagnosis assistance systems are promising approaches to provide physicians in countries with restricted resources with lists of probable differential diagnoses, thus increasing the plausibility of the diagnosis of the consultant pathologist.