摘要:

Considerable progress has been made in the development of methods for the localisation of antigens at the ultrastructural level using both transmission and scanning electron microscopy. There is currently no technique which is appropriate for all antigens, although, almost without exception, colloidal gold-linked reagents provide the electron-dense marker. For post-embedding techniques, several approaches are available all utilising low temperatures during the preparative stages. Cryosectioning and embedding by the PLT method both require the antigen to withstand some degree of fixation. For fixation-sensitive antigens, freeze substitution in solvents lacking fixative agents is an approach offering considerable potential.

ISSN:1010-4283    

DOI:10.1159/000217711

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The monoclonal antibody (MAb) 44–3A6 detects a 40-kD cell surface protein on adenocarcinomas and may serve as an effective marker for glandular differentiation. Immunohistochemical analysis of 123 paraffin-embedded malignant breast tissue specimens, 27 normal or benign breast disease specimens and 10 atypical hyperplasia specimens from patients without breast cancer was performed with MAb 44–3A6. The antigen was identified in 76% of breast cancer specimens, 0% of normal or benign breast disease specimens and 88% of the atypical hyperplasia specimens. MAb 44–3A6 also detected this antigen on adjacent normal breast ductal cells in 88% of the breast cancer specimens. There was no statistically significant correlation between immunoreactivity and histological mitotic or nuclear grade, recurrence or overall survival. This study suggests that the cell surface antigen detected by the MAb 44–3A6 may serve as an important marker in the differentiation of normal breast epithelium into an atypical or malignant

ISSN:1010-4283    

DOI:10.1159/000217712

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

In this prospective follow-up study the prognostic value of the tumor prostacyclin/thromboxane ratio in human breast carcinoma was investigated. The stable degradation products of prostacyclin and thromboxane (6-keto-PGF1α and TXB2, respectively), were measured by radio-immunoassay in homogenized primary tumours from 29 patients with primary non-metastatic breast cancer. The median follow-up was 43 months (range 24–58 months). Patients with recurrent disease or patients who died of breast cancer had a significantly higher 6-keto-PGF1α/TXB2 ratio than the disease-free survivors (p = 0.018 and p = 0.047, respectively). There was no significant difference in the 6-keto-PGF1α and TXB2 levels. These data indicate that the prostacyclin/thromboxane balance in the tumour might be a prognostic factor in breast cancer. Prostanoids may contribute to metastasis in breast cancer, but the problem is complex because the different prostaglandins have numerous actions that may produce both undesirable and desirable eff

ISSN:1010-4283    

DOI:10.1159/000217713

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A comparative analysis of radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques in determining placental protein 14 (PP14) levels in gynecologic patients was performed. Serum PPM levels were assessed in the patients in the last period of gestation, during menopause and in healthy nonpregnant controls. The possible discrepancy in PP14 levels was also examined in gynecologic patients with benign and malignant tumors. Both RIA and ELISA techniques proved to be sufficiently sensitive to measure PP14 concentration.

ISSN:1010-4283    

DOI:10.1159/000217714

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

CEA as well as normal cross-reacting antigens (NCA) are fixed to the cell membrane via phosphatidyUnositol (PI). To find out whether these antigens are internalized after antibody contact, acid pH desorption was compared to phospholipase C (PLC)-mediated cleavage of the antigen anchor. With the former procedure, marked differences in the desorb-ability of individual MAbs were noted, while PLC was able to cleave off surface-bound immune complexes irrespective of the MAb involved. From this it is concluded that internalization of MAb complexes of CEA/NCA, if occurring at all, is a low efficiency process.

ISSN:1010-4283    

DOI:10.1159/000217715

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

The molecular nature and possible presence of a glycan-phosphatidylinositol anchor (GPI-anchor) in CA125 molecules was investigated. Serial lectin affinity chromatography and N- or O-glycanase treatment to reduce antigenicity showed that CA125 contained certain N- and O-glycosylated sugar chains in the molecule, like a glycoprotein. CA125 released from ovarian cancer tissues increased time-dependently following phosphatidylino-sitol-specific phospholipase C (PI-PLC) treatment, concomitant with the release of tissue-unspecific alkaline phosphatase. Western blotting of CA125 treated by PI-PLC showed a single band of 90 kD instead of the 162- and 76-kD bands of the native antigen. Further, ovarian cancer tissues subjected to PI-PLC treatment lost the immunohistochemical localization of CA125 with OC125 antibody. Consequently, it is strongly suggested that CA125 is a glycoprotein that has both N- and O-linked sugar chains and a membranous GPI-anchoring moiety, and further, that its 90-kD form is the antigen without the GPI-anchor.

ISSN:1010-4283    

DOI:10.1159/000217716

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Catabolism of B6.2 and B72.3 monoclonal antibodies by human colon (LS174T) and lung (A549) tumor xenografts appears to be a variable and complex process. 125I-B72.3 and 125I-B6.2 bound to LS174T cells in vitro and localized in tumors in athymic mice. 125I-B6.2 bound to A549 cells in vitro, but did not localize in tumors. To understand these differences, tumors were grown around subcutaneously implanted micropore chambers and tumor fluid was analyzed for the presence of shed tumor antigen or functional antibody following intravenous injection. Up to two orders of magnitude lower functional B6.2 was detected in the A549 tumor fluid than in the LS174T tumor fluid. Also, A549 fluid almost totally (82–94%) inhibited binding of 125I-B6.2 to target cells in vitro due to free B6.2 antigen present in the chamber fluid. The micropore chambers utilized in this study have the potential for expanding our understanding of the way antibodies are metabolized in various types of tumors. Utility of an antibody in vivo cannot be entirely predicted from in vitro binding studies given that tumor related factors such as antibody transport, antibody catabolism and shed antigen may influence localization of antibodies in tumors. Monoclonal antibodies against nonshed antigens may prove to be more appropriate for cancer imaging and therap

ISSN:1010-4283    

DOI:10.1159/000217717

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

We have analyzed specific transcripts of the carcinoembryonic antigen (CEA) gene family expressed in 32 colorectal carcinomas (CRCs) and when possible, their corresponding adjacent ( 10 cm) mucosas. From 1 of the 32 patients, we obtained a corresponding tubulovillous adenoma. From 1 additional patient a Crohn’s disease sample was also evaluated. CEA mRNA was detectable by northern blot hybridization in 97% of the CRCs examined. Of these, 41 % expressed this transcript at higher levels in the tumor than in the corresponding distant mucosa. Nonspecific cross-reacting antigen (NCA) is another member of the CEA gene family. The NCA mRNA was detectable in 87% of the CRCs examined, with 92% of these expressing the NCA mRNA at higher levels than the corresponding distant mucosa. The NCA mRNA was not present at detectable levels in the tubulovillous adenoma and the specimen from Crohn’s colitis, whereas CEA was easily detected. Our findings demonstrate that NCA mRNA is more consistently overexpressed in colon carcinoma relative to distant mucosa than CEA m

ISSN:1010-4283    

DOI:10.1159/000217718

出版商:S. Karger AG    

年代:1991

数据来源: Karger