Biomedical subjects

J I Neves

Publications and source records attributed to J I Neves.

3 recordsLinked to original sources

PubMed2005

Antigen retrieval methods and estrogen receptor immunoexpression using 1D5 antibody: a comparative study.

Long-term formalin tissue fixation results in antigen masking, probably through aldehydic linkage between proteins and fixative molecules. Immunohistochemistry results depend on the type of the detection procedure and the type of antibody used for the reaction. Considering the difficulty in working with estrogen receptor (ER) antibodies and the lack of standardization of the antigen retrieval methods, we quantified the immunoexpression of ER using the 1D5 antibody and a standard streptavidin-biotin detection procedure retrieving with microwave oven, steamer, pressure cooker, and water bath in a set of SBR grade 2 invasive breast carcinomas. Pressure-cooking provided the best results. No significant differences were observed in using the other methods. Pressure-cooking should be recommended as the method of choice for standardization of the ER immunohistochemical reaction.

Antibodies, Monoclonal↗

PubMedDate not supplied

Immunocytochemical study of malignant lymphoma in serous effusions.

OBJECTIVE: To cytologically evaluate a large series of serous effusions associated with malignant lymphoma (ML), identify the immunoreaction patterns of the cells from selected positive cases and to investigate the correlation of cytomorphology with tissue section diagnosis. STUDY DESIGN: From 1966 to 1990, a review of the files of the Department of Anatomic Pathology, A. C. Camargo Hospital, disclosed 4,297 cases of serous effusions, 256 of which were associated with ML. Cytopathologically positive cases were selected for immunocytochemical study. All paraffin sections stained with hematoxylin and eosin were reviewed to confirm the malignancy of the cases. Immunostaining was performed on both cytocentrifuge slides previously stained with Papanicolaou stain and new sections of the biopsy samples using the immunoperoxidase method and avidin-biotin complex with monoclonal mouse antihuman B-cell marker L-26 and monoclonal (mouse) antihuman T-cell marker UCHL-1. RESULTS: Immunocytochemical reactions were performed in 54 cases: 22 were pan-B positive and 10 pan-T positive; 24 cases showed no reactivity for either monoclonal antibody. Immunohistochemical reactions were performed in 24 available cases: 15 were pan-B positive and pan-T positive; 3 cases showed no reactivity for either monoclonal antibody. Cytohistoimmunoreactions were similar in 11 pan-B positive cases and 2 pan-T positive cases. Three cases were negative for both markers, 4 cases were pan-T positive in tissue samples and negative in cytocentrifuge smears, 3 cases were pan-B positive in tissue and negative on cytology and 3 cases were negative for both markers in both tissue and cytologic specimens. CONCLUSION: Cytology is an effective method of evaluating serous effusions associated with malignant lymphoma: no false positive diagnosis was observed in this series. Immunophenotyping of lymphoid cells is useful to classify and confirm the cytologic diagnosis.

Animals↗

PubMedDate not supplied

Cytologic diagnosis of melanoma in serous effusions. A morphologic and immunocytochemical study.

The diversity of melanoma patterns greatly impairs the interpretation of malignant cells in effusion samples. The presence of melanin pigments greatly helps determine the histogenetic origin of the tumor, but unfortunately many cases do not exhibit this feature. We reviewed cases with a definitive diagnosis of melanoma in order to identify some useful characteristics of the morphologic examination of effusions. We also subjected the effusions to the HMB45 immunoreaction to determine the diagnostic usefulness of this monoclonal antibody. The study was performed on 21 effusion samples containing malignant cells, and the main cytologic findings were similar to those on other neoplasms except for the presence of melanin pigment. The HMB45 immunoreaction was very sensitive, confirming the diagnosis in 14 of 18 cases (77.8%). Melanin pigments seem to be useful markers for melanoma in effusions, and HMB45 can be used as an ancillary method in the differential diagnosis.

Adolescent↗