PubMed Health⌕ Search

Biomedical subjects

A G Stansfield

Publications and source records attributed to A G Stansfield.

4 recordsLinked to original sources

Inhibition of T-cell mediated cytotoxicity by Novobiocin suggests multiple pathways for both CD4+ and CD8+ cytotoxic T cells.

The effect of the topoisomerase II inhibitor Novobiocin on T-cell mediated cytotoxicity was tested under various assay conditions. When effector cells were class I major histocompatibility complex (MHC)-specific CD8+ cytotoxic T cells (Tc), Novobiocin caused a biphasic pattern of inhibition and the two components of the inhibition could be separated based on Ca2+ requirement. Unseparated populations of class II MHC specific Tc, containing CD4+ and CD8+ effectors gave the same pattern of inhibition. When CD8+ cells were depleted from the latter population of effectors, different patterns of inhibition from those obtained with CD8+ Tc were seen and furthermore the target affected the pattern of inhibition. Overall the results add further support to there being more than one pathway of CD8+ T-cell mediated cytotoxicity and further illustrate differences between CD4+ and CD8+ T-cell mediated cytotoxicity.

Animals↗

Determination of protein size in chromatography column eluants by on-line photon correlation spectroscopy.

The dynamic light scattering technique of photon correlation spectroscopy has been used to determine biomacromolecule hydrodynamic radius in solutions flowing at rates similar to those experienced in liquid chromatographic separation systems. Such analyses can be performed rapidly (less than 5 s). The potential of the technique as an on-line noninvasive monitor for liquid chromatography is discussed.

Light↗

Terminal deoxynucleotidyl transferase activity in lymphoma.

Terminal deoxynucleotidyl transferase (TdT) was estimated in the tissues of 42 patients with lymphoma, whose cells were also typed by the use of surface markers. Four of the 8 patients with T-cell lymphoma were TdT+ including patients whose lymph nodes showed an undifferentiated or poorly differentiated appearance. The TdT- T-cell lymphomas included cases with diffuse histiocytic Sezary cell, diffuse, poorly differentiated and angio-immunoblastic histology. The tissues of 31 patients with B-cell lymphoma were invariably TdT-, whether the histology was poorly differentiated, well differentiated, nodular, diffuse, histiocytic or Burkitt type, and including cases with about equal proportions of T and B cells, and those whose cells showed non-capping and capping surface immunoglobulin. Hodgkin's tissue was also invariably TdT-. We conclude that estimation of TdT in tissues of patients with malignant lymphoma may be a useful test in diagnosing the T-cell lymphoma, particularly in patients with tumours of undifferentiated or poorly differentiated histology.

Adult↗