Immunohistochemical detection of CD3 in T-cell lymphomas: superior sensitivity of rabbit monoclonal 2GV6 antibody compared to mouse monoclonal F7·2·38 antibody.

Immunohistochemical detection of cluster of differentiation 3 (CD3) expression is important for the diagnosis of peripheral T-cell and NK-cell lymphomas. We compared CD3 staining intensity and percentage of CD3-positive cells in 28 T-cell lymphomas was compared using mouse anti-human CD3 antibody (clone F7·2·38) and rabbit anti-human CD3 antibody (clone 2GV6). Analysis was performed on tissue microarray sections containing 12 peripheral T-cell lymphomas unspecified, 4 angioimmunoblastic T-cell lymphomas, 6 adult T-cell leukemia/lymphomas, and 6 anaplastic large T-cell lymphomas. Compared to mouse antibody, CD3 staining intensity and the fraction of CD3-positive cells increased significantly with rabbit antibody in the vast majority of the T-cell lymphomas analyzed. The mean staining intensity of positive cells (weak: +1; moderate: +2; strong: +3) of all 28 lymphomas rose from 2·1 with mouse antibody to 2·5 with rabbit antibody. Notably, the mean fraction of strongly positive cells (+3) was 17·7% with mouse antibody and increased considerably to 49·1% with rabbit antibody. In addition, there was an overall 8% increase in CD3-positive cells if rabbit antibody was used. The results show that detection of CD3 expression in T-cell lymphomas with rabbit antibody represents an improved standard by increasing sensitivity and staining intensity. [ABSTRACT FROM AUTHOR]