Figure 11.

STAGETOOL-derived antigen expression profiles for several proteins expressed in Sertoli cells and spermatogenic cells. Percentage (bar height) of predicted cells type (columns) of a given tubular stage (color) labeled by the corresponding antibody (row). SOX9 and SALL4 were uniformly expressed by Sertoli cells and spermatogonia, respectively. SCP3 staining was observed in all primary spermatocytes and a subset of spermatogonia, whereas CREM was seen only in round spermatids (RS). PNA localized to postmeiotic cells that have the acrosome, note well that acrosomes in early RS are absent (stage I) or very small in size (II-IV) (2). Androgen receptor (AR) was most highly expressed in early-to-mid stages, whereas upstream stimulatory factor 1 (USF1) was expressed stage-independently in Sertoli plus a subset of spermatogonia. STAGETOOL-derived expression profiles were as expected and biologically accurate. Background staining for some of the antigens (eg, Sertoli and early spermatocyte staining for SALL4) was primarily due to use of ovals to define cell boundaries. Occasionally areas from more than just one cell ended up in ovals causing a leakage of spermatogonial signal to neighboring early spermatocyte, for instance. Unspecific staining only slightly biased the analysis.