Table I.

Number of cells in somite compartments of G8/complement-treated and control embryos

G8/complement	Dermatome	Dermomyotome	Myotome	Sclerotome
right	309 ± 115	192 ± 46	828 ± 370	228 ± 67
left	289 ± 110	178 ± 42	704 ± 221	271 ± 55
Buffer
right	169 ± 34	144 ± 22	246 ± 47	503 ± 61
left	144 ± 26	138 ± 9	246 ± 60	516 ± 107

Embryos were incubated with the G8 mAb and complement or Hanks' buffer at stage 2 and fixed 4.5 d after treatment. The number of nuclei in each compartment of the somite was determined by microscopy using the Image-Pro Plus image analysis software. Values are the mean ± the SD of 20 and 24 transverse sections through the wing levels of two treated and two control embryos, respectively. More cells were present in the dermatome, dermomyotome, and myotome-like regions of embryos treated with G8 and complement than embryos incubated with buffer alone (P ≤ 0.0005). The reverse was found for the sclerotome region of the somite (P ≤ 0.0005).