Calculate the mean for each cluster (C1, C2, C3, C4, C5), then rank them as S1, S2, S3, S4, S5
Compare S1 with S2 (z test)
if significant, assign S1 (C3) to Astrocytes
if not, merge S1 with S2, compare with S3
if significant, assign S1 and S2 to Astrocytes
if not, give up
Go back to 1 for a different marker to generate an assignment table
Asctrocyte: C3, C3/C4, C4 --> C3/C4