![HA-induced cluster formation is dependent on the expression of long-stretch CD44 variants. (A) Flow cytometric analysis of the expression of CD44 and its variants on MM cell lines. The means ± SD (bars) of 3 independent experiments are shown. (B) MM cells were cultured at 1 × 105 cells/mL in the presence of 120 ng/mL of HA under shear stress for 1 hour. Left panel: Representative phase-contrast images of MM cells. Bar represents 200 μm. Right panel: The means ± SD (bars) of the size of the cell clusters (n = 8-20). (C) KMM.1 sublines were cultured at 1 × 105 cells/mL with the indicated concentrations of HA under shear stress for 1 hour. Left panel: Representative phase-contrast images of 4 KMM.1 sublines cultured with 120 ng/mL of HA. Bar represents 400 μm. Right panel: The means ± SD (bars) of the size of cell clusters (n = 8-20). ∗P < .05 by one-way ANOVA with Tukey’s multiple comparison test. (D) Flow cytometric analysis of the expression of CD44 and its variants on primary MM cells isolated from the BM (except for EMD-MNC, which was isolated from the EMD lesion) of patients with (+) or without (−) EMD. In a patient with UPN5, BM samples were isolated at diagnosis [EMD (−)] and before the development of EMD [EMD (+)] (Supplemental Figure 2C). ∗P < .05 by one-way ANOVA with Tukey’s multiple comparison test between EMD (+) and EMD (−) groups.](https://ash.silverchair-cdn.com/ash/content_public/journal/bloodadvances/7/4/10.1182_bloodadvances.2022007291/7/blooda_adv-2022-007291-gr4.jpeg?Expires=1722779311&Signature=1Qd1bXBTK7ZXumfjG8y60uFnCifz~DccSxCrwkm6sjmVV156AzpO7jIOd93MQvy4osyOlN4ZkiXsn9o~nk1YkKblas4OFKFlON5Mw7KszXim6YMMjifINkgbn6j7vtHFoo3EuFZwNqMYoLpuFftj6-I-bP1nt5eTAydi7Lm81G5ns110oWOSYu~UYi46vzazcHLugLvRI5AJIut1Upb-Py8pou~sWxJruBZT9nOdhvw9M8DEhnd~JBnxNEykmKATz7OwwRUIT-g8W6p715EhlZ7EjuXldrqZVHP6uw7~WtgFM3SEoBRBN3ThSIoakccUeUBycrOSwfvzQiwYQvyfjw__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
HA-induced cluster formation is dependent on the expression of long-stretch CD44 variants. (A) Flow cytometric analysis of the expression of CD44 and its variants on MM cell lines. The means ± SD (bars) of 3 independent experiments are shown. (B) MM cells were cultured at 1 × 105 cells/mL in the presence of 120 ng/mL of HA under shear stress for 1 hour. Left panel: Representative phase-contrast images of MM cells. Bar represents 200 μm. Right panel: The means ± SD (bars) of the size of the cell clusters (n = 8-20). (C) KMM.1 sublines were cultured at 1 × 105 cells/mL with the indicated concentrations of HA under shear stress for 1 hour. Left panel: Representative phase-contrast images of 4 KMM.1 sublines cultured with 120 ng/mL of HA. Bar represents 400 μm. Right panel: The means ± SD (bars) of the size of cell clusters (n = 8-20). ∗P < .05 by one-way ANOVA with Tukey’s multiple comparison test. (D) Flow cytometric analysis of the expression of CD44 and its variants on primary MM cells isolated from the BM (except for EMD-MNC, which was isolated from the EMD lesion) of patients with (+) or without (−) EMD. In a patient with UPN5, BM samples were isolated at diagnosis [EMD (−)] and before the development of EMD [EMD (+)] (Supplemental Figure 2C). ∗P < .05 by one-way ANOVA with Tukey’s multiple comparison test between EMD (+) and EMD (−) groups.
