INTRODUCTION: Osteolytic bone destruction is a major clinical problem in multiple myeloma patients. Osteoclasts can differentiate in vitro from bone marrow-resident monocyte progenitors, such as common monocyte progenitors, as well as circulating monocytes. Various types of monocytes, including osteoclast precursors, appear to circulate systemically. METHODS: We investigated the possibility of demonstrating, by in vitro differentiation and flow cytometry, a circulating osteoclast precursor population in multiple myeloma (MM) patients by studying the distribution of CD14(+/++) CD11b(+) CD51/61(+) and CD14(+/++) CD16(+/-) populations. RESULTS: Under short-term in vitro osteoclastic differentiation conditions, almost all CD14 monocytes acquired CD51/61 and CD16 expression. Flow cytometry studies failed to demonstrate a statistically significant increase in circulating CD14(+/++) CD11b(+) CD51/61(+) populations in 20 MM patients with osteolytic lesions. However, the minor circulating CD14(+/++) CD16(+) fraction was significantly increased in MM patients compared with healthy volunteers (109.3 ± 63.1/mm(3) vs. 65.3 ± 34.9/mm(3) ; P = 0.005), but with no correlation with markers of tumour burden. The CD14(+/++) CD16(+) to CD14(+/++) CD16(-) ratio was higher in MM patients. CONCLUSION: The circulating CD14(+/++) CD11b(+) CD51/61(+) fraction was not correlated with bone lesions in MM patients. However, CD14(+/++) CD16(+) monocytes may be a candidate marker. A larger study must be conducted to confirm these promising results for the diagnosis and follow-up of MM patients.
INTRODUCTION: Osteolytic bone destruction is a major clinical problem in multiple myelomapatients. Osteoclasts can differentiate in vitro from bone marrow-resident monocyte progenitors, such as common monocyte progenitors, as well as circulating monocytes. Various types of monocytes, including osteoclast precursors, appear to circulate systemically. METHODS: We investigated the possibility of demonstrating, by in vitro differentiation and flow cytometry, a circulating osteoclast precursor population in multiple myeloma (MM) patients by studying the distribution of CD14(+/++) CD11b(+) CD51/61(+) and CD14(+/++) CD16(+/-) populations. RESULTS: Under short-term in vitro osteoclastic differentiation conditions, almost all CD14 monocytes acquired CD51/61 and CD16 expression. Flow cytometry studies failed to demonstrate a statistically significant increase in circulating CD14(+/++) CD11b(+) CD51/61(+) populations in 20 MMpatients with osteolytic lesions. However, the minor circulating CD14(+/++) CD16(+) fraction was significantly increased in MMpatients compared with healthy volunteers (109.3 ± 63.1/mm(3) vs. 65.3 ± 34.9/mm(3) ; P = 0.005), but with no correlation with markers of tumour burden. The CD14(+/++) CD16(+) to CD14(+/++) CD16(-) ratio was higher in MMpatients. CONCLUSION: The circulating CD14(+/++) CD11b(+) CD51/61(+) fraction was not correlated with bone lesions in MMpatients. However, CD14(+/++) CD16(+) monocytes may be a candidate marker. A larger study must be conducted to confirm these promising results for the diagnosis and follow-up of MMpatients.
Authors: Anaïs Marie Julie Møller; Jean-Marie Delaissé; Jacob Bastholm Olesen; Jonna Skov Madsen; Luisa Matos Canto; Troels Bechmann; Silvia Regina Rogatto; Kent Søe Journal: Bone Res Date: 2020-07-01 Impact factor: 13.567
Authors: Anaïs Marie Julie Møller; Jean-Marie Delaissé; Jacob Bastholm Olesen; Jonna Skov Madsen; Luisa Matos Canto; Troels Bechmann; Silvia Regina Rogatto; Kent Søe Journal: Bone Res Date: 2020-07-01 Impact factor: 13.567