3D connectomes of reactive and neoplastic CD30 positive lymphoid cells and surrounding cell types

Area of Science:

• Oncology
• Immunology
• Cell Biology

Background:

• Classical Hodgkin lymphoma (cHL) diagnosis relies on identifying CD30-antigen positive Hodgkin- and Reed Sternberg (HRS) cells via light microscopy.
• CD30⁺ cells, both neoplastic (HRS) and reactive, exist within a microenvironment of lymphocytes and macrophages, crucial for cell survival.
• Understanding the cellular interactions within this microenvironment is key to elucidating cHL pathogenesis.

Purpose of the Study:

• To investigate the cellular interactions and 'connectomes' of CD30⁺ cells in cHL and reactive conditions using advanced 3D imaging.
• To compare the cellular microenvironments of different cHL subtypes (Mixed Cellularity and Nodular Sclerosis) and lymphadenitis.
• To evaluate the advantages of 3D imaging over traditional 2D methods for analyzing intercellular contacts.

Main Methods:

• Confocal laser scanning microscopy was employed to visualize contacts between CD30⁺ cells and specific immune cells (CD68⁺ macrophages, CD163⁺ macrophages, PD1⁺ lymphocytes, CD20⁺ B cells).
• Three-dimensional (3D) imaging techniques, including 3D reconstruction and printing, were used to create detailed visualizations of cellular networks.
• Quantitative analysis of cell volumes and the number of intercellular contacts was performed.

Main Results:

• Significant differences in the number of contacts between CD30⁺ cells and macrophages/B cells were observed between lymphadenitis and cHL subtypes.
• Mixed Cellularity cHL exhibited a higher number of contacts with CD163⁺ macrophages and fewer contacts with CD20⁺ B cells compared to lymphadenitis.
• Nodular Sclerosis cHL and Mixed Cellularity cHL differed primarily in their contacts with CD163⁺ macrophages, with MCcHL showing more connections.
• Reactive CD30⁺ cells had smaller volumes, correlating with fewer cellular contacts.

Conclusions:

• 3D imaging provides superior visualization of complex cellular networks and intercellular contacts compared to 2D methods.
• Distinct patterns of cellular interactions characterize different subtypes of cHL and reactive lymphoproliferative conditions.
• The 'connectome' of cHL, particularly the interactions with macrophages and B cells, varies significantly between subtypes, offering insights into disease biology.