Tertiary lymphoid structures sustain cutaneous B cell activity in hidradenitis suppurativa.

Hidradenitis suppurativa (HS) is a chronic skin condition affecting approximately 1% of the US population. HS skin lesions are highly inflammatory and characterized by a large immune infiltrate. While B cells and plasma cells comprise a major component of this immune milieu, the biology and the contribution of these cells in HS pathogenesis are unclear. We aimed to investigate the dynamics and microenvironmental interactions of B cells within cutaneous HS lesions. Combining histological analysis, single-cell RNA sequencing, and spatial transcriptomics profiling of HS lesions, we defined the tissue microenvironment relative to B cell activity within this disease. Our findings identified tertiary lymphoid structures (TLSs) within HS lesions and described organized interactions among T cells, B cells, antigen-presenting cells, and skin stroma. We found evidence that B cells within HS TLSs actively underwent maturation, including participation in germinal center reactions and class switch recombination. Moreover, skin stroma and accumulating T cells were primed to support the formation of TLSs and facilitate B cell recruitment during HS. Our data definitively demonstrated the presence of TLSs in lesional HS skin and point to ongoing cutaneous B cell maturation through class switch recombination and affinity maturation during disease progression in this inflamed nonlymphoid tissue.

Tertiary Lymphoid Structures Sustain Cutaneous B cell Activity in Hidradenitis Suppurativa.

Background: Hidradenitis suppurativa (HS) skin lesions are highly inflammatory and characterized by a large immune infiltrate. While B cells and plasma cells comprise a major component of this immune milieu the biology and contribution of these cells in HS pathogenesis is unclear. Objective: We aimed to investigate the dynamics and microenvironmental interactions of B cells within cutaneous HS lesions. Methods: We combined histological analysis, single-cell RNA-sequencing (scRNAseq), and spatial transcriptomic profiling of HS lesions to define the tissue microenvironment relative to B cell activity within this disease. Results: Our findings identify tertiary lymphoid structures (TLS) within HS lesions and describe organized interactions between T cells, B cells, antigen presenting cells and skin stroma. We find evidence that B cells within HS TLS actively undergo maturation, including participation in germinal center reactions and class switch recombination. Moreover, skin stroma and accumulating T cells are primed to support the formation of TLS and facilitate B cell recruitment during HS. Conclusion: Our data definitively demonstrate the presence of TLS in lesional HS skin and point to ongoing cutaneous B cell maturation through class switch recombination and affinity maturation during disease progression in this inflamed non-lymphoid tissue.

Anti-myeloma activity and molecular logic operation by Natural Killer cells in microfluidic droplets.

Immune-targeted therapies that activate effector lymphocytes such as Natural Killer (NK) cells are currently being investigated for the treatment of Multiple myeloma (MM), the second most common form of hematological cancer. However, individual NK cells are highly heterogeneous in their cytolytic potential, making it difficult to detect, quantify and correlate the outcome of dynamic effector-target cell interactions at single cell resolution. Here, we present a microfluidic bioassay platform capable of activity-based screening of cellular and molecular immunotherapies. We identified distinct functional signatures associated with NK-MM cell interaction. The addition of immunomodulatory drug lenalidomide altered responses of NK-susceptible MM cells but not that of NK-tolerant MM cells. Antitumor cytotoxicity was significantly increased by the blockade of PD1/PDL1 axis as well as the clinically relevant cell line NK92, which were used to construct molecular logic functions (AND and NOT gates). A predictive agent-based mathematical model was developed to simulate progressive disease states and drug efficacy. The findings of the current study validate the applicability of this microfluidic cytotoxicity assay for immunotherapy screening, biocomputation and for future employment in detection of patient-specific cell response for precision medicine.

Competition of lattice and basis for alignment of nematic liquid crystals.

Due to elastic anisotropy, two-dimensional patterning of substrates can promote weak azimuthal alignment of adjacent nematic liquid crystals. Here we consider how such alignment can be achieved using a periodic square lattice of circular or elliptical motifs. In particular, we examine ways in which the lattice and motif can combine to favor differing orientations. Using Monte Carlo simulation and continuum elasticity we find, for circular motifs, that the coverage fraction controls both the polar anchoring angle and a transition in the azimuthal orientation. If the circles are generalized to ellipses, arbitrary control of the effective easy axis and effective anchoring potential becomes achievable by appropriate tuning of the ellipse motif relative to the periodic lattice patterning. This has possible applications in both monostable and bistable liquid crystal device contexts.