GRAPPA 2023 Basic Science Workshop: What to Expect From Animal Models for Psoriatic Arthritis and Psoriasis.

Animal models help to drive research into psoriasis and psoriatic arthritis (PsA), particularly when studies in humans are not feasible. There are no animal models that perfectly mimic psoriatic disease (PsD) and so the pros and cons of each existing model must be considered for appropriate experimental design. Roughly, the existing animal models for PsD can be divided into 4 categories: (1) spontaneous models, (2) transgenic models, (3) inducible models, and (4) xenotransplantation models.

Impact of barrier tissue inflammation and physical activity on joint homeostasis in mice.

Objectives: To investigate whether physical activity interferes with joint homeostasis in the presence of distant inflammation originating at barrier tissues such as skin or gut.

Methods: Eight-week-old male C57/Bl6 mice were treated with imiquimod cream on a shaved area of the back skin or with dextran sodium sulphate dissolved in the drinking water to induce psoriasis-like skin or inflammatory bowel disease-like gut inflammation. Afterwards, one group of mice was subjected to a 4-week forced running routine (n = 10 per group).

Spondyloarthritis on the Move: Biomechanical Benefits or Harm.

Purpose Of Review: Physical activity is beneficial in several diseases including spondyloarthritis despite mechanical stress being suggested as a trigger of disease onset or activity. Moreover, there is no clear answer as to where physiological loading of the joints ends and pathological overloading begins. The aim of this review is to provide an overview of what is known about exercise and biomechanical loading in spondyloarthritis.

Behavior of metastatic breast cancer according to subtype.

Purpose: To explore the impact of breast cancer subtype on metastatic behavior and long-term outcome defined as breast cancer specific survival (BCSS).

Methods: Retrospective single centre cross-sectional study of 5972 patients with newly diagnosed, unilateral first diagnosis of breast cancer, diagnosed 2000-2010. Patients had either early breast cancer (EBC) treated primarily by surgery (SURG n = 5072), neoadjuvant systemic therapy (NEO n = 592), or upfront metastatic disease (META n = 308).

Bone Disease in Axial Spondyloarthritis.

Axial spondyloarthritis is a chronic inflammatory skeletal disorder with an important burden of disease, affecting the spine and sacroiliac joints and typically presenting in young adults. Ankylosing spondylitis, diagnosed by the presence of structural changes to the skeleton, is the prototype of this disease group. Bone disease in axial spondyloarthritis is a complex phenomenon with the coexistence of bone loss and new bone formation, both contributing to the morbidity of the disease, in addition to pain caused by inflammation.

Microtrauma: no longer to be ignored in spondyloarthritis?

Purpose Of Review: Novel clinical and animal model data support that biomechanical factors play a role in the onset and progression of spondyloarthritis. Bringing together these insights with the progress made in our understanding of the immunopathogenesis and genetic susceptibility of spondyloarthritis may provide new opportunities for better management.

Recent Findings: Tail suspension prevents arthritis in a tumor necrosis factor overexpression model.