Autoantibodies in hospitalised patients with COVID-19.

Objectives: CD209L and its homologous protein CD209 act as alternative entry receptors for the SARS-CoV-2 virus and are highly expressed in the virally targeted tissues. We tested for the presence and clinical features of autoantibodies targeting these receptors and compared these with autoantibodies known to be associated with COVID-19.

Methods: Using banked samples ( = 118) from Johns Hopkins patients hospitalised with COVID-19, we defined autoantibodies against CD209 and CD209L by enzyme-linked immunosorbent assay (ELISA).

Anti-mitochondrial antibodies in systemic sclerosis target enteric neurons and are associated with GI dysmotility.

Background: Most patients with systemic sclerosis (SSc) experience gastrointestinal (GI) dysmotility. The enteric nervous system (ENS) regulates GI motility, and its dysfunction causes dysmotility. A subset of SSc patients harbor autoantibodies against the M2 mitochondrial antigen (AMA).

Anti-Sp4 and Anti-CCAR1 autoantibodies in UK vs. US patients with adult and juvenile-onset anti-TIF1Æ´-positive myositis.

Objectives: Anti-TIF1γ autoantibodies are associated with malignancy in adult-onset idiopathic inflammatory myopathy (IIM) and this risk is attenuated if patients are also positive for anti-specificity protein 4 (Sp4) or anti-cell division cycle apoptosis regulator protein 1 (CCAR1). In anti-TIF1γ positive US dermatomyositis (DM) patients, anti-Sp4 and anti-CCAR1 autoantibody frequencies are reported as 32% and 43% in adults and 9% and 19% in juveniles, respectively. This study aims to identify the frequency of anti-Sp4 and anti-CCAR1 in adult and juvenile UK anti-TIF1ƴ-positive myositis populations and report clinical associations.