Laboratory measurement of autoantibodies to Annexin A1: Review and measurements in health and COVID-19.

Annexin A1, a protein released by neutrophils, is a potent regulator of inflammation in the intact form, but loses this activity when cleaved. The presence of autoantibodies to this protein can impact its function. An immunoassay, developed to measure autoantibodies to Annexin A1 in plasma or serum, has been developed and performances are reported.

Anti-Thrombin IgA in a Patient with Multiple Myeloma Leading to In Vitro Interference in Multiple Coagulation Tests and Confounding Diagnosis.

Background:  We report the case of a 59-year-old multiple myeloma patient in whom an anti-human thrombin IgA antibody led to prolonged in vitro coagulation times, suggesting inhibitors to all intrinsic coagulation factors in the absence of spontaneous bleeding.

Methods:  Routine and extensive special coagulation tests, in vivo bleeding time, and specific antibody testing were performed.

Results:  Although the patient did not suffer from spontaneous bleeding and had a normal in vivo bleeding time, the anti-human thrombin IgA autoantibody affected all coagulation assays involving human thrombin in vitro, mimicking inhibitors to intrinsic coagulation factors.

Autoimmune complications of COVID-19 and potential consequences for long-lasting disease syndromes.

The latest WHO report determined the increasing diversity within the CoV-2 omicron and its descendent lineages. Some heavily mutated offshoots of BA.5 and BA.

Annexin A1 Is Associated with Adverse Clinical Outcomes in Patients with COVID-19.

Severe coronavirus disease 2019 (COVID-19) is characterized by hyperinflammation, vascular damage, and hypercoagulability. Insufficient responses of Annexin A1 (AnxA1), a pro-resolving inhibitor of neutrophil infiltration and activation, might contribute to a severe course of the disease. We longitudinally evaluated AnxA1's role in terms of inflammation, vascular damage, and clinical outcomes in a large prospective cohort of patients with COVID-19.