BACKGROUND Immunoglobulin replacement therapy is an effective route of management for both infections and non-infectious complications in predominantly antibody deficiency (PAD). Trace levels of IgA (ranged from 0.4 to 2500 mg/ml), which exist in all immunoglobulin products, could lead to an increased susceptibility for adverse reactions in PAD patients. Furthermore, the exact mechanism which s...

BACKGROUND The aim of this study was to retrospectively examine how positive IgA-endomysial antibody (EMA) test results for celiac disease were being interpreted and acted on by physicians in the Calgary Health Region. METHODS We reviewed consecutive EMA test results, with or without a serum IgA, obtained during a 17-month period. Seropositive tests were cross-referenced to the surgical datab...

OBJECTIVE Systemic lupus erythematosus (SLE) is a severe autoimmune disease with rare remission and recurrent flare. Epstein-Barr virus (EBV) infection has been reported to be strongly associated with SLE in the United States, but with an inconclusive role in Asia. We investigated the role of EBV infection in patients with SLE in Taiwan, with one of the highest population densities in Asia. M...

Antibodies of human IgA isotype are critical components of the mucosal immune system, but little is known about their immunotherapeutic potential. Compared with IgG antibodies, IgA molecules carry a C-terminal tail piece extension of 18 amino acids with a free cysteine at position 471. This cysteine is required for the formation of dimeric IgA antibodies, but may impair molecular characteristic...

IgA is the most prevalent antibody type on mucosal surfaces and the second most prevalent antibody in circulation, yet its role in immune defense is not fully understood. Here we show that IgA is carried inside cells during virus infection, where it activates intracellular virus neutralization and innate immune signaling. Cytosolic IgA-virion complexes colocalize with the high-affinity antibody...

The accumulation of immunoglobulin (Ig)A antibody-secreting cells (ASCs) in the lactating mammary gland leads to secretion of antibodies into milk and their passive transfer to the suckling newborn. This transfer of IgA from mother to infant provides transient immune protection against a variety of gastrointestinal pathogens. Here we show that the mucosal epithelial chemokine CCL28 is up-regula...

Anti-Epstein-Barr virus (EBV) antibodies were tested in 11 children with chronic active EBV infection. Anti-virus capsid antigen (VCA)-IgG antibody titers ranged from 1:640 to 1:10,240. Anti-VCA-IgM antibody was consistently positive in 5 of the 11 patients; anti-VCA-IgA antibody was consistently positive in 6 of the 10 patients; anti-early antigen (EA)-IgG antibody was consistently positive in...

BACKGROUND The counting of intraepithelial lymphocytes (IELs) in the villous tips of architecturally normal small bowel biopsy specimens was proposed as a method to measure mucosal infiltration in gluten sensitive patients. AIMS To apply this straightforward method in duodenal biopsy specimens from patients affected by potential coeliac disease (PCD) to verify whether it can discriminate thes...