Weiqing Gao

Neural System Antigens Are Recognized by Autoantibodies from Patients Affected by a New Variant of Endemic Pemphigus Foliaceus in Colombia

BackgroundEndemic pemphigus foliaceus (EPF), is also known as “fogo selvagem” or “wild fire,” reflecting the intense burning sensation of the skin reported by patients with this disease. Based on this finding, we tested for neural autoreactivity in patients affected by a new variant of EPF (El Bagre-EPF).MethodsWe tested 20 El Bagre-EPF patients, 20 normal controls from the endemic area, and 20 age- and sex-matched normal controls from outside the endemic area. We tested for autoreactivity to several immunoglobulins and complement. Both human skin and bovine tail were used as antigens.ResultsWe detected autoreactivity to neural structures, mechanoreceptors, nerves, perineural cell layers of the arachnoid envelope around the optic nerve, brain structures, and to neuromuscular spindles; these structures colocalized with several neural markers. The patient antibodies also colocalized with desmoplakins 1 and 2, with the armadillo repeat protein deleted in velo-cardio-facial syndrome and with p0071 antibodies. Autoreactivity was also found associated with neurovascular bundles innervating the skin, and immunoelectron microscopy using protein A gold against patient antibodies was positive against the nerve axons. Paucicellularity of the intraepidermal nerve endings and defragmentation of the neural plexus were seen in 70% of the cases and not in the controls from the endemic area (pu2009<u20090.005). Neuropsychological and/or behavioral symptoms were detected in individuals from the endemic area, including sensorimotor axonal neuropathy.ConclusionsOur findings may explain for the first time the “pose of pemphigus,” representing a dorsiflexural posture seen in EPF patients vis-a-vis the weakness of the extensor nerves, and furthermore, the autoreactivity to nerves in EPF could explain the “burning sensation” encountered in EPF disease.

Serum vascular endothelial growth factor (VEGF) levels correlate with number and location of micrometastases in a murine model of uveal melanoma

Background A preliminary animal study was performed to determine if hepatic micrometastases from uveal melanoma secrete vascular endothelial growth factor (VEGF) that is measurable in serum. Methods We analysed the serum of a C57Bl/6 mouse model of uveal melanoma (n=10) at days 4, 7, 14 and 21 post-inoculation for VEGF levels. We compared the serum VEGF levels with the number and location of hepatic micrometastases and their respective expression of VEGF mRNA. Results Serum VEGF levels rose after inoculation of C57Bl/6 mice eyes with B16LS9 cutaneous melanoma cells. Beginning on day 14 there was a statistically significant (p<0.05) increase in VEGF levels, rising to an average peak level of 37.985u2005pg/ml at day 21. Peak serum VEGF levels correlated with the total number of hepatic micrometastases (R=0.444) and there was moderate correlation of peak VEGF serum levels with micrometastases in more hypoxic locations (R=0.572). VEGF mRNA expression by micrometastases was highest in the most hypoxic regions of the hepatic lobule. Conclusions Hepatic micrometastastic melanoma arising in a mouse model of ocular melanoma secretes VEGF. The number and location of the micrometastases correlate with serum VEGF levels.

Cardiac autoantibodies from patients affected by a new variant of endemic pemphigus foliaceus in Colombia, South America.

Several patients affected by a new variant of endemic pemphigus foliaceus in El Bagre, Colombia (El Bagre-EPF) have experienced a sudden death syndrome, including persons below the age of 50. El Bagre-EPF patients share several autoantigens with paraneoplastic pemphigus patients, such as reactivity to plakins. Further, paraneoplastic pemphigus patients have autoantibodies to the heart. Therefore, we tested 15 El Bagre-EPF patients and 15 controls from the endemic area for autoreactivity to heart tissue using direct and indirect immunofluorescence, confocal microscopy, immunohistochemistry, immunoblotting, and immunoelectron microscopy utilizing heart extracts as antigens. We found that 7 of 15 El Bagre patients exhibited a polyclonal immune response to several cell junctions of the heart, often colocalizing with known markers. These colocalizing markers included those for the area composita of the heart, such as anti-desmoplakins I and II; markers for gap junctions, such as connexin 43; markers for tight junctions, such as ezrin and junctional adhesion molecule A; and adherens junctions, such pan-cadherin. We also detected colocalization of the patient antibodies within blood vessels, Purkinje fibers, and cardiac sarcomeres. We conclude that El Bagre-EPF patients display autoreactivity to multiple cardiac epitopes, that this disease may resemble what is found in patients with rheumatic carditis, and further, that the cardiac pathophysiology of this disorder warrants further evaluation.

Antibodies to pilosebaceous units along their neurovascular supply routes in a new variant of endemic pemphigus foliaceus in Colombia, South America.

Senear Usher syndrome is a variant of pemphigus foliaceus, confined to seborrheic sites and considered to be a clinical overlap syndrome, with features of both pemphigus foliaceus and lupus erythematosus. We recently described autoantibodies to skin eyelid meibomian glands in patients with a new variant of endemic pemphigus foliaceus (El Bagre EPF) in South America. We tested for El Bagre EPF patient sera autoreactivity to pilosebaceous units utilizing direct and indirect immunofluorescence, confocal microscopy, immunohistochemistry and immunoelectron microscopy. Hematoxylin and eosin staining of skin biopsies revealed that one third of the patients affected by El Bagre-EPF demonstrated some histologic alteration of the pilosebaceous units. By immunohistochemistry, most El Bagre EPF biopsies demonstrated evidence of an autoimmune response along the neural and vascular supply routes of the pilosebaceous units. An active immune response was seen with antibodies such as anti-human mast cell tryptase, myeloid/histoid antigen, CD8, CD20, CD68, CD117/c-kit, ZAP-70 and vimentin. Immunoelectron microscopy demonstrated autoantibodies within the hair follicle and at the basement membrane area of the sebaceous glands. El Bagre-EPF patients have autoantibodies to pilosebaceous units and to their surrounding neurovascular packages. Our results warrant further characterization and may explain the loss of hair described in severe endemic pemphigus foliaceus before the therapeutic steroid era.

Varicella-zoster virus (VZV) and alpha 1 antitrypsin: a fatal outcome in a patient affected by endemic pemphigus foliaceus

Backgroundu2002 Herpes virus infections are well known infectious complications of pemphigus and bullous pemphigoid. We describe pathologic findings utilizing autopsy tissue from several organs from a patient affected by a new variant of endemic pemphigus in El Bagre, Colombia, South America.

Residual intraretinal retinoblastoma after chemoreduction failure

Over the past decade, chemoreduction has become the treatment of choice for the initial management of retinoblastoma1. Yet despite its established use, chemoreduction has not been able to treat diffuse infiltrating retinoblastoma, the least common subtype of retinoblastoma1. Herein we report two cases in which residual intraretinal retinoblastoma exhibiting flat and diffuse infiltration was found on pathological exam after a chemoreduction failure. The chemoreduction reduced some of the tumor and unmasked the intraretinal component.

Serum VEGF Levels Correlate with Number and Location of Micrometastases in a Murine Model of Uveal Melanoma

Background A preliminary animal study was performed to determine if hepatic micrometastases from uveal melanoma secrete vascular endothelial growth factor (VEGF) that is measurable in serum. Methods We analysed the serum of a C57Bl/6 mouse model of uveal melanoma (n=10) at days 4, 7, 14 and 21 post-inoculation for VEGF levels. We compared the serum VEGF levels with the number and location of hepatic micrometastases and their respective expression of VEGF mRNA. Results Serum VEGF levels rose after inoculation of C57Bl/6 mice eyes with B16LS9 cutaneous melanoma cells. Beginning on day 14 there was a statistically significant (p<0.05) increase in VEGF levels, rising to an average peak level of 37.985u2005pg/ml at day 21. Peak serum VEGF levels correlated with the total number of hepatic micrometastases (R=0.444) and there was moderate correlation of peak VEGF serum levels with micrometastases in more hypoxic locations (R=0.572). VEGF mRNA expression by micrometastases was highest in the most hypoxic regions of the hepatic lobule. Conclusions Hepatic micrometastastic melanoma arising in a mouse model of ocular melanoma secretes VEGF. The number and location of the micrometastases correlate with serum VEGF levels.

Original article: Serum vascular endothelial growth factor (VEGF) levels correlate with number and location of micrometastases in a murine model of uveal melanoma

Background A preliminary animal study was performed to determine if hepatic micrometastases from uveal melanoma secrete vascular endothelial growth factor (VEGF) that is measurable in serum. Methods We analysed the serum of a C57Bl/6 mouse model of uveal melanoma (n=10) at days 4, 7, 14 and 21 post-inoculation for VEGF levels. We compared the serum VEGF levels with the number and location of hepatic micrometastases and their respective expression of VEGF mRNA. Results Serum VEGF levels rose after inoculation of C57Bl/6 mice eyes with B16LS9 cutaneous melanoma cells. Beginning on day 14 there was a statistically significant (p<0.05) increase in VEGF levels, rising to an average peak level of 37.985u2005pg/ml at day 21. Peak serum VEGF levels correlated with the total number of hepatic micrometastases (R=0.444) and there was moderate correlation of peak VEGF serum levels with micrometastases in more hypoxic locations (R=0.572). VEGF mRNA expression by micrometastases was highest in the most hypoxic regions of the hepatic lobule. Conclusions Hepatic micrometastastic melanoma arising in a mouse model of ocular melanoma secretes VEGF. The number and location of the micrometastases correlate with serum VEGF levels.