Expression of MxA protein in inflammatory dermatoses.

Abstract

The human MxA protein can be detected in the cytoplasm of IFN-alpha/beta-treated cells, whereas other cytokines, including IFN-gamma, are poor inducers. Because IFN-alpha/beta is predominantly synthesized in response to viral infections, MxA protein should be detectable in virally infected tissue. Biopsy specimens (n = 64) of 12 different dermatoses were therefore screened with an MxA-specific monoclonal antibody on formalin-fixed, paraffin-embedded and microwave-treated tissue sections. As expected, high amounts of MxA protein were found in acute viral skin lesions (chickenpox, Herpes zoster, and Herpes labialis). In addition, MxA protein was also detected in some inflammatory skin lesions of unknown etiology (lupus erythematosus, lichen planus, Schoenlein-Hennoch's anaphylactoid purpura and psoriasis). MxA protein was not found in non-viral infections (bacterial, mycotic, and parasitic) and was also not detectable in various other dermatoses (eczema, scleroderma, urticaria, granulomatous and bullous disorders). MxA staining proved a reliable, sensitive histochemical viral marker for infectious dermatoses. The positive results in non-infectious inflammatory dermatoses might implicate viral involvement or activation of the IFN system by thus far unknown mechanisms.

Secretory Leukocyte Proteinase Inhibitor-Competent DNA Deposits Are Potent Stimulators of Plasmacytoid Dendritic Cells: Implication for Psoriasis

“…Psoriatic skin has a strong IFNI transcriptional fingerprint (e.g., activation of numerous IFNI-inducible genes (37,38)). Moreover, psoriasis patients receiving IFNI therapy for unrelated conditions can develop exacerbated psoriasis symptoms (39,40).…”

Immunohistochemical Evaluation of Mx Protein Expression in Canine Encephalitides

“…31 MxA expression has been demonstrated in human patients infected with a number of viruses, including hepatitis C virus, 8,24 measles virus, 29 adenovirus, 4 cytomegalovirus, 4,44 human immunodeficiency virus (HIV), 19 and herpes simplex virus. 6 In addition to viral infections, MxA expression has been demonstrated in human inflammatory conditions of unknown or suspected autoimmune etiology. 6,7,9,20,34,43 The precise mechanism of MxA's antiviral activity is still unclear.…”

“…6 In addition to viral infections, MxA expression has been demonstrated in human inflammatory conditions of unknown or suspected autoimmune etiology. 6,7,9,20,34,43 The precise mechanism of MxA's antiviral activity is still unclear. Multiple mechanisms are likely involved, depending on the characteristics of the infecting virus.…”

Expression of the interferon-α/β-inducible MxA protein in brain lesions of subacute sclerosing panencephalitis

“…MxA is a stable protein, the half-life of which exceeds 48 h, and remains detectable at significant levels for more than 14 days after INF-a injection [31,32]. The antiviral effects observed for different viruses are ranging from inhibition a step later than primary transcription for influenza virus, over restriction of primary RNA synthesis of VSV [21,22,24] to inhibition of viral protein synthesis in the case of MV [12,26].…”