Biopsy specimens from 11 patients with lichen planus have been studied by electron microscopy to see if changes could be revealed which would indicate the etiology of this condition.
Apart from inflammatory cells no abnormality was detected in the dermis. The basal lamina frequently showed multiplication and breaks. Tonofibrils lost their electron density, regular arrangement, and in advanced stages attachment to desmosomes. Breakdown of desmosomes and half-desmosomes occurred at all stages of the disease. Two types of intranuclear structures which have not been found in normal material were seen. One of these was lamellar in appearance and the other consisted of a membrane-bound mass of granular material. On morphological grounds there was no evidence that either of these was viral in nature, the latter, however, had an appearance similar to mycoplasma.
Johnson FR, Fry L. Ultrastructural Observations on Lichen Planus. Arch Dermatol. 1967;95(6):596-607. doi:10.1001/archderm.1967.01600360042006