Low frequency of human papillomavirus infection in conjunctival squamous cell carcinoma of Mexican patients.

BACKGROUND: The relationship between Human Papillomavirus (HPV) infection and conjunctiva cancer is controversial. HPV detection will provide more information about the role of this infectious agent in the biology of conjunctiva cancer. In the present study, DNA extracted and purified from 36 Conjunctival Squamous Cell Carcinomas (CSCC) was evaluated by PCR for HPV DNA sequences. The results were correlated with the clinical and histopathological variables. RESULTS: The results showed that HPV DNA was present in 8 CSCC samples (22%); HPV16 was the sole type detected. Significant association was found between HPV detection and the limbus tumor subtype (p = 0.03). All the samples were non-metastatic squamous cell carcinoma. CONCLUSIONS: The HPV presence in CSCC from Mexican patients is not a common event.

Ocular involvement and blindness secondary to linear IgA dermatosis.

A 43-year-old man with linear immunoglobulin A (IgA) dermatosis associated with gluten intolerance presented with progressive vision loss, pain and photosensitivity in both eyes. His visual acuity was light perception (LP) in both eyes. A physical examination revealed bullous, papular lesions with erythematous borders in periocular tissues, limbs, and thorax. Slit-lamp examination showed conjunctival hyperemia, fibrosis, corneal opacification, and vascularization with epithelial defects. Immunofluorescent skin and corneal surface biopsy studies showed linear IgA deposits. The patient was treated with keratolimbal allogenic transplantation and cryopreserved amniotic membrane in the right eye. Regardless of the treatment he persisted with torpid evolution developing retinal and choroidal detachments. After these events he was started on intravenous immune globulin (IVIG) and showed very slight improvement in ocular surface. These types of blistering diseases are rare in the eye. Even when adequate local treatment is given, systemic treatment is mandatory and ocular prognosis can be unsatisfactory.

Study of the expression of CD30 in pterygia compared to healthy conjunctivas.

PURPOSE: The pterygium is characterized by a fibrovascular neoformation from the bulbar conjunctiva into the cornea. The recent discovery that abnormal markers associated with tumor diseases are identified in the pterygium strengthens the theory that the pterygium is a tumor-like disease rather than a degenerative disease. The CD30 molecule has been identified in neoplastic and normal epithelial proliferating cells. The aim of this study was to determine the expression of the CD30 molecule in the pterygium. METHODS: Immunohistochemical staining using an antibody to CD30 and to the Ki-67 nuclear antigen was performed on 25 pterygial specimens and 10 healthy conjunctivas. RESULTS: Strong immunostaining against CD30 was observed in all pterygium specimens, in contrast to the healthy conjunctivas that showed weak immono-positivity in only three cases. The staining was diffused, predominantly to the basal epithelium. The Ki-67 antigen was observed in the nucleus of the basal epithelium of the pterygial specimens, and no staining was observed in the healthy conjunctiva. When serial sections were stained with CD30 and Ki-67, the cells that expressed CD30 also expressed Ki-67. CONCLUSIONS: The present study identified for the first time the existence of CD30 molecules in the basal epithelium of a pterygium. The fact that the positivity to Ki-67 in the basal epithelium of the pterygium correlated with the CD30 reactivity suggested that this protein could be associated with the uncontrolled cell proliferation of the epithelium in this pathology. The CD30 molecule could therefore be a suitable target to be inhibited using chimerical antibodies in pterygium diseases.

Comparative expression analysis of aquaporin-5 (AQP5) in keratoconic and healthy corneas.

PURPOSE: Keratoconus (KC) is a common progressive corneal disease characterized by excessive stromal thinning, central or paracentral conical protrusion, and disruptions in Bowman's layer. The etiology of KC is largely unknown, and a combination of genetic and environmental factors is believed to play a role in the origin of the disease. Recently, the absence of transcripts of the water channel, aquaporin-5 (AQP5), was demonstrated by reverse-transcription polymerase chain reaction (RT-PCR) in KC tissues and was proposed as a possible marker for KC. In this study, we sought to evaluate AQP5 mRNA and protein expression in KC and non-KC corneal tissues using a combination of techniques. METHODS: A total of 69 samples of corneal tissue were analyzed including 39 corneal buttons from patients with advanced KC, 16 samples of non-KC corneal epithelium belonging to patients who underwent surface refractive surgery, 12 sclerocorneal rims obtained from healthy donor subjects, and two healthy corneal buttons. Determination of AQP5 transcript and protein expression patterns was performed by means of real time RT-PCR, immunohistochemistry, immunocytochemistry, and flow cytometry methods. Cell culture was performed to identify AQP5 protein expression in KC epithelial cells. RESULTS: AQP5 mRNA was expressed with no significant differences between KC and non-KC tissues. Moreover, AQP5 protein expression analysis did not reveal differences in protein levels and/or cell location among KC and non-KC tissues. Interestingly, AQP5 expression continues for up to 21 days in the isolated KC corneal epithelial cells. CONCLUSIONS: Our results do not support a role for AQP5 in KC etiopathogeny or as a disease marker. Genetic background differences or a distinct pathogenetic KC cascade specific to the analyzed population could account for the dissimilarities observed in KC-related AQP5 expression.