Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022568 (keratitis)
 5,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Viruses are suspected but usually unproven triggering factors in autoimmunity. One favored mechanism to explain the role of viruses in the genesis of autoimmunity is molecular mimicry. An immunoinflammatory blinding lesion called herpetic stromal keratitis (HSK) that follows ocular infection with herpes simplex virus (HSV) is suggested to result from a CD4(+) T-cell response to a UL6 peptide of HSV that cross-reacts with a corneal autopeptide shared with the immunoglobulin G2a(b) (IgG2a(b)) isotype. The present report reevaluates the molecular mimicry hypothesis to explain HSK pathogenesis. Our results failed to reveal cross-reactivity between the UL6 and IgG2a(b) peptides or between peptide reactive T cells and HSV antigens. More importantly, animals infected with HSV failed to develop responses that reacted with either peptide, and infection with a recombinant vaccinia UL6 vector failed to cause HSK, in spite of generating UL6 reactivity. Other lines of evidence also failed to support the molecular mimicry hypothesis, such as the failure to affect HSK severity upon tolerization of susceptible BALB/c and B-cell-deficient mice with IgG2a(b) or UL6 peptides. An additional study system revealed that HSK could be induced in mouse strains, such as the OT2 x RAG1(-/-) mice (T cell receptor transgenic recognizing OVA(323-339)) that were unable to produce CD4(+) T-cell responses to any detectable HSV antigens. Our results cast doubt on the molecular mimicry hypothesis as an explanation for the pathogenesis of HSK and indicate that if autoimmunity is involved its likely proceeds via a bystander activation mechanism.
 ...
PMID:Herpes simplex virus-induced keratitis: evaluation of the role of molecular mimicry in lesion pathogenesis. 1123 34

Although smallpox was eradicated worldwide, concerns have been raised about the use of smallpox as a biological weapon. Plans are being considered for smallpox immunization in the United States. Variola virus, the cause of smallpox, and vaccinia virus, used in smallpox immunization, are both orthopoxviruses that are associated with serious ocular complications, including eyelid and conjunctival infection, corneal ulceration, disciform keratitis, iritis, optic neuritis, and blindness. About 5% to 9% of patients with smallpox develop ocular complications, and case-fatality rates reach 20% to 35% among unvaccinated individuals. About 10 to 20 patients develop ocular complications per 1 million smallpox immunizations, usually through autoinoculation, in which the patient transfers vaccinia from the immunization site to the eye. The risk of ocular vaccinia infection may be reduced by instructing patients and individuals in close contact with the vaccinee to wash their hands often and avoid touching the immunization site and their eyes. Topical antiviral therapy, topical steroids, and topical and oral antibiotics have been used to reduce the ocular complications of smallpox immunization. In contrast, there has been little experience with the use of these therapies for the ocular complications of smallpox.
 ...
PMID:The ocular complications of smallpox and smallpox immunization. 1536 30

5-Trifluoromethyl-2'-deoxyuridine (F(3)TDR) has potent therapeutic antiviral activity in herpes simplex infection of the rabbit cornea with strains of herpes virus both sensitive and resistant to 5-iodo-2'-deoxyuridine, and in corneal infection with vaccinia. 5-Trifluoromethyl uracil is not therapeutically active in herpetic keratitis.
 ...
PMID:THERAPEUTIC ANTIVIRAL ACTION OF 5-TRIFLUOROMETHYL-2'-DEOXYURIDINE IN HERPES SIMPLEX KERATITIS. 1416 83

Because smallpox may be a weapon, immunization programs have been restarted and research continues with vaccinia (smallpox vaccine). Ocular complications occur in 5 to 9% of those who contract smallpox and in 10 to 20 per million vaccinia recipients through self-inoculation or from contact with vaccinated individuals. Both variola virus (smallpox) and vaccinia virus (smallpox vaccine) are orthopoxviruses that can cause conjunctival and eyelid infections, cornea ulceration, keratitis, iritis, optic neuritis, and loss of vision. Clinicians should maintain a high index of suspicion for smallpox vaccine-associated reactions in vaccinia researchers, the immunized, and their close contacts. A researcher sprayed vaccinia in her eye. Timely irrigation may have prevented a viral infection. The possibility that this individual had self-immunized herself with smallpox vaccine via the conjunctiva and preventive measures are discussed. Greater precautionary measures need to be taken to prevent laboratory accidents. Antiviral ophthalmic medication and vaccinia-immune globulin medication are treatment options.
 ...
PMID:Prevention of vaccinia infection in a laboratory worker. 1798 78


<< Previous 1 2