Although not the cause of the outbreak, LCMV was found to be a cause of nonbacterial or aseptic meningitis.In 1996, Peter Doherty and Rolf Zinkernagel shared the Nobel Prize in Medicine and Physiology, for their work with LCMV which led to a fundamental understanding of the adaptive immune response, MHC restriction. In the 1970s, studies concerning the importance of MHC locus were done exclusively in transplantation and tumor rejection. Taking this into consideration, Doherty and Zinkernagel were working on the response of mice to virus infections. They observed that T-cell receptors must recognise a complex of foreign antigen and an MHC antigen in order to destroy infected cells. Their key experiment involved harvesting of splenocytes containing LCMV-specific cytotoxic T lymphocytes(CTL) from an infected mouse strain A. These were then mixed in vitro with virus infected fibroblasts or macrophages from two different mouse strains, A and B. By the method of Cr-release cytotoxicity assay, thereby tagging the CTL with chromium-51 (Cr-51), the CTL destruction of infected cells was quantified by release of Cr-51. The results showed that CTL killed only the infected cells from strain A, and they did not lyse uninfected cells or infected cells from strain B. They concluded that these virus specific CTLs only lyse cells carrying the same molecules of the major histocompatibility site (MHC) as the CTLs themselves. Thus, the virus-specific CTLs are "MHC-restricted". This discovery lead to a greater understanding of an important aspect of the immune system. Spread
LCMV is naturally spread by the common house mouse, Mus musculus.
However most unilateral cases will eventually progress to include both sides of the larynx, a more serious problem with symptoms appearing more often. Signs are usually worse in hot and humid weather, during exercise, during times of stress or excitement, and in obese pets. Acute or late-stage symptoms are usually unmistakable and require immediate emergency treatment. Diagnosis
This condition is usually diagnosed by direct examination of the larynx under light sedation, which also allows checking for benign or malignant tumors. Tests, such as thoracic radiographs, CT-scans, or echocardiography, are sometimes needed to rule out heart, lung, or mediastinal diseases or other possible causes of the symptoms often seen with LP. Some vets may also recommend running a thyroid profile since LP can be a symptom or complication of hypothyroidism. Treatment
Mild cases are managed by limiting activity, keeping a healthy body weight, and avoiding exposure to high ambient temperatures. Mild sedatives can be used to decrease anxiety and panting and therefore improve respiration. Corticosteroids may also be administered in acute cases to decrease inflammation and edema of the larynx. Severe acute symptoms, such as difficulty breathing, hyperthermia, or aspiration pneumonia, must be stabilized with sedatives and oxygen therapy and may require steroid or antibiotic medications. Sometimes a tracheotomy is required to allow delivery of oxygen. Once the patient is stabilized, surgical treatment may be beneficial especially when paralysis occurs in both arytenoid cartilages (bilateral paralysis). The surgery (aretynoid lateralization, or a "laryngeal tieback") consists of suturing one of the aretynoid cartilages in a maximally abducted (open) position.