ABSTRACT
BACKGROUND: Alpha-toxin (AT), a major virulence factor of Staphylococcus aureus, is an important immunotherapeutic target to prevent or treat invasive S. aureus infections. Previous studies have suggested that anti-AT antibodies (Abs) may have a protective role against S. aureus bacteremia (SAB), but their function remains unclear. Therefore, we aimed to investigate the association between serum anti-AT Ab levels and clinical outcomes of SAB. METHODS: Patients from a prospective SAB cohort at a tertiary-care medical center (n = 51) were enrolled in the study from July 2016 to January 2019. Patients without symptoms or signs of infection were enrolled as controls (n = 100). Blood samples were collected before the onset of SAB and at 2- and 4-weeks post-bacteremia. Anti-AT immunoglobin G (IgG) levels were measured using an enzyme-linked immunosorbent assay. All clinical S. aureus isolates were tested for the presence of hla using polymerase chain reaction. RESULTS: Anti-AT IgG levels in patients with SAB before the onset of bacteremia did not differ significantly from those in non-infectious controls. Pre-bacteremic anti-AT IgG levels tended to be lower in patients with worse clinical outcomes (7-day mortality, persistent bacteremia, metastatic infection, septic shock), although the differences were not statistically significant. Patients who needed intensive care unit care had significantly lower anti-AT IgG levels at 2 weeks post-bacteremia (P = 0.020). CONCLUSION: The study findings suggest that lower anti-AT Ab responses before and during SAB, reflective of immune dysfunction, are associated with more severe clinical presentations of infection.
Subject(s)
Bacteremia , Staphylococcal Infections , Humans , Staphylococcus aureus , Prospective Studies , Antibody Formation , Bacteremia/drug therapy , Staphylococcal Infections/drug therapy , Immunoglobulin G , Anti-Bacterial Agents/therapeutic useSubject(s)
Cross Infection , Methicillin-Resistant Staphylococcus aureus , Oxazolidinones , Sepsis , Staphylococcal Infections , Humans , Oxazolidinones/pharmacology , Anti-Bacterial Agents/pharmacology , Staphylococcal Infections/diagnosis , Staphylococcal Infections/drug therapy , Microbial Sensitivity TestsABSTRACT
Dopamine cells derived from neural stem cells were transplanted into the dopamine-denervated striatum in the rat. Survival of the dopamine cells, gliosis, and immunological reaction were examined by immunostaining. Tyrosine hydroxylase immunoreactive (TH+) cells were seen in the needle tract, walls of the lateral ventricle, thalamus, hippocampus, and external and internal capsules for up to 3 weeks examination. Most TH+ cells had mature-looking polygonal shapes with processes. Some cells migrated into the striatum. Behavioral improvement was not seen