Lymphocytic choriomeningitis virus:An under-recognized congenital teratogen

BACKGROUND Lymphocytic choriomeningitis virus(LCMV)is a neglected rodent-borne arenavirus associated with transplacental transmission and fetal infection.AIM To summarize the epidemiological,clinical,and diagnostic features of reported patients with congenital LCMV infection.METHODS A literature search was conducted in PubMed,Medline,Google Scholar,and ResearchGate.The keywords used were‘congenital lymphocytic choriomeningitis virus,’and 48 studies were included.In addition,we conducted a relevant search by Reference Citation Analysis(RCA)(https://www.referencecitationan alysis.com).RESULTS The results have shown 27 reports of congenital LCMV infection in 86 patients,with 52.73%of them being males.Patients presented with chorioretinitis(83.53%),hydrocephalus(54.12%),and psychomotor retardation or developmental delay(54.12%).Computed tomography and/or magnetic resonance imaging most often demonstrated ventriculomegaly(74.07%),periventricular calcifications(66.67%),and microcephaly(40%).Most mothers of congenitally infected infants were exposed to rodents during pregnancy,predominantly mice,with flu-like symptoms mainly occurring during the first two trimesters of gestation.Mortality in congenitally infected children was 16.47%.The diagnosis of congenital LCMV infection was confirmed serologically in most patients(86.67%).CONCLUSION LCMV is still an insufficiently recognized fetal teratogen that often leads to long-term neurologic sequelae.Clinicians need to be familiar with LCMV and its potential teratogenic effect and as well as to effectively differentiate LCMV from other TORCH(T:Toxoplasma gondii,O:Other pathogens,R:Rubella virus,C:Cytomegalovirus,H:Herpes simplex virus)pathogens.

Trans-presentation of interleukin-15 by interleukin-15 receptor alpha is dispensable for the pathogenesis of autoimmune type 1 diabetes

Interleukin-15(IL-15)is a pro-inflammatory cytokine that is required for the survival and activation of memory CD8^(+)T cells,natural killer(NK)cells,innate lymphoid cells,macrophages and dendritic cells.IL-15 is implicated in the pathogenesis of various autoimmune diseases such as rheumatoid arthritis,inflammatory bowel disease,psoriasis and autoimmune type 1 diabetes(T1D).IL-15 receptor(IL-15R)consists of a specificαchain,theβchain that is shared with IL-2R and the commonγchain.IL-15 is unique in the manner in which it binds and signals through its receptor subunits.IL-15 that is complexed with IL-15Rαbinds to theβγreceptor complex present on the responding cell to mediate its biological effects through a process referred to as trans-presentation.The trans-presented IL-15 is essential to mediate the biological effects on T lymphocytes and NK cells.Here we show that IL-15,but not IL-15Rα,is required for the development of spontaneous and virus-induced T1D,viral clearance and for antigen cross-presentation to CD8^(+)T lymphocytes.Our findings provide insight into the complexities of IL-15 signalling in the initiation and maintenance of CD8^(+)T cell-mediated immune responses.