Figure 1

mCMV-induced micrognathia and abnormal skeletogenesis in mCMV-infected E11 + 10 mandibular processes. A, C. Alcian blue-stained cartilages and alizarin red-stained bone in control (A) and mCMV-infected (C) MANs. mCMV-infected MANs are significantly smaller and exhibit a misshapen Meckel's cartilage with decreased chondrogenesis (arrowheads), reduced mandibular bone osteogenesis (*) and aberrant condylar (c) chondrogenesis, as well as tongue (T) hypoplasia. B, D. Histological analysis. In controls (B), the characteristic rod-shaped Meckel's cartilage (MC) and adjacent ossifying mandibular bone (Mb) are surrounded by mesenchyme (m) which is primarily derived from cranial neural crest. mCMV-infected MAN (D) skeletal components are severely hypoplastic, characterized by a bent and developmentally-delayed Meckel's cartilage, reduced mandibular bone ossification and abnormal condylar (c) formation. Note the presence of clusters of large, pleiomorphic and basophilic stromal cells (arrows) in the periphery and surrounding Meckel's cartilage, mandibular bone and condyle. Bar: A, C: 100 μm; B, D: 50 μm.