IFNG and hemophagocytic syndrome: These observations were highly relevant as they reflected the occurrence of IFN-γ-independent HLH-like disease in a number of interesting case reports (reviewed in references [32] and [33]), but were in clear contrast with data from primary HLH models, in which IFN-γ was designated as the key pathogenic cytokine since its depletion resulted in complete inhibition of the fatal HLH-like syndrome [8, 34].