How cotransplantation of different classes of CCR7-null hematopoietic cells contribute to a cellular and cytokine microenvironment in the lungs of host animals that can efficiently respond to an A fumigatus infection. HSC indicates hematopoietic stem cells; CMP, common myeloid progenitors; GMP, granulocyte-monocyte progenitors; DC, dendritic cells; M, monocytes; MO, macrophages; pDC, plasmacytoid DC; T, T cells; and B, B cells. (Professional illustration by Marie Dauenheimer.)