T cell engraftment in lymphoid tissues of human peripheral blood lymphocyte reconstituted SCID mice with or without prior activation of cells.

The reconstitution of severe combined immunodeficiency (SCID) mice with human PBL (Hu-PBL-SCID) was assessed using fresh unstimulated PBL and anti-CD3-stimulated PBL. Mice were reconstituted with PBL by intraperitoneal injection of 1-2.5 x 107 PBL in PBS; controls received PBS. Successful engraftment of human PBL in SCID mice was determined by measurement of human IgG in mouse sera, polymerase chain reaction (PCR) detection of human-specific HLA-DRbeta DNA in SCID periphery, and immunohistochemical staining of mouse tissues (spleen, lymph nodes, thymus, liver and lung) with antibodies specific for human CD45 and CD3. Human IgG was detected 1 week after reconstitution in sera of all animals that received at least 1 x 107 PBL and continued to increase for 8 weeks. Human-specific HLA-DRbeta DNA was detected in the majority of mice 3 weeks after reconstitution but not in controls. Moreover, immunohistochemical analysis of Hu-PBL-SCID mouse tissues revealed the presence of human CD45+ cells in all tissues examined. CD3+ T cell engraftment was observed in lymphoid tissues irrespective of whether PBL had been activated prior to transfer or not.