Human tonsil implants xenotransplanted in SCID mice display broad lymphocytic diversity and cellular activation profile similar to those in the original lymphoid organ.

Background: Models consisting of human immune cells in suspension transferred to severe combined immune deficient (SCID) mice have been invaluable for studying immune response, autoimmunity, and lymphomagenesis. The dissemination of human cells within the mouse body hampers immune functionality with time and favorites the development of human graft vs. mouse host (GvH) disease.

Human peripheral blood leukocyte engraftment into SCID mice: critical role of CD4(+) T cells.

We examined the influence of donor T lymphocytes on human peripheral blood leukocytes (PBL) engraftment into severe combined immune deficient (SCID) mice. Mice were injected with unfractionated or subset-depleted human PBL, and treated at various times with OKT3, a cytotoxic monoclonal antibody against human CD3(+) T lymphocytes. PBL engraftment, high levels of human Ig, and high incidence of lymphoproliferative disease (lpd) were found in mice transplanted with unfractionated PBL and CD8- or CD14-depleted PBL, and in mice treated with OKT3 at distance from PBL transfer.

Epstein-Barr virus-dependent lymphoproliferative disease: critical role of IL-6.

Epstein-Barr virus (EBV)-induced lymphoproliferative disease (lpd) is a B cell neoplasm that affects patients who are immunosuppressed in the context of organ transplantation or HIV infection. A model for the aggressive form of this entity was generated by xenotransplantation of SCID mice with human peripheral blood leukocytes from individuals with prior contact with EBV. This model, where large B cell lymphoma occurs, was used to test the hypothesis that IL-6 has a major role in EBV-induced B cell tumorigenesis.

Human adult tonsil xenotransplantation into SCID mice for studying human immune responses and B cell lymphomagenesis.

Objective: To generate a human-mouse xenochimeric model where human cells remain clustered in the animal to optimize their interactions and recovery.

Materials And Methods: Severe combined immune deficient mice (SCID) were xenografted subcutaneously with human adult tonsil pieces (hu-ton-SCID mice). Such animals were: (a) compared with those receiving tonsil cells in suspension, and (b) immunized with de novo and recall antigens.

Antithrombotic and anticoagulant activities of a low molecular weight fucoidan by the subcutaneous route.

Fucoidans (high-molecular-weight sulfated polysaccharides extracted from brown seaweeds) have anticoagulant and antithrombotic effects. They inhibit thrombin by catalyzing both serpins (antithrombin and heparin cofactor II) according to their chemical structures and origins. In this study, a low-molecular-weight (LMW) fucoidan of 8 kDa was obtained by chemical degradation of a high-molecular-weight fraction.