Use of a lentivirus/VSV pseudotype virus for highly efficient genetic redirection of human peripheral blood lymphocytes

High transfection efficiency and cell viability of immune cells with nanomaterials-based transfection reagent

Gene manipulation in non-adhesive cells, especially lymphocytes, was difficult due to their low efficiency and high toxicity. Electroporation was reported as a highly efficient method for human and mouse lymphocytes. However, this method requires expensive equipment and causes severe cell damage. Here, the authors present a simple and efficient method to deliver siRNA into lymphocytes with high efficiency and cell viability. This nanomaterials-based transfection reagent was simple and cost-effective and can perform multiple transfections, which further increase the overall efficiency. This method should be applicable for many cell lines and can be used to decipher gene functions of lymphocytes.

Genetic redirection of T cells for cancer therapy

Adoptive immunotherapy can induce dramatic tumor regressions in patients with melanoma or viral-induced malignancies, but extending this approach to many common cancers has been hampered by a lack of naturally occurring tumor-specific T cells. In this review, we describe recent advances in the genetic modification of T cells using genes encoding cell-surface receptors specific for tumor-associated antigen. Using genetic modification, the many functional properties of T cells, including cytokine secretion and cytolytic capacity, are redirected from their endogenous specificity toward the elimination of tumor cells. Advances in gene design, vectors, and cell production are discussed, and details of the progress in clinical application of this approach are provided.

Upregulated BclG(L) expression enhances apoptosis of peripheral blood CD4+ T lymphocytes in patients with systemic lupus erythematosus

Increased lymphocyte apoptosis has been suggested to contribute to the development of systemic lupus erythematosus (SLE), but the critical factors involved in the apoptotic pathways are still unknown. By long serial analysis of gene expression (LongSAGE) profiles and microarray analyses, a novel apoptosis-related gene BclG(L) expression was found significantly increased in peripheral blood CD4+ T cells of SLE patients, which was correlated with the enhanced CD4+ T cells apoptosis, anti-nuclear antibody (ANA) titer and proteinuria. In vitro, BclG(L) expression could be specially upregulated by SLE serum stimulation and positively correlated with induced CD4+ T cell apoptosis. Enforcing BclG(L) overexpression by lentivirus could directly enhance CD4+ T cell apoptosis, but these apoptosis-inducing effects could be partially inhibited by knockdown of BclG(L) expression. Collectively, these results indicate that increased BclG(L) expression may contribute to the aberrant CD4+ T cell apoptosis which causes an inappropriate immune response and impaired homeostasis in SLE.

The analysis of the functions of human B and T cells in humanized NOD/shi-scid/gammac(null) (NOG) mice (hu-HSC NOG mice)

'Humanized mice' are anticipated to be a valuable tool for studying the human immune system, but the reconstituted human immune cells have not yet been well characterized. Here, we extensively investigated the differentiation and functions of human B and T cells in a supra-immunodeficient mouse strain, NOD/shi-scid/gammac(null) (NOG) reconstituted with CD34(+) hematopoietic stem cells obtained from umbilical cord blood. In these hu-HSC NOG mice, the development of human B cells was partially blocked, and a significant number of B-cell progenitors accumulated in the spleen. The mature CD19(+)IgM(+)IgD(+) human B cells of the hu-HSC NOG mice could produce IgG in vivo and in vitro by antigenic stimulation. In contrast, although human T cells with an apparently normal phenotype developed, most of them could neither proliferate nor produce IL-2 in response to antigenic stimulation by anti-CD3 and anti-CD28 antibodies in vitro. The positive selection of human T cells in the thymus was sufficiently functional, if not complete, and mainly mediated by mouse class II, suggesting that the human T cells lost their function in the periphery. We found that multiple mechanisms were involved in the T-cell abnormalities. Collectively, our results demonstrate that further improvements are necessary before humanized mice with a functional human immune system are achieved.