Targeting ABL1 or ARG Tyrosine Kinases to Restrict HIV-1 Infection in Primary CD4+ T-Cells or in Humanized NSG Mice.

Background: Previous studies support dasatinib as a potent inhibitor of HIV-1 replication. However, a functional distinction between 2 kinase targets of the drug, ABL1 and ARG, has not been assessed.

Setting: We used primary CD4 T-cells, CD8-depleted peripheral blood mononuclear cells (PBMCs) from a treatment naïve HIV-1 patient, and a humanized mouse model of HIV-1 infection.

Neisseria gonorrhoeae co-infection exacerbates vaginal HIV shedding without affecting systemic viral loads in human CD34+ engrafted mice.

HIV synergy with sexually transmitted co-infections is well-documented in the clinic. Co-infection with Neisseria gonorrhoeae in particular, increases genital HIV shedding and mucosal transmission. However, no animal model of co-infection currently exists to directly explore this relationship or to bridge the gap in understanding between clinical and in vitro studies of this interaction.

Control of HIV Infection In Vivo Using Gene Therapy with a Secreted Entry Inhibitor.

HIV entry inhibitors are highly effective in controlling virus replication. We have developed a lentiviral vector that expresses a secreted entry inhibitor, soluble CD4 (sCD4), which binds to the HIV envelope glycoproteins and inactivates the virus. We have shown that sCD4 was secreted from gene-modified CD4 T cells, as well as from human umbilical cord blood-derived CD34 hematopoietic stem/progenitor cells (HSPCs), and protected unmodified HIV target cells from infection in vitro.

IVIG regulates the survival of human but not mouse neutrophils.

Intravenous immunoglobulin (IVIG) are purified IgG preparations made from the pooled plasma from thousands of healthy donors and are being tested in preclinical mouse models. Inherent challenges, however, are the pluripotency of IVIG and its xenogeneicity in animals. IVIG can alter the viability of human neutrophils via agonistic antibodies to Fas and Siglec-9.

Optimal attenuation of experimental autoimmune encephalomyelitis by intravenous immunoglobulin requires an intact interleukin-11 receptor.

Background: Intravenous immunoglobulin (IVIg) has been used to treat a variety of autoimmune disorders including multiple sclerosis (MS); however its mechanism of action remains elusive. Recent work has shown that interleukin-11 (IL-11) mRNAs are upregulated by IVIg in MS patient T cells. Both IVIg and IL-11 have been shown to ameliorate experimental autoimmune encephalomyelitis (EAE), an animal model of MS.

Cytokine profiles in mouse models of experimental immune thrombocytopenia reveal a lack of inflammation and differences in response to intravenous immunoglobulin depending on the mouse strain.

Background: Mouse models of human immune thrombocytopenia (ITP) have been used for years to investigate the mechanism of intravenous immunoglobulin (IVIG) to ameliorate ITP; however, how closely these experimental mouse models mirror the human autoimmune inflammatory disease is unclear. The aim of this study was to assess the cytokine profiles in experimental ITP with and without IVIG treatment.

Study Design And Methods: We examined the production of 23 cytokines that included pro- and anti-inflammatory cytokines, in two different mouse strain models of ITP, BALB/c and C57BL/6J, with and without IVIG treatment.

Therapeutic effect of IVIG on inflammatory arthritis in mice is dependent on the Fc portion and independent of sialylation or basophils.

High-dose i.v. Ig (IVIG) is used to treat various autoimmune and inflammatory diseases; however, the mechanism of action remains unclear.

Mouse background and IVIG dosage are critical in establishing the role of inhibitory Fcγ receptor for the amelioration of experimental ITP.

A recognized paradigm for the therapeutic action of intravenous immunoglobulin (IVIG) in immune thrombocytopenia (ITP) involves up-regulation of the inhibitory Fcγ receptor (FcγRIIB) in splenic macrophages. However, published data have indicated that opposing results are obtained when using FcγRIIB-deficient mice on different strain backgrounds. Herein we show BALB/c FcγRIIB(-/-) and wild-type, with or without spleens, all recover ITP with similar dynamics after IVIG (1 g/kg) treatment; however, this was not the case for C57BL/6 (B6) FcγRIIB(-/-).

Sialylation-independent mechanism involved in the amelioration of murine immune thrombocytopenia using intravenous gammaglobulin.

Background: Sialylation of the N-linked glycan on asparagine-297 within the Fc region of intravenous gammaglobulins (IVIgs) was shown to be necessary for efficacy of IVIg in the amelioration of experimental inflammatory arthritis. To test the role for Fc sialylation of IVIg in immune modulating therapies beyond the K/BxN arthritis model, we examined the efficacy of sialylated compared to nonsialylated IVIg for the ability to attenuate immune thrombocytopenia (ITP) in a mouse model that approximates the clinical setting of human ITP.

Study Design And Methods: We used a published, passive anti-platelet (PLT) dose-escalation mouse model of ITP that approximates clinical ITP.

Improved mouse models for the study of treatment modalities for immune-mediated platelet destruction.

Background: We found when using a mouse model of immune thrombocytopenia (ITP) that platelet (PLT) nadir could not be maintained in the face of daily PLT antibody, making interpretation of treatment modalities difficult. This finding was documented to be at least in part due to increased thrombopoiesis as a result of a compensated thrombocytolytic state. Thus, it was important to develop an improved mouse model of human ITP so as to maintain PLT nadir over time.