These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer‐reviewed by leading experts in the field, making this an essential research companion.

We addressed the role of innate immunity in the protection against HIV-1 infection by studying NK cell function in 37 Vietnamese intravascular drug users (IDUs), who appeared to remain HIV-1 uninfected despite many years of high-risk exposure (exposed uninfected, EU), 10 IDUs who underwent seroconversion and 28 unexposed blood donors. Main results were: NK cell lytic activities against both the NK-susceptible K562 cell line and the NK-resistant Daudi cell line were significantly augmented in EU IDUs compared with either controls or seroconverters before or after seroconversion; NK cells producing the cytokines IFN-γ and TNF-α and the β chemokines CCL3, CCL4, and CCL5 were also increased in the EU IDUs, either after in vitro activation or without stimulation. The finding of an enhanced NK cell function in EU IDUs, especially compared with IDUs who became HIV-1 infected, supports the hypothesis that NK cells contribute to the protection against HIV-1 infection.

Human immunodeficiency virus (HIV) controllers are rare individuals who spontaneously control HIV type 1 replication for 10 years or more in the absence of antiretroviral treatment. In the present study, HIV controllers (n= 11) maintained potent HIV-specific CD4 responses in spite of very low antigenic loads. Their CD4⁺central memory T (T_CM) cells were characterized by near-normal numbers and preserved interleukin-2 (IL-2) secretion in response to HIV antigens and uniformly high expression of the survival receptor IL-7 receptor α (IL-7Rα). Controllers expressed CCR7 at higher levels than uninfected controls, suggesting differences in T_CM-cell homing patterns. CD4⁺effector memory T (T_EM)-cell responses were polyfunctional in HIV controllers, while IL-2 secretion was lost in viremic patients. Cytokine production was three times higher in controllers than in treated patients with undetectable viral loads, suggesting an intrinsically more efficient response in the former group. The total CD4⁺T_EM-cell pool underwent immune activation in controllers, as indicated by increased HLA-DR expression, decreased IL-7Rα expression, a bias towards gamma interferon production upon polyclonal stimulation, and increased macrophage inflammatory protein 1β secretion associated with chronic CCR5 down-regulation. Thus, HIV controllers showed a preserved CD4⁺T_CM-cell compartment and signs of potent functional activation in the CD4⁺T_EM-cell compartment. While controllers did not show the generalized immune activation pattern associated with disease progression, they had signs of immune activation restricted to the effector compartment. These findings suggest the induction of an efficient, nondetrimental type of immune activation in patients who spontaneously control HIV.

Objective— In this article, we studied the effect of acetyl-11-keto-β-boswellic acid (AKβBA), a natural inhibitor of the proinflammatory transcription factor NF-κB on the development of atherosclerotic lesions in apolipoprotein E–deficient (apoE ^−/− ) mice. Methods and Results— Atherosclerotic lesions were induced by weekly LPS injection in apoE ^−/− mice. LPS alone increased atherosclerotic lesion size by ≈100%, and treatment with AKβBA significantly reduced it by ≈50%. Moreover, the activity of NF-κB was also reduced in the atherosclerotic plaques of LPS-injected apoE ^−/− mice treated with AKβBA. As a consequence, AKβBA treatment led to a significant downregulation of several NF-κB–dependent genes such as MCP-1, MCP-3, IL-1α, MIP-2, VEGF, and TF. By contrast, AKβBA did not affect the plasma concentrations of triglycerides, total cholesterol, antioxidized LDL antibodies, and various subsets of lymphocyte-derived cytokines. Moreover, AKβBA potently inhibited the IκB kinase (IKK) activity immunoprecipitated from LPS-stimulated mouse macrophages and mononuclear cells leading to decreased phosphorylation of IκBα and inhibition of p65/NF-κB activation. Comparable AKβBA-mediated inhibition was also observed in LPS-stimulated human macrophages. Conclusion— The inhibition of NF-κB activity by plant resins from species of the Boswellia family might represent an alternative for classical medicine treatments for chronic inflammatory diseases such as atherosclerosis. (Arterioscler Thromb Vasc Biol. 2008;28:272-277)