Additional file 1: Figure S1. of Lack of neuroinflammation in the HIV-1 transgenic rat: an [18F]-DPA714 PET imaging study

[18F]DPA-714 PET time-activity curves over 60 min derived from the caudate and hippocampus of 3-, 6-, and 9-month-old Tg and WT rats. Error bars represent standard deviation values at each time point. (TIFF 2460 kb

Additional file 1: of Brain 18F-FDG PET of SIV-infected macaques after treatment interruption or initiation

Figure S1. Experimental design diagram for the initiation and interruption cohorts. (TIFF 9496 kb

Paradoxical Immune Responses in Non-HIV Cryptococcal Meningitis

<div><p>The fungus <i>Cryptococcus</i> is a major cause of meningoencephalitis in HIV-infected as well as HIV-uninfected individuals with mortalities in developed countries of 20% and 30%, respectively. In HIV-related disease, defects in T-cell immunity are paramount, whereas there is little understanding of mechanisms of susceptibility in non-HIV related disease, especially that occurring in previously healthy adults. The present description is the first detailed immunological study of non-HIV-infected patients including those with severe central nervous system (s-CNS) disease to 1) identify mechanisms of susceptibility as well as 2) understand mechanisms underlying severe disease. Despite the expectation that, as in HIV, T-cell immunity would be deficient in such patients, cerebrospinal fluid (CSF) immunophenotyping, T-cell activation studies, soluble cytokine mapping and tissue cellular phenotyping demonstrated that patients with s-CNS disease had effective microbiological control, but displayed strong intrathecal expansion and activation of cells of both the innate and adaptive immunity including HLA-DR+ CD4+ and CD8+ cells and NK cells. These expanded CSF T cells were enriched for cryptococcal-antigen specific CD4+ cells and expressed high levels of IFN-γ as well as a lack of elevated CSF levels of typical T-cell specific Th2 cytokines -- IL-4 and IL-13. This inflammatory response was accompanied by elevated levels of CSF NFL, a marker of axonal damage, consistent with ongoing neurological damage. However, while tissue macrophage recruitment to the site of infection was intact, polarization studies of brain biopsy and autopsy specimens demonstrated an M2 macrophage polarization and poor phagocytosis of fungal cells. These studies thus expand the paradigm for cryptococcal disease susceptibility to include a prominent role for macrophage activation defects and suggest a spectrum of disease whereby severe neurological disease is characterized by immune-mediated host cell damage.</p></div

Immunophenotyping demonstrates increased absolute counts of CSF circulating activated HLA-DR+ CD4+ and CD8+ as well as—B-cells in s-CNS patients.

<p>Absolute numbers and proportions of activated CD4+ and CD8+ T lymphocytes (HLA-DR+),—and B lymphocytes were assessed in fresh CSF or blood by flow cytometry as described in Materials and Methods in patients with s-CNS disease (N = 17), non-CNS disease (N = 6), and healthy donors (HD; N = 11). Proportions are calculated from the total CD45+ cells. *0.01≤p<0.05; **0.001≤p<0.01; ***0.0001≤p<0.001.</p

Brain immunofluorescence of autopsy specimens from patients who died of s-CNS cryptococcosis.

<p>Fluorescent macrophage marker (CD68) and fungal marker calcofluor white (CFW) was used to stain cells within the peri-vascular brain parenchyma. Magnification at 10x with inset and scale bar set at 100 μm for 10x images.</p

<i>Ex vivo</i> cryptococcal antigenic stimulation by pulsed autologous mature dendritic cells (mDCs) co-cultured with T lymphocytes from CSF or blood demonstrates compartmentalization of immune responses in a subgroup of 8 s-CNS and 5 non-CNS patients.

<p>(A) Sum of cytokine-producing IFN-γ+, TNF-α+, and IFN-γ+/TNF-α+ CD4+ and CD8+ T lymphocytes (after mDC presentation of MP and Crypto). Events are normalized to fluorescent beads. B) IFN-γ production of activated CD4+ and CD8+ T lymphocytes after Crypto presentation by mDCs. Tc = T lymphocyte; Crypto = glass bead-fractured, heat-killed <i>C</i>. <i>neoformans</i> strain H99; MP = <i>C</i>. <i>neoformans</i> mannoprotein; No Ag = no antigen (un-loaded mDCs). Open circles and bars are representative of non-CNS (Pulmonary) cases, filled circles and bars of s-CNS (CNS) cases. Error bars specify minimum to maximum values. *0.01≤p<0.05; **0.001≤p<0.01; ***0.0001≤p<0.001.</p

Intrathecal cytokine and chemokine profiles reveal elevated IFN-γ and related inflammatory responses in cryptococcosis patients with s-CNS disease compared with non-CNS disease and healthy donors (HD).

<p>CSF was analyzed using Luminex assays according to the Materials and Methods section. (a) IFN-γ, (b) CXCL10 (IP-10), (c) IL-18, (d) TNF-α, (e) IL-10, (f) IL-4, (g) IL-6, (h) IL-13, (i) MCP-1/CCL2, (j) MIP-1α/CCL3, (k) MCP-3/CCL7, and (l) MIP-3β/CCL19. Cytokine and chemokine concentrations were expressed as log₁₀ picogram per milliliter (pg/ml) in s-CNS and non-CNS patients and HD. IL-8, GM-CSF, M-CSF, IL-12p40, IL-17, and IFN-α2 are not shown (without statistically significant differences among case groups). Error bars represent minimum to maximum values. *0.01≤p<0.05; **0.001≤p<0.01; ***0.0001≤p<0.001; ****p<0.0001.</p

Loss in lung volume and changes in the immune response demonstrate disease progression in African green monkeys infected by small-particle aerosol and intratracheal exposure to Nipah virus

<div><p>Nipah virus (NiV) is a paramyxovirus (genus <i>Henipavirus</i>) that emerged in the late 1990s in Malaysia and has since been identified as the cause of sporadic outbreaks of severe febrile disease in Bangladesh and India. NiV infection is frequently associated with severe respiratory or neurological disease in infected humans with transmission to humans through inhalation, contact or consumption of NiV contaminated foods. In the work presented here, the development of disease was investigated in the African Green Monkey (AGM) model following intratracheal (IT) and, for the first time, small-particle aerosol administration of NiV. This study utilized computed tomography (CT) and magnetic resonance imaging (MRI) to temporally assess disease progression. The host immune response and changes in immune cell populations over the course of disease were also evaluated. This study found that IT and small-particle administration of NiV caused similar disease progression, but that IT inoculation induced significant congestion in the lungs while disease following small-particle aerosol inoculation was largely confined to the lower respiratory tract. Quantitative assessment of changes in lung volume found up to a 45% loss in IT inoculated animals. None of the subjects in this study developed overt neurological disease, a finding that was supported by MRI analysis. The development of neutralizing antibodies was not apparent over the 8–10 day course of disease, but changes in cytokine response in all animals and activated CD8+ T cell numbers suggest the onset of cell-mediated immunity. These studies demonstrate that IT and small-particle aerosol infection with NiV in the AGM model leads to a severe respiratory disease devoid of neurological indications. This work also suggests that extending the disease course or minimizing the impact of the respiratory component is critical to developing a model that has a neurological component and more accurately reflects the human condition.</p></div

Brain immunofluorescence of autopsy specimens from patients who died of s-CNS cryptococcosis demonstrates macrophage and T-cell tissue infiltration.

<p>Fluorescent macrophage markers (CD68) and M1 marker (iNOS) and M2 marker (CD200R1) were used to stain cells within the peri-vascular brain parenchyma. DAPI was used for nuclear localization. Magnification at 10x with inset and scale bar set at 100 μm for 10x images.</p

Immunophenotyping demonstrates increased absolute CSF cytotoxic (CD56dim) and immunoregulatory (CD56bright) NK cell populations, monocytes (Mono), and both myeloid (MyDC) and plasmacytoid (PlDC) dendritic cells in CSF of s-CNS patients.

<p>Absolute numbers and proportions of cell types were quantified by flow cytometry in CSF and blood as described in the Materials and Methods section in patients with s-CNS disease (N = 17), non-CNS disease (n = 6), and healthy donors (HD; N = 11). Proportions are calculated from the total CD45+ cells. *0.01≤p<0.05; **0.001≤p<0.01; ***0.0001≤p<0.001.</p