Aging-related anatomical and biochemical changes in lymphatic collectors impair lymph transport, fluid homeostasis, and pathogen clearance.

The role of lymphatic vessels is to transport fluid, soluble molecules, and immune cells to the draining lymph nodes. Here, we analyze how the aging process affects the functionality of the lymphatic collectors and the dynamics of lymph flow. Ultrastructural, biochemical, and proteomic analysis indicates a loss of matrix proteins, and smooth muscle cells in aged collectors resulting in a decrease in contraction frequency, systolic lymph flow velocity, and pumping activity, as measured in vivo in lymphatic collectors.

Visualizing non-lytic exocytosis of Cryptococcus neoformans from macrophages using digital light microscopy.

Many aspects of the infection of macrophages by Cryptococcus neoformans have been extensively studied and well defined. However, one particular interaction that is not clearly understood is non-lytic exocytosis. In this process, yeast cells are released into the extracellular space by a poorly understood mechanism that leaves both the macrophage and Cn viable.

Temporal kinetics and quantitative analysis of Cryptococcus neoformans nonlytic exocytosis.

Cryptococcus neoformans is a facultative intracellular pathogen and the causative agent of cryptococcosis, a disease that is often fatal to those with compromised immune systems. C. neoformans has the capacity to escape phagocytic cells through a process known as nonlytic exocytosis whereby the cryptococcal cell is released from the macrophage into the extracellular environment, leaving both the host and pathogen alive.

The F-Box protein Fbp1 regulates sexual reproduction and virulence in Cryptococcus neoformans.

Cryptococcus neoformans is the leading cause of fungal meningitis in immunocomprised populations. Although extensive studies have been conducted on signal transduction pathways important for fungal sexual reproduction and virulence, how fungal virulence is regulated during infection is still not understood. In this study, we identified the F-box protein Fbp1, which contains a putative F-box domain and 12 leucine-rich repeats (LRR).

Ectopic activation of Mycobacterium tuberculosis-specific CD4+ T cells in lungs of CCR7-/- mice.

Initiation of an adaptive cellular immune response depends on intimate interactions with APCs and naive T lymphocytes. We previously reported that activation of naive Mycobacterium tuberculosis-specific CD4+ T cells depends on dendritic cell (DC) transport of live bacteria from the lungs to the mediastinal lymph node (MDLN). Because the migratory paths of DCs are largely governed by the chemokine receptor CCR7, which is expressed on DCs upon maturation by proinflammatory stimuli, we examined the quantitative contribution of CCR7-dependent DC migration in the context of tuberculosis.

The locus encoding an oligomorphic family of MHC-A alleles (Mane-A*06/Mamu-A*05) is present at high frequency in several macaque species.

Several macaques species are used for HIV pathogenesis and vaccine studies, and the characterization of their major histocompatibility complex (MHC) class I genes is required to rigorously evaluate the cellular immune responses induced after immunization and/or infection. In this study, we demonstrate that the gene expressing the Mane-A*06 allele of pig-tailed macaques is an orthologue of the locus encoding the Mamu-A*05 allele family in rhesus macaques. Analysis of the distribution of this locus in a cohort of 63 pig-tailed macaques revealed that it encodes an oligomorphic family of alleles, highly prevalent (90%) in the pig-tailed macaque population.