The Proteome of Biologically Active Membrane Vesicles from Piscirickettsia salmonis LF-89 Type Strain Identifies Plasmid-Encoded Putative Toxins

Piscirickettsia salmonis is the predominant bacterial pathogen affecting the Chilean salmonid industry. This bacterium is the etiological agent of piscirickettsiosis, a significant fish disease. Membrane vesicles (MVs) released by P. salmonis deliver several virulence factors to host cells. To improve on existing knowledge for the pathogenicity-associated functions of P. salmonis MVs, we studied the proteome of purified MVs from the P. salmonis LF-89 type strain using multidimensional protein identification technology. Initially, the cytotoxicity of different MV concentration purified from P. salmonis LF-89 was confirmed in an in vivo adult zebrafish infection model. The cumulative mortality of zebrafish injected with MVs showed a dose-dependent pattern. Analyses identified 452 proteins of different subcellular origins; most of them were associated with the cytoplasmic compartment and were mainly related to key functions for pathogen survival. Interestingly, previously unidentified putative virulence-related proteins were identified in P. salmonis MVs, such as outer membrane porin F and hemolysin. Additionally, five amino acid sequences corresponding to the Bordetella pertussis toxin subunit 1 and two amino acid sequences corresponding to the heat-labile enterotoxin alpha chain of Escherichia coli were located in the P. salmonis MV proteome. Curiously, these putative toxins were located in a plasmid region of P. salmonis LF-89. Based on the identified proteins, we propose that the protein composition of P. salmonis LF-89 MVs could reflect total protein characteristics of this P. salmonis type strain

A new class of inverse Gaussian type distributions

Elliptical distributions, Diagnostics, Kurtosis, Likelihood methods, Moments,

Resident memory T cells are a cellular reservoir for HIV in the cervical mucosa

HIV viral reservoirs are established very early during infection. Resident memory T cells (TRM) are present in tissues such as the lower female genital tract, but the contribution of this subset of cells to the pathogenesis and persistence of HIV remains unclear. Here, we show that cervical CD4+TRM display a unique repertoire of clusters of differentiation, with enrichment of several molecules associated with HIV infection susceptibility, longevity and self-renewing capacities. These protein profiles are enriched in a fraction of CD4+TRM expressing CD32. Cervical explant models show that CD4+TRM preferentially support HIV infection and harbor more viral DNA and protein than non-TRM. Importantly, cervical tissue from ART-suppressed HIV+ women contain high levels of viral DNA and RNA, being the TRM fraction the principal contributor. These results recognize the lower female genital tract as an HIV sanctuary and identify CD4+TRM as primary targets of HIV infection and viral persistence. Thus, strategies towards an HIV cure will need to consider TRM phenotypes, which are widely distributed in tissues.We would like to thank all the patients who participated in the study and their providers. We thank José L. Poza, Mª Elena Suárez, Mª Assumpció Pérez-Benavente and Cristina Carrato for referral of patients and sample collection, Irian Lorencés and Laia Pérez-Roca from the Tumor Bank of the IGTP-HUGTiP for sample management, Alba Ruiz and Ruth Peña for generating the viral stock R5-Bal and Gerard Requena from the Flow Cytometry Facility at the IGTP for excellent technical assistance, as well as Isabel Crespo from the Flow Cytometry Platform at the IDIBAPS for her excellent technical assistance on Amnis technology. This work was primarily supported by grants from the Spanish “Ministerio de Economía y Competitividad, Instituto de Salud Carlos III” (ISCIII, PI14/01235 and PI17/01470) and a fellowship award from the Dexeus foundation for women’s health research to M.G., grants R21AI118411 and SAF2015-67334-R (from the Spanish Secretariat of Science and Innovation and FEDER funds) to M.J.B and grants from the ISCIII (PI14/01058 and PI17/00164) to J.G.P. M.G., M.J.B., and. J.G.P. are supported by the Spanish AIDS network Red Temática Cooperativa de Investigación en SIDA (RD16/0025/0007) M.G. is currently supported by the “Pla estratègic de recerca i innovació en salut” (PERIS, SLT002/16/00353), from the Catalan government, while the Miguel Servet program from the ISCIII supports M.J.B. (CP17/00179) and J.G.P. (CP15/00014)

Resident memory T cells are a cellular reservoir for HIV in the cervical mucosa

HIV viral reservoirs are established very early during infection. Resident memory T cells (T) are present in tissues such as the lower female genital tract, but the contribution of this subset of cells to the pathogenesis and persistence of HIV remains unclear. Here, we show that cervical CD4T display a unique repertoire of clusters of differentiation, with enrichment of several molecules associated with HIV infection susceptibility, longevity and self-renewing capacities. These protein profiles are enriched in a fraction of CD4T expressing CD32. Cervical explant models show that CD4T preferentially support HIV infection and harbor more viral DNA and protein than non-T. Importantly, cervical tissue from ART-suppressed HIV women contain high levels of viral DNA and RNA, being the T fraction the principal contributor. These results recognize the lower female genital tract as an HIV sanctuary and identify CD4T as primary targets of HIV infection and viral persistence. Thus, strategies towards an HIV cure will need to consider T phenotypes, which are widely distributed in tissues