Intragastric administration of Lactobacillus plantarum and 2,2 '-Dithiodipyridine-inactivated Simian Immunodeficiency Virus (SIV) does not protect Indian rhesus macaques from intrarectal SIV challenge or reduce virus replication after transmission

2018

Article référencé dans le Web of Science WOS:000431998000018

Carnaghan D.G., Mackel J.J., Sweat S.L., Enemuao C.A., Gebru E.H., Dhadvai P., Gangadhara S., Hicks S., Vanderford T.H., Amara R.R., Esparza J., Lu Wei Louis, Andrieu J.M., Silvestri G.

Journal of Virology, 2018, 92 (10), art. no e02030-17 [11 p.] ISSN 0022-538X

A major obstacle to development of an effective AIDS vaccine is that along with the intended beneficial responses, the immunization regimen may activate CD4(+) T cells that can facilitate acquisition of human immunodeficiency virus (HIV) by serving as target cells for the virus. Lu et al. (W. Lu et al., Cell Rep 2:1736-1746, 2012, https://doi.org/10.1016/j.celrep.2012.11.016) reported that intragastric administration of chemically inactivated simian immunodeficiency virus SIVmac239 and Lactobacillus plantarum (iSIV-L. plantarum) protected 15/16 Chinese-origin rhesus macaques (RMs) from high-dose intrarectal SIVmac239 challenge at 3 months postimmunization. They attributed the observed protection to induction of immune tolerance, mediated by "MHC-Ib/E-restricted CD8(+) regulatory T cells that suppressed SIV-harboring CD4(+) T cell activation and ex vivo SIV replication in 15/16 animals without inducing SIV-specific antibodies or cytotoxic T." J.-M. Andrieu et al. (Front Immunol 5:297, 2014, https://doi.org/10.3389/fimmu.2014.00297) subsequently reported protection from infection in 23/24 RMs immunized intragastrically or intravaginally with iSIV and Mycobacterium bovis BCG, L. plantarum, or Lactobacillus rhamnosus, which they ascribed to the same tolerogenic mechanism. Using vaccine materials obtained from our coauthors, we conducted an immunization and challenge experiment with 54 Indian RMs and included control groups receiving iSIV only or L. plantarum only as well as unvaccinated animals. Intrarectal challenge with SIVmac239 resulted in rapid infection in all groups of vaccinated RMs as well as unvaccinated controls. iSIV-L. plantarum-vaccinated animals that became SIV infected showed viral loads similar to those observed in animals receiving iSIV only or L. plantarum only or in unvaccinated controls. The protection from SIV transmission conferred by intragastric iSIV-L. plantarum administration reported previously for Chinese-origin RMs was not observed when the same experiment was conducted in a larger cohort of Indian-origin animals.

Entomologie médicale / Parasitologie / Virologie [052] ; Sciences du monde animal [080] ; Biotechnologies [084]

Fonds IRD [F B010073367]

fdi:010073367