Inactivation of simian immunodeficiency virus by hydrostatic pressure.

Abstract

The inactivation of the simian immunodeficiency viruses SIVmac251 and SIVagm by pressures of 150 and 250 MPa was determined. The extent of inactivation depended on the time that the virus was subjected to compression as well as the level of the pressure and at 150 Mpa reached 5 log1l dilution units after '10 hr. The inactivations, which were uniformly carried out at room temperature, were independent of the concentration of the virus. Possible applications of pressure inactivation for molecular biological and clinical use are discussed.The development of effective methods for eliminating unwanted or harmful components, such as viruses, present in biological samples and preparations is an important scientific endeavor with many possible practical applications. Sterilizing biological preparations and introducing new vaccines are obvious motives; moreover, all procedures that modify the biological activity of viruses can lead to a better understanding of their requirements for successful infectivity. Key considerations in practical, large-scale applications are the simplicity and reproducibility of the procedures. Physical methods are not always highly selective but they are simple, easy to reproduce, universally applicable, and relatively easy to apply on a large scale. High pressure can be applied to almost all biological preparations, is readily implemented routinely and safely in a laboratory environment, and is often selective in its action on macromolecular structures. In this report we present results showing that subjecting virus samples to pressures under 250 MPa (1 MPa = 10 atmospheres) can inactivate the simian immunodeficiency viruses SIVmac251 and SIVagm. Pressure often perturbs selectively the properties of biological molecules and complex biological systems by disrupting noncovalent associations, while leaving unaffected the covalent architecture of the separate components (1-3). This is of particular interest in prospective viral vaccines because the precise relations of the capsid proteins with each other, with the lipid membrane when there is one, and with the nucleic acids must be responsible for the specific infectivity, whereas an intact covalent framework of the proteins is necessary for the proper immune response. Hydrostatic pressures under 300 MPa can disrupt icosahedral viruses (4) and a membrane-enveloped animal virus, causing loss of infectivity with retention of the immunogenic capacity (5, 6). Therefore hydrostatic pressure procedures may by themselves, or in conjunction with other physical, chemical, or biochemical techniques, offer a suitable procedure for the preparation of vaccines. MATERIALS AND METHODSSIVmac251 was isolated from a rhesus monkey (Macaca mulatta) (7) and SIVagm Tyo 7 was isolated from an African green monkey (Cercopithecus aethiops) (8). The simian immunodeficiency viruses were grown in the CEM human T-cell line. The medium for cell growth and for virus inactivation was RPMI 1640 supplemented with 20% fetal bovine serum. The high-pressure inactivation of th...

The Metastable State of Nucleocapsids of Enveloped Viruses as Probed by High Hydrostatic Pressure

“…These results corroborate the idea that the envelope glycoproteins suffered structural modifications induced by high pressure (Fig. 6B); these changes resulted in loss of the ability to infect susceptible cells by the particles (49,54). High concentrations of urea caused complete disruption of the particles and resulted in a remarkable decrease in bis-ANS binding for both whole virus and nucleocapsids, suggesting complete unfolding of the protein components.…”

Hydrostatic Pressure Induces the Fusion-active State of Enveloped Viruses

“…2B) and could not infect cells in culture and chicken embryos. Pressure inactivation has been described for several animal enveloped viruses, such as vesicular stomatitis virus (34), simian immunodeficiency virus (35), and human immunodeficiency virus type 1 (36). Table I shows that the p 50 (pressure that promotes half of the changes in tryptophan fluorescence) did not undergo any change that is significantly above the error of the measurement when the concentration was varied for Sindbis virus, Mayaro virus, an Alphavirus, and influenza virus.…”

Disinfection of Human Tissues in Orthopedic Surgical Oncology by High Hydrostatic Pressure

“…Inactivation of numerous viruses such as herpes viruses, rotaviruses, influenza, picornaviruses as well as immunodeficiency viruses by pressure treatment has been successful in blood (45,46). The use of high pressure in decreasing virus concentration in the blood of patients suffering severe virus infections by ex vivo pressure treatment of blood has been proposed (47), but studies on HHP inactivation of viruses present in bone, cartilage or tendon have not been reported yet.…”