Simian immunodeficiency virus

Last updated
Simian immunodeficiency virus
SIV virion in 3D.jpg
SIV virion model obtained with cryo-electron microscopy scanning
Virus classification OOjs UI icon edit-ltr.svg
(unranked): Virus
Realm: Riboviria
Kingdom: Pararnavirae
Phylum: Artverviricota
Class: Revtraviricetes
Order: Ortervirales
Family: Retroviridae
Genus: Lentivirus
Species:
Simian immunodeficiency virus

Simian immunodeficiency virus (SIV) is a species of retrovirus that cause persistent infections in at least 45 species of non-human primates. [1] [2] Based on analysis of strains found in four species of monkeys from Bioko Island, which was isolated from the mainland by rising sea levels about 11,000 years ago, it has been concluded that SIV has been present in monkeys and apes for at least 32,000 years, and probably much longer. [3] [4]

Contents

Virus strains from three of these primate species, SIVsmm in sooty mangabeys, SIVgor in gorillas and SIVcpz in chimpanzees, are believed to have crossed the species barrier into humans, resulting in HIV-2 and HIV-1 respectively, the two HIV viruses. The most likely route of transmission of HIV-1 to humans involves contact with the blood of chimps and gorillas that are often hunted for bushmeat in Africa. Four subtypes of HIV-1 (M, N, O, and P) likely arose through four separate transmissions of SIV to humans, and the resulting HIV-1 group M strain most commonly infects people worldwide. [5] [6] Therefore, it is theorized that SIV may have previously crossed the species barrier into human hosts multiple times throughout history, but it was not until recently, after the advent of modern transportation and global commuterism, that it finally took hold, spreading beyond localized decimations of a few individuals or single small tribal populations.

Unlike HIV-1 and HIV-2 infections in humans, SIV infections in their natural simian non-human hosts appear in many cases to be non-pathogenic due to evolutionary adaptation of the hosts to the virus. Extensive studies in sooty mangabeys have established that SIVsmm infection does not cause any disease in these primates, despite high levels of circulating virus. Regulation of the activity CCR5 coreceptor is one of the natural strategies to avoid disease in some natural host species of SIV. [7]

Unlike SIVsmm infection in sooty mangabeys, a recent[ when? ] study of SIVcpz in wild living chimpanzees suggests that infected chimpanzees experience an AIDS-like illness similar to HIV-1 infected humans. The later stages of SIV infection develop into sAIDS, much like how HIV infection develops into AIDS.

Taxonomy

The simian (monkey-hosted) immunodeficiency viruses are a species of retrovirus in the Primate group of genus Lentivirus along with the human viruses HIV-1 and HIV-2 that cause AIDS, and a few other viruses that infect other primates. Related viruses in other groups in the genus infect other mammals like sheep and goats, horses, cattle, cats and a few others. The genus is one of 6 genera in subfamily orthoretrovirinae which together with genus Spumavirus form family retroviridae of all RNA retroviruses (RNA viruses which use a DNA intermediate). [8]

The ICTVdB code of SIV is 61.0.6.5.003. [9] Although HIV-1 and HIV-2 cladistically fall into SIV, [10] ICTV considers them distinct species from ordinary, non-human-infecting SIV.

Strains

 grp i 
 
 
 
 

HIV-1

 

cpzPtt

 

gor

 

cpzPts

 
 
 

drl

 

mnd2

 
 

rcm

 

agi

 grp ii 
 
 
 

HIV-2

 

mac

 

mne

 

stm

 

smm

 grp iii/agm 
 
 
 

gri

 

ver

 

tan

 

sab

 grp iv 
 
 
 

lho

 

sun

 

prg

 

mnd1

 
 
 

wrc

 

olc

 
 

trc

 

krc

 grp v 
 
 
 
 
 
 

gsn

 

mus2

 (grp vi) 
 
 
 

col

 

kcol1

 

kcol2

blc

 

mon

 

mus1

reg

 
 

tal

 
 

asc

 

bkm

 
 

deb

blu

 
 
 

den

 

syk

 

wol

Phylogenetic relations between simian immunodeficiency viruses (SIVs) [10] [11] [12] [13] [14]

While human immunodeficiency virus has a limited number of subtypes, SIV is now known to infect a few dozen species of non-human primates, and distinct strains are often associated with each species, or with a set of closely related species. The thus far categorized ~40 strains are divided into 5 distinct groups and one subgroup: [10]

In addition to the subgroups defined for extent SIVs, two endogenous SIVs are found in prosimian lemurs. These paleo-SIVs form a basal branch relative to extant SIVs. [15]

History

Immunodeficiency resembling human AIDS was reported in captive monkeys in the United States beginning in 1983. [16] [17] [18] SIV was isolated in 1985 from some of these animals, captive rhesus macaques suffering from simian AIDS (SAIDS). [17] The discovery of SIV was made shortly after HIV-1 had been isolated as the cause of AIDS and led to the discovery of HIV-2 strains in West Africa. HIV-2 was more similar to the then-known SIV strains than to HIV-1, suggesting for the first time the simian origin of HIV. Further studies indicated that HIV-2 is derived from the SIVsmm strain found in sooty mangabeys, whereas HIV-1, the predominant virus found in humans, is derived from SIV strains infecting chimpanzees (SIVcpz).[ citation needed ]

Chimpanzees are not believed to be the original hosts of an independent lineage of SIV, but rather that SIVcpz is a relatively recent acquisition resulting from a recombination of SIVgsn (greater spot-nosed monkeys) and SIVrcm (red-capped mangabeys) within the host chimpanzee. It is known that chimpanzees hunt and consume these monkeys for food. [19] In 2010, researchers reported that SIV had infected monkeys in Bioko for at least 32,000 years. Based on molecular clock analyses of sequences, it was previously thought by many that SIV infection in monkeys had happened over the past few hundred years. [20] Scientists estimated that it would take a similar amount of time before humans would adapt naturally to HIV infection in the way monkeys in Africa have adapted to SIV and not suffer any harm from the infection. [21]

In 2008, discovery of an endogenous lentivirus in a prosimian (proto-monkey) primate, the gray mouse lemur native to Madagascar, pushed the origin of SIV-like lentivirus infections in primates back to at least 14 Ma, the last time there was intermingling of mammals between the island of Madagascar and the African mainland, if the infection is attributed to horizontal transmission between homologous hosts. If the virus and host were coevolved, rather than acquired, that potentially pushes the date of the endogenous event back to approx. 85 Ma, the split between the lemur-like and monkey-like primate lineages. That date barely antedates the emergence of the primates 87.7 Ma. [22]

Virology

Structure and genome

The SIV virion is a spherical to pleomorphic glycoprotein envelope 110-120 nm enclosing a 110x50nm truncated cone or wedge-shaped (occasionally rod) capsid containing a dimeric pair of positive-sense single-stranded RNA genome.[ citation needed ]

Genome

  • coding regions

Proteome

  • genes: env, gag, pol, tat, rev, nef, vpr, vif, vpu/vpx
  • Structural proteins (envelope): SU, TM,(gag): MA, CA, NC
  • Enzymes: RT, PR, IN
  • Gene regulators: Tat, Rev
  • Accessory proteins: Nef, Vpr, Vpx, Vif

Tropism

Differences in species specificity of SIV and related retroviruses may be partly explained by variants of the protein TRIM5α in humans and non-human primate species. This intracellular protein recognizes the capsid of various retroviruses and blocks their reproduction. Other proteins such as APOBEC3G/3F that exerts antiretroviral immune activity, may also be important in restricting cross-species transmission. [23]

Replication

 +ssRNA → -ssDNA → dsDNA → +ssRNA (viral genome)                          → +ssmRNA → viral protein
  • integration
  • latency
  • cleavage
  • protein synthesis
  • Assembly

Quasispecies

The speed and transcription inaccuracies of RNA viruses give rise to antigenically distinct varieties in a single host animal. These quasispecies do not necessarily give rise to population-wide new organisms. The rate of proliferation of quasispecies has significant implication for host immune control, and therefore virulence of the organism.[ citation needed ]

Pathogenesis

About 100,000 cells from rhesus macaques, grouped by similarity. Red cells are from monkeys infected with simian-human immunodeficiency virus, while blue cells are from uninfected ones. Mapping SHIV infection in the body, 2018 - Wellcome Photography Prize 2019 (bottom right, cropped).jpg
About 100,000 cells from rhesus macaques, grouped by similarity. Red cells are from monkeys infected with simian-human immunodeficiency virus, while blue cells are from uninfected ones.

SIV pathogenesis encompasses both pathogenic and non-pathogenic SIV infections. SIV infection of non-human primates (NHPs) invariably results in persistent infection, but rarely acute disease. Pathogenic infection is typified by Rhesus macaques infected with SIV strains derived from sooty mangabeys. Disease progression to AIDS occurs within a period of months to years, depending upon the SIV strain used. Non-pathogenic infection is typified by African NHPs naturally infected with SIV. These animals rarely progress to AIDS despite maintaining viral loads that are equivalent to SIV viral loads in pathogenic infections. It is postulated that AIDS-like disease in African NHPs represents horizontal transmission of the virus from one or more homologous species in the recent evolutionary past, before equilibrium of co-adaptation has occurred.[ citation needed ]

SIV/HIV infection similarities and differences

The similarities of the two types of virus infections: [24]

The differences (what happens in nonhuman primates):

Epidemiology

strainlineagehostbinomialdisease
HIV-1SIVcpzhumansH. sapiens AIDS
HIV-2SIVsmmhumansH. sapiens AIDS
SIVcpzSIVrcm/SIVgsnChimpanzeeP. TroglodytesSAIDS
SIVgorSIVcpzGorillaG. gorilla( - )
SIVsmmSooty mangabey( - )

Beatrice Hahn of the University of Pennsylvania and a team of researchers in 2009 found that chimpanzees do die from simian AIDS in the wild and that the AIDS outbreak in Africa has contributed to the decline of chimpanzee populations. Testing wild chimpanzees, researchers detected organ and tissue damage similar to late-stage human AIDS. The infected chimpanzees had a 10 to 16 times greater risk of dying than uninfected ones; infected females were less likely to give birth, could pass the virus to their infants, and had a higher infant mortality rate than uninfected females. [25] [26] Bonobos appear to avoid simian immunodeficiency virus (SIV) and its effects, though it is not known why. [19]

African green monkeys (also called vervets, genus Chlorocebus) in African populations are heavily infected with SIVagm, [27] [28] while the virus is absent in the founder isolate vervet populations in the Caribbean. [29] The prevalence of SIV infection in African populations ranges 78-90% in adult females and 36-57% in adult males, while SIV infection is rare in immature individuals. [28] [27] SIV infected vervets in the wild do not develop chronic immune activation or microbial translocation (assessed by sCD14 as a surrogate biomarker). During natural SIV infection, the gut microbiome showed a significant increase in microbial diversity, a decrease in Proteobacteria/Succinivibrio and an increase of Veillonella, and a decrease in genes involved in pathways of microbial invasion, and partial reversibility of acute infection-related shifts in microbial abundance. [30] The pattern of natural selection in the monkey genome in genes involved in HIV responses and those regulated in response to experimental SIV infection in monkeys, but not macaques, suggests a natural adaptation to SIV in Chlorocebus monkeys in Africa. [31]

Vaccine research

In 2012, researchers reported that initial infection of rhesus monkeys by neutralization-resistant SIV strains [32] could be partially prevented through use of an anti-SIVSME543 vaccine obligately including Env protein antigens. [33]

In 2013, a study by a group of authors reported on successful testing of a vaccine containing SIV protein-expressing rhesus cytomegalovirus vector. Approximately 50% of vaccinated rhesus macaques manifested durable, aviraemic control of infection with the highly pathogenic strain SIVmac239. [34]

See also

Related Research Articles

<span class="mw-page-title-main">HIV</span> Human retrovirus, cause of AIDS

The human immunodeficiency viruses (HIV) are two species of Lentivirus that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.

<span class="mw-page-title-main">Bushmeat</span> Meat hunted in tropical forests

Bushmeat is meat from wildlife species that are hunted for human consumption. Bushmeat represents a primary source of animal protein and a cash-earning commodity for inhabitants of humid tropical forest regions in Africa, Latin America and Asia. Bushmeat is an important food resource in poor, rural communities.

The oral polio vaccine (OPV) AIDS hypothesis is a now-discredited hypothesis that the AIDS pandemic originated from live polio vaccines prepared in chimpanzee tissue cultures, accidentally contaminated with simian immunodeficiency virus and then administered to up to one million Africans between 1957 and 1960 in experimental mass vaccination campaigns.

<span class="mw-page-title-main">TRIM5alpha</span>

Tripartite motif-containing protein 5 also known as RING finger protein 88 is a protein that in humans is encoded by the TRIM5 gene. The alpha isoform of this protein, TRIM5α, is a retrovirus restriction factor, which mediates a species-specific early block to retrovirus infection.

<i>Chlorocebus</i> Genus of Old World monkeys

Chlorocebus is a genus of medium-sized primates from the family of Old World monkeys. Six species are currently recognized, although some people classify them all as a single species with numerous subspecies. Either way, they make up the entirety of the genus Chlorocebus.

<span class="mw-page-title-main">Sooty mangabey</span> Species of mammal

The sooty mangabey is an Old World monkey found in forests from Senegal in a margin along the coast down to the Ivory Coast.

<span class="mw-page-title-main">History of HIV/AIDS</span> Epidemiological history

AIDS is caused by a human immunodeficiency virus (HIV), which originated in non-human primates in Central and West Africa. While various sub-groups of the virus acquired human infectivity at different times, the present pandemic had its origins in the emergence of one specific strain – HIV-1 subgroup M – in Léopoldville in the Belgian Congo in the 1920s.

Simian foamy virus (SFV) is a species of the genus Spumavirus that belongs to the family of Retroviridae. It has been identified in a wide variety of primates, including prosimians, New World and Old World monkeys, as well as apes, and each species has been shown to harbor a unique (species-specific) strain of SFV, including African green monkeys, baboons, macaques, and chimpanzees. As it is related to the more well-known retrovirus human immunodeficiency virus (HIV), its discovery in primates has led to some speculation that HIV may have been spread to the human species in Africa through contact with blood from apes, monkeys, and other primates, most likely through bushmeat-hunting practices.

HIV/AIDS was recognised as a novel illness in the early 1980s. An AIDS case is classified as "early" if the death occurred before 5 June 1981, when the AIDS epidemic was formally recognized by medical professionals in the United States.

HIV superinfection is a condition in which a person with an established human immunodeficiency virus infection acquires a second strain of HIV, often of a different subtype. These can form a recombinant strain that co-exists with the strain from the initial infection, as well from reinfection with a new virus strain, and may cause more rapid disease progression or carry multiple resistances to certain HIV medications.

<span class="mw-page-title-main">CXCR6</span>

C-X-C chemokine receptor type 6 is a protein that in humans is encoded by the CXCR6 gene. CXCR6 has also recently been designated CD186.

<span class="mw-page-title-main">Subtypes of HIV</span> Variants of the human immunodeficiency virus

The subtypes of HIV include two main subtypes, known as HIV type 1 (HIV-1) and HIV type 2 (HIV-2). These subtypes have distinct genetic differences and are associated with different epidemiological patterns and clinical characteristics.

<span class="mw-page-title-main">Agile mangabey</span> Species of Old World monkey

The agile mangabey is an Old World monkey of the white-eyelid mangabey group found in swampy forests of Central Africa in Equatorial Guinea, Cameroon, Gabon, Central African Republic, Republic of Congo, and DR Congo. Until 1978, it was considered a subspecies of the Tana River mangabey. More recently, the golden-bellied mangabey has been considered a separate species instead of a subspecies of the agile mangabey.

<span class="mw-page-title-main">Central chimpanzee</span> Subspecies of ape

The central chimpanzee or the tschego is a subspecies of chimpanzee closely related to the other great apes such as gorillas, orangutans, and humans. The central chimpanzee can be found in Central Africa, mostly in Gabon, Cameroon, Republic of Congo and the Democratic Republic of Congo.

<span class="mw-page-title-main">Nef (protein)</span>

Nef is a small 27-35 kDa myristoylated protein encoded by primate lentiviruses. These include Human Immunodeficiency Viruses and Simian Immunodeficiency Virus (SIV). Nef localizes primarily to the cytoplasm but also partially to the Plasma membrane (PM) and is one of many pathogen-expressed proteins, known as virulence factors, which function to manipulate the host's cellular machinery and thus allow infection, survival or replication of the pathogen. Nef stands for "Negative Factor" and although it is often considered indispensable for HIV-1 replication, in infected hosts the viral protein markedly elevates viral titers.

<span class="mw-page-title-main">Janice E. Clements</span> American biologist, academic and medical researcher

Janice Ellen Clements is vice dean for faculty at the Johns Hopkins School of Medicine and the Mary Wallace Stanton Professor of Faculty Affairs. She is a professor in the departments of Molecular and Comparative Pathobiology, Neurology, and Pathology, and has a joint appointment in molecular biology and genetics. Her molecular biology and virology research examines lentiviruses and how they cause neurological diseases.

Mason-Pfizer monkey virus (M-PMV), formerly Simian retrovirus (SRV), is a species of retroviruses that usually infect and cause a fatal immune deficiency in Asian macaques. The ssRNA virus appears sporadically in mammary carcinoma of captive macaques at breeding facilities which expected as the natural host, but the prevalence of this virus in feral macaques remains unknown. M-PMV was transmitted naturally by virus-containing body fluids, via biting, scratching, grooming, and fighting. Cross contaminated instruments or equipment (fomite) can also spread this virus among animals.

Beatrice H. Hahn is an American virologist and biomedical researcher best known for work which established that HIV, the virus causing AIDS, began as a virus passed from apes to humans. She is a professor of Medicine and Microbiology in the Perelman School of Medicine at the University of Pennsylvania. In November 2002, Discover magazine listed Hahn as one of the 50 most important women scientists.

<span class="mw-page-title-main">Host switch</span> Evolutionary change of the host specificity of a parasite or pathogen

In parasitology and epidemiology, a host switch is an evolutionary change of the host specificity of a parasite or pathogen. For example, the human immunodeficiency virus used to infect and circulate in non-human primates in West-central Africa, but switched to humans in the early 20th century.

Theodora Hatziioannou is a Greek-American virologist. She known for her work discovering restriction factors that counteract HIV-AIDS and other primate lentiviruses, thus restricting them to specific species, and making it hard to study HIV-1 in animals. Her findings allowed her to develop the first HIV-1-based virus which is capable of recapitulating AIDS-like symptoms in a non-hominid. She is a Research Associate Professor in the Laboratory of Retrovirology at The Rockefeller University in New York. She is a co-author of a textbook on virology, Principles of Virology.

References

  1. Peeters M, Courgnaud V, Abela B (2001). "Genetic Diversity of Lentiviruses in Non-Human Primates" (PDF). AIDS Reviews. 3: 3–10. Retrieved 2020-07-11.
  2. Peeters M, Courgnaud V (2002). Kuiken C, Foley B, Freed E, Hahn B, Korber B, Marx PA, McCutchan FE, Mellors JW, Wolinsky S (eds.). Overview of Primate Lentiviruses and their Evolution in Non-human Primates in Africa (PDF). HIV sequence compendium. Los Alamos, NM: Theoretical Biology and Biophysics Group, Los Alamos National Laboratory. pp. 2–23. Retrieved 2010-09-19.
  3. McNeil Jr DG (September 16, 2010). "Precursor to H.I.V. Was in Monkeys for Millennia". New York Times . Retrieved 2010-09-17. In a discovery that sheds new light on the history of AIDS, scientists have found evidence that the ancestor to the virus that causes the disease has been in monkeys and apes for at least 32,000 years — not just a few hundred years, as had been previously thought. ... That means humans have presumably been exposed many times to S.I.V., the simian immunodeficiency virus, because people have been hunting monkeys for millenniums, risking infection every time they butcher one for food.
  4. Worobey M, Telfer P, Souquière S, Hunter M, Coleman CA, Metzger MJ, et al. (September 2010). "Island biogeography reveals the deep history of SIV". Science. 329 (5998): 1487. Bibcode:2010Sci...329.1487W. doi:10.1126/science.1193550. PMID   20847261. S2CID   37803712..
  5. Sharp PM, Hahn BH (August 2010). "The evolution of HIV-1 and the origin of AIDS". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 365 (1552): 2487–2494. doi:10.1098/rstb.2010.0031. PMC   2935100 . PMID   20643738.
  6. Peeters M, D'Arc M, Delaporte E (2014). "Origin and diversity of human retroviruses". AIDS Reviews. 16 (1): 23–34. PMC   4289907 . PMID   24584106.
  7. Jasinska AJ, Pandrea I, Apetrei C (2022-01-27). "CCR5 as a Coreceptor for Human Immunodeficiency Virus and Simian Immunodeficiency Viruses: A Prototypic Love-Hate Affair". Frontiers in Immunology. 13: 835994. doi: 10.3389/fimmu.2022.835994 . ISSN   1664-3224. PMC   8829453 . PMID   35154162.
  8. "Taxon Details | ICTV". ictv.global.
  9. ICTV database entry: 61.0.6.5.003
  10. 1 2 3 Sharp PM, Hahn BH (September 2011). "Origins of HIV and the AIDS pandemic". Cold Spring Harbor Perspectives in Medicine. 1 (1): a006841. doi:10.1101/cshperspect.a006841. PMC   3234451 . PMID   22229120.
  11. Ahuka-Mundeke S, Ayouba A, Mbala-Kingebeni P, Liegeois F, Esteban A, Lunguya-Metila O, et al. (December 2011). "Novel multiplexed HIV/simian immunodeficiency virus antibody detection assay". Emerging Infectious Diseases. 17 (12): 2277–2286. doi:10.3201/eid1712.110783. PMC   3311211 . PMID   22172157.
  12. Pancino G, Silvestri G, Fowke KR (2012). Models of Protection Against HIV/SIV: Avoiding AIDS in Humans and Monkeys. Elsevier. p. 6. ISBN   978-0-12-387715-4.
  13. Peeters M, Courgnaud V, Abela B, Auzel P, Pourrut X, Bibollet-Ruche F, et al. (May 2002). "Risk to human health from a plethora of simian immunodeficiency viruses in primate bushmeat". Emerging Infectious Diseases. 8 (5): 451–457. doi:10.3201/eid0805.010522. PMC   2732488 . PMID   11996677.
  14. Lauck M, Switzer WM, Sibley SD, Hyeroba D, Tumukunde A, Weny G, et al. (October 2013). "Discovery and full genome characterization of two highly divergent simian immunodeficiency viruses infecting black-and-white colobus monkeys (Colobus guereza) in Kibale National Park, Uganda". Retrovirology. 10: 107. doi:10.1186/1742-4690-10-107. PMC   4016034 . PMID   24139306.
  15. Gilbert, C; Maxfield, DG; Goodman, SM; Feschotte, C (March 2009). "Parallel germline infiltration of a lentivirus in two Malagasy lemurs". PLOS Genetics. 5 (3): e1000425. doi: 10.1371/journal.pgen.1000425 . PMC   2651035 . PMID   19300488.
  16. Letvin NL, Eaton KA, Aldrich WR, Sehgal PK, Blake BJ, Schlossman SF, et al. (May 1983). "Acquired immunodeficiency syndrome in a colony of macaque monkeys". Proceedings of the National Academy of Sciences of the United States of America. 80 (9): 2718–2722. Bibcode:1983PNAS...80.2718L. doi: 10.1073/pnas.80.9.2718 . PMC   393899 . PMID   6221343.
  17. 1 2 Daniel MD, Letvin NL, King NW, Kannagi M, Sehgal PK, Hunt RD, et al. (June 1985). "Isolation of T-cell tropic HTLV-III-like retrovirus from macaques". Science. 228 (4704): 1201–1204. Bibcode:1985Sci...228.1201D. doi:10.1126/science.3159089. PMID   3159089.
  18. King NW, Hunt RD, Letvin NL (December 1983). "Histopathologic changes in macaques with an acquired immunodeficiency syndrome (AIDS)". The American Journal of Pathology. 113 (3): 382–388. PMC   1916356 . PMID   6316791.
  19. 1 2 Sharp PM, Shaw GM, Hahn BH (April 2005). "Simian immunodeficiency virus infection of chimpanzees". Journal of Virology. 79 (7): 3891–3902. doi:10.1128/JVI.79.7.3891-3902.2005. PMC   1061584 . PMID   15767392.
  20. McNeil Jr DG (17 September 2010). "Precursor to H.I.V. Was in Monkeys for Millenniums". The New York Times. Retrieved 17 September 2010.
  21. "HIV precursor in monkeys ancient: study". CBC News. 17 September 2010. Archived from the original on March 25, 2013. Retrieved 17 September 2010.
  22. Gifford, RJ; Katzourakis, A; Tristem, M; Pybus, OG; Winters, M; Shafer, RW (23 December 2008). "A transitional endogenous lentivirus from the genome of a basal primate and implications for lentivirus evolution". Proceedings of the National Academy of Sciences of the United States of America. 105 (51): 20362–7. doi: 10.1073/pnas.0807873105 . PMC   2603253 . PMID   19075221.
  23. Heeney JL, Dalgleish AG, Weiss RA (July 2006). "Origins of HIV and the evolution of resistance to AIDS". Science. 313 (5786): 462–466. Bibcode:2006Sci...313..462H. doi:10.1126/science.1123016. PMID   16873637. S2CID   27673160.
  24. Pandrea, Ivona; Sodora, Donald L.; Silvestri, Guido; Apetrei, Cristian (September 2008). "Into the Wild: Simian Immunodeficiency Virus (SIV) Infection in Natural Hosts". Trends in Immunology. 29 (9): 419–428. doi:10.1016/j.it.2008.05.004. ISSN   1471-4906. PMC   2840226 . PMID   18676179.
  25. Chimpanzees Do Die From Simian AIDS, Study Finds by Lawrence K. Altman Chimpanzees Do Die from Simian AIDS, Study Finds
  26. Keele BF, Jones JH, Terio KA, Estes JD, Rudicell RS, Wilson ML, et al. (July 2009). "Increased mortality and AIDS-like immunopathology in wild chimpanzees infected with SIVcpz". Nature. 460 (7254): 515–519. Bibcode:2009Natur.460..515K. doi:10.1038/nature08200. PMC   2872475 . PMID   19626114.
  27. 1 2 Ma D, Jasinska A, Kristoff J, Grobler JP, Turner T, Jung Y, et al. (January 2013). "SIVagm infection in wild African green monkeys from South Africa: epidemiology, natural history, and evolutionary considerations". PLOS Pathogens. 9 (1): e1003011. doi:10.1371/journal.ppat.1003011. PMC   3547836 . PMID   23349627.
  28. 1 2 Ma D, Jasinska AJ, Feyertag F, Wijewardana V, Kristoff J, He T, et al. (May 2014). "Factors associated with siman immunodeficiency virus transmission in a natural African nonhuman primate host in the wild". Journal of Virology. 88 (10): 5687–5705. doi:10.1128/JVI.03606-13. PMC   4019088 . PMID   24623416.
  29. Kapusinszky B, Mulvaney U, Jasinska AJ, Deng X, Freimer N, Delwart E (August 2015). "Local Virus Extinctions following a Host Population Bottleneck". Journal of Virology. 89 (16): 8152–8161. doi: 10.1128/jvi.00671-15 . PMC   4524239 . PMID   26018153.
  30. Jasinska AJ, Dong TS, Lagishetty V, Katzka W, Jacobs JP, Schmitt CA, et al. (November 2020). "Shifts in microbial diversity, composition, and functionality in the gut and genital microbiome during a natural SIV infection in vervet monkeys". Microbiome. 8 (1): 154. doi: 10.1186/s40168-020-00928-4 . PMC   7648414 . PMID   33158452.
  31. Svardal H, Jasinska AJ, Apetrei C, Coppola G, Huang Y, Schmitt CA, et al. (December 2017). "Ancient hybridization and strong adaptation to viruses across African vervet monkey populations". Nature Genetics. 49 (12): 1705–1713. doi:10.1038/ng.3980. PMC   5709169 . PMID   29083404.
  32. "Neutralization-resistant" refers to strains which are not able to be neutralized by the native immune response due to compensating mutation; see HIV-1 related information.
  33. Barouch DH, Liu J, Li H, Maxfield LF, Abbink P, Lynch DM, et al. (January 2012). "Vaccine protection against acquisition of neutralization-resistant SIV challenges in rhesus monkeys". Nature. 482 (7383): 89–93. Bibcode:2012Natur.482...89B. doi:10.1038/nature10766. PMC   3271177 . PMID   22217938.
  34. Hansen SG, Piatak M, Ventura AB, Hughes CM, Gilbride RM, Ford JC, et al. (October 2013). "Immune clearance of highly pathogenic SIV infection". Nature. 502 (7469): 100–104. Bibcode:2013Natur.502..100H. doi:10.1038/nature12519. PMC   3849456 . PMID   24025770.

Further reading