{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T15:03:48Z","timestamp":1781103828385,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"8","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1991,4,15]]},"abstract":"<jats:p>Two human immunodeficiency virus (HIV)-seropositive chimpanzees (A-3 and A-86c) infected 4 yr earlier with HIV, along with one uninfected animal (A-36), were inoculated intramuscularly three times in a year with a gamma-irradiated gp120-depleted HIV immunogen in incomplete Freund's adjuvant. Both previously infected animals promptly developed an anamnestic humoral antibody response after the first dose, and the uninfected animal developed a primary humoral response to the first dose and then an anamnestic response to the second dose. Although HIV had been recovered repeatedly from the seropositive animals, they became persistently virus-culture negative at the time of or just before the first inoculation of the immunogen. Intravenous challenge with 40 chimpanzee-infectious-doses of a heterologous HIV strain (HIVIIIB) was done 4 mo after the third inoculation in the three treated chimpanzees and in an untreated control animal (A-189a). The immunized naive animal (A-36) and the unimmunized control (A-189a) became infected, and virus has been isolated from their peripheral blood mononuclear cells for greater than 2 yr after challenge. However, the two previously infected chimpanzees (A-3 and A-86c) resisted challenge and have remained virus negative by peripheral blood mononuclear cell cocultivation for greater than 2 yr of observation after challenge; moreover, no evidence of reinfection was detectable by PCR. Despite the in vivo resistance, however, peripheral blood mononuclear cells from the resistant animals (A-3, A-86c) remained susceptible to infection by HIV in vitro. These findings reveal that a state of immunity can develop and\/or be induced to control and\/or prevent HIV infection in the chimpanzees. In the absence of any detectable level of neutralizing antibody in A-3 and a low level in A-86c, the patterns of the responses to challenge seen in the four animals suggest that the cell-mediated immune mechanism must have played a significant role in the resistant chimpanzees both in control of their HIV infection and in their resistance to challenge.<\/jats:p>","DOI":"10.1073\/pnas.88.8.3348","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T07:57:47Z","timestamp":1149062267000},"page":"3348-3352","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":25,"title":["Observations after human immunodeficiency virus immunization and challenge of human immunodeficiency virus seropositive and seronegative chimpanzees."],"prefix":"10.1073","volume":"88","author":[{"suffix":"Jr","given":"C J","family":"Gibbs","sequence":"first","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Peters","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M","family":"Gravell","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B K","family":"Johnson","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"F C","family":"Jensen","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D J","family":"Carlo","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Salk","sequence":"additional","affiliation":[{"name":"Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1991,4,15]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.88.8.3348","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T13:10:01Z","timestamp":1649855401000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.88.8.3348"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1991,4,15]]},"references-count":0,"journal-issue":{"issue":"8","published-print":{"date-parts":[[1991,4,15]]}},"alternative-id":["10.1073\/pnas.88.8.3348"],"URL":"https:\/\/doi.org\/10.1073\/pnas.88.8.3348","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1991,4,15]]},"assertion":[{"value":"1991-04-15","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}