Abstracts Vol. 1 [International Conference on AIDS (11th: 1996: Vancouver, Canada)]

Monday, July 8, 1996

Mo.A.392 - Mo.A.400

ed less than 7 years and had CD4 counts >500. In vivo activated (II -ctivity in fresh
unstimulated PBMC, CTL precursor frequency, and proliferative C,t'on:," to intact HIV- I
envelope and gag proteins were measured. In addition, CTL clone s isolted fri omr several
subjects were subjected to T cell receptor (TCR) analysis.
Results: In a previously published study we found evidence of circulir, i Ectivated, HIV- Ispecific CTL in 4/5 LTNP with extremely low viral loads (<500 pe'c, of viral RNA/ml) and
low levels of detectable neutralizing antibodies (Harrer et. al., AIDS yP. t rlm. Retroviruses
(1996), in press). In follow-up studies an additional subject nfe i t nr, sr,'t I years and
with undetectable plasma HIV- I RNA has high levels of activatI CTI, and aiiother previously studied subject has shown stable CTL activity over a 3 yLr i:e i trid. ius far three
subjects with low viral loads have demonstrated high levels of cellular pri)eration (stimulation indices as high as 176) in response to whole HIV- I proteist Cqa, iFn r ivE). In one subject with low viral load the TCR genes of 2 distinct CTL clone oi on iepitope specificity
were sequenced. Functional precursor fiequencies of CTL directed,ginst these epitopes
are 1/4000 and I / 12,000 respectively. However, the frequency ofT P tricnsiripts from
clones with these epitope specificities in PBMC is much higher, I 1 and 1/555 respectively.
Conclusions: The detection of in vivo activated CTL in these L>IiP with extremely low
viral loads implies active imunoregulation by the cellular arm of the immune response in
these individuals. Our preliminary studies analyzing TCR transciipt fequen,,, imply that epitope-specific CTL undergo significant expansions in these subject. Additicna' studies will
help determine whether the presence of circulating CTL or HIV- I proliferative responses
are independent predictors of non-progression. If so, efforts to augment these cellular
immune responses in infected persons would be warranted.
Spyros A. Kalams, M.D. MGH-East, 149 13th Street, Room 5217 Chariestown, MA 02129, USA.
Phone [phone] Fax [phone]
Mo.A.392
CHARACTERIZATION OF A POLYCLONAL CYTOLYTIC T LYMPHOCYTE
RESPONSE TO HUMAN IMMUNODEFICIENCY VIRUS IN INDIVIDUALS WITHOUT
CLINICAL PROGRESSION
Lubaki, Michel N*, Dhruva By, Quinn TC*,/*, Siliciano RF*, Bollingcr fRC~.Johns Hopkins
University, Baltimore, Maryland; * National Institutes of Allergy and Infectious Diseases,
National Institutes of Health, Bethesda, Maryland
Objective: To characteize a detailed clonal analysis of the cytolytic F lyphocyte (CTL)
response to HIV-I in two individuals who have been infected with I l V- I for greater than
10 years and have maintained an absolute CD4 counts of greater thf in 801 cells/mm3.
Methods: HIV- I-specific CTL activity was measured in fresh and stircui,ted PBMC from 2
HIV- I-infected patients without evidence for clinical progression, usingi scWidard51Crrelease assay PBMC were stimulated in an antigen-specific mannier sng in soralen-treated,
UV irradiated autologous B lymphoblastoid cells infected with vaccircia expressing HIV- I
genes. CTL clones were isolated and characterized from stimult, HPBMg.
Results: A total of 67 HIV- I -specific ICTL clones were isolated freom se subjects. Evidence
fora sdiverse, polyclonal HIV- I-specific CTL response was found in both subjects. HIV-I-specific Ct. clones fom both patients utilized multiple HLA class I all Ic aeGenetic analysis of
tlw -F cell receptor gene usage by multiple B62-estricted, HIV-I ag-specific CTL clones isolated from a single blood sample feiom one subject revealed th e utili zation of four different
V(3 genes In addition, using an in vitro antigen-specific stimulation cithod, multiple CTL
clones could be isolated from the same time-point directed against HIV- I gag, nef and env.
Characterization of the peptide epitope specificity in a subset of these cones revealed the
recognition of gag and nef peptides derived from highly conserved regions of HIV-lI. Finally,
a longitudinal analysis of CTL specificity resulted in the isolation of i TI_ clones directed
against multiple HIV- I antigens, including the isolation of CTL clones directed gainst the
same highly conserved nef peptide over a I year period, despite no detectable circulating
viral plasma RNA.
Conclusions: These data suggest that in some individuals without clinr-a Fpogression and
low levels of circulating HIV- I virus, the CTL response is polyclonai, directedi against multiple
HIVI proteins, including highly conserved peptides within these proteins, and is maintained
over time.
Michel N. Lubaki, Johns Hopkins University Ross Research Building R-oom ri 1159, 720
Rutland Avenue, Baltimore, MD 21205,Tel:[phone] Fax: [phone],
Email: NLUBAKI(IWEL.CHLINK.WELCH.JHU.EDU
Mo.A.393
IMMUNOLOGICAL STUDIES ON THE FRENCH COHORT OF 70 HIV- I-INFECTED
LONG-TERM NON PROGRESSORS (LTNP)
ad ii. F I Bonduelle O1, Candotti D,Bouley jM, CostaglolID t I. Roczioux C2,
Goubar A>, Clauvel JP2, Sicarid D2, Autran B. 'lLab. Ir /-uno!, CNR',I p. Pitic--
Salpdtriere, 2ALF Study Group, Paris, France.
Objective:To study the immunological parameters associated to r'e L I cLi'ttus with special regards for the CD4 + T helper cell reactivity to FIIV.
Methods: A cohort of 70 LTNP was recruited in 1994 n the, in. infection fr
at 8 yers, positive oi 01 CD4T cell slope for the last ars e 00 m,no etrovi
cal theiapy, comparecd to controls with the sarre duration of infitiction as 1(c[14 counts
between 300,ind 400/m3. We studied 11D4-h cell activti, -oi i-S i, in-r't r icogens, soluble antigens and HIV ant'gens, Th I rnd Th2 cots okine prcauctoci Fl
and antiviril CD18 cl fun cion in relationship to viral lotd0
Results: Up to eo 31 patients were studied: 2 sub groups wei e ind tiuhzed upon city of CD4 ciui ts at 6 months after inclusion: LTNP- 118 subje, a. CD.I=70Smrn3
[278-1210]): LNP 2!0 subjects, (mean CD4=463/mm3 [2785 h]. These - sub-groups
did not differ for,ge 'sex ratio and risk group. CD4+ cell activation ws hiher in LTNP- I
than LTNP-2 reardin CD2 I.fCD71, HLA-DR, arid acsociated wih hie cllular virem'a
though non significa-nt, if ntly lower CD28 expression wa, -ser ved in [!NP-I than in
LTNP 2 that might assess for progression of immune defects. 1-h cell piroliferative
responses were equvalent in the 2 groups, with sub-normal respors: to CD3 +/ CD28
or +/!L 2, PWM or soluble antigens, no defect in Th i c'tokirn (iiL2 - ii IFN,) but lower
IL 4 p roduct, in group LTNP I. A CD4 F cell reactivity io HIV! r,,.,-,d p23 was
observed in 3 out of 7 LTNP tested, while no reactivity for gp 0 ar.," contrasted with
conserved pioliferatrori to CandidinTuberculin in 4 cases; no cona -_n was indu:ed by

addition of IL-2 or by increasing CD4+ responder cell numbers. A strong HIV-specific CTL
reactivity was detectable independently of the subgroup. Anti-HIV CD8 suppressive activity
will be presented in relationship to viral load and CTL reactivity.
Conclusion:This L.NTP cohort was found to be heterogeneous regarding the CD4 1 cell
count providing opportunity to analyze I) HIV-specific CD4+ T helper cells in relationship
with a conserved ThI cell function and 2) mechanisms initiating CD4+ T cell anergy in
HIV disease.
F. Hadida, Laboratoire D'Immunologie Cellulaire URACNRS 625, 83, BId De L'Hopital, B^t.
Cervi 75013 ParisTel (33 1) 42. 17.75. II Fax (33 I) 42 17 74 90
Mo.A.394
HIV PENOTYPE AND INTERLEUKIN-2/INTERLEUKIN-10 RATIO ARE ASSOCIATED
MARKERS OF PROTECTION AND PROGRESSION IN HIV INFECTION
Clerici, Marieo, Balotta C**, Salvaggio A***, Riva C**,Trabattoni D*, Papagno L**,
Berlusconi A**, Rusconi S**,Villa ML*, Moroni M**, Galli M**. *Cattedra di Immunologia
and ** Istituto di Igiene e Medicina Preventiva, Universita' Milano, 20100, Milano; -"Clinica
Malattie Infettive, H. L. Sacco, 20157, Milano, Italy
Objective: To establish possible correlations between virologic and immunologic markers of
protection and progression in HIV infected individuals.
Methods: We cross-sectionally analysed the rate and extent of HIV replication; HIV phenotype; in vitro-stimulated cytokine production [interferon gamma and interleukin-2 (type I
cytokines) as well as IL-4 and IL- I0 (type 2 cytokines)]; CD4 counts: and beta-2 m concentration in 63 consecutively enrolled HIV-seropositive individuals.
Results: We observed that the virologic and immunologic markers of HIV infection are
tightly correlated. According to the results of Kruskal-Wallis tests, important differences
between the individuals classified according to HIV positivity isolation of HIV and identification of SI variants were observed for all immunologic variables with the exception of beta
2m. Also, a relationship between the severity of the virologic status in HIV-seropositive individuals, as inferred by the isolation of the virus, and the presence of SI variants, was evident
for all immunologic variables, again with the exception of beta 2m.Thus, lack or low prevalence of HIV isolability and the presence of non-syncitium inducing strains of HIV are associated with the strongest type I cytokine production, the weakest type 2 cytokine production, and highest CD4 counts. Conversely, the isolation of highly replicating, syncitium-inducing HIV strains is associated with the weakest type I cytokine production, the strongest
type 2 cytokine production, and lowest CD4 counts. Additionally, it was determined that the
IL-2/IL- 10 ratio best discriminates amongst HIV-seropositive individuals with different virologic profiles, and who are likely to have different prognosis. Finally we identified a significant
inverse relationship between CD4 count and ratio of type 2 to type I cytokines.
Conclusions: The virologic and immunologic correlates of disease protection and progression are closely associated variables that define two different subsets of HIV-seropositive
individuals.These data strongly support the viroimmunonologic hypothesis of HIV infection.
Supported by grants from Istituto Superiore di Sanita'"VII/VIII Progetto AIDS 1994/95".
Mario Clerici, MD, Cattedra di Immunologia, University degli Studi di Milano, Via Venezian, 1,
20133 Milano, ITALY. Phone: [phone]; FAX: [phone].
e-mail: bmago imiucca.csi.unimi.it.
Mo.A.395
MICROSATELLITE POLYMORPHISMS OF THE HUMAN TNF LOCUS ARE ASSOCIATED WITH THE RATE OF HIV DISEASE PROGRESSION
Khoo lSHI, Pepper L3, Snowdon N4, Wilkins EGL5,Valleley p2, OllierW3 [I] Department
of Pharmacology & Therapeutics, University of Liverpool, PO Box 147, Liverpool, UK; [2]
Departments ofVirology and [3] ARC, Medical School, Manchester University, UK; [4]
Department of Immunology Hope Hospital, Manchester, UK; [5] epartment of Infectious
Diseases, North Manchester General Hospital, Manchester; UK;
Background: The rate of immunological deterioration and progression to AIDS differs
markedly between HIV-positive individuals, and may be influenced by cofactors, THIV phenotype and the host-cell response. Production ofTNFo stimulates viral replication and may
accelerate progression and CD4 depletion. MHC polymorphism may therefore account for
some of the observed differences in rate of disease progression.
Methods: We examined HLA class II,TAP2 andTNF microsatellite polymorphisms in 30
HIV+ patients with slower disease progression (CD4 count >400/rmm3 at 7 years since
first positive HIV-antibody test) and 22 with rapid progression (CD4 count -200/mm3
within 5 years of last negative HIV-antibody test). HLA DRB I and DQA alleles were
defined using sequence-specific oligotyping and IAP2 polymorphisms by ARMS-PCR.Typing
of TNF, A, B, C and D microsateihites was performed. Allele frequencies were compared
with a natch ed panel of HIV-netative controls (n-177). All subjects and control were
Caucasian and resident in NW England.
Results: No relationship with DR3 orTAP2 frequencies was observed. DQBt1*0302 was
ignificantly decreased with faster compared to slower progressors (0% vs 55.6%: OR 21.2,
95% (I 2.3-1961). Possession of theTNF C2. allele in fist vs slow was 6.3% vs 68.8% (OR
1303 95'a CI 0.00-0.29).
Conclusions: OAr results cuggest that MHC polymorphsms, particularly surruodng the
maiF qocus. exert a powerful influence upon the rate of progression of HIV infection, particuleth irn h m w ndbjesh with rcapidly parogressive diseuase.
STye Khoo Depairtent of P1armacology &herapeutics, Uriversity of Liverpool
P0 Box 147, Liverpool LIKe: (+) 44 IS5I 794 5553
Mo.A.400
SIV-SUPERINFECTION IMMUNITY IN MACAQUES IS INFLUENCED BY THE DOSE
OF ATTENUATED VIRUS
SbarpeSally A, Whatmore AM, Cook N1, Poly-anskauya Nm, Hall U* Rud F*, Stott FJ '-*,
Cnraage lPl. - CAMR, Salisbury, UK *Laboratory Geratre for Disease Control, Ottawa,
Garsada; - 1NIBSC, Potters Bar, UK.
Objective: To determeine if the dose of live attenuated SIVmac used to "immcunise"
macaquec influernces the outcome of subsecqcent challernge with virulent, nuon--clonal vius.
Methods: Ten rhesus macaques wer-e inoculated with the SlVmauc molecuhar clone 118,
whfich hacs an attenuated phenrotype sir wivo due to a I12bp in-frarrie deletuoa in the nef/I 3'
LIP region. Five pairs of aranmals were each inoculated intravenously with au single dilution of

<10
0
nO
ct_
U
o
C
C
0
at
C
ci
I)
c0
nO
Q)
Q.)
0
nc0
at
c
12