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

Tu.C.550 -Tu.C.560

Tuesday, July 9, 1996

to 377/1888 (20%) anrd 51/1808 (2.8%0) (p<0.001). However, with logistic regression, the
effect of thie I nterverntion vanished and a declining time trend was shown to exist. GC
declined by4.% a3rid C fby 5.I% per month (p<0.001).Although HIV- I incidence
decreased with thie tdui ation of prostitution (1 %/year of prostitution), HIV I incidence
increas ed over tiire.
Conclusions: Amonrg experienced FSWs group counselling has little additional impact on
either the prievlence of GL anrid CT cervicitis or HIV- I incidence. A general decline of bac
teria i rfections with tirne among this closed cohort suggests either acquired immunity or a
earne pro(es to avoid S-TDs However; the latter hypothesis is less likely in view of the
Inarea e of H IV I incidence over time.
Dr I phiantus Ilagi, PC) Box 19676, Nairobi, Kenya.Tel: [phone] I Fax: +254 2 7 I 2007
email: Iico N'aielkerke('akern.healthnet org
Tu.C.550
HLA CLASS I GENES AND LONG-TERM NON-PROGRESSION IN HIV INFECTION
Easterbrook Pl, Bunce M2, Sidebottom D3,Welsh K2, Dalgleish A3,Troop M1, Goodall
RL i Gizzard-B Iian G1I IChelsea & Westminster Hospital, London; 2Churchill Hospital,
Oxford; 3St. George's It ospital Medical School, London
Objectives: To exarmine' asociations between HLA class I gene products anrid both delayed
Iand riidir ItIV disease progression in a UK Caucasian population.
Methods: I68 Iong terni HIV infected individuals (median=9.5 years) were enrolled into a
study f the biological and behavioural determinants of long-term non-progression.A casecortr) ir nys;is was performed using three patient groups: non progressors (NPs) n=48;
H IV set copositi'e 8.5 year s, asymrptomatic and current CD4 count 500 cells x 106/I;
inte r rediate pro yogressors (IPs) n=69, HIV seropositive > 8.5 years, and CD4 count < 500
cells ' 06/I; and rapid progressors (RP) n=3 1, who developed AIDS within 5 years of HIV
ife ti.I \ ILAClass I molecular typing was performed using PCR-SSP Genotype frequenc ie vrre compared with Fisher's exact test and adjustment for multiple comparisons.
Results: The frequency of two Class I genotypes was significantly different between NP's
anrd RP's. The prevalenrce of HLA Cw '0602 was more frequent in NPs versus RP's (27%%
vs 8%, p 003) In contrast, the only two study participants with the rare genotype, B*4901
were anorg the II most extreme rapid progressors.
Conclusion: T 11 is is the fi st study to report on the use of Class I molecular HLA typing in
relation to IHIV disease progression. Only HLA Cw*0602 was associated with delayed dise, se prog ression. I owever, Cw'0602 is in strong linkage disequilibrium with HLA-B57, an
allele reported in association with non-progression in previous studies. No other protective
gernotypes were idenrtified, but the presence of the HLA B*490 I gene was associated with
i po i raprd diseIsr progress ion. the role of linkage disequilibrium and interaction with Class
II genei s curr ently runder investigation, ais well as the sharing of HLA amino acid positions
among te llfNPs and RPs.
Brian i vazsa id, Chelsea & Westminster Hospital, 369 Fulham Road, London SW10 9TH UK.
Il l: 01l 81816 8216; FAX: 018 I -846-6198
Tu.C.55 I
LONG-TERM ASYMPTOMATIC HIV INFECTION IN AUSTRALIA.
Ashton I, Kaldor J, Carr A2, Cunninghanm P2, Sullivan J3, Doron T3, Lloyd A4, M Kelly4,
on beh il t e- long-tern survivor study group.1 NCHECR; 2Centre for Imrmunology, St
Vincer.t's losfit., Sydney; 3NSVV Blood lransfusion Service, Clarence St. Sydney; 4Prince
Henr IHoI pit,il, Sydney
Objectives: to establish a cohort of people with long-term asymptomatic HIV infection as a
basis for diter iire n virological and immunological characteristics and identifying subtypes
of vi sin - people with long- term asyrmptomatic HIV infection in Australia.
Methods: Iridividurls were eligible for the study if they had documented HIV seropositivity
for i cas r 1ye, rs and an absence of HIV related symptomatic disease with a CD4 count
t500/m in. Blood specimens were examined for HIV isolation and quantification.Tcell subsets, p241(, I-) rmicroglobulin, HLA typing, HIV specific CTL activity, neutralising antibody
and 11 RV beta expression. Clinical status and immunological progression were monitored
at snlbsequerIt visits.
Results: Up to Nov 1995.54 study participants were recruited; 52 men and 2 women aged
between 12 and 64 years. Of participants, 89% had acquired HIV through sexual contact
and it leatft haf d been HIV antibody positive >9 years.Virus was isolated in culture from
72% of individuals and in a further 12% after CD8+ T-cell depletion.The median number of
copies of HIV RNA was 29,000/ml plasma (range <200 -250000 copies/ml) with 6 individuals reainingr P(R negative. CD4 and CD8 cell counts were not correlated with viral load.
Pr eliminar y H/A typing suggested that study participants were more likely to express the
Class I alleles B27 rand Cw2 than HIV seronegative controls.
Conclusions: the study participants appeared to be a relatively heterogenous group with a
range of plsrni viraerniia associated with levels of B2-microglobulin and p24 antigen but not
with 3 ell rtIts. Prelimirnary results also suggest that there may be an association between
HLA (lass I alleles and long -term nonprogression. However, further investigations utilising
i lechi. typing techniques will determine the role of class I and II alleles in delaying disease
pi ci.'ssio n and cor relate these ihndings with viral load and immunological assays.
LJ AsIton, t7( Victoria Street, Darlinghurst 2010 NSW Sydney Australia.Tel: [phone];
Fx: ( I 2 3i) 1837 email: hIshton@nchecr unsw.edu.au
Tu.C.552
HIV-I VIRAL LOAD IS LOW AND SLOWLY RISING IN LONG TERM SURVIVORS
WITH CD4 COUNTS LESS THAN 200/mm3
Keet Ireneus PMVeugelers PJ. Goudsmit J*, Klein M#, Miedema F, Jansen M, Coutinho RA,
de Wolf F. *Municipal Health Service, Academic Medical Centre, Department of
Retrovirology,hCental Laboratory of Bloodtransfusion#,Amsterdam,The Netherlands.
Objective: I tudv HIV I viral load in long term AIDS free survivors with CD4 counts
below 20/trnr3. '
Methods: Number of HIV i RNA copies per ml in serum was determined with Nucleic
Acid Sequence Based Amplification (NASBA) in HIV- I infected homosexual men from the
Arr i-i Iiiicohort study HIV I RNA levels in longitudinally sampled sera were analyzed
wtt "peated measurements design, using mixed model ANOVA, in HIV-t positive men
vetr AllS ee and had a drop of the CD4 count below 200/rm3. Long term AIDS

flee survivors with low C Lir counts (low CD4 LTS) were defined as individuals who
remain AIDS free acordccr to the 1987 CDC case definition during more than 5 years
after at least 2 CD4 courts, <200/mm3 within one year. In a nested case control study 10
low CD4 LTS were mtcid with 20 progressors (prog): 10 moderate prog (AIDS within I
to 3 years) arnd c0 fast pr'i (IDS within I year) after a CD4 drop below 200/mm3. Low
CD4 LTS and pro were.itlhed for age, calendar year and early treatment. HIV I RNA
levels are presented as group means after log transformation at yearly intervals, of which
year (yr) 0 is the time of the first CD4 count <200/mm3

Results: yr -2
low CD4 LTS 4.26
moderate prog 4.46
fast proy 4.51

yr -I yr0
4.02 4.34
4.75 4.81
4.90 4.94

yr I
4.45
4.94

yr 2
4.36
5.66

yr 3 yr4 yr 5
4.64 4.72 4.68 n 10
n= 10
n-- 10

HIV- I RNA levels in low CD4 LTS are lower than in moderate and fast progressors over year
2 to 0 (p-0.014), and the increase over time tends to be slower (p-0. I I). Low CD4 LTS
have lower HIV- I RNA levels than median progressors over year -2 to +2 (p=0.018). Both
low CD4 LTS and median progressors have a significant increase of load over time (p=0.008)
Conclusion: Long term survivors fr-ee of clinical AIDS with low CD4 counts are character
ized by a low and slowly increasing HIV- I viral load, as determined by serum HIV I RNA
concentration.
I.PM. Keet, Municipal Health Service, Nieuwe Achtergracht 100, 10I8 VVT Amsterdam,
Netherlands.Telephone: [phone] Fax: [phone] email: [email protected]
Tu.C.553
LONG-TERM NON-PROGRESSION IN THE SAN FRANCISCO CITY CLINIC COHORT
Buchbinder Susan P*,Vittinghoff E*, Park MS*, Elbeik T**, Kalams S*4*, Katz M*, Walker
B***, Feinberg M****. *AIDS Office, San Francisco, CA; **University of California. San
Francisco, CA; *"Massachusetts General Hospital, Boston, MA; **** Office of AIDS
Research, Bethesda, MD, USA
Objective: To identify and characterize long-term non-progressors from the San Francisco
City Clinic Cohort (SFCC) by immunologic and virologic parameters.
Methods: Progression to AIDS (1993 CDC case definition) was determined by KaplanMeier analysis for men from SFCC with well-defined dates of HIV seroconversion (SC).
Nonprogressors (NP) were defined as men without AIDS with CD4>500 at their most
recent visit > 10 years after SC arid were compared to recent seroconverters (RSC) who
were infected I-7 years and also maintained CD4>500. NP were compared with RSC by
CD4 counts and slopes, CD8 counts, standard lymphocyte culture, plasma viral copy number by bDNA assay, and cytotoxic lymphocyte assay (CTL).
Results: Of 623 men from the SFCC with known SC, an estimated 2 1% will remain AIDSfree 15 years after SC (95% CI 18-25%). NP were 5% of the 590 men with follow-up > 10
years after SC and were HIV-infected a median of 14. I years. Compared with RSC with
similar CD4 counts (676 vs. 66 I/mm3), NP had more stable CD4 slopes (-9 vs. -36
cells/year, p<0.05), and higher CD8 counts (1022 vs. 877/mm3, p<0.0 I). NP were significantly less likely to have a positive PBMC culture on all visits (86% vs. 98%, p<0.05)
although all but one NP and all RSC had positive cultures on at least one visit. NP were
more likely than RSC to have a viral load < 10,000 copies/rm3 (62% vs. 18%, p-0.04). Of
6 NP tested, all had CTL detected on stimulated assay and had CTL clones identified and 4
were positive on CTL bulk assay against 2-4 different HIV I gene products; 5 of these 6 had
persistently low viral burden (<10,000) on 4-8 occasions tested. None of 4 RSC tested had
CTL on bulk assay and none had viral loads persistently < 10,000.
Conclusions: A srnall proportion of men with long-term infection are nonprogressors with
stable CD4 counts, high CD8 counts, and persistently low viral load compared to men with
similarly high CD4 counts with recent HIV infection. Nonprogressors are nevertheless a
heterogeneous group; in addition, a subset with broadly reactive CTL have persistently low
viral load, suggesting that CTL may play a role in control of viral replication.
SP Buchbinder, AIDS Office, 25 Van Ness Ave., #500, San Francisco, CA 94102, USA
Telephone: [phone], Fax: [phone], e-mail: [email protected]
Tu.C.560
HIV/AIDS IN CANADIAN WOMEN: INJECTION DRUG USE AN
INCREASING CONCERN
Lior LeeY*, Archibald C*,Yan P*, Blanchard J**, Larke B***, Dawood M****, Senzilet L*,
Hockine J*****, Sutherland D*. *Bureau of HIV/AIDS & STD, Health Canada; **Dept of Health,
Mantoba;***Alberta Healthu;** **Cadham Prov Lab, Manitoba;*****LCDC, Health Canada
Objective: To describe the trends in risks for HIV/AIDS in Canadian women.
Methods: Estimates of cumulative HIV infections were calculated using data fiom provincial
databases, recent seroprevalence studies and population surveys. Recent antenatal studies
were used to estimate infection rates among women of childbearing age. AIDS data were
derived from the Canadian AIDS Case Reporting and Surveillance System, a national database which collects AIDS case reports from each province and territory Data for other
countries were extracted from the literature.
Results: As of September 30, 1995, 12 119 AIDS cases had been reported in Canada.
Adjusting for reporting delay and under reporting gives an estimate of about 18 000 cases.
Of the reported cases, 686 were in women over age 15, a cumulative incidence of 6.5/100
000.The proportion of AIDS cases attributed to women was 5.6% during 198 -1989; 5.4%
during 1990-1992 and 6.4% during 1993-1995. For all cases, the distribution by risk category of reported femnale AIDS cases was: heterosexual contact - 37.5%; origin in a pattern II
country - 26.1%; injection drug use (IDU) - 15%; blood/blood products - 14% and no iden
tified risk factor - 7%. Of these, IDU has shown the most dramatic increase: IDUs accounted for 6.8% of adult female AIDS cases in the period 1981-1989, 17% during 1990 -1992
and 23% during 1993-1995. With respect to cumulative HIV infections, we estimate that by
the end of 1993, about 4 200 women had been infected in Canada; 90% of these infections
were in women aged 15-44. Recent antenatal studies in several Canadian provinces show
seroprevalence rates ranging from one to nine per 10 000.Where studies have been
repeated, there is evidence of stable or increasing trends. In the province of Manitoba. ante
natal seroprevalence rose from 0.72/10 000 in 1990-1991 to 3.2/10 000 in 1994 1995.The
trend of increasing infections among women is also seen in other developed countries.

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