Oral Abstract Session 01 - Global HIV Vaccine Enterprise

Topic 5: HIV Transmission and Viral Diversity
P05.15
Genetic Characterization of HIV-1 Subtype G
Envelope Sequences by Single Genome Analysis
E. Rene Ghislain 1 , M. Tongo 2 , E. Ngolle 3 , W. Burgers 2 , J. Dorfman 1
1 International Centre for Genetic Engineering and
Biotechnology, Cape Town, South Africa; 2 Division of Medical
Virology, University of Cape Town, Cape Town, South
Africa; 3 Centre de Recherche en Maladies Emergentes et
Reemergente (CREMER), Yaounde, Cameroon
Background: Subtype G is the sixth most prevalent subtype of
HIV-1 and is responsible for an estimated 1,500,000 infections
worldwide. Although systematic analyses of a wide range of HIV-
1 envelope sequences and neutralization have been performed,
subtype G viruses are severely underrepresented in these
studies. There is thus an important need to study subtype G
envelope sequences and their neutralization capacities.
Methods: 64 Plasma samples from Cameroon were used and
6 were found to be Subtype G by sequencing of gag and nef
including one typed only for gag. Single genome analysis (SGA)-
PCR was then performed and full length envelope genes were
generated, which were then sequenced in the V1-V5 region
Results: Phylogenetic analysis of V1-V5 envelope sequences
confirmed that 5 samples grouped within the expected subtype
G and 1 with subtype A which we had been unable to type for
nef. Sequences from within one sample were genetically related
to each other, while samples were genetically distinct from each
other. This suggests that the sequenced HIV-1 from any donor
were generally from a single infection. Sequences from 4 of 5
samples grouped most closely to other West African subtype
G sequences, while the fifth grouped in a cluster populated by
sequences from Spain and few other African sequences. The V1-
V5 region of the sixth sample clustered with subtype A and is
thus presumed to be a recombinant.
Conclusion: These results suggests that our samples capture a
substantial amount of the diversity within the subtype G envelope
sequences and are largely different from each other. Therefore,
forthcoming data concerning the neutralization patterns of these
viruses will be able to give some of the sense of the diversity of
neutralization pattern of subtype G viruses that will be needed to
design a truly global vaccine.
P05.16
AIDS Vaccine 2012
Posters
Enrolment and Logistical Challenges in TaMoVac 01
Phase I/II HIV Trial Despite the Completion of an
Earlier (HIVIS-03 trial trial) in Dar es Salaam
M. Ngatoluwa 1 , P. Munseri 1 , M. Janabi 1 , F. Mhalu 1 ,
E. Sandstrom 2 , M. Bakari 1
1 Muhimbili University of Health and Allied Sciences, United
Republic of Tanzania; 2 Karolinska Institutet, Sweden
Background: Participation of sub-Saharan countries in HIV
vaccine trials is important in the fight against HIV/AIDS, and has
to be sustained by continued trials. Experiences from earlier
trials are expected to influence the design and the performance
of subsequent trials. Following completion of HIVIS-03 trial,
TaMoVac- 01 trial was initiated. We compare enrolment
experiences between the two trials.
Methods: The HIVIS-03 trial, conducted between 2007 - 2010
recruited 60 volunteers from the Police force in Dar es Salaam.
The subsequent TaMoVac- 01 trial has recruited 62 volunteers
from the Police and Prisons force, and youths at IDC.
Results: Enrollment of volunteers into the HIVIS-03 took 12
months while the TaMoVac-01 trial took 13 months.
Screened: enrolled ratio was 3:1for HIVIS-03 trail, while for
TaMoVac-01 8:1. Reasons for screen-out in the TaMoVac-01 trial
were influence of family, misconception, clinical and laboratory
abnormalities.
Recruitment of females was a challenge in the HIVIS-03 trial, but
was unnoticed in the TMV-01 trial, this could be due to inclusion
of youths. Misconceptions in the Police force remain an obstacle
to recruitment despite regular education sessions.
Other challenges were: Poor adherence to schedules, due
to competing prioritization of employment requirements;
difficulties in communication with volunteers without phones.
Most challenges were addressed through collaboration with the
concerned authorities in the respective cohorts
Conclusion: Recruitment challenges continued in the TMV-
01 trial despite our experiences with HIVIS-03 trial. Enhanced
Community engagement and timely action by the researchers is
necessary to ensure a smooth conduct of the trials.
171
POSTERS