Report of
the First Brazilian Symposium on Basic Research in HIV/ AIDS
Vol. 91(3):
329-334
Angra dos Reis,
RJ, Brazil
September 13 - 16,
1995
Bernardo Galvão-Castro,
Luiz Roberto Ribeiro Castelo Branco, Mariza Gonçalves Morgado*,
Vera Bongertz*
Laboratório
Avançado de Saúde Pública, Centro de Pesquisa Gonçalo
Moniz - FIOCRUZ, Salvador, BA, Brasil *Departamento de Imunologia, Instituto
Oswaldo Cruz, Av. Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brasil
During the first
decade of AIDS epidemic in Brazil very little basic research on HIV-1
was performed in this country. In fact, the efforts of Brazilian scientists
and the government policy were aimed to solve the immediate health problems
created by the emergent HIV-1/AIDS epidemic. The First Brazilian Symposium
on Basic Research in HIV/AIDS was held in Angra dos Reis, Rio de Janeiro,
from 13 to 16 of September 1995, in order to disseminate scientific
information and enhance national and international collaboration with
a view of strengthening national research capabilities.
Opportunity was
taken to posthumously honor Dr Marguerite (Peggy) Pereira and Dr Helio
Gelli Pereira, two of the world's most distinguished virologists, whose
life-work was presented by Dr Herman Schatzmayr (FIOCRUZ, Rio de Janeiro).
These scientists contributed a great deal to solve some severe and important
public health problems in Brazil. Thanks to their contributions it has
been possible to achieve significant success in controlling the HIV/AIDS
epidemic spread in blood donation centers in Brazil.
Dr Bernardo Galvão-Castro
(FIOCRUZ, Salvador) summarized the main historical aspects of the AIDS
epidemic in Brazil. He recalled that the first AIDS cases reported in
Brazil date back from 1982, when six cases were reported in São
Paulo and Rio de Janeiro. At that time, there was no official program
to face this emergent epidemic. In fact, this program was established
in 1985. Recognizing the severity of this new public health problem,
some groups of Brazilian researchers, mainly in São Paulo and
Rio de Janeiro, iniciated some activities in clinic, immunology and
epidemiology of HIV/AIDS.
In July 1985 Drs
Peggy and Helio Pereira kindly donated H9/HIV-1 infected cells to the
Oswaldo Cruz Foundation. This enabled FIOCRUZ to promptly set up the
HIV-1 screening routine in the public Brazilian blood bank network,
using the immunofluorescence assay. The first isolation of HIV-1 from
a seropositive Brazilian individual was achieved in May 1987. During
this time, a lot of effort was oriented towards solving emergent public
health needs such as the development of easy, quick and cheap screening
and confirmatory assays for the serological diagnosis. The importance
of several institutions in financing reasearch projects, e.g. Fundação
Banco do Brasil, National Research Council (CNPq) and Petrobrás
was pointed out.
Representing the
Ministry of Health, Dr Euclides A Castilho highlighted the trends of
the HIV/AIDS epidemic in Brazil. He stated that in the beginning of
the epidemic, the epidemiologic profile was similar to that observed
in the USA and Western Europe. The homosexual/bisexual mode of transmission
was the most important route in the propagation of infection in Brazil.
Later, the epidemic profile began to change and currently the intravenous
drug use and the heterosexual mode of transmission have assumed greater
significance. He also summarized the present prevalence of HIV/AIDS
in Brazil: as of February of 1995, a total of 71,111 AIDS cases were
officially reported to the Ministry of Health. The infection is disseminated
all over the country and the estimated prevalence of infection in terms
of incidence per 100,000 inhabitants is 11.2 in the Northern, 13.0 in
the Northeastern, 32.3 in the Middle-Western, 91.0 in the Southeastern
and 26.5 in the Southern regions of Brazil. With respect to sexual preferences,
since 1980 a total of 45% of the cases of HIV/AIDS occurred in homosexual/bisexual
men and 17.7% in heterosexuals. The parenteral mode of transmission
accounts for 25.2% of cases due to blood or blood factors and 21% due
to intravenous drug use.
Dr Eduardo Martins,
Vice-President of the FIOCRUZ, drew attention to the fact that the Oswaldo
Cruz Foundation, as the main research institution of the Ministry of
Health, recognizes the urgent need to establish ways to face the HIV-1
epidemic in Brazil as well as other emergent or re-emergent infections.
Therefore, the Institutional Program of AIDS was set up as a pilot program
in 1991, in order to obtain more skill, knowledge and efficacy in the
control of this devastating epidemic. The program involves multidisciplinar
activities in the areas of basic, clinical, epidemiological and educational
research.
Dr Herbert de Souza,
President of the Brazilian Interdisciplinary AIDS Society (ABIA) called
attention to a very important aspect of the HIV-1 epidemic in Brazil:
the dissemination to the low-income population. This fact will have
very important implications in the overall control of HIV/AIDS in Brazil.
Taking this in consideration, he stated that it is extremely urgent
to strengthen and amplify the public health services. He also emphasized
the importance of the integration of basic research with clinical and
social activities to control this infection. Finally, he reaffirmed
that the society has great confidence, expectations and hope in the
joint efforts of the scientists to surmount this epidemic.
Anti-HIV/AIDS Vaccines
A review on the
actual stage of development and evaluation of anti-HIV/AIDS vaccine
candidates worldwide was presented by Dr S Osmanov of the Vaccine
Development Unit of the Global Programme on AIDS of the World Health
Organization. Relevant information presented included the tendency of
the transformation from an AIDS epidemy to a worldwide disease, with
a frightening increase of actual and predicted infection rates for mainly
Asia and Africa but also for Latin America. The extreme genotypic variety
of HIV in different geographical areas was discussed, as well as the
shift in predominant genotypes. The necessity of the establishment of
a correlation between genotypic characteristics of the viral variants
with the immune response of the infected individuals (serotyping, analysis
of functional HIV neutralizing antibodies) for choice of vaccine candidates
in different geographical areas, as well as the study of the importance
of factors affecting natural resistance and long-term non-progression
was pointed out. A rapid review of anti-HIV/AIDS vaccine candidates
was presented, stressing the promising results obtained with the use
of live vectors followed by booster immunizations with proteins or peptides.
The need for more detailed studies aiming to answer critical questions
still to be solved, such as the necessity of obtaining heterotypic immune
responses, the importance of inducing not only systemic but local protection,
most importantly at mucosal levels, the lack of data concerning the
influence of secondary and opportunistic infections, such as other sexually
transmitted diseases, the need to protect not only adults but also children
against HIV infection or at least the associated disease, among questions
related to risk/benefit analyses which have to be considered before
entering into studies related to the vaccination strategies (phase IV),
predicted to start as late as 2005.
The results obtained
by the WHO Network for HIV isolation and characterization, established
in order to answer some of the questions presented above, were outlined
by Dr J Mullins (University of Washington, Seattle). The study aimed
to analyse the variability of HIV in different geographical regions
and to establish the importance of HIV variation at the level of the
hosts immune response induced. Results obtained up to now indicate the
low correlation between genotypic and serotypic analyses and the lack
of correlation between genotypes and the kinds of HIV neutralizing antibodies
induced. However, interesting new data has been established by phenetic
analysis (B Korber), indicating that although the V3 loop of the gp120
envelope glycoprotein cannot be defined as the linear "principal
neutralization domain" any more, the conformation of the V3 loop,
as affected by charged amino acids, does correlate with the biological
characteristics of the HIV variant in question. As positive correlation
between biological characteristics (cytopathogenic effect) and disease
progression has been established, the data indicating that conformation
of the V3 loop (as predicted by genetic analysis) can be associated
to prognosis of HIV infection.
Dr CV Hanson (CA
Dept Health Services, Bethesda) presented data on the HIVNET established
in the USA for evaluation of anti-HIV/AIDS vaccine studies, indicating
the protocol for phase I/II trials followed in the USA, stressing the
high number of volunteers needed for meaningful analyses in low incidence
areas. The particular efforts of the CA Dept of Health Services on analysis
of the HIV neutralizing antibody response of vaccinated individuals,
using different assays and quantifying analyses were presented, including
the preliminary results obtained which indicate a lack of widerange
neutralizing antibody response against different HIV variants detected
in the vaccinees.
An interesting pre-clinical
trial was described by JG Guillet (I Pasteur, Paris), in which specific
cytotoxic T lymphocytes could be induced by immunization of mice and
of macacques with HIV-1 peptides (env, nef, gag) coupled to a lipidic
tail. A trial in human volunteers is being initiated.
Gene Therapy
A review of recent
progress in gene therapy anti-HIV/AIDS was presented (O Ferreira, UCLA,
Los Angeles), discussing strategies employing HIV-1 specific ribozymes,
antisense RNA, RNA decoys and expression of mutant HIV genes with dominant
repressor activity. Particularly experiments related to this last approach,
using the necessity of HIV-1 for the human t-RNA/Lys3 for reverse transcription,
were presented. Results of in vitro experiments indicate that
susceptibility to HIV-1 infection can be reverted by transduction of
a lymphocytic cell line with a mutant tRNA (tRNAtarD).
Dr F De Lucca (USP,
Ribeirão Preto) presented interesting results about the in
vitro transfer of cellular immunity to human lymphocytes with exogenous
RNA obtained from mice immunized with synthetic peptides corresponding
to immunologically important HIV-1 epitopes, and discussed the potential
use of this methodology for immunotherapy.
Mucosal Immunity
Prof GE Griffin
(University of London) described how HIV infects mucosal tissues. He
showed results of in vitro studies of infection of human mucosal
tissue - gut and cervix explants - by HIV, demonstrating that gut and
cervical immune cells are potential targets for direct HIV infection.
His studies on nutrition have demonstrated that the majority of patients
within the initial phases of AIDS can gain weight and that weight loss
is associated with lower food intake and not with energy loss as hypothesized.
The human gastrointestinal
immune responses to HIV was discussed and results of studies done in
Europe and Africa were shown, which suggest that the mucosal system
is able to respond well to oral immunogens until relatively late in
HIV disease (LRR Castello-Branco, FIOCRUZ/Banco do Brasil, Rio de Janeiro).
Immunopathology
The alterations
found in lymph nodes of HIV-1 positive patients were described (D Paiva,
UERJ, Rio de Janeiro). Her studies, using histological methods and immunocytochemistry,
showed that during progression of HIV disease to AIDS different patterns
of abnormalities were seen, from an initial follicular hyperplasia to
a subsequent follicular involution.
HIV neutralization
The importance of
HIV neutralizing antibodies in pathogenesis, transmission and protection
studies was discussed by Dr EM Fenyö (Karolinska Institute, Stockholm).
Recent data indicating the positive correlation between neutralizing
antibodies and slower disease progression was established by analysis
of primary HIV infection, analysing sequential HIV isolates. Studies
of vertical HIV transmission established significant correlation between
range of HIV neutralization and lower risk of HIV transmission from
mother to child (G Scarlatti et al.). Similar results were found in
a study of heterosexual HIV transmission. Attempts to associate genetic
subtypes with "neutralization serotypes" have not been successful,
although neutralization subtypes appear to exist.
Description of the
cryptic nature of envelope gp120 V3 loop neutralizing epitopes in primary
monocytotropic HIV-1 was given by Dr DC Bou-Habib (FDA, NIH, Bethesda).
Studies carried out using a novel CD4+ T-cell line (PM-1) permissive
for both monocytotropic and T-cell-tropic virus types permitted a comparative
analysis of neutralization of two viral variants with rabbit antiserum
to a recombinant of the monocytotropic variant gp120 and anti-V3 monoclonal
antibodies. The resistance of the primary monocytotropic variant to
these antibodies contrasted with the susceptibility of the T-cell-tropic
variant maintained in T-cell line cultures.
Results on studies
of neutralizing antibodies in Brazil were presented, indicating that
both in São Paulo (LFM Brígido, Adolfo Lutz Institute,
São Paulo) and in Rio de Janeiro (V Bongertz, FIOCRUZ, Rio de
Janeiro) the presence of neutralizing antibodies active against autologous
and heterologous HIV-1 variants isolated from individuals residing in
Brazil could be detected, with results comparable to those obtained
in other parts of the world. Data indicating a reverse correlation between
50% neutralization susceptibility of Brazilian primary HIV-1 isolates
and lack of potency of the corresponding antisera in neutralizing heterologous
primary isolates were presented.
Cytotoxic T lymphocytes
Protective response
against HIV has been correlated to neutralizing antibodies and cytotoxic
T lymphocytes (CTL), therefore these immune responses are attempted
to be induced by anti-HIV/AIDS vaccine candidates. The difficulties
in inducing autologous neutralizing antibodies, the decreasing response
of autologous neutralizing antibodies with progression of disease and
data indicating a loss of Th1 response with disease progression have
focused interest in the cellular response against HIV-1. Studies with
peptides derived from env, gag and nef regions of HIV-1 have indicated
not only induction of specific CTL but also a positive correlation between
CTL response and reduction of viral load as well as a slowing down of
disease progression (JG Guillet).
The high frequency
detection of CD45RO precursor CTL for HIV-1 Nef protein in unexposed
human blood donors was presented by Dr MA Lucchiari-Hartz (Butantan
Institute, São Paulo). The generation and characterization of
Nef-specific cytotoxic T cell responses of most tested non-infected
subjects through in vitro stimulation with autologous EBV-transformed
lymphoblastoid B cell lines expressing Nef-protein was described. These
CTLs were characterised as CD3+ CD4- CD8+ and MHC class I restricted
cells. Both CD45RO and CD45RA were able to generate Nef-specific and
EBV-specific CTL responses, with a higher frequency in the CD45RO subset.
HIV-1 polymorphism
A study of the molecular
variability of HIV-1 and its implication on cell tropism and pathogenicity
was presented by Dr C Cheng-Mayer (Aaron Diamond AIDS Research Center,
New York). The importance of the stage of the disease for virus isolation
and characterization, of the amino acid sequence, charge and quaternary
conformation of the envelope gp120 V3 loop in phenotypic characteristics
of the HIV-1 isolate was discussed. Results of comparative studies of
the T-cell-line adapted, syncytium inducing HIV-1 SF2 isolate and the
monocytotropic, non-syncytium inducing HIV-1 isolate SF162 were presented,
comparing the V3 loop amino acid sequences and their susceptibility
to neutralizing monoclonal antibodies and to the inhibitory effect of
soluble CD4. The importance of studying biological characteristics of
HIV-1 isolates with polymeric envelope gp120 in contrast to monomeric
recombinant gp120 analyses was pointed out.
An extensive evaluation
of HIV diversity in Brazil was presented in this meeting by the group
of Brazilian researchers participating in the National Network on HIV
Isolation and Characterization. Using the heteroduplex mobility assay
to define HIV-1 subtypes of isolated viruses or of peripheral mononuclear
cells from HIV-1infected individuals. Dr E Sabino (Adolpho Lutz Institute,
São Paulo) showed the presence of the B and F subtypes among
intravenous drug users in São Paulo, suggesting that the frequency
of F subtype is higher in this group. Using the same methodology, Dr
PC Ferreira (UFMG) evaluated 18 samples obtained from blood donors and
hemophiliac patients in Belo Horizonte, MG. While all hemophiliac patients
(8) were infected with subtype B, 2 out of the 10 blood donors analyzed
were infected with subtype F. Similarly, Dr MG Morgado (FIOCRUZ, Rio
de Janeiro) also showed the presence of the B and F HIV-1 subtypes in
Rio the Janeiro. Although her data are suggestive of an increase of
the frequency of the F subtype, no association between subtype distribution
and sex or risk group could be established. Results were also presented
of the lymphoproliferative response of HIV-1 infected individuals to
15mer synthetic peptides corresponding to the crown of the V3 loop .
Despite inter-isolate peptide sequence heterogeneity, HIV-1 positive
individuals reactive to the typical Brazilian HIV-1 B peptide (GWGR)
had broad lymphoproliferative reaction with other peptides such as the
MN, LAI, SF-2 or B consensus (GPGR), suggesting conservative T cell
epitopes in the region covered by those peptides (MG Morgado, FIOCRUZ,
Rio de Janeiro). Using another approach, based on the restriction fragment
length polymorphism of the PCR amplified protease gene, Dr A Tanure
(UFRJ, Rio de Janeiro) showed dual infections with distinct HIV-1 subtypes
in HIV positive individual from Rio de Janeiro. Indeed, infection with
HIV-1 B and F subtypes was detected in one individual, with subtypes
F and D in another and with subtypes C and D in a couple and, possibly,
their child. These data suggest that infection with one HIV-1 subtype
does not protect against superinfection with other subtypes.
One of the points
discussed was the effort to establish serotypes of HIV-1 and the attempts
to correlate serotypes and genotypes. The data obtained by the WHO Network
for HIV Isolation and Characterization indicate that there is no absolute
correlation between genotypes and serotypes of HIV-1, although it was
possible to separate A/C genotypes as one serotype (94%), genotype E
as another serotype (93%) and B and B' as a distinct serotype (80%),
although relatively extensive cross-reactivity could be established
between genotypes (J Mullins). An assay able to differentiate between
the North-American/European B genotype and the B' genotype detected
in Brazil was presented, employing biotinilated peptides, indicating
that the specific affinity of anti-B' antibodies to B' peptides could
be used for a positive serotyping assay (CV Hanson).
Disease progression
markers and diagnosis
Dr RS Pereira (University
of London) discussed some results from studies carried out in England
on immunological markers for HIV progression. He pointed out that CD4
T cell count, measured by flow cytometry, is still the best investigation
test. As this test is expensive, a suggestion was made that clinicians
should use this tool to follow decrease of CD4 count, avoiding tests
when CD4 count is below 50/µl as the number seldomly increases
thereafter.
The cellular immune
responses in HIV infected subjects and the mechanisms that cause depletion
of CD4+ cells during HIV infection were discussed by Dr A Duarte (USP,
São Paulo). He pointed out that while CD4 T cells decrease in
number, the expression of CD4 molecules on the surface of these cells
increases. He presented results on immunological markers during infection
showing increase of IgG in serum, decrease of delayed-type hypersensitivity
and dysfunction of helper T cell responses.
The hypothesis that
there is a switch from the Th1 cytokine profile to Th0/Th2 during evolution
to AIDS was discussed (LS Camargo, USP, São Paulo). This switch
is important in inducing eosinophilia, increase of serum IgE and IgA,
CD4 T cell decrease, increase of side effects to drugs and decrease
of delayed-type hypersensitivity.
A new diagnostic
PCR HIV test to be used on dried blood spots on filter paper was presented
(S Cassol, British Columbian Center for Excellence in HIV/AIDS, Vancouver).
This test presents high sensitivity (94.7%) and specificity (100%).
When used in newborn children, the sensitivity on days 0 to 4 is 27%,
increasing on days 10 to 15 (89%) and reaching its maximum (100%) from
day 16 onwards.
The usefulness of
detection of anti-reverse transcriptase antibodies (RTI) in HIV-1 infection
as a progression marker was discussed by Dr M Ueda (Adolfo Lutz Institute,
São Paulo). Results on detection of RTI in 80 to 90% (n=20) asymptomatic
HIV-1 infected individuals and sequential follow-up of RTI titers indicated
a significant decrease in RTI titers in correlation to disease progression.
Correlation of the decrease in RTI titers with increase in beta-2-microglobulin
detection in individuals with fast disease progression was statistically
significant. A study of 54 asymptomatic males (homosexual transmission
of HIV-1) indicated an inverse correlation between viral load and RTI
titers.
Results of analyses
of children of HIV-1 infected mothers obtained with antibody detection,
p24 determination, HIV-1 isolation and PCR detection of proviral DNA
in 44 children were presented (JP Simonetti, FIOCRUZ, Rio de Janeiro).
Co-Infections
One of the most
important aspects discussed in this Symposium concerned the immunopathological
features of co-infections between HIV-1 and other infectious diseases
endemic in Brazil.
In this context,
tuberculosis represents one of the most frequent diseases associated
to HIV infection in Brazil and its diagnosis, depending on the patient,
can be predictive of HIV infection. In this meeting, John Ho (Cornell
University, New York) discussed the hyphotesis that co-infections accentuate
the intrinsic immunopathology of HIV infection, shortening the HIV disease
free interval and survival. Moreover, he also provided evidence that
co-infections with sexually transmitted diseases can enhance HIV replication
and transmission. Co-infections might enhance HIV replication by direct
or indirect mechanisms or, alternativelly, co-infections might result
in immune activation, suppression or immune cell depletion that would
affect HIV replication or contribute to immunessuppression.
The immunopathological
aspects of the association between HIV infection and tuberculosis were
studied in a phenotyping analysis of cell populations from the bronchoalveolar
lavage and from the peripheral blood obtained from AIDS patients and
those co-infected with Mtb, as well as their functional activity determined
(MG Bonecini-Almeida, FIOCRUZ, Rio de Janeiro/Cornell University, New
York). Low lymphoproliferative response to PPD and Mtb antigens was
verified for the cells from the bronchoalveolar lavage in the co-infected
HIV/Mtb individuals, in addition to the reduced phagocytic activity
of monocytes/macrophages and neutrophils. She also showed the expression
of inducible nitric oxide synthase in human macrophages as well as its
envolvment in the anti- Mtb activity of human macrophages.
In another attempt
to understand the mechanisms envolved in the hosts defense against Mtb,
Dr JR Lapa e Silva (FIOCRUZ-UFRJ, Rio de Janeiro) evaluated the phenotype
of the mononuclear cells obtained from lungs of patients with active
tuberculosis. Increased expression of HLA-DR, a marker of celll activation,
in addition to a significantly higher proportion of cells expressing
dendritic and epitelioid cell markers was verifyed in the tuberculosis
group when compared to normal controls, suggesting that the recruitment
of monocytes and local cell activation are not sufficient to control
this pathogen.
American tegumentary
leishmaniais (ATL) is another disease endemic in Brazil. Its association
with HIV infection has been published by different groups. As shown
by Dr SG Coutinho (FIOCRUZ, Rio de Janeiro), lesions and high parasite
load were associated to a clear depression of T-cell mediated immune
response to Leishmania antigens. The majority of the responsive
cells to Leishmania antigens had the CD8+ phenotype, suggesting
the involvement of this T cell population and the IFN-g production in
the cure of localized cutaneous leismaniasis.
Another relevant
aspect discussed in this meeting was the association between
HIV and Mycobacterium leprae infections. As discussed by Dr E
Sarno (FIOCRUZ, Rio de Janeiro), despite of the low CD4+ counts in peripheral
blood, no histopathological or phenotypic alterations were observed
in the lesions of lepromatous and tuberculoid HIV positive patients,
when compared to HIV negative individuals. The reactivity to the Mitsuda
test as well the the lymphoproliferative response to M. leprae
antigens, usually detected in patiens with tuberculoid lepra, was abrogated
in the HIV-1 co-infected individuals. However, the IFN-g production
in response to the same antigens was similar in both groups. In addition,
overexpression of cytokine genes in non-stimulated peripheral mononuclear
cells from co-infected individuals was verified, giving evidence for
cytokine gene expression even in very low CD4+ cell counts.
Cerebral toxoplasmosis
is one of the most important opportunistic diseases associated to HIV
infection in Brazil, placed in the fourth position in the Epidemiological
Report (PN-DST/AIDS, Brazilian Ministry of Health, Jun-Aug, 1995). Based
on a in vitro model of HIV-1/Toxoplasma gondii co-infection,
Dr R Gazzineli (UFMG/FIOCRUZ, Belo Horizonte) showed that in monocyte/macrophage
cell cultures T. gondii activates and/or potentiates HIV-1 replication,
possibly by the induction of monocyne production. The potential importance
of this enhancement of the HIV replication on the evolution to AIDS
was also discussed.
Concerning the Brazilian
National Plan of HIV-1/AIDS vaccine evaluation, Dr Euclides A Castilho
(FIOCRUZ, Rio de Janeiro/Ministry of Health,DF) informed that in 1991
Brazil has been selected by the Global Programme on AIDS of the World
Health Organization as a site for potential vaccine efficacy trials.
This plan contemplates ethical aspects mainly related with respect,
benevolvence, non-malevolence and justice and involves four different
areas, namely virology, clinical studies, epidemiological studies and
sexual behaviour.
Currently, three
vaccine sites have been established in Brazil: Belo Horizonte, MG, Rio
de Janeiro, RJ and São Paulo, SP. These three centers have conducted
research projects with the following objectives: (a) to evaluate the
feasibility of establishing and maintaining male homosexual/bisexual
cohorts, (b) to determine soro-incidence of HIV infection, (c) to conduct
social behavioral studies in order to understand better the different
risk factors for HIV infection.
Dr Dirceu Greco
(UFMG, Belo Horizonte) reported briefly on the first phase I trial in
Brazil. The HIV-1 synthetic peptide product used in this trial was produced
by the United Biomedical Inc., USA. This product is composed of an octameric
peptide linked by heptalysin, corresponding to the V3 loop of HIV-1
MN isolate. As prescribed in the National Plan for HIV-1 Vaccine Evaluation,
this vaccine had been previously tested in the USA. The general objective
of the trial is to evaluate immunogenicity and safety of this product
in our human and environmental conditions with randomized, double-blinded
and controlled studies. These studies are underway in Belo Horizonte
as well as in Rio de Janeiro and include 15 volunteers in each state.
Based on HIV-1 diversity
observed in Brazil, Dr Bernardo Galvão-Castro briefly summarized
the Ministry of Health strategy to systematically monitor HIV-1 polymorphism
in Brazil. For this purpose, a National Laboratory Network fot HIV-1
Isolation and Characterization was established. The main objectives
of this network are: (1) to develop a system for monitoring the antigenic
variability of HIV-1 isolates from different regions of Brazil, (2)
to generate basic information of genetic and antigenic properties of
epidemiologically relevant HIV-1 strains that will enable the selection
of antigenically appropriate candidate vaccines to be evaluated and
potentially used in Brazil, (3) to participate in other international
HIV-1 characterization efforts as a part of the WHO Network for HIV
Isolation and Characterization, on a bilateral basis of collaboration
with individual international research programs.
The necessity of
maintaining contact between individual research groups in Brazil, in
their national and international research efforts in the field of basic
research revealed in this first Symposium was discussed. It was decided
to hold bienal small meetings such as this first Symposium, and the
FIOCRUZ confirmed its inclination to support future meetings.
This is a Personal
View of the First Brazilian Symposium on Basic Research in HIV-1/AIDS,
with special emphasis on results presented but not published in this
journal issue, as expressed by the authors.

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