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Memórias do Instituto Oswaldo Cruz
Fundação Oswaldo Cruz, Fiocruz
ISSN: 1678-8060 EISSN: 1678-8060
Vol. 91, Num. 3, 1996, pp. 329-334
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Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 91(1), May/June
1996
Report of the First Brazilian Symposium on Basic Research in
HIV/ AIDS
Angra dos Reis, RJ, Brazil
September 13 - 16, 1995
Bernardo Galv o-Castro, Luiz Roberto Ribeiro Castelo Branco,
Mariza Goncalves Morgado*, Vera Bongertz*
Laboratorio Avancado de Saude Publica, Centro de Pesquisa Goncalo
Moniz - FIOCRUZ, Salvador, BA, Brasil *Departamento de
Imunologia, Instituto Oswaldo Cruz, Av. Brasil 4365, 21045-900
Rio de Janeiro, RJ, Brasil
Code Number: OC96064
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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 Galv o-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 S o 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 S o
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.
Fundac o Banco do Brasil, National Research Council (CNPq) and
Petrobras 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, Ribeir o 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 Feny
(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 S o Paulo (LFM Brigido,
Adolfo Lutz Institute, S o 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, S o 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, S o Paulo) showed the presence of the B and F
subtypes among intravenous drug users in S o 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/ l 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, S o 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, S o 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, S o 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 S o 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
Galv o-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.
Copyright 1996 Fundacao Oswaldo Cruz
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