ABSTRACT
Immune responses to HIV-1 infection of 42 HIV-1-positive asymptomatic intravenous drug users (IVDUs) were compared with those of 135 HIV-1-infected asymptomatic homosexual men in the present study. Twenty-five HIV-1(-) individuals served as normal controls. The comparison included antibody responses to five computer-predicted epitopes of HIV-1 p17, and viral proteins gp120 and p24 as well as p17. Major immunophenotypes were also investigated. Results showed that antibody responses to the five epitopes were significantly higher in the IVDUs. A larger proportion of the IVDUs, with respect to that of homosexuals, showed positive antibody responses to p24 and p17, respectively. However, the antibody response to gp120 was similar between the two cohorts. Immunophenotyping showed that HIV-1(+) homosexuals had higher profiles in most of the major subsets than did the IVDUs, especially in the total count of lymphocytes, absolute numbers of CD3+ cells and CD8+ cells. It appeared that the HIV-1(+) IVDU cohort had higher antibody responses to most of the viral antigens, but had lower levels of lymphocyte subsets in comparison with HIV(+) homosexuals.
Subject(s)
HIV Antigens/immunology , HIV Infections/immunology , HIV-1/immunology , Homosexuality , Substance Abuse, Intravenous/immunology , Antibody Formation , Cohort Studies , HIV Seropositivity/immunology , Humans , ImmunophenotypingABSTRACT
A 32-bp deletion on the CCR5 gene (ccr5delta32) confers resistance to HIV-1 infection. This deletion is common in Caucasians, but rare in Asians. Since the frequency of the ccr5delta32 allele of Chinese in mainland China has been unknown we investigated the ccr5delta32 mutation in a cohort of 407 Chinese people in this area. A 225-bp fragment of CCR5 encompassing the 32-bp region was analysed by PCR, hybridization and sequencing. Only 1 out of 407 subjects was heterozygous for ccr5delta32 and no homozygotes were detected. The frequency of ccr5delta32 in this cohort is thus 0.00123, i.e. much lower than that of Caucasians. The ccr5delta32 heterozygote is a healthy young man. To our knowledge this is the first ccr5delta32 mutant found in Chinese people. The results indicate that ccr5delta32 does exist in Chinese people, but at very low frequency. This suggests that ccr5delta32 is not a significant factor for the genetic resistance to HIV-1 in Chinese people.
Subject(s)
Asian People/genetics , Gene Deletion , Genetic Predisposition to Disease/epidemiology , HIV Infections/ethnology , HIV Infections/genetics , Receptors, CCR5/genetics , Adult , Aged , Alleles , Base Sequence , China/epidemiology , Cohort Studies , Female , Gene Frequency , Genetics, Population , Humans , Male , Middle Aged , Molecular Sequence Data , Polymerase Chain Reaction , White People/geneticsABSTRACT
Fc gamma RIII on neutrophils is a phosphatidyl inositol glycan (PIG)-anchored protein that can be released from the cells by activation with chemotactic peptides. We have examined the expression of Fc gamma RIII (CD16), CD11b, and Fc gamma RII (CD32) on neutrophils from human immunodeficiency virus (HIV)-I-infected individuals by two-color FACS. In patients with AIDS and AIDS-related complex and in HIV-I positive intravenous drug abusers we observed a substantial population (25%) of neutrophils that were autofluorescent, and did not stain with the anti-Fc gamma RIII mAb 3G8. This population was largely absent (3%) in HIV-I negative control individuals. No changes in the expression of Fc gamma RII, CD11b, or another PIG-anchored protein, decay accelerating factor (CD55) on neutrophils, were found. The presence of the Fc gamma RIII negative neutrophil population may be related to altered functions leading to common bacterial infections in advanced AIDS.