Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CD4 Lymphocyte Count”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,027 records · Page 57Linked to original sources

Disparity in the percentage of CD4+ T lymphocytes and prognosis of HIV-infected intravenous drug users in Malaysia.

The CD4+ T-lymphocyte absolute count (CD4ac), CD4+ T-lymphocyte percentage (CD4%) and total lymphocyte count (Løac) were assessed in HIV-seropositive intravenous drug users (IVDU) with reference to their correlation with the clinical categories A, B, and C as stipulated by the Centre of Disease Control and Prevention, USA (CDC) and with each other. It was found that while the CD4ac and Løac correlated with the clinical categories, CD4% did not. This may suggest that in our local setting, the CD4% may not necessarily be a suitable alternative marker to CD4ac as proposed by CDC. Furthermore, the CD4% of the normal subjects in this study was found to be relatively lower than the reported Caucasian levels. This may indicate that the use of the cut-off level of less than 14% as an AIDS-defining criteria may not be applicable for our HIV-seropositive IVDU. In addition, unlike the CD4ac which correlated directly with CD4% and Løac, the CD4% did not correlate with Løac. Therefore, due to the observed disparity with clinical status of patients and its possibly lower levels in our normal population, CD4% as a marker for staging HIV disease should be used with caution in our setting. Such findings may also have an impact on the use of established markers for the monitoring and classification of HIV-infected individuals in this region.

Adult↗

Treatment of the acquired immune deficiency syndrome-related Kaposi's sarcoma with bleomycin as a single agent.

A nonrandomized trial was conducted to assess the efficiency and toxicity of bleomycin as a single agent in treatment of non-life-threatening AIDS-related Kaposi's sarcoma (KS). Sixty patients were enrolled in this study. They all had a disseminated and progressive non-life-threatening AIDS-related KS associated with systemic symptoms and/or CD4 lymphocyte count less than 400/mm3. Thirty patients were treated with intramuscular bleomycin (5 mg/d for 3 days every 2 or 3 weeks) and 30 others with a slow continuous intravenous infusion of bleomycin (6 mg/m3/d for 4 days every 4 weeks). The mean duration of therapy was 5 months (range, 2 to 24 months). A partial response was observed in 29 patients (48.3%) and the disease was stabilized in 18 additional patients (30%). Bleomycin failed in 21.6% of patients. Therapy had to be discontinued in two patients because of side effects. Thus bleomycin as a single agent is a good alternative therapy for AIDS-related KS.

Acquired Immunodeficiency Syndrome↗

The effect of N-acetylcysteine supplementation upon viral load, CD4, CD8, total lymphocyte count and hematocrit in individuals undergoing antiretroviral treatment.

Individuals infected with the human immunodeficiency virus (HIV-1) present with decreased CD4, a progressive increase in viral load, compromised cell immune defense, and hematologic alterations. The aim of this study was to assess the serum viral load, CD4, CD8, lymphocyte count and hematocrit at the beginning of antiretroviral therapy in individuals who were supplemented with N-acetylcysteine (NAC). Twenty volunteers participated in this double-blind, placebo-controlled 180-day study. Ten participants received 600 mg of NAC per day (NAC group) and the other ten serving as a control group received placebo. The above mentioned parameters were determined before treatment, and after 60, 120 and 180 days. In NAC-treated patients hematocrit remained stable and an increase in CD4 cell count took place earlier than that in the control group.

Acetylcysteine↗

Interpretation of flow cytometric measurement of lymphocytes after fluorescein angiography.

PURPOSE: By use of flow cytometry (FCM), lymphocyte subsets were evaluated with fluorochrome-labeled monoclonal antibodies (MoAbs). Recent fluorescein angiography (FA) produces temporary elevation of serum background fluorescence at certain wavelengths of light, producing falsely decreased lymphocyte subset quantitations. The authors evaluated the duration of this effect on one subset of lymphocytes after FA. METHODS: CD4 counts were determined by FCM before and 10 minutes, 1, 6, and 24 hours after injection of fluorescein dye in 12 patients. The MoAbs used were directly conjugated to fluorescein isothiocyanate (FITC) or phycoerythrin (PE). RESULTS: Using FITC-labeled MoAbs, falsely decreased CD4 counts occurred in all patients at 10 minutes and in all but one patient 1 hour after injection. Return to baseline levels occurred in 50% (95% confidence interval [CI], 0.21, 0.79) by 6 hours and in 75% (95% CI, 0.43, 0.95] by 24 hours. No such effect was observed using PE-labeled MoAbs. CONCLUSIONS: Falsely decreased CD4 values as determined by FCM were present immediately after FA in all 12 patients and persisted 24 hours in some patients when FITC-labeled MoAbs were used. CD4 evaluation should be delayed in patients who have undergone recent FA or the analysis should be performed with PE-labeled MoAbs.

Adult↗

Correlation between intraocular pressure and CD4+ T-lymphocyte counts in patients with human immunodeficiency virus with and without cytomegalovirus retinitis.

PURPOSE: To determine the intraocular pressure in patients with human immunodeficiency virus (HIV) with and without cytomegalovirus retinitis, and to correlate intraocular pressure with CD4+ T-lymphocyte count and the presence, extent, and activity of cytomegalovirus retinitis. METHODS: Intraocular pressure was measured with calibrated Goldmann applanation tonometers in two groups of patients. Group A included 84 patients with HIV (120 eyes) with cytomegalovirus retinitis, and Group B included 110 patients with HIV (183 eyes) without cytomegalovirus retinitis. Thirty-three patients without HIV (66 eyes) were included as a control group. Step-wise regression analysis of intraocular pressure included correlation with cytomegalovirus retinitis (presence, extent, and activity), CD4+ T-lymphocyte count, age, and gender. RESULTS: The mean intraocular pressure was 9.8 mm Hg in Group A, 12.6 mm Hg in Group B, and 16.1 mm Hg in the control group. All three groups were statistically different from each other when intraocular pressure was compared (P < .0001). Step-wise regression showed that low CD4+ T-lymphocyte count (r2 = .20; P < .0001) and extent of cytomegalovirus retinitis (r2 = .08; P = .007) both correlated to low intraocular pressure. CONCLUSION: Intraocular pressure is lower than normal in patients with HIV. Decreased CD4+ T-lymphocyte count is the major association with low intraocular pressure (20% of the effect); extent of cytomegalovirus retinitis accounts for 8% of the effect. Knowledge of the normal range of intraocular pressure in patients with HIV will be important to the understanding and treatment of glaucoma and other disorders or treatments affecting intraocular pressure.

Adult↗

Requirement of interleukin 17 receptor signaling for lung CXC chemokine and granulocyte colony-stimulating factor expression, neutrophil recruitment, and host defense.

Bacterial pneumonia is an increasing complication of HIV infection and inversely correlates with the CD4(+) lymphocyte count. Interleukin (IL)-17 is a cytokine produced principally by CD4(+) T cells, which induces granulopoiesis via granulocyte colony-stimulating factor (G-CSF) production and induces CXC chemokines. We hypothesized that IL-17 receptor (IL-17R) signaling is critical for G-CSF and CXC chemokine production and lung host defenses. To test this, we used a model of Klebsiella pneumoniae lung infection in mice genetically deficient in IL-17R or in mice overexpressing a soluble IL-17R. IL-17R-deficient mice were exquisitely sensitive to intranasal K. pneumoniae with 100% mortality after 48 h compared with only 40% mortality in controls. IL-17R knockout (KO) mice displayed a significant delay in neutrophil recruitment into the alveolar space, and had greater dissemination of K. pneumoniae compared with control mice. This defect was associated with a significant reduction in steady-state levels of G-CSF and macrophage inflammatory protein (MIP)-2 mRNA and protein in the lung in response to the K. pneumoniae challenge in IL-17R KO mice. Thus, IL-17R signaling is critical for optimal production of G-CSF and MIP-2 and local control of pulmonary K. pneumoniae infection. These data support impaired IL-17R signaling as a potential mechanism by which deficiency of CD4 lymphocytes predisposes to bacterial pneumonia.

Animals↗

The effect of complete dentures with a metal palate on candida species growth in HIV-infected patients.

PURPOSE: This in vivo investigation compared the oral candidal population between heat-cured acrylic resin and nickel-chromium-beryllium alloy in maxillary complete dentures in HIV-infected patients. MATERIALS AND METHODS: Split-palate maxillary complete dentures were fabricated for 19 HIV-infected patients: one-half of the palate was made in acrylic resin and the other half in nickel-chromium-beryllium. Patients were divided into low or high CD4+ lymphocyte count groups. Dentures were worn for 5 months. Palatal mucosa was clinically evaluated at baseline, 1, 3, and 5 months after denture insertion. Specimens were collected at 1, 3, and 5 months using a modified imprint culture method. Speciation of Candida was performed using a chromogenic culture medium. Two-sample t-test was employed to determine effects and significant interactions between the control and test groups and the low and high CD4+ lymphocyte groups. A chi(2) test analyzed and compared the results of the clinical evaluation (p < 0.05). RESULTS: Significant differences were observed in the colony counts between both materials during the third (p= 0.046) and fifth months (p= 0.039). The low CD4+ group demonstrated significant differences during the third (p= 0.03) and fifth months (p= 0.05). There were no significant differences between the species of Candida that colonized either material with the exception of Candida dubliniensis (p < 0.001) and "Others" (p < 0.001) during the first and fifth months. There were no significant differences on the clinical appearance of the palatal mucosa between both materials (p= 1.00). CONCLUSIONS: The metal base proved to be effective in decreasing the fungal growth typically present in complete dentures. Although overt clinical manifestations were not present, colony counts of Candida species were high in the acrylic resin denture bases of these patients. This investigation demonstrated that metal base complete dentures provide an important alternative dental service for edentulous HIV-positive and other patients who are particularly prone to higher incidences of fungal infections.

Acrylic Resins↗

Total lymphocyte count as a possible surrogate of CD4 cell count to prioritize eligibility for antiretroviral therapy among HIV-infected individuals in resource-limited settings.

OBJECTIVE: To characterize the value of total lymphocyte counts in predicting risk of death among patients initiating triple combination antiretroviral therapy. METHODS: Study subjects included antiretroviral-naive persons aged 18 years or older who initiated treatment with triple combination therapy between August 1 1996 and September 30 1999 in a population-based observational cohort of HIV-infected individuals. Total lymphocyte counts as well as CD4 count and plasma viral load were assessed at baseline. Separate Cox proportional hazards models were devised to evaluate the effect on survival of total lymphocyte count in lieu of or with CD4 count after adjustment for other prognostic factors including plasma viral load. RESULTS: A total of 733 antiretroviral-naive persons initiated triple drug combination antiretroviral therapy over the study period with a median follow-up of 29.5 months. In the first analysis, only baseline CD4 cell counts of 50-199 cells/microl or less than 50 microl were associated with an increased risk of mortality [adjusted relative risk (ARR) 2.90; 95% CI: 1.40, 5.98] and (ARR 6.30; 95% CI: 2.93, 13.54), respectively. When CD4 counts were excluded from the analysis as if unavailable, total lymphocyte count of between 0.8 and 1.4 G/I, and less than 0.8 G/I were both significantly associated with an increased risk of mortality (ARR 2.36; 95% CI: 1.16, 4.78) and (ARR 6.17; 95% CI: 2.93, 13.01), respectively. CONCLUSION: Total lymphocyte count may provide a simple and cost-effective alternative for prioritizing therapy initiation in resource-limited settings. Our results suggest that, if appropriately validated, judicious application of total lymphocyte counts could overcome one of the practical obstacles to more widespread provision of antiretroviral therapy in resource-poor settings.

Adolescent↗

Prognostic value of an elevated CD8 lymphocyte count in HIV infection. Results of a prospective study of 152 asymptomatic HIV-positive individuals.

OBJECTIVE: To evaluate the prognostic value of an elevated CD8 lymphocyte count in the early stages of HIV infection. DESIGN: A prospective study ongoing since January 1986. METHODS: One hundred and fifty-two asymptomatic HIV-positive individuals with a CD4 lymphocyte count > 400 x 10(6)/l at enrollment were included. Disease progression was defined as a CD4 count < 200 x 10(6)/l. RESULTS: During the follow-up period, CD4 count decreased in 33 individuals; CD8 count increased to > 1500 x 10(6)/l in 38 individuals and doubled in 35. The risk of a decreasing CD4 count was estimated to be 1.7-fold higher, although not significantly so, after the elevation of the CD8 count to > 1500 x 10(6)/l than before or in the absence of such an increase. However, this predictive value disappeared when five baseline parameters found to predict the outcome (neopterin, beta 2-microglobulin, p24 antigen, anti-p18 antibody and immunoglobulin A) were adjusted. CONCLUSION: Elevated CD8 count appears to be a weak marker for disease progression.

Adult↗

Modeling the time course of CD4 T-lymphocyte counts according to the level of virologic rebound in HIV-1-infected patients on highly active antiretroviral therapy.

OBJECTIVE: To study the influence of the level of virologic rebound during combination antiretroviral therapy on the time course of the CD4 count. METHODS: Between January 1997 and December 1999, we enrolled 3736 patients from the French Hospital HIV Database who had an undetectable viral load on a first course of highly active antiretroviral therapy (HAART). Four levels of virologic rebound were defined on the basis of viral load values during the year following initial undetectability on HAART: group 1, all viral loads <500 copies/mL; group 2, all viral loads <5000 copies/mL; group 3, all viral loads <10,000 copies/mL; and group 4, at least 1 viral load >10,000 copies/mL. We developed a continuous time-homogeneous Markov process with 5 reversible stages defined by CD4 count intervals. RESULTS: CD4 counts increased continuously over time in each group. The smaller the virologic rebound, the stronger was the increase in the CD4 count (P < 0.0001). The mean CD4 cell count increments between months 2 and 6 were 26, 20, 11, and 2 cells/mm3 in groups 1, 2, 3, and 4, respectively. The rate of gain fell after month 6 and was almost nil in group 4. CONCLUSION: After achieving an undetectable viral load on HAART, immunologic reconstitution is possible whatever the subsequent level of viral replication, except among patients with high-level rebound, meaning that in patients with a long history of antiretroviral therapy and a reduced choice of antiretroviral drugs due to acquisition of resistances, delay in antiretroviral therapy switch can be possible in patients with low or intermediate rebound.

Adult↗

Clinical significance of human immunodeficiency virus type 1 phenotypes in infected children.

Human immunodeficiency virus type 1 (HIV-1) isolates from perinatally infected infants and children were examined for syncytium-inducing (SI) capacity. All isolates from 14 infants < 1 year old had non-syncytium-inducing (NSI) HIV-1 phenotypes. Within their first year, 10 infants progressed to AIDS and 3 died. Of isolates from 26 children > 2 years old, 13 had SI HIV-1 phenotypes and 13 had NSI strains. Children with SI virus had significantly lower CD4+ cell counts standardized for age and were significantly older than those with NSI strains (P = .008 and .001, respectively); the effect of viral phenotype on CD4+ lymphocytes could not be detected independent of age. In another group, children with SI strains were more likely to show in vitro zidovudine resistance. Results suggest a biphasic response to HIV infection in children. Progression to AIDS may occur rapidly in infants with NSI HIV-1, but older children tend to have SI phenotypes and lower CD4+ lymphocyte counts and more often show zidovudine resistance.

CD4-Positive T-Lymphocytes↗

Tuberculin and anergy testing in HIV-seropositive and HIV-seronegative persons. Pulmonary Complications of HIV Infection Study Group.

OBJECTIVE: To determine the prevalence and predictors of reactivity to tuberculin purified protein derivative (PPD) and skin test anergy in patients with human immunodeficiency virus (HIV) infection and in HIV-seronegative controls. DESIGN: Cross-sectional analysis of baseline data from a prospective, multicenter study of pulmonary complications of HIV infection. SETTING: Community-based cohort of persons with and without HIV infection. PATIENTS: A total of 1171 HIV-seropositive patients without AIDS (841 homosexual men, 274 intravenous drug users, and 56 women with heterosexually acquired infection); 182 HIV-seronegative persons (125 homosexual men and 57 intravenous drug users). MEASUREMENTS: Delayed-type hypersensitivity response to tuberculin PPD, trichophytin, mumps, and Candida antigens; T-lymphocyte subsets. RESULTS: The prevalence of tuberculin PPD reactivity was higher among intravenous drug users than among homosexual men, in both HIV-seronegative (19.1% compared with 6.8%, P = 0.03) and HIV-seropositive persons (15.1% compared with 2.5%, P < 0.001). Among HIV-infected patients, the prevalence of tuberculin reactivity varied directly and that of anergy inversely with the absolute CD4 lymphocyte count. Prevalences were 1% and 72%, respectively, in patients with fewer than 200 CD4 cells/mm3, and 8.4% and 25.5%, respectively, in those with 600 CD4 cells/mm3 (P < 0.001 for both comparisons). Patients with HIV infection and fewer than 400 CD4 lymphocytes/mm3 had a lower prevalence of PPD reactivity than HIV-seronegative controls (2.7% compared with 10.0%, P < 0.001). The strongest predictors of tuberculin reactivity were intravenous drug use, black race, a previous positive PPD test result, and a history of Calmette-Guérin bacillus vaccination. The strongest predictor of anergy was HIV seropositivity. CONCLUSIONS: The response to delayed-type hypersensitivity antigens depends on immune status. The value of PPD and anergy testing in HIV-seropositive patients depends on the ability of such testing to predict subsequent tuberculosis, which is imprecisely known. Until more data or better methods are available, these tests should be done as early as possible in the course of HIV infection.

Adolescent↗

Tuberculosis infection in HIV-infected Indian patients.

Individuals with HIV infection are at increased risk for tuberculosis (TB). The altered CD4 T-cell homeostasis induced by HIV infection may play a key role in the development of tuberculosis in HIV-infected patients. In this retrospective analysis, lymphocyte profiles (CD4 and CD8 count) of subjects infected with HIV, with or without TB, were evaluated. The influence of tuberculosis treatment on the CD4 count in dually infected patients was analyzed in a subset of patients available for follow-up. Of 421 subjects with HIV infection studied, 105 (24.9%) were positive for TB (HIV+TB+). A statistically significant difference (p = 0.0001) was found in the median CD4+ counts between the HIV+TB- (297.5 per microliter) and HIV+TB+ (181 per microliter) groups. TB was found to be the indicator disease for HIV infection in 36 (34.2%). In 65.7% of HIV-infected patients, TB was the first AIDS-defining disease. Of 72 patients who were receiving TB treatment, 33 (45.9%) showed an increase in CD4 counts, but this was statistically not significant. None of these patients was undergoing antiretroviral therapy prior to TB treatment. We conclude from this retrospective study that TB, a common HIV-related opportunistic infection in Indian subjects, is associated with lower CD4+ counts. The influence of TB therapy on CD4 counts in the patients needs to be further investigated.

Adult↗

Semen analysis in human immunodeficiency virus infection.

OBJECTIVE: To examine the effect of human immunodeficiency virus (HIV) infection on semen quality and to investigate the role of clinical stage of infection, mode of virus acquisition, and azidothymidine (AZT) treatment. DESIGN, PATIENTS, MAIN OUTCOME MEASURES: Ejaculates from 39 HIV-seropositive men and 51 seronegative controls were compared using conventional semen analysis parameters. Centers for Disease Control (Atlanta, GA) classification and peripheral blood CD4 lymphocyte count of seropositive men were recorded at the time of semen analysis. Five patients provided semen before and after AZT treatment. RESULTS: Semen from seropositive men contained significantly fewer motile sperm (48.8% versus 58.8%, P = 0.001), more round cells (62% versus 28% subjects with density greater than 1 x 10(6)/mL, P = 0.003), and was more viscous (1.3 versus 0.5 cm, P less than 0.05) than semen from seronegative controls. The proportion of motile sperm was correlated with absolute number (r = 0.49, P = 0.004) and percentage (r = 0.37, P = 0.03) of CD4-positive lymphocytes in peripheral blood. Total sperm output, however, was preserved and was not correlated with lymphocyte count or symptomatic disease. Administration of AZT had no deleterious effect on sperm output or other semen variables. CONCLUSION: Human immunodeficiency virus infection per se does not significantly reduce sperm production, regardless of clinical stage or mode of acquisition; however, HIV-seropositive men produce more viscous semen containing fewer motile sperm and more round cells.

CD4 Antigens↗

Hepatitis G virus infection markers (RNA and anti-E2 antibodies) in a multicenter cohort of hemophiliacs.

BACKGROUND AND OBJECTIVE: To investigate the prevalence and evolution of hepatitis G virus (HGV) infection in hemophiliacs and to correlate evolution of HGV infection markers with immunologic parameters in those patients co-infected with HIV. DESIGN AND METHODS: HGV RNA and anti-E2 antibodies were studied in 124 patients. Serial samples were drawn every 4 months from 1992 to 1996. Lymphocyte subsets including T-helper lymphocytes, T-suppressor lymphocytes, T-cytotoxic lymphocytes, activated T-lymphocytes and natural killer cells were analyzed. RESULTS: Prevalences were 22.6% for HGV RNA and 18.5% for anti-E2. Four patients had both HGV RNA and anti E2, so the overall prevalence of HGV infection in hemophiliacs was 37.9% (11.5% in 200 controls, p<0.0001). After a median follow-up of 36.6 months 20 patients remained HGV RNA positive, whereas HGV RNA had cleared in 8, with an actuarial probability of clearance at 36 months of 34.6%. Only 2 patients developed anti-E2 antibodies. Four patients cleared anti-E2, with an actuarial probability at 36 months of 24.8%. In patients with HIV infection, both lower CD4+ lymphocyte count (p=0.01) or higher CD8+ lymphocyte count (p=0.03) showed predictive value for probability of clearing HGV-RNA. CD4+/CD8+ ratio (p=0.002) was the only variable included in the best model for HGV-RNA disappearance. INTERPRETATION AND CONCLUSIONS: A more accurate estimation of the prevalence of HGV infection can be achieved with the determination of both HGV RNA and anti-E2. Anti-E2 response can be undetectable or transitory after disappearance of HGV-RNA, giving therefore rise to the possibility of underestimating HGV prevalence with currently diagnostic methods. In HIV-positive patients, cellular immune function seems to be involved in the resolution of HGV infection, following the significant correlation found between clearance of HGV-RNA and CD4+/CD8+ lymphocyte populations.

Adolescent↗

Predictor of the rate of CD4 lymphocyte loss in HIV-1-seropositive asymptomatic hemophiliacs by in vitro immunoglobulin synthesis.

The objective of the present study was to evaluate the prognostic utility in determining the risk of AIDS progression in HIV-1-infected asymptomatic hemophiliacs by in vitro immunoglobulin (Ig) synthesis. With this aim, a cohort of 28 HIV-1-seropositive hemophiliacs were studied. All showed the number of CD4 lymphocytes higher than 400 positive cells/mm3. In all cases the spontaneous and pokeweed mitogen-induced in vitro production of Ig by peripheral blood lymphocytes was evaluated at the beginning of the study and the ratio stimulated/spontaneous (Stim/Spon) synthesis was calculated. At the same time, the absolute CD8+ cell count, IgA serum immunoglobulin, p24 HIV-1 antigenemia, and beta2 microglobulin were calculated. These data were monitored during the 4-year follow-up of patients and compared with the stimulated/spontaneous Ig synthesis ratio to evaluate the predictive significance on the progression of HIV infection. According to the stimulated/spontaneous Ig synthesis ratio, hemophilic patients were separated into two categories. Group I included 12 subjects with a Stim/Spon ratio higher than 2 (the lowest value of normal controls) and group II included 16 cases with a ratio lower than 2. As control, in 36 HIV-1-negative hemophiliac individuals the stimulated/spontaneous Ig ratio ranged between 2 and 42; mean +/- SEM, 12.9 +/- 1.8. At the end of the 4-year follow-up, group I patients showed a CD4 count and clinical staging consistent with those of the first evaluation; in contrast group II demonstrated a significant decrease in CD4 lymphocytes and deterioration of clinical conditions. Our results show that a low Stim/Spon Ig ratio when the CD4 lymphocyte count was still normal appears to predict the depletion of this lymphoid subset and progression to AIDS before T CD8, IgA immunoglobulin, p24 HIV-1 antigenemia, and beta2 microglobulin abnormalities. In this setting, the stimulated/spontaneous Ig ratio may represent a useful tool for clinical decisions in HIV-1-infected hemophiliacs.

CD4-Positive T-Lymphocytes↗

Simian immunodeficiency virus infection of CD4+CD8+ T cells in a macaque with an unusually high peripheral CD4+CD8+ T lymphocyte count.

We assessed the possible role in vivo CD4(+) CD8(+) T cells as a viral reservoir for simian immunodeficiency virus (SIV), in a macaque with 50% CD4(+) CD8(+) T cells in peripheral blood. During primary infection (day 14) of this rhesus macaque with the pathogenic SIVmac251 strain, proviruses were detected at similar frequencies in CD4(+) CD8(+) T cells (1/10) and CD4(+) T cells (1/10) and at a lower frequency in CD8(+) T cells (1/800). On day 235, no viral DNA was detected in CD8(+) cells, despite the persistent high viral load, indicating that CD8(+) cells do not constitute a reservoir during the chronic phase of SIV infection. Infection induced early lymphopenia of CD4(+), CD4(+) CD8(+), and CD8(+) cells; only the CD8(+) cell population returned to initial levels and expanded further. We found that CD4(+) CD8(+) T cells expressed the costimulatory CD28 molecule less and were more prone to die in vitro after phytohemagglutinin/interleukin 2 stimulation than were CD4(+) T cells. Taken together, massive death of CD4(+) CD8(+) T cells during acute stages of SIV infection may explain why CD8(+) T cells did not represent a major reservoir for SIV at the onset of infection.

Animals↗