Concurrent nonavalent human papillomavirus (HPV) vaccination and immune stimulation with imiquimod to treat recalcitrant HPV-associated high grade vaginal intra-epithelial neoplasia.

This is the first report describing detailed T cell responses to viral-like proteins contained in an HPV specific vaccine given in combination with Imiquimod for treatment of persistent VAIN2/3. We postulate that stimulation of the innate immune system with Imiquimod and the specific CD4 and CD8T cell responses following HPV vaccination with Gardasil9@ combined to induce clinical remission in a woman with treatment-refractory disease.

Mucosal-associated invariant T (MAIT) cells are activated in the gastrointestinal tissue of patients with combination ipilimumab and nivolumab therapy-related colitis in a pathology distinct from ulcerative colitis.

The aim of this study was to investigate the pathogenesis of combination ipilimumab and nivolumab-associated colitis (IN-COL) by measuring gut-derived and peripheral blood mononuclear cell (GMNC; PBMC) profiles. We studied GMNC and PBMC from patients with IN-COL, IN-treated with no adverse-events (IN-NAE), ulcerative colitis (UC) and healthy volunteers using flow cytometry. In the gastrointestinal-derived cells we found high levels of activated CD8+ T cells and mucosal-associated invariant T (MAIT) cells in IN-COL, changes that were not evident in IN-NAE or UC. UC, but not IN-C, was associated with a high proportion of regulatory T cells (Treg ). We sought to determine if local tissue responses could be measured in peripheral blood. Peripherally, checkpoint inhibition instigated a rise in activated memory CD4+ and CD8+ T cells, regardless of colitis. Low circulating MAIT cells at baseline was associated with IN-COL patients compared with IN-NAE in one of two cohorts. UC, but not IN-COL, was associated with high levels of circulating plasmablasts. In summary, the alterations in T cell subsets measured in IN-COL-affected tissue, characterized by high levels of activated CD8+ T cells and MAIT cells and a low proportion of Treg , reflected a pathology distinct from UC. These tissue changes differed from the periphery, where T cell activation was a widespread on-treatment effect, and circulating MAIT cell count was low but not reliably predictive of colitis.

Hepatitis C-specific effector and regulatory CD4 T-cell responses are associated with the outcomes of primary infection.

Clearance of primary hepatitis C virus (HCV) infection has been associated with strong and broadly targeted cellular immune responses. This study aimed to characterize HCV-specific CD4+ effector and regulatory T-cell numbers and cytokine production during primary infection. Antigen-specific CD4+ T-cell responses were investigated in a longitudinal cohort of subjects from pre-infection to postoutcome, including subjects who cleared [n=12] or became chronically infected [n=17]. A cross-sectional cohort with previously cleared, or chronic infection [n=15 for each], was also studied. Peripheral blood mononuclear cells were incubated with HCV antigens and surface stained for T-effector (CD4+CD25high CD134+CD39-) and T-regulatory (CD4+CD25high CD134+CD39+) markers, and culture supernatants assayed for cytokine production. Contrary to expectations, the breadth and magnitude of the HCV-specific CD4+ T-cell responses were higher in subjects who became chronically infected. Subjects who cleared the virus had HCV-specific CD4+ T-cell responses dominated by effector T cells and produced higher levels of IFN-γ, in contrast to HCV-specific CD4+ T-cell responses dominated by regulatory T cells and more IL-10 production in those who became chronically infected. Better understanding of the role of antigen-specific CD4+ T-cell responses in primary HCV will further define pathogenesis and help guide development of a preventative vaccine.

Group 2 innate lymphoid cells (ILC2s) are increased in chronic rhinosinusitis with nasal polyps or eosinophilia.

BACKGROUND: Chronic rhinosinusitis (CRS) is a heterogeneous disease with an uncertain pathogenesis. Group 2 innate lymphoid cells (ILC2s) represent a recently discovered cell population which has been implicated in driving Th2 inflammation in CRS; however, their relationship with clinical disease characteristics has yet to be investigated. OBJECTIVE: The aim of this study was to identify ILC2s in sinus mucosa in patients with CRS and controls and compare ILC2s across characteristics of disease. METHODS: A cross-sectional study of patients with CRS undergoing endoscopic sinus surgery was conducted. Sinus mucosal biopsies were obtained during surgery and control tissue from patients undergoing pituitary tumour resection through transphenoidal approach. ILC2s were identified as CD45(+) Lin(-) CD127(+) CD4(-) CD8(-) CRTH2(CD294)(+) CD161(+) cells in single cell suspensions through flow cytometry. ILC2 frequencies, measured as a percentage of CD45(+) cells, were compared across CRS phenotype, endotype, inflammatory CRS subtype and other disease characteristics including blood eosinophils, serum IgE, asthma status and nasal symptom score. RESULTS: 35 patients (40% female, age 48 ± 17 years) including 13 with eosinophilic CRS (eCRS), 13 with non-eCRS and 9 controls were recruited. ILC2 frequencies were associated with the presence of nasal polyps (P = 0.002) as well as high tissue eosinophilia (P = 0.004) and eosinophil-dominant CRS (P = 0.001) (Mann-Whitney U). They were also associated with increased blood eosinophilia (P = 0.005). There were no significant associations found between ILC2s and serum total IgE and allergic disease. In the CRS with nasal polyps (CRSwNP) population, ILC2s were increased in patients with co-existing asthma (P = 0.03). ILC2s were also correlated with worsening nasal symptom score in CRS (P = 0.04). CONCLUSION AND CLINICAL RELEVANCE: As ILC2s are elevated in patients with CRSwNP, they may drive nasal polyp formation in CRS. ILC2s are also linked with high tissue and blood eosinophilia and have a potential role in the activation and survival of eosinophils during the Th2 immune response. The association of innate lymphoid cells in CRS provides insights into its pathogenesis.

Phase I clinical trial of a human idiotypic p53 vaccine in patients with advanced malignancy.

BACKGROUND: The purpose of this study was to induce immunity to p53 by using an idiotypic vaccine, composed of a pool of eight peptides derived from the complimentarity determining regions (CDRs) of human anti-p53 antibodies. PATIENTS AND METHODS: Subjects with advanced malignancy received up to four, monthly intradermal injections of pooled peptides (500 microg of each) admixed with granulocyte-macrophage colony-stimulating factor (GM-CSF; 100 microg). In addition, two sheep and two rabbits were also vaccinated with the pooled peptides. RESULTS: Fourteen subjects were enrolled into the study and six of these completed the vaccination schedule. The vaccine was well tolerated by all subjects and no major adverse events were attributable to the vaccine. All subjects mounted in vivo delayed type hypersensitivity (DTH) responses to two or more of the individual vaccine peptides. Vaccine-induced antibodies specific for peptides 2, 5 or 8 were detected in four of six subjects, and two of these had vaccine-specific, cell-mediated responses. Increasing titers of p53-specific antibodies were found in one patient. No T-cell response to p53 was observed in any of the subjects. All animals developed humoral immunity to the peptides and one of the sheep developed rising serum titers of anti-p53 antibodies. CONCLUSIONS: Vaccination with human antibody CDR regions represents a novel method for inducing human antibodies, which may in turn serve as immunological mimics of p53.

Characterization of the phenotypic and lymphokine profile associated with strong CD8+ anti-HIV-1 suppressor activity (CASA).

A panel of 22 CD8+ T cell lines, with a broad range of CD8+ anti-HIV-1 suppressor activity (CASA) were generated from a single patient with HIV-1 infection. CD8+ T cell lines with either strong or weak CASA were examined and compared for cell surface and intracellular markers, constitutive chemokine and lymphokine mRNA levels and inducible lymphokine expression. Strong CASA significantly correlated with CD8+ T cell lines that highly coexpressed the molecule CD28+ (r=0.52, P=0.01) and Ki67+ (r=0.88, P=0.02), with strong CASA CD8+ T cell lines demonstrating significantly higher (P < 0.05) expression of CD8+CD28+ and CD8+Ki67+ compared to those with weak activity. No such correlations or findings were observed for the markers CD38, HLA-DR, CD57 or perforin. The Th1 cytokines were expressed at greater levels than the Th2 cytokines, with strong CASA significantly associated with an increased inducible level of IL-2 production (P=0.05). Constitutive RANTES, IP-10 and I-309 mRNA expression were significantly (P < 0.05) elevated in CD8+ T cell lines exhibiting strong CASA compared to those with weak CASA. There was no significant difference in the mRNA expression of the lymphokines IL-2, 4, 5, 8, 9, 10, 14, 15, or chemokines MIP-1alpha, MIP-1beta, MCP-1, and Ltn. Strong CASA was therefore associated with rapidly replicating CD8+ T cells of the phenotype CD8+CD28+Ki67+ that expressed greater levels of IL-2 and the ligands RANTES and I-309.

Novel deletion of HIV type 1 reverse transcriptase residue 69 conferring selective high-level resistance to nevirapine.

A novel deletion of residue 69 of the HIV-1 reverse transcriptase (RT) gene was detected in combination with mutations V75I/V and F77L/F in a patient with partial virological response to several antiretroviral drug regimens, including stavudine (D4T), didanosine (DDI), lamivudine (3TC), saquinavir (SQV), and nevirapine (NVP). Longitudinal analysis of samples revealed that this deletion emerged upon reinitiation DDI/D4T therapy following a toxicity-induced short discontinuation of all antiretrovirals. Analysis of the resistance phenotype showed a greater than 62-fold increase of the IC50 of NVP, but no significant change in sensitivity to other single nonnucleoside reverse transcriptase inhibitors (NNRTIs). The mutated virus showed only a moderately reduced sensitivity to DDI (6.7-fold) and D4T (4.8 fold). In a subsequent sample 3 months later additional RT mutations were found, including A62V, Y188L, and Q151M, conferring high-level cross-resistance to multiple nucleoside analogs. Our findings provide evidence that the deletion of RT residue 69 selectively confers high-level NVP resistance.

An examination of signs of disease progression in survivors of the Sydney Blood Bank Cohort (SBBC).

BACKGROUND: The Sydney Blood Bank Cohort (SBBC) was infected between 1981 and 1984 with a nef/LTR defective strain of HIV-1. Different responses to HIV-1 infection have emerged between cohort members in the last 5 years. Three recipients (C135, C64 and C49) remain asymptomatic, have normal CD4 T cell counts, below detection (BD) viral loads (VL), remain therapy naive and are termed long-term non-progressors (LTNP). The donor (D36) and the two recipients (C98 and C54) have significantly declining CD4 T cell counts, detectable VL and are now long-term survivors (LTS). In contrast, in the SA cohort, comparison study group for the SBBC, five of 24 remain therapy naïve after 15 years infection with HIV-1 and all have detectable VL. OBJECTIVES: This paper examines different outcomes to long-term infection with HIV-1 in the SBBC and provides a brief overview of the therapy naïve in a comparison study group, the SA cohort. STUDY DESIGN: Retrospective epidemiological follow-up of the SBBC and the SA cohort has been conducted for >15 years. Analysis of CD4 T cell counts, VL and intermittent monitoring of HIV-specific proliferative responses are reviewed. Viral sequence changes in the SBBC will be considered. RESULTS: Prior to therapy D36 had a CD4 T cell count of 160/mm(3) and plasma VL of 9900 copies/ml while C98 had a CD4 T cell count of 387/mm(3) and plasma VL of 11491 copies/ml. After 1 month of therapy, plasma VL was BD (<400 copies/ml) and both showed significant increase in CD4 T cell counts. Molecular changes have occurred in D36 and C98 viral strains, the most recently evolved quasispecies have larger deletions in the nef/LTR region. CONCLUSIONS: Infection with nef/LTR deleted HIV-1 has resulted in slower disease progression for the SBBC. The three LTNP have maintained normal low levels of activated CD8 T cells and strong HIV-specific proliferative responses to HIV-1 p24, which are associated with control of viral replication.

Impact of HIV type 1 protease, reverse transcriptase, cleavage site, and p6 mutations on the virological response to quadruple therapy with saquinavir, ritonavir, and two nucleoside analogs.

Genotype alterations of HIV-1 protease, reverse transcriptase, cleavage sites p7/p1 and p1/p6, as well as p6(gag) and transframe protein p6* were studied in an observational cohort of 42 individuals who received antiretroviral therapy consisting of saquinavir, ritonavir, and two nucleoside analogs. In a multivariate logistic regression analysis, the prior protease inhibitor experience (odds ratio, 6.20; 95% CI, 1.22-31.38) and the presence of primary protease mutations (odds ratio, 9.99; 95% CI, 1.05-94.72) were independently associated with virological failure. Moreover, a trend was observed in that individuals with N-terminal amino acid insertions in the proline-rich motif of the p6(gag) protein were less likely to experience virological failure (OR, 0.17; 95% CI, 0.02-1.35; p = 0.09). In contrast, the presence of secondary protease, reverse transcriptase, or cleavage site mutations was not independently associated with treatment failure. However, mutations at cleavage site p7/p1 (p = 0.01) and C-terminal p6* mutations (p = 0.02) were both associated with primary protease mutations. In conclusion, the presence of primary protease mutations was the most important predictor of the subsequent virological response. Moreover, there is some evidence that insertions in the proline-rich area of the p6(gag) protein may affect the virological response. The relationship between mutations of cleavage sites or C-terminal p6* residues and protease mutations suggests that these alterations may serve a compensatory role, increasing viral fitness.

Increased turnover of CCR5+ and redistribution of CCR5- CD4 T lymphocytes during primary human immunodeficiency virus type 1 infection.

CCR5 is the major coreceptor for human immunodeficiency virus (HIV) type 1 during primary infection. CCR5+ CD4 T lymphocytes were studied in subjects with primary HIV-1 infection (PHI) or acute Epstein-Barr virus (EBV) infection and in HIV-uninfected controls. The early decline of CD4 T lymphocytes during PHI resulted from depletion of CCR5- CD4 T lymphocytes. After antiretroviral therapy, Ki-67- CCR5- CD4 T cell counts rapidly increased in the circulation, which suggests that the initial decrease was due to an alteration in trafficking and/or sequestration. In the CCR5+ subset of CD4 T cells, there was an elevation in the proliferative (Ki-67+) fraction during PHI, yet their total number remained in the normal range. In contrast, in acute EBV infection, proliferating CCR5+ CD4 T cells accumulated to very high levels, suggesting they have an important role in the early antiviral response, which may be impaired in HIV-1 infection.

Relative significance of different pathways of immune reconstitution in HIV type 1 infection as estimated by mathematical modeling.

A major goal of antiretroviral HIV-1 therapy is the reversal of HIV-1-associated immunological dysfunction. However, the pathogenetic mechanisms involved and their significance are largely unknown. On the basis of the life cycle of naive, activated, and memory CD4(+) T cell subsets, a mathematical model of immune reconstitution was developed and applied to data for T cell subsets in individuals with acute or chronic HIV-1 infection receiving antiretroviral therapy. The final model that most accurately fitted the data, and resulted in realistic estimates for CD4(+) T cell turnover, considered three pathways of immune reconstitution for naive cells, including thymic production, peripheral expansion, and redistribution of naive cells from lymphoid tissue. The reconstitution of the memory compartment was fitted through differentiation and expansion of naive cells and peripheral expansion of memory cells as well as redistribution of memory cells trapped in the lymphoid tissue. Estimated median half-lives for naive and memory CD4(+) T cells were 114 and 21 days, while total production rates were 9.1 x 10(7) and 2.4 x 10(9) cells/day, respectively. Peripheral expansion and thymic production contributed equally to the regeneration of naive cells, but peripheral expansion of memory cells was larger than production of these cells by differentiation of naive cells. A comparison of immune reconstitution in acute and chronic HIV-1 infection revealed that, after adjustment for age, the main difference was the more rapid release of a larger number of naive cells in treated acute HIV-1 infection. Thymic function and peripheral expansion rates, however, were similar in both cohorts.

HIV induces lymphocyte apoptosis by a p53-initiated, mitochondrial-mediated mechanism.

HIV-1 induces apoptosis and leads to CD4+ T-lymphocyte depletion in humans. It is still unclear whether HIV-1 kills infected cells directly or indirectly. To elucidate the mechanisms of HIV-1-induced apoptosis, we infected human CD4+ T cells with HIV-1. Enzymatic analysis with fluorometric substrates showed that caspase 2, 3, and 9 were activated in CD4+ T cells with peak levels 48 h after infection. Immunoblotting analysis confirmed the cleavage of pro-caspase 3 and 9, and of specific caspase substrates. Release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria was observed in HIV-infected cells. The cytochrome c and AIF release preceded the reduction of the mitochondrial transmembrane potential and nuclear chromatin condensation. H IV infection led to phosphorylation of p53 at the Ser15 residue, detectable as early as 24 h after infection. The p53 phosphorylation was followed by increased mRNA and protein expression of p21, Bax, HDM2, and p53. Up-regulation of surface FasL expression, accompanied by a down-regulation of Fas-associated proteins (FADD, DAXX, and RIP), was observed 72 h after infection. Our results suggest that HIV activates the p53 pathway, leading to cytochrome c and AIF release with ensuing caspase activation.

Rapid restoration of CD4 T cell subsets in subjects receiving antiretroviral therapy during primary HIV-1 infection.

OBJECTIVE: To compare the effect of highly active antiretroviral therapy on immune reconstitution in subjects with acute and chronic HIV-1 infection. DESIGN: Prospective study including 58 treatment-naive subjects who commenced indinavir or nelfinavir and two nucleosides during primary (PHI; n = 28) or chronic HIV-1 infection (CHI; n = 30). METHODS: Naive (CD45RA+ 62L+), memory (CD45RA-) and activated (CD38+ HLA-DR+) T cell subsets were quantified at 1-2 monthly time intervals using 4-colour flow cytometry. RESULTS: At 1 year, HIV-1 RNA declined in both cohorts to undetectable levels (< 50 copies/ml), while median CD4 lymphocyte count increased from 470 to 758 x 10(6) cells/l in PHI and from 204 to 310 x 10(6) cells/l in CHI, reaching > 500 x 10(6) cells/l in 93% of PHI, but only in 37% of CHI subjects (P < 0.001). Naive CD4 lymphocytes increased from 106 to 176 x 10(6) cells/l in PHI and from 41 to 44 x 10(6) cells/l in CHI (PHI versus CHI at 12 months: P = 0.003), while memory cells rose from 368 to 573 x 10(6) cells/l in PHI and from 148 to 223 x 10(6) cells/l in CHI (P < 0.001). Early increases (< 3 months) of CD4 lymphocytes were larger in subjects with PHI, consisting of naive CD45RA+ CD62L+ as well as memory CD45RA- CD62L+ cells (P = 0.001). CD4 activation declined from 5 to 2% in PHI and from 13 to 6% in CHI (P = 0.001), while CD8 cell activation was reduced from 33 to 15% in PHI and from 42 to 19% in CHI (P = 0.02). CONCLUSION: Immune reconstitution was more complete, occurred earlier and comprised both naive and memory CD4 T lymphocytes in subjects who commenced antiretroviral therapy during primary HIV-1 infection.

Long-term immunological response in HIV-1-infected subjects receiving potent antiretroviral therapy.

OBJECTIVE: To determine the long-term T-lymphocyte response to highly active antiretroviral therapy (HAART) and to define predictors of the immunological response. DESIGN: Cohort study, including 135 HIV-1-infected subjects at a city general practice who commenced HAART between 1996 and 1998. METHODS: Collection of plasma HIV-1 RNA, CD4+ and CD8+ T-lymphocyte data at 3-6 monthly time intervals over 2 years. RESULTS: Seventy-three subjects (54%) achieved suppression of plasma HIV-1 RNA to levels below 400 copies/ml during the observation period, 31 individuals (23%) had detectable plasma HIV-1 RNA below 10,000 copies/ml and 31 subjects (23%) had virological failures with viral loads above 10,000 copies/mL. Median CD4+ T lymphocytes increased from 246 to 463 x 10(6) cells/l, showing a median rise of 20 x 10(6) cells/l per month in the first 3 months and 7 x 10(6) cells/l per month thereafter. The proportion of individuals who reached CD4+ cell counts above 500 x 10(6) cells/l increased from 8% at baseline to 54% at 2 years. Treatment-naïve individuals, subjects with a large reduction of HIV-1 RNA or a large early CD8+ increase had better early CD4+ responses. Long-term CD4+ T-cell increases were inversely correlated with mean plasma HIV-1 RNA levels. Baseline CD4+ T-cell count was the most important determinant of reaching CD4+ cell counts above 500 x 10(6) cells/l. Nineteen per cent of subjects had no further CD4+ T-cell increases in the second year of therapy despite undetectable viral load. CONCLUSIONS: Immune reconstitution is a slow process, showing a large individual variability. The virological response to HAART was the most important determinant of the immunological short- and long-term response.

Effect of long-term infection with nef-defective attenuated HIV type 1 on CD4+ and CD8+ T lymphocytes: increased CD45RO+CD4+ T lymphocytes and limited activation of CD8+ T lymphocytes.

Members of the Sydney Blood Bank Cohort (SBBC) have been infected with an attenuated strain of HIV-1 with a natural nef/LTR mutation and have maintained relatively stable CD4+ T lymphocyte counts for 14-18 years. Flow cytometric analysis was used to examine the phenotype of CD4+ and CD8+ T lymphocytes in these subjects, including the immunologically important naive (CD45RA+CD62L+), primed (CD45RO+), and activated (CD38+HLA-DR+ and CD28-) subsets. The median values were compared between the SBBC and control groups, comprising age-, sex-, and transfusion-matched HIV-1-uninfected subjects; transfusion-acquired HIV-1-positive LTNPs; and sexually acquired HIV-1-positive LTNPs. Members of the SBBC not only had normal levels of naive CD4+ and CD8+ T lymphocytes, but had primed CD45RO+ CD4+ T lymphocytes at or above normal levels. Furthermore, these primed cells expressed markers suggesting recent exposure to specific antigen. SBBC members exhibited variable activation of CD8+ T lymphocytes. In particular, SBBC members with undetectable plasma HIV-1 RNA had normal levels of activated CD8+ T lymphocytes. Therefore, the result of long-term infection with natural nef/LTR mutant HIV-1 in these subjects suggests a decreased cytopathic effect of attenuated HIV-1 on susceptible activated CD4+ T lymphocyte subsets in vivo, and minimal activation of CD8+ T lymphocytes.

Phenotypic analysis of CD8+ T lymphocytes in a cohort of HIV type 1-infected patients treated with saquinavir, ritonavir, and two nucleoside analogs for 1 year, and association with plasma HIV type 1 RNA.

The phenotype of circulating CD8+ T lymphocytes and its association with plasma HIV-1 RNA were analyzed in 34 HIV-1-infected subjects, who were treated with saquinavir, ritonavir, and two nucleoside analogs (HAART) for 1 year. Four-color flow cytometry was applied to measure the expression of cell surface antigens CD38, HLA-DR, CD45RA, CD28, and CD62L on CD8+ T lymphocytes. The results were compared with data on 35 HIV-1-seronegative subjects, 18 untreated asymptomatic HIV-1-seropositive individuals, and 24 HIV-1-infected subjects receiving reverse transcriptase inhibitors (RTIs). Subjects receiving HAART showed a significantly elevated number and percentage of CD38- and HLA-DR-positive and CD28-negative CD8+ T lymphocytes as well as a lower percentage of naive (CD45RA+62L+) CD8+ T lymphocytes compared with HIV-1-uninfected controls. Even subjects with undetectable plasma HIV-1 RNA showed a persistent elevation of activated CD8+ T lymphocytes. However, fewer activated CD8+ T lymphocytes were observed in subjects receiving HAART than in untreated individuals and subjects administered RTIs. In individuals receiving RTIs, CD8+ cell activation was not significantly reduced compared with untreated subjects. Of all evaluated activation markers, the percentage of CD8+ T lymphocytes expressing CD38 and the combination of CD38 and HLA-DR showed the best correlation with plasma HIV-1 RNA. The persistence of CD8+ T lymphocyte activation in subjects receiving HAART strongly suggests ongoing viral activity, even in subjects with undetectable plasma HIV-1 RNA. A complete normalization of immunologic changes of CD8+ T lymphocytes would therefore require a more potent drug regimen or a longer duration of therapy.

Potent antiretroviral therapy of primary human immunodeficiency virus type 1 (HIV-1) infection: partial normalization of T lymphocyte subsets and limited reduction of HIV-1 DNA despite clearance of plasma viremia.

Antiretroviral therapy commenced during primary human immunodeficiency virus type 1 (HIV-1) infection (PHI) may limit the extent of viral replication and prevent early loss of HIV-specific CD4 lymphocyte function. We studied the effect of current standard therapy (2 nucleoside analogues and a protease inhibitor) in 16 patients with symptomatic PHI. In the 13 patients who completed 1 year of treatment, plasma HIV RNA was <50 copies/mL and median CD4 cell counts were comparable to HIV-uninfected controls, with naive (CD45RA+CD62L+), primed (CD45RO+), and T cell receptor Vbeta subsets all within normal ranges. However, HIV-1 DNA levels in treated and untreated PHI patients were similar. Furthermore, CD8 cell counts remained elevated, including activated (CD38+HLA-DR+), replicating (Ki-67+), and cytotoxic (perforin+CD28-) lymphocytes. In conclusion, early antiretroviral therapy resulted in clearance of viremia and prevented loss of crucial CD4 subsets. The persistence of HIV-1 DNA together with increased CD8 T lymphocyte turnover and activation indicate continued expression of viral antigens.

CD8+ anti-human immunodeficiency virus suppressor activity (CASA) in response to antiretroviral therapy: loss of CASA is associated with loss of viremia.

CD8+ anti-human immunodeficiency virus (HIV) suppressor activity (CASA) defines the noncytolytic suppression of HIV mediated by secreted soluble factors. Changes in CASA in patients receiving combination antiretroviral therapy have not been described. Thirty-two HIV-infected patients receiving mono- or dual therapy for 52 weeks followed by highly active antiretroviral therapy (HAART) for a further 52 weeks were analyzed. T cell number and functional subsets, cutaneous delayed-type hypersensitivity, and plasma HIV RNA were assessed in 17 patients for CASA. Prior to therapy, CASA correlated inversely with HIV RNA (P<.001). Dual therapy yielded greater and more sustained changes in CASA than monotherapy, but HAART decreased CASA to levels observed in HIV-uninfected individuals. The magnitude of HIV RNA suppression correlated significantly with a decrease in activated CD8+ T lymphocytes (CD38+HLA-DR+), increases in naive CD4+ T lymphocytes (CD45RA+62L+), and increases in the delayed-type hypersensitivity score. However, changes in CASA did not correlate with changes in any T lymphocyte subset. CASA increases with improving immune function but appears more dependent on ongoing HIV replication.

Immune reconstitution in HIV-1 infected subjects treated with potent antiretroviral therapy.

The introduction of potent antiretroviral drug regimens contributed to a decline in HIV-1 associated morbidity and mortality. Clinical observations of spontaneous remission of previously untreatable opportunistic infections in subjects on highly active antiretroviral therapy (HAART) reflect the substantial degree of immune reconstitution which can be achieved by those therapies. A biphasic increase of CD4+ T lymphocytes has been reported including naive (CD45RA+) and memory (CD45RO+) cell subsets. Proliferative lymphocyte responses to recall antigens and mitogens are enhanced over time, while T lymphocyte activation is largely reduced and T cell receptor (TCR) repertoires are partly restored. Proliferative lymphocyte responses specific to HIV-1 antigens, in contrast, remain weak. A complete normalisation of HIV-1 associated immunological alterations has not been reported so far, but the observation period of subjects on potent antiretroviral therapies is still relatively short.

Impact of early HIV-1 RNA and T-lymphocyte dynamics during primary HIV-1 infection on the subsequent course of HIV-1 RNA levels and CD4+ T-lymphocyte counts in the first year of HIV-1 infection. Sydney Primary HIV Infection Study Group.

Plasma HIV-1 RNA and CD4+ T-cell counts after HIV-1 seroconversion are important independent markers that predict the clinical course of HIV-1 infection. The prognostic significance of these parameters during primary HIV-1 infection, however, remains largely unknown. In a cohort of 53 male study subjects (age, 33 +/- 7 years), who consecutively presented with primary HIV-1 infection, we analyzed the relationship between early plasma HIV-1 RNA, CD4+ and CD8+ T-cell counts, beta2-microglobulin, and p24-antigen levels determined in the first 3 months and subsequent plasma HIV-1 RNA levels and CD4+ T-cell counts 6 to 12 months after onset of primary symptoms. Peak, nadir, and median HIV-1 RNA levels in the first 30 days were already significantly associated with HIV-1 RNA levels at 6 to 12 months (p = .02, p < .0001, and p = .01, respectively). Similarly, early nadir and median CD4+ T-lymphocyte counts in the first 30 days showed a significant relationship with CD4+ T-cell counts at 6 to 12 months (p = .009 and p = .0008, respectively). Study subjects with an early decline of CD4+ counts to <500 cells/microl had an eightfold higher risk that CD4+ counts were <500 cells/microl at 1 year. Of all evaluated virologic parameters, only nadir HIV-1 RNA at 76 days predicted CD4+ counts at 6 to 12 months (p = .006). Early HIV-1 RNA levels and CD4+ counts are already associated with the time course of those parameters 6 to 12 months after onset of symptoms. Nadir viral load was the strongest predictor of HIV-1 RNA levels as well as of CD4+ counts at 6 to 12 months. An early decline of CD4+ T lymphocytes may be a useful clinical prognostic marker for rapid disease progression.