Euclid preparation: XVII. Cosmic dawn survey: Spitzer space telescope observations of the Euclid deep fields and calibration fields

Galaxie

Immune restoration does not invariably occur following long term HIV-1 suppression during antiretroviral therapy.

Background: Current antiretroviral treatment can induce significant and sustained virological and immunological responses in HIV-1-infected persons over at least the short- to mid-term. Objectives: In this study, long-term immune reconstitution was investigated during highly active antiretroviral therapy. Methods: Patients enrolled in the INCAS study in The Netherlands were treated for 102 weeks (range 52-144 weeks) with nevirapine (NVP) + zidovudine (ZDV) (n = 9), didanosine (ddl) + ZDV (n 10), or NVP + ddl + ZDV (n = 10). Memory and naive CD4+ and CD8+ T cells were measured using CD45RA and CD27 monoclonal antibodies (mAb), T-cell function was assayed by CD3 + CD28 mAb stimulation, and plasma HIV-1 RNA load was measured by ultra-direct assay (cut-off <20 copies/ml). Results: Compared to both double combination regimens the triple combination regimen resulted in the most sustained increase in CD4+ T cells (change in CD4+ + 253 x 10(6) cells/l; standard error, 79 x 10(6) cells/l) and reduction of plasma HIV-1 RNA. In nine patients (31%) (ddl + ZDV, n = 2; NVP + ddl + ZDV, n = 7) plasma HIV-1 RNA levels remained below cut-off for at least 2 years. On average, these long-term virological responders demonstrated a significantly higher increase of naive and memory CD4+ T cells (P = 0.01 and 0.02, respectively) as compared with patients with a virological failure, and showed improved T-cell function and normalization of the naive: memory CD8+ T-cell ratio. However, individual virological success or failure did not predict the degree of immunological response. T-cell patterns were independent of baseline CD4+ T-cell count, T-cell Function, HIV-1 RNA load or age. Low numbers of naive CD4+ T cells at baseline resulted in modest long-term naive T-cell recovery Conclusions: Patients with prolonged undetectable plasma HIV-1 RNA levels during antiretroviral therapy do not invariably show immune restoration. Naive T-cell recovery in the setting of complete viral suppression is a gradual process, similar to that reported for immune recovery in adults after chemotherapy and bone marrow transplantation. (C) 1999 Lippincott WiiIiams & Wilkins

High-dose nevirapine in previously untreated human immunodeficiency virus type 1-infected persons does not result in sustained suppression of viral replication

High-dose nevirapine treatment has been reported to confer sustained antiretroviral effects, despite a rapid development of resistance. The use of this strategy was evaluated in 20 previously untreated human immunodeficiency virus type 1 (HIV-1) p24 antigenemic persons with CD4 cell counts between 100 and 500/mm3. Treatment consisted of 400 mg of nevirapine, after a 2-week lead-in dose of 200 mg. Rash was the most frequently reported adverse event, occurring in 25%. While sustained declines in p24 antigen levels were observed in the majority, serum HIV-1 RNA load and CD4 cell counts returned to baseline values within 12 weeks in virtually all subjects. The resistance-conferring tyrosine-to-cysteine substitution at reverse transcriptase position 181 was detected after 4 weeks in most subjects. These observations suggest that plasma drug levels attained with high-dose nevirapine were not sufficient to inhibit nevirapine-resistant virus, although they were approximately 2-fold higher than reported IC50 values of resistant viru