301 research outputs found
Impact of HIV on CD8+ T Cell CD57 Expression Is Distinct from That of CMV and Aging
Background: Chronic antigenic stimulation by cytomegalovirus (CMV) is thought to increase ââimmunosenesenceââ of aging, characterized by accumulation of terminally differentiated CD28- CD8+ T cells and increased CD57, a marker of proliferative history. Whether chronic HIV infection causes similar effects is currently unclear.
Methods: We compared markers of CD8+ T cell differentiation (e.g., CD28, CD27, CCR7, CD45RA) and CD57 expression on CD28- CD8+ T cells in healthy HIV-uninfected adults with and without CMV infection and in both untreated and antiretroviral therapy (ART)-suppressed HIV-infected adults with asymptomatic CMV infection.
Results: Compared to HIV-uninfected adults without CMV (n = 12), those with asymptomatic CMV infection (n = 31) had a higher proportion of CD28-CD8+ T cells expressing CD57 (P = 0.005). Older age was also associated with greater proportions of CD28-CD8+ T cells expressing CD57 (rho: 0.47, P = 0.007). In contrast, untreated HIV-infected CMV+ participants (n = 55) had much lower proportions of CD28- CD8+ cells expressing CD57 than HIV-uninfected CMV+ participants (P,0.0001) and were enriched for less well-differentiated CD28- transitional memory (TTR) CD8+ T cells (P,0.0001). Chronically HIV-infected adults maintaining ART-mediated viral suppression (n = 96) had higher proportions of CD28-CD8+ T cells expressing CD57 than untreated patients (P,0.0001), but continued to have significantly lower levels than HIV-uninfected controls (P = 0.001). Among 45 HIV-infected individuals initiating their first ART regimen, the proportion of CD28-CD8+ T cells expressing CD57 declined (P,0.0001), which correlated with a decline in percent of transitional memory CD8+ T cells, and appeared to be largely explained by a decline in CD28-CD57- CD8+ T cell counts rather than an expansion of CD28-CD57+ CD8+ T cell counts.
Conclusions: Unlike CMV and aging, which are associated with terminal differentiation and proliferation of effector memory CD8+ T cells, HIV inhibits this process, expanding less well-differentiated CD28- CD8+ T cells and decreasing the proportion of CD28- CD8+ T cells that express CD57
IL-2 Immunotherapy to Recently HIV-1 Infected Adults Maintains the Numbers of IL-17 Expressing CD4+ T (TH17) Cells in the Periphery
Little is known about the manipulation of IL-17 producing CD4+ T cells (TH17) on a per-cell basis in humans in vivo. Previous studies on the effects of IL-2 on IL-17 secretion in non-HIV models have shown divergent results. We hypothesized that IL-2 would mediate changes in IL-17 levels among recently HIV-1-infected adults receiving anti-retroviral therapy. We measured cytokine T cell responses to CD3/CD28, HIV-1 Gag, and CMV pp65 stimulation, and changes in multiple CD4+ T cell subsets. Those who received IL-2 showed a robust expansion of naive and total CD4+ T cell counts and T-reg counts. However, after IL-2 treatment, the frequency of TH17 cells declined, while counts of TH17 cells did not change due to an expansion of the CD4+ naĂŻve T cell population (CD27+CD45RA+). Counts of HIV-1 Gag-specific T cells declined modestly, but CMV pp65 and CD3/CD28 stimulated populations did not change. Hence, in contrast with recent studies, our results suggest IL-2 is not a potent in vivo regulator of TH17 cell populations in HIV-1 disease. However, IL-2-mediated T-reg expansions may selectively reduce responses to certain antigen-specific populations, such as HIV-1 Gag
The relationship of TP53 R72P polymorphism to disease outcome and TP53 mutation in myelodysplastic syndromes
Nonsynonymous TP53 exon 4 single-nucleotide polymorphism (SNP), R72P, is linked to cancer and mutagen susceptibility. R72P associations with specific cancer risk, particularly hematological malignancies, have been conflicting. Myelodysplastic syndrome (MDS) with chromosome 5q deletion is characterized by erythroid hypoplasia arising from lineage-specific p53 accumulation resulting from ribosomal insufficiency. We hypothesized that apoptotically diminished R72P C-allele may influence predisposition to del(5q) MDS. Bone marrow and blood DNA was sequenced from 705 MDS cases (333 del(5q), 372 non-del(5q)) and 157 controls.
Genotype distribution did not significantly differ between del(5q) cases (12.6% CC, 38.1% CG, 49.2% GG), non-del(5q) cases (9.7% CC, 44.6% CG, 45.7% GG) and controls (7.6% CC, 37.6% CG, 54.8% GG) (P = 0.13). Allele frequency did not differ between non-del(5q) and del(5q) cases (P = 0.91) but trended towards increased C-allele frequency comparing non-del(5q) (P = 0.08) and del(5q) (P = 0.10) cases with controls. Median lenalidomide response duration increased proportionate to C-allele dosage in del(5q) patients (2.2 (CC), 1.3 (CG) and 0.89 years (GG)). Furthermore, C-allele homozygosity in del(5q) was associated with prolonged overall and progressionfree survival and non-terminal interstitial deletions that excluded 5q34, whereas G-allele homozygozity was associated with inferior
outcome and terminal deletions involving 5q34 (P = 0.05). These findings comprise the largest MDS R72P SNP analysis
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Track A Basic Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138319/1/jia218438.pd
Recommended adult immunization schedule, United States, 2020
In October 2019, the Advisory Committee on Immunization
Practices (ACIP) voted to approve the Recommended
Adult Immunization Schedule for Ages 19
Years or Older, United States, 2020. The 2020 adult immunization
schedule, available at www.cdc.gov/vaccines
/schedules/hcp/imz/adult.html, summarizes ACIP recommendations
in 2 tables and accompanying notes (Figure).
The full ACIP recommendations for each vaccine are available
at www.cdc.gov/vaccines/hcp/acip-recs/index.html.
The 2020 schedule has also been approved by the director
of the Centers for Disease Control and Prevention
(CDC) and by the American College of Physicians (www
.acponline.org), American Academy of Family Physicians
(www.aafp.org), American College of Obstetricians and
Gynecologists (www.acog.org), and American College of
Nurse-Midwives (www.midwife.org)
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