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Lakshmi Jayashankar Kathleen M. Brasky John A. Ward Roberta Attanasio 《Clinical and Vaccine Immunology : CVI》2003,10(5):870-875
The age-related modulation of lymphocyte number and function was assessed in a nonhuman primate model consisting of healthy olive baboons (Papio cynocephalus anubis) of ages encompassing the entire life span of this species. The objectives of this study were to characterize an animal model of immunosenescence and to assess whether or not age should be considered when designing studies for the evaluation of vaccine candidates in baboons. Specifically the following parameters were assessed in baboons from 6 months to 26 years of age: relative numbers of B lymphocytes, CD4+ and CD8+ T lymphocytes, and T lymphocytes expressing CD28, CD25, and phytohemagglutinin-stimulated lymphoproliferative activity; and concentrations of total immunoglobulin, soluble interleukin-2 receptor α, and soluble CD30 in serum. There was a statistically significant effect of age on lymphocyte numbers. As age increased, relative B-cell numbers (ranging from 6 to 50%) decreased (P < 0.001) and relative T-cell numbers (ranging from 28 to 80%) increased (P < 0.001). The increase in T-cell numbers involved both the CD4+ and CD8+ subsets. In addition, there was a significant negative correlation of age with levels of soluble interleukin-2 receptor α in serum. Modulation of lymphocyte numbers appears to occur gradually during the entire baboon life span, thus suggesting the presence of an age-related developmentally regulated process. These findings indicate that baboons represent a potentially useful model to study selected phenomena related to immunosenescence. These findings also indicate that, when using the baboon model for vaccine or other experimental protocols requiring the assessment of immune responses, it would be appropriate to take into account the age of the animals in the study design. 相似文献
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Bals-Pratsch M; De Geyter C; Muller T; Frieling U; Lerchl A; Pirke KM; Hanker JP; Becker-Carus C; Nieschlag E 《Human reproduction (Oxford, England)》1997,12(5):896-904
Preliminary data have suggested that female infertility due to corpus
luteum insufficiency may be caused by subclinical hypothyroidism
[exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin-
releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been
recommended to achieve pregnancies in subclinical hypothyroid women. This
controlled study was carried out in order to investigate the biochemical
diagnosis of subclinical hypothyroidism as a possible infertility factor.
Five infertile patients (aged 25-36 years) with subclinical hypothyroidism
(n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1)
and five healthy controls (aged 22-39 years) with normal thyroid function
(stimulated TSH <15 microU/ml), regular cycles and no history of
infertility were studied in the early follicular phase. In the pre-study
evaluation, eight of 23 volunteers (34.8%) had to be excluded because of
subclinical hypothyroidism with stimulated TSH values (TSHs) >15
microU/ml. Cycle function of patients and controls was compared by the
method of LH pulse pattern analysis. Therefore blood samples were drawn
every 10 min during a 24 h period. Sleep was recorded from midnight to 7
a.m. Repetition of the TRH tests at the end of the 24 h blood sampling
period confirmed the difference in stimulated TSH values of the two study
groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin
showed no differences between patients and controls for pulse frequency,
amplitude, height, length, area under curve (AUC) and the 24 h mean. Even
the hypothyroid patient had a normal LH pulse pattern. Additional
measurement of melatonin in pooled sera every 30 min gave the
well-documented diurnal profiles during day and night for both groups.
Patients had significantly higher melatonin values at seven time points
during the night. Peaks for LH, TSH, prolactin and cortisol were correlated
with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We
concluded that corpus luteum insufficiency in female infertility cannot be
explained by subclinical hypothyroidism and thus should not be treated with
L-thyroxine for fertility reasons.
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