Burrells C
Vet Immunol Immunopathol. 1985 Nov;10(2-3):225-43. doi: 10.1016/0165-2427(85)90049-2.
Bronchoalveolar washings were harvested from the excised lungs of 68 normal sheep of 3 different age groups (A: birth to 8 weeks; B: 6 months to 2 years; C: older than 2 years). Cells and fluid obtained were examined quantitatively and functionally. Fewer cells were present in the lavage fluids of Group A sheep compared with those of Groups B and C. Macrophages were the predominant cell type (70-80%) in all sheep, with lymphocytes being second in number. The lower proportion of lymphocytes in young sheep (Group A) was attributable to lack of B-lymphocytes. As a proportion of the lymphocyte population T-cells were in the majority (60-80%) in all sheep. The proportion of null cells was higher in young sheep than in adults. Pulmonary lymphocytes from sheep of all ages responded poorly to stimulation by the non-specific mitogens phytohaemagglutinin, concanavalin A, pokeweed mitogen and lipopolysaccharide of Escherichia coli. The proportion of neutrophils was higher in sheep over 2 years old compared with younger animals. Eosinophils were present in all age groups but their proportion was greatly increased in animals over 2 years of age. Basophils were absent in young sheep and were present in only low numbers in the lungs of adult animals. In young sheep (Group A) IgG was the predominant immunoglobulin. With age, the percentage of IgG in lung fluid decreased while that of IgA increased so that IgA became the predominant immunoglobulin in older animals (Group C). In sheep of all ages IgM was present in negligible amounts. The highest value of complement (C3) occurred in adult sheep (Group B). The total white blood cell counts and differential blood counts of all the sheep were within accepted normal ranges. As in the lungs, there was an age-associated reduction in the proportions of blood T-lymphocytes and an increase in B-lymphocytes. In contrast to lung lymphocytes, those from the blood of sheep of all ages exhibited a wide range of responses to mitogens. The lowest stimulation indices were observed in the oldest sheep (Group C). The results provide background data against which assessment can be made of changes consequent upon infection with respiratory pathogens.
从3个不同年龄组（A组：出生至8周；B组：6个月至2岁；C组：2岁以上）的68只正常绵羊的离体肺中采集支气管肺泡灌洗液。对获得的细胞和液体进行定量和功能检查。与B组和C组绵羊相比，A组绵羊灌洗液中的细胞较少。巨噬细胞是所有绵羊中主要的细胞类型（70 - 80%），淋巴细胞数量次之。幼羊（A组）中淋巴细胞比例较低是由于缺乏B淋巴细胞。作为淋巴细胞群体的一部分，T细胞在所有绵羊中占多数（60 - 80%）。幼羊中裸细胞的比例高于成年羊。所有年龄绵羊的肺淋巴细胞对非特异性有丝分裂原植物血凝素、刀豆球蛋白A、商陆有丝分裂原和大肠杆菌脂多糖的刺激反应较差。2岁以上绵羊中性粒细胞的比例高于年幼动物。所有年龄组均有嗜酸性粒细胞，但在2岁以上动物中其比例大幅增加。幼羊中无嗜碱性粒细胞，成年动物肺中嗜碱性粒细胞数量也很少。在幼羊（A组）中，IgG是主要的免疫球蛋白。随着年龄增长，肺液中IgG的百分比下降，而IgA的百分比增加，因此在年长动物（C组）中IgA成为主要的免疫球蛋白。在所有年龄的绵羊中，IgM的含量可忽略不计。补体（C3）的最高值出现在成年绵羊（B组）中。所有绵羊的白细胞总数和分类计数均在公认的正常范围内。与肺中情况一样，血液中T淋巴细胞的比例随年龄增长而降低，B淋巴细胞的比例则增加。与肺淋巴细胞不同，所有年龄绵羊血液中的淋巴细胞对有丝分裂原表现出广泛的反应。在最年长的绵羊（C组）中观察到最低的刺激指数。这些结果提供了背景数据，可据此评估呼吸道病原体感染后的变化。
