Hallwirth Ulrike, Pomberger Gerhard, Pollak Arnold, Roth Erich, Spittler Andreas
Department of Pediatric Surgery, University of Graz, Graz, Austria.
Pediatr Allergy Immunol. 2004 Dec;15(6):513-6. doi: 10.1111/j.1399-3038.2004.00168.x.
Pre-term neonates are at high risk to develop early-onset sepsis which possibly is caused by an immature immune system. Monocytes play a pivotal role as professional phagocytic and antigen-presenting cells in the innate immunity. In the present study, we investigated in monocytes from cord blood the expression of human leukocyte antigen (HLA)-DR as a marker for antigen-presenting capability, the expression of the high-affinity receptor for IgG (FcgammaRI/CD64), and the capacity to phagocytize non-opsonized Escherichia coli. We compared 70 infants in three groups according to their gestational age (group I: 20 very low birth weight infants (VLBWI), 24-31 weeks of gestation; group II: 25 pre-term infants, 32-36 weeks of gestation, and group III: 25 term neonates). The expression of CD64 as well as the phagocytic capacity of monocytes from cord blood were highest in VLBWI (p < 0.05 and p < 0.01, respectively). In contrast, HLA-DR expression was significantly (p < 0.05) diminished in VLBWI, which possibly leads to a reduced antigen-presenting capacity. We conclude that monocytes have different functional properties during gestational aging, which perhaps participate in the high incidence of infections in VLBWI.
早产儿发生早发性败血症的风险很高，这可能是由不成熟的免疫系统引起的。单核细胞作为先天性免疫中专业的吞噬细胞和抗原呈递细胞发挥着关键作用。在本研究中，我们研究了脐血单核细胞中人白细胞抗原（HLA）-DR作为抗原呈递能力标志物的表达、IgG高亲和力受体（FcγRI/CD64）的表达以及吞噬未调理的大肠杆菌的能力。我们根据胎龄将70名婴儿分为三组（第一组：20名极低出生体重婴儿（VLBWI），胎龄24 - 31周；第二组：25名早产儿，胎龄32 - 36周；第三组：25名足月儿）。脐血单核细胞中CD64的表达以及吞噬能力在极低出生体重婴儿中最高（分别为p < 0.05和p < 0.01）。相比之下，极低出生体重婴儿中HLA - DR的表达显著降低（p < 0.05），这可能导致抗原呈递能力下降。我们得出结论，单核细胞在孕期具有不同的功能特性，这可能参与了极低出生体重婴儿感染的高发生率。
