Giardia lamblia is an important cause of parasitic diarrheal disease worldwide. Occasionally, polymorphonuclear neutrophils (PMNs) may participate as effector cells against
Giardia lamblia. The ...present study was performed in order to examine the role of specific antibody and complement components in promoting the respiratory burst (RB) of PMNs against
Giardia lamblia.
PMNs from human adult volunteers were incubated with
Giardia trophozoites in the presence of non-immune (NS) or hyperimmune (HS) serum (anti-
Giardia titer, >1:1024). Adherence was scored visually on coverslide after staining with Giemsa. The ability of
Giardia to trigger the oxidative response of PMNs was measured by the anion superoxide (O
2
−) production using a cytochrome C reduction method and by the luminol amplified chemiluminescence (CL) assay.
Incubation with NS or HS increased
Giardia adherence to PMNs from 6.9 ± 3.2% (basal adherence of
Giardia incubated in buffer) to 39 ± 18.6% (
p <0.01) and 76 ± 19.5% (
p <0.001), repectively. In absence of serum,
Giardia failed to trigger an oxidative response of PMNs. Opsonization with NS or HS increased the PMN O
2
− production from 3.9 ± 0.92 nmol/2.5 × 10
6 PMNs/10 min to 9.04 ± 1.68 (
p <0.05) and 17.9 ± 1.32 (
p <0.001), respectively. A similar enhancement of the CL response was also observed. The inactivation of complement activity by heat as well as the elimination of specific antibodies by absorption produced a significant abrogation of the oxidative response but in the case of HS heat inactivation alone did not abolish the response. Similar findings (variable abrogation of the oxidative PMN response) were observed when PMNs were incubated with monoclonal antibodies directed against complement C3, C3b or the low-affinity Fc receptors (CR1, CR3 or FcRlo).
These results show that complement components and specific antibodies influence in the
Giardia–PMN interaction. Although components of complement can contribute to the RB of PMNs, specific antibodies are critical for an optimal oxidative PMN response.
The on-demand provisioning of network and computing resources from cloud to edge in novel connected mobility use cases presents challenges related to the management of heterogeneous, distributed ...devices, dynamic quality of service (QoS) requirements, security and privacy concerns, multi-access coordination and control, integration of 5G and future 6G networks, among others. The ONOFRE-3 project presents a comprehensive architecture for enabling on-demand provisioning of network and computing resources from cloud to edge in con-nected mobility scenarios. ONOFRE-3 addresses the challenges of managing diverse devices across edge, fog, and cloud by leveraging artificial intelligence (AI) and machine learning (ML) techniques for dynamic QoS monitoring and orchestration, as well as dis-tributed and federated learning paradigms to empower secure distributed applications across the cloud computing continuum and among peer domains. The architecture features mechanisms for core and network infrastructure planning, online resource provisioning, management of multiple radio access technologies, and computation offloading. Security trust zone capabilities are enhanced through analytics-based proactive actions and network slicing isolation. ONOFRE-3 also includes two complementary testbeds and a simulation platform, where partial evaluations of selected architecture features have been carried out.
Archaeology of Southern Mesoamerica comprises the second and third volumes in the Handbook of Middle American Indians, published in cooperation with the Middle American Research Institute of Tulane ...University under the general editorship of Robert Wauchope (1909–1979). The volume editor is Gordon R. Willey (1913–2002), Bowditch Professor of Mexican and Central American Archaeology and Ethnology at Harvard University. Volumes Two and Three, with more than 700 illustrations, contain archaeological syntheses, followed by special articles on settlement patterns, architecture, funerary practices, ceramics, artifacts, sculpture, painting, figurines, jades, textiles, minor arts, calendars, hieroglyphic writing, and native societies at the time of the Spanish conquest of the Guatemala highlands, the southern Maya lowlands, the Pacific coast of Guatemala, Chiapas, the upper Grijalva basin, southern Veracruz, Tabasco, and Oaxaca. The Handbook of Middle American Indians was assembled and edited at the Middle American Research Institute of Tulane University with the assistance of grants from the National Science Foundation and under the sponsorship of the National Research Council Committee on Latin American Anthropology.
