Treatment of mice with the anticoccidial drug Toltrazuril does not interfere with the development of a specific cellular intestinal immune response to Eimeria falciformis

Immunity against Eimeria-infections is highly specific and it depends on cell-mediated effector mechanisms. Infections of BALB/c mice with 1000 sporulated oocysts of Eimeria falciformis led to protection against challenge infections. Treatment with the anticoccidium Toltrazuril, during primary infection, terminated the ongoing disease and did not interfere with the establishment of protective immunity against challenge infections. Mesenteric lymph node cells of infected, treated as well as non-treated and challenged BALB/c mice, showed a similar proliferation upon stimulation with parasite antigen. In contrast, neither cells of the Peyers patches, intraepithelial lymphocytes, nor spleen cells responded to stimulation with parasite antigens. Cells from all compartments and of all investigated groups proliferated and released the cytokines IFN- and IL-4 in response to the mitogen Concanavalin A. The number of cells releasing IFN- or IL-4 was not dependent on the status of infection or previous treatment with Toltrazuril. The serum IgG response against total sporozoite antigens of individual mice showed that in addition, a systemic humoral response developed in infected mice, independent of a previous drug treatment, although the specific IgG antibody concentration was higher in non-treated mice. Thus, Toltrazuril does not impair the parasite specific intestinal cellular and systemic antibody response and does not prevent the development of protection against challenge infection.     

Maximum forces applied to the orbital floor after fractures

ABSTRACT: The objective of this study was to measure the force on and displacement of completely detached intraorbital tissue from thebony orbit, as a worst-case scenario after orbital trauma, to preserve the maximum load and predict the necessary strength of reconstruction materials. Six fresh-frozen human heads were used, and orbital floor defects in the right and left orbits were created by the direct impact of 3.0 J onto the globe and infraorbital rim. The orbital floor defect sizes and displacements were evaluated after performing a Le Fort I osteotomy. In addition, after the repositioning of the completely detached intraorbital tissue, the forces and displacements were measured. The mean orbital floor defect sizes were 208.3 (SD, 33.4) mm for globe impacts and 221.8 (SD, 53.1) mm for infraorbital impacts. The mean intraorbital tissue displacement after the impact and before repositioning was 5.6 (SD, 1.0) mm for globe impacts and 2.8 (SD, 0.7) mm for infraorbital impacts. After repositioning, the displacements were 0.8 (SD, 0.5) mm and 1.1 (SD, 0.7) mm, respectively. The measured forces were 0.10519 (SD, 0.00958) N without the incorporation and approximately 0.11128 (SD, 0.003599) N with the incorporation of reconstruction materials. The maximum forces on the completely detached orbital tissue were minimal (～0.11 N) and suggest the use of collagen membranes as reconstruction materials for orbital floor defects, at least in medium-sized fractures.     

Morphologic Studies in a Recently Described Dyserythropoietic State

Studies of fetal hemoglobin and bonemarrow ultrastructure were performedon a patient with a recently describedsyndrome consisting of lymphosarcoma, short stature, defective cellularimmunity, hypogammaglobulinemia,and mosaicism for a marker chromosome. Abnormalities of the erythroidcells, including multinucleated erythroblasts, nuclear bodies, megaloblasts,and frayed cytoplasm, were seen bylight microscopy. Ultrastructure confirmed the findings by light microscopy and showed in greater detailnuclear malformation, loss of nuclearmembrane, and loss of cytoplasmicbackground, as well as peculiar cytoplasmic inclusions. An increased levelof fetal hemoglobin (Hb F), rangingbetween 12%-15%, was detected. TheHb F was discreetly distributed, occurring in a small per cent of the redblood cells. It is speculated that aclone of chromosomally abnormalerythroid precursors might be responsible for producing the erythroblastswith the structural abnormalitiesdescribed and the erythrocytes withthe high hemoglobin F content.

Submitted on February 11, 1972 Revised on April 18, 1972 Accepted on May 10, 1972     

Dimethylfumarate inhibits microglial and astrocytic inflammation by suppressing the synthesis of nitric oxide,IL-1β, TNF-α and IL-6 in an in-vitro model of brain inflammation

Background  

Brain inflammation plays a central role in multiple sclerosis (MS). Dimethylfumarate (DMF), the main ingredient of an oral formulation of fumaric acid esters with proven therapeutic efficacy in psoriasis, has recently been found to ameliorate the course of relapsing-remitting MS. Glial cells are the effector cells of neuroinflammation; however, little is known of the effect of DMF on microglia and astrocytes. The purpose of this study was to use an established in vitro model of brain inflammation to determine if DMF modulates the release of neurotoxic molecules from microglia and astrocytes, thus inhibiting glial inflammation.     

Attempts to establish RNA interference in the parasitic nematode Heligmosomoides polygyrus

To analyze the potential of RNA interference (RNAi) in the intestinal nematode Heligmosomoides polygyrus, we delivered double-stranded RNA (dsRNA) of tropomyosin to various life stages of the parasite. Three different methods were examined for their potential use. First, feeding of recombinant bacteria that expressed dsRNA did neither result in phenotypical changes of H. polygyrus nor in a significant reduction of tropomyosin mRNA levels. In contrast, feeding of such bacteria to Caenorhabditis elegans elicited the expected phenotypes. Quantification of bacteria ingested by C. elegans and H. polygyrus larvae (L1) revealed that the parasitic worms took up only a fraction of the bacteria ingested by C. elegans. Second, electroporation of L1 failed to transport siRNA through the cuticle and was lethal to the larvae. However, the cuticle of adult worms was penetrated by dye-labeled RNA, but no systemic spreading was observed. Third, soaking of adult H. polygyrus in tropomyosin dsRNA led to a higher proportion of worms showing symptoms of ageing, such as a disintegrated gut and ovaries, but did not induce reduction of tropomyosin mRNA levels. Database analysis revealed that orthologous proteins involved in dsRNA-uptake and -systemic spread in C. elegans are missing in the parasitic nematodes Brugia malayi and Haemonchus contortus, whereas proteins responsible for dsRNA-processing, -amplification and mRNA-regulation are present. Thus, our data indicate that the study of gene function by RNAi in H. polygyrus is limited, possibly due to deficiencies of genes involved in RNA-uptake and spread.     

Chemokine expression in the white matter spinal cord precursor niche after force‐defined spinal cord contusion injuries in adult rats

Inflammatory cascades induced by spinal cord injuries (SCI) are localized in the white matter, a recognized neural stem‐ and progenitor‐cell (NSPC) niche of the adult spinal cord. Chemokines, as integrators of these processes, might also be important determinants of this NSPC niche. CCL3/CCR1, CCL2/CCR2, and SDF‐1α/CXCR4 were analyzed in the ventrolateral white matter after force defined thoracic SCI: Immunoreactivity (IR) density levels were measured 2 d, 7 d, 14 d, and 42 d on cervical (C 5), thoracic (T 5), and lumbar (L 5) levels. On day post operation (DPO) 42, chemokine inductions were further evaluated by real‐time RT‐PCR and Western blot analyses. Cellular phenotypes were confirmed by double labeling with markers for major cell types and NSPCs (nestin, Musashi‐1, NG2, 3CB2, BLBP). Mitotic profiles were investigated in parallel by BrdU labeling. After lesion, chemokines were induced in the ventrolateral white matter on IR‐, mRNA‐, and protein‐level. IR was generally more pronounced after severe lesions, with soaring increases of CCL2/CCR2 and continuous elevations of CCL3/CCR1. SDF‐1α and CXCR4 IR induction was focused on thoracic levels. Chemokines/‐receptors were co‐expressed with astroglial, oligodendroglial markers, nestin, 3CB2 and BLBP by cells morphologically resembling radial glia on DPO 7 to DPO 42, and NG2 or Musashi‐1 on DPO 2 and 7. In the white matter BrdU positive cells were significantly elevated after lesion compared with sham controls on all investigated time points peaking in the early time course on thoracic level: Here, chemokines were co‐expressed by subsets of BrdU‐labeled cells. These findings suggest an important role of chemokines/‐receptors in the subpial white matter NSPC niche after SCI. © 2010 Wiley‐Liss, Inc.     

Internalization and signal transduction of PrP106−126 in neuronal cells

Invasion of the nervous system and neuronal spread of infection are critical, but poorly understood steps in the pathogenesis of prion diseases. We have thus analyzed the internalization and signal transduction of the neurotoxic fragment of the prion protein PrP_106–126 in the rat neuroblastoma cell line B104 by fluorescence microscopy and quantification by ELISA and in primary neuronal cells from mice. Phospholipase D (PLD) is known to be an enzyme involved in the regulation of secretion, endocytosis and receptor signalling. We determined the PLD activity using a transphosphatidylation assay and could show that PLD is involved in PrP_106–126 internalization. The determination of receptor activity via quantification of ERK1/2 phosphorylation and cAMP level measurement verified the PrP_106–126-induced signal transduction in B104 cells and primary neuronal cells. PrP_106−126-induced a decrease in cAMP level in neuronal cells. These studies indicate the involvement of PLD in PrP_106–126-endocytosis and mediated cellular signalling by an unidentified inhibitory G-protein-coupled receptor and may allow the development of therapeutic agents interfering with prion uptake and/or PLD function using PLD as a possible pharmaceutical target.