Raida K. Al-Rukibat

Investigation of the role of tumour necrosis factor-α, interleukin-1β, interleukin-10, nitric oxide and rheumatoid factor-immunoglobulin M in a rat model of arthritis

Collagen-induced arthritis (CIA) in rats is a widely used preclinical animal model of rheumatoid arthritis (RA). However, CIA development in Sprague-Dawley (SD) rats is less severe in terms of inflammatory response compared with other strains. Therefore, a modified CIA model called MCIA, using N-acetylmuramyl dipeptide (MDP), has been developed in the less sensitive SD rat strains. This work was conducted to better understand the immunopathological role and contributions of the pro-inflammatory T-helper type 1 (Th-1) cytokines and inflammatory mediators, interleukin-1 (IL-1β), tumour necrosis factor-alpha (TNF-α) and nitric oxide (NO); the anti-inflammatory T-helper type 2 (Th-2) cytokine, IL-10 and autoantibodies such as rheumatoid factor (RF)-immunoglobulin M (IgM) in this newly developed RA model. TNF-α, NO and RF-IgM levels were significantly increased, while IL-1β levels were not affected in this MCIA rat model. The levels of IL-10 were lower than the baseline when compared with controls. In conclusion: (1) the immunological features represented in the MCIA rat model favour the Th-1 cytokine profile over Th-2 and (2) RF-IgM can be used as a diagnostic test in preclinical RA models.

Distribution and density of mast cells in camel small intestine and influence of fixation techniques

This study was carried out to gather species-specific data on mast-cell density and distribution in camel small intestine under different fixation conditions and to elucidate the presence and cross-reactivity of tryptase in the camel small intestine using human specific anti-tryptase antibody. Tissue specimens from the jejunum, duodenum, and ileum were obtained from 9 healthy, 9-12 months old, male camels. Specimens were fixed either with carnoys fluid or formalinbuffered solution and stained with either methylene blue or immunohistochemically to identify mast cells. The present study demonstrated for the first time, the presence and cross-reactivity of tryptase in the camel small intestine using a specific mouse anti-human tryptase antibody. Mast cells were detected in all histological layers of the camel small intestine (mucosal, submucosal, muscularis externa and serosa). Among all locations examined in the duodenum, ileum and jejunum, no significant difference was observed in mast-cell counts among the lamina propria, muscularis mucosae, muscularis externa and the serosa. The only significant difference observed was the mast-cell count in submucosa region where the highest and lowest mast count was observed in the jejenual and ileal submucosa, respectively. Significant differences regarding the distribution of mast cell as well as the influence of the fixation method could be observed. This underlines the fact that data regarding mast cell heterogeneity from other species, obtained by different fixation methods, are not comparable. This fact has to be taken into account when evaluating mast cell subtypes under pathological conditions.

What is your diagnosis? Lymphoadenopathy in a cow

A 4-year-old Holstein Friesian cow was presented to the Veterinary Health Center, Faculty of Veterinary Medicine at Jordan University of Science and Technology with the primary complaint of lethargy, inappetence, and reduced milk production for 2-week duration. On physical examination, the cow was febrile and lethargic, the mucous membranes were pale and the respiratory rate was increased. Many of the subcutaneous lymph nodes were enlarged. Smears were prepared from a fine-needle aspirate of the prescapular lymph nodes and submitted for cytologic examination (Figure 1, 2). Peripheral blood was collected from the jugular vein and submitted for a CBC including differential counts. Erythrogram changes showed mild macrocytic normochromic anemia. Leukogram changes showed mild leukopenia and neutropenia. A thrombocytopenia was also present. Smears of peripheral blood were also examined under the microscope for evaluation of cell morphology. Figure 2. Fine-needle aspiration smear from enlarged prescapular lymph node of a cow. Diff-3 stain, Bar = 10 lm. Figure 1. Fine-needle aspiration smear from enlarged prescapular lymph node of a cow. Diff-3 stain, Bar = 10 lm.