Molecular Biology and Immunology for Clinicians 24*

Individual variability among autochthonous sheep in Northern Tunisia to infection by abomasum nematodes and Babesia/Theileria parasites

In Tunisia, livestock plays an important role in the economy; unfortunately, Tunisian sheep population faces several health challenges. The aim of this trial was to study phenotypic variability of four local sheep breeds and strains to abomasum nematodes infection and to Babesia/Theileria parasites. Faeces, blood and abomasum contents were collected from 310 sheep slaughtered in eight commercial slaughterhouses across North Tunisia. Haematological and biochemical parameters were assessed. DNA was extracted and catch‐all primers were used to detect both Theileria spp. and Babesia spp. DNA. Faecal egg counts (FEC) was quantitatively assessed using simple flotation technique followed by McMaster technique. Male and female worms were collected from all abomasum contents and counted under a stereomicroscope. The percentage of faeces samples positive for GIN’s eggs was 30.82%. After worms’ recovery, the infection prevalence was estimated to 75.90%. The overall infection prevalence by Babesia spp. and Theileria spp. was 4.21%. The dispersion of observations plots obtained by principal component analysis (PCA) showed two clusters of individuals. The first cluster contains animals having positive Babesia/Theileria PCR, presence of nematodes in the abomasum contents and relatively low total worm count (TWC < 500) expect one animal which was found bearing high TWC (>500). In this same group, with a suspected form of resistance, animals showed normal values of albumin and normal haematological parameters (red blood cell count [RBC], haemoglobin [Hb] and packed cell volume [PCV]). The second cluster represents all the other observations in which subgroups of animals were distinguished on the basis of their potential resistance to abomasum nematodes. Multiple correlations showed significant positive correlations between RBC/Hb, RBC/PCV, PCV/Hb and FEC/TWC. Significant negative correlations were observed between TWC/RBC and TWC/Hb. It is concluded that the phenotypic variability among local sheep breeds is essential for more advanced genetic and genomic studies.

Increased percentage of B cells in patients with more advanced hepatocellular carcinoma

To compare immunologic phenotypes between (1) hepatocellular carcinoma (HCC) patients and a healthy population and (2) more advanced and early stage HCC patients, we studied 45 HCC patients and 46 healthy controls from January 2006 to January 2008. Using fluorescent activated cell sorter (FACS) analysis, HCC patients were demonstrated to exhibit stronger phagocytosis of granulocytes and monocytes and more peripheral blood mononuclear cells (PBMCs) in the G2/M phase compared with healthy volunteers. By contrast, lower percentages of B and T(h) lymphocytes were also found in the peripheral blood of HCC patients than in the healthy population. Most importantly, a higher percentage of B cells was found in patients with advanced HCC than in those with early HCC in terms of TNM stage (II and III vs I, p = 0.004), the Japanese Integrated Scoring system (2-3 vs 0-1, p = 0.0235), and tumor numbers (> or =2 vs 1, p = 0.005). In conclusion, our findings suggested that HCC patients might exhibit enhanced innate immunity and reduced adaptive immunity compared with healthy volunteers. A higher percentage of B cells was found in patients with more advanced HCC compared with patients with early stage HCC, which might serve as an indicator of the severity of HCC.

Basic science for the clinician 38: B cells, factories, and immunomodulators

In a previous article in this series, we explored how developing pre-T cells learn how to be well-behaved T cells that recognize and honor the "self versus nonself" dichotomy of the universe. B cells do much of the same sort of thing, with multipotent stem cells becoming committed to ultimately becoming B cells within the bone marrow and then, after judicious culling of the flock, going off to the spleen to learn the final lessons needed to become "well-behaved" B cells. Like with T cells, there are a large number of things that can, and do, go wrong. If there is a failure of the system and B cells do not develop properly, hypogammaglobulinemia may develop as a result of a number of immune deficiency syndromes that can be quite devastating. If autoreactive cells survive to emerge into the periphery, autoimmunity, either organ-specific or more global, may occur. If B cells in the periphery proliferate in an uncontrolled fashion, a variety of B cell lymphoproliferative syndromes may develop, recognizable by the phenotypic markers of their originating B cell lineage level of differentiation. The full details of how autoreactive B cells survive and thrive, only to cause disease, are not yet clear, but identification of many of the phenotypic surface markers and circulating growth factors identified to this point have borne therapeutic fruit.