The human natural killer gene complex (NKC) encodes for numerous C-type lectin-like receptors (CTLR), which are expressed on various immune cells including natural killer (NK) cells and myeloid cells. Certain activation-induced, NKC-encoded CTLR are grouped into the C-type lectin domain family 2 (CLEC2 family) which, in humans, comprises AICL (CLEC2B), CD69 (CLEC2C), and LLT1 (CLEC2D). In this paper, we characterize a novel member of the CLEC2 family, the human orphan gene CLEC2A. The C-type lectin-like domain (CTLD) of CLEC2A is most similar to the CTLD of LLT1 ( approximately 60% similarity). Like mouse CLEC2 family members Clr-b and Clr-g, CLEC2A lacks two highly conserved cysteines (Cys4 and Cys5), which form an intramolecular bond in the CTLD of most CTLR. Alternative splicing of exon 2 and of two distinct terminal exons (exon 5A/B), respectively, gives rise to four CLEC2A variants differing in the usage of the transmembrane domain and/or in the carboxyterminal portion of the CTLD. CLEC2A transcripts were detected primarily in myeloid cell lines, but not in epithelial cell lines. In tissues, CLEC2A is selectively expressed in the skin and, at lower abundance, in hematopoietic and gonadal tissues. Finally, we show that the CLEC2A1 variant is readily expressed at the cell surface, where it may serve as a ligand for NKC-encoded NK receptors.

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Eight different batches of intravenous immunoglobulin from 3 different manufacturers were tested for neutralizing activities against all currently known streptococcal superantigens. Statistically significant variation among different intravenous immunoglobulin preparations (P<.0001) and between individual streptococcal superantigens (P<.0001) was observed. These results might be helpful for optimizing the type and dose of intravenous immunoglobulin used in adjunctive therapy for severe invasive streptococcal disease.

To evaluate the health promoting attributes of fruits and their compounds the New Zealand Institute for Plant & Food Research Ltd (PFR) is using exercise as a model for oxidative stress and immune depression. Regular exercise has health benefits believed to be derived from adaptive responses to moderate oxidative stress. However, following exhaustive or unaccustomed exercise, excessive and prolonged oxidative stress and inflammation can be detrimental and the right balance of modulation from nutritional support via fruit phytochemicals (and vitamins) may prevent damage, aid recovery, and/or enhance muscular and immune function. We have developed a research platform to evaluate physical health, performance and recovery to position new fruit varieties in this area. Utilising compositional analysis of fruit extracts, in vitro screening of muscle cells, electrically stimulated muscle ex vivo, and animal and human intervention and exercise trials, we are evaluating the physical health-promoting effects of polyphenolic phytochemicals derived from fruit, particularly berry fruits. Our research demonstrates that certain fruits may complement the benefits of regular exercise through appropriate modulation of excessive oxidative stress and inflammation.