The B-cell superantigen Finegoldia magna protein L causes pulmonary inflammation by a mechanism dependent on MyD88 but not B cells or immunoglobulins.

OBJECTIVE AND DESIGN: To determine whether Finegoldia magna protein L (PL) causes lung inflammation and, if so, whether the response is dependent on its immunoglobulin (Ig)-binding B-cell superantigenic property. MATERIAL: Pulmonary inflammatory reactions were analyzed at various time points after intratracheal administration of PL to various strains of mice. RESULTS: PL caused peribronchial and perivascular inflammation that peaked at 18-24 h. Polymorphonuclear cells (PMNs) began to accumulate in bronchoalveolar lavage fluid (BALF) of PL-challenged mice by 4 h and accounted for >90% of leukocytes by 18-24 h. Inflammation was marked by the appearance of MIP-2, KC, TNF-α, and IL-6 in the BALF with peak levels attained 4 h after PL administration. PL-induced pulmonary inflammation was associated with increased airway hyper-reactivity following inhalation of methacholine. The inflammatory reaction was unabated in mice lacking B cells and immunoglobulins. In contrast, PL-induced inflammation was abrogated in MyD88-deficient mice. PL-induced responses required alveolar macrophages. CONCLUSIONS: These results strongly suggest that PL-induced lung inflammation is dependent on an innate MyD88-dependent pathway rather than the Ig-binding properties of this microbial B cell superantigen. We propose that this pulmonary inflammatory reaction is caused by the interaction of PL with a Toll-like receptor expressed on alveolar macrophages.

Analysis of mitochondrial D-loop region casts new light on domestic water buffalo (Bubalus bubalis) phylogeny.

The phylogeny of water buffaloes (Bubalus bubalis) is still a matter of discussion, especially if the two types of domestic water buffalo (swamp and river) derived from different domestication events or if they are products of human selection. To obtain more insight, we analyzed the entire mitochondrial D-loop region of 80 water buffaloes of four different breeds, i.e., 19 swamp buffaloes (Carabao) and 61 river buffaloes (Murrah, Jafarabadi, and Mediterranean), sampled in Brazil and Italy. We detected 36 mitochondrial haplotypes with 128 polymorphic sites. Pooled with published data of South-East Asian and Australian water buffaloes and based on comprehensive median-joining network and population demography analyses we show evidence that both river and swamp buffaloes decent from one domestication event, probably in the Indian subcontinent. However, the today swamp buffaloes have an unravelled mitochondrial history, which can be explained by introgression of wild water buffalo mtDNA into domestic stocks. We are also discussing indications for an independent domestication of buffaloes in China.