02787nas a2200409   4500000000100000008004100001260001600042653002000058653001400078653001800092653001200110653002300122653002400145653002400169653002400193653000900217653001200226653001200238653001100250653004000261653001800301653003000319653002500349653002100374653002800395653003100423100001400454700000900468700001600477700001800493700001700511245012200528300001200650490000700662520169400669022001402363       1999                            d  c1999 Aug 1710aCells, Cultured10aCell Wall10aBase Sequence10aAnimals10aSurface Properties10aAmino Acid Sequence10aAdhesins, Bacterial10aMice, Inbred BALB C10aMice10aleprosy10aLaminin10aHumans10aElectrophoresis, Polyacrylamide Gel10aSchwann Cells10aPeripheral Nervous System10aMycobacterium leprae10aMolecular Weight10aMolecular Sequence Data10aMicroscopy, Immunoelectron1 aShimoji Y1 aNg V1 aMatsumura K1 aFischetti V A1 aRambukkana A00aA 21-kDa surface protein of Mycobacterium leprae binds peripheral nerve laminin-2 and mediates Schwann cell invasion.  a9857-620 v963 a<p>Nerve damage is the hallmark of Mycobacterium leprae infection, which results from M. leprae invasion of the Schwann cell of the peripheral nervous system. We have recently shown that the laminin-2 isoform, specially the G domain of laminin alpha2 chain, on the Schwann cell-axon unit serves as an initial neural target for M. leprae. However, M. leprae surface molecules that mediate bacterial invasion of peripheral nerves are entirely unknown. By using human alpha2 laminins as a probe, a major 28-kDa protein in the M. leprae cell wall fraction that binds alpha2 laminins was identified. After N-terminal amino acid sequence analysis, PCR-based strategy was used to clone the gene that encodes this protein. Deduced amino acid sequence of this M. leprae laminin-binding protein predicts a 21-kDa molecule (ML-LBP21), which is smaller than the observed molecular size in SDS/PAGE. Immunofluorescence and immunoelectron microscopy on intact M. leprae with mAbs against recombinant (r) ML-LBP21 revealed that the protein is surface exposed. rML-LBP21 avidly bound to alpha2 laminins, the rG domain of the laminin-alpha2 chain, and the native peripheral nerve laminin-2. The role of ML-LBP21 in Schwann cell adhesion and invasion was investigated by using fluorescent polystyrene beads coated with rML-LBP21. Although beads coated with rML-LBP21 alone specifically adhered to and were ingested by primary Schwann cells, these functions were significantly enhanced when beads were preincubated with exogenous alpha2 laminins. Taken together, the present data suggest that ML-LBP21 may function as a critical surface adhesin that facilitates the entry of M. leprae into Schwann cells.</p>  a0027-8424