The complement system participates in the immune recognition of foreign antigens, many of which may penetrate the skin by physical injury or transcutaneous adsorption. In this study, we examined the presence of complement components and complement regulatory proteins in the human skin and cultured human keratinocytes. Immunofluorescence studies showed C3, Factor B, decay accelerating factor, the C3b receptor (CR1), and C3d receptor (CR2), distributed among cells of the epidermis as well as on cultured keratinocytes. Immunoblot analysis of keratinocytes supernatants showed the presence ofC3 with a molecular weight of 180 kD. The decay accelerating factor was localized as previously reported on elastic fibers; additionally it was observed in the basement membrane zone. In situ hybridization studies suggest the expression of CR1 and CR2 mRNA in human epidermis. These results show the presence in the human epidermis of complement components that are capable of generating the initial C3 convertase of the alternative pathway. The presence of complement regulatory proteins could endow keratinocytes with immune functions such as the regulation of complement activation and endocytosis of C3 opsonized parti-

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Invertases are glycosidases applied for synthesis of alkyl glycosides that are important and effective surfactants. Stability of invertases in the environment with increased content of organic solvent is crucial for increase of productivity of glycosidases. Their stability is significantly influenced by N-glycosylation. However, yeast N-glycosylation pathways may synthesize plethora of N-glycan structures. A total natural crude mixture of invertase glycoforms (EINV) extracted from Saccharomyces cerevisiae was subfractionated by anionexchange chromatography on industrial monolithic supports to obtain different glycoforms (EINV1-EINV3). Separated glycoforms exhibited different stabilities in water-alcohol solutions that are in direct correlation with the amount of phosphate bound to N-glycans.Observed differences in stability of different invertase glycoforms were used to improve productivity of methyl β-D-fructofuranoside (MF) synthesis. The efficiency and yield of MF synthesis was improved more than 50% when the most stabile glycoform bearing the lowest amount of phosphorylated N-glycans is selected and utilized. These data underline the importance of analysis of glycan structures attached to glycoproteins, demonstrates different impact of N-glycans on the surface charge and enzyme stability in regard to particular reaction environment, and provide a platform for improvement of yield of industrial enzymatic synthesis by chromatographic selection of glycoforms on monolithic supports.

An unusual triclonal IgG combination in the serum of a 56‐year old male with clinical stage IIIB multiple myeloma is reported. The patient initially had an IgG4(Λ) monoclonal protein in his serum and later developed an IgG2(κ) and an IgG (κ) which possessed the characteristics of both IgG1 and IgG3 subclasses with an unusual combination of allotypic markers. Three M‐proteins did not share idiotypic determinants. A rare class‐switch recombination followed by mutation has been considered as a possible mechanism leading to this combination.

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