Induction of a chemoattractive proinflammatory cytokine response after stimulation of keratinocytes with Propionibacterium acnes and coproporphyrin III.

BACKGROUND: The inflammation in acne vulgaris is widely thought to be induced by an immunological reaction, but the role of Propionibacterium acnes is unclear. OBJECTIVES: To examine the local host response mechanism of a keratinocyte cell line 3 h and 6 h after stimulation with viable and heat-killed P. acnes. METHODS: The quantitative expression of cytokines was measured at the mRNA level by real-time reverse transcription-polymerase chain reaction. RESULTS: The coincubation of a keratinocyte cell line with viable, but not heat-killed, P. acnes modulated an adequate cytokine response for interleukin (IL)-1beta, granulocyte/macrophage colony-stimulating factor and IL-8. High-performance liquid chromatographic analysis of the in vivo porphyrin pattern secreted by P. acnes revealed a predominance of coproporphyrin III in acne lesions. This same porphyrin fraction also modestly induced IL-8 expression by keratinocytes. CONCLUSIONS: This cytokine pattern may favour a chemotactic response and implicates P. acnes and coproporphyrin III in the recruitment of inflammatory cells to the site of infection and in the development of acne lesions.

Monoclonal antibodies against metalloporphyrins. Specificity of interaction with structurally different metalloporphyrins.

Monoclonal antibodies against Pd-coproporphyrin I have been obtained. The antibody specificity for free as well as for conjugated Pd-coproporphyrin I is characterized. Affinity constants are estimated for 3 monoclonal antibodies effectively interacting with free Pd-coproporphyrin I. A comparative study on the binding of monoclonal antibodies with analogues and derivatives of Pd-coproporphyrin I has revealed that the antigen is mainly located inside the antibody paratope. The protein adjoins complementary to the metalloporphyrin in such a manner that antibodies obtained discern only isomer I, and to some degree, isomer III of coproporphyrin.

[Fluorescent immunoanalysis. Synthesis, spectro-fluorescent and immunologic properties of conjugates of coproporphyrin I with antibodies]. / Fluorestsentni immunoanaliz. Sintez, spektral'no-fluorestsentnye i immunologicheskie svoistva kon''iugatov koproporfirina I s antitelami

The synthesis of protein conjugates with the new high-efficient fluorescent labile coproporphyrin-I was optimized. A number of conjugates of monoclonal antibodies with different coproporphyrin-I content were synthesized, and their spectral properties were studied in water and micellar solutions, i.e. adsorption, excitation and emission spectra, fluorescence quantum yields, fluorescence pH-dependences. The binding constants of coproporphyrin-I and its protein conjugates with serum albumin were determined. The antibodies labelled with coproporphyrin-I retain the functional activity and photochemically stable in water solutions. The sensitivity of fluorometric detection of coproporphyrin-I and its conjugates with proteins is more than 10 times greater than in case of FITC.