Human melanocytes can be isolated, propagated and expanded from plucked anagen hair follicles.

Herein, we report a technically simple method for isolation and culture of human follicular melanocytes based on explant cultures of epilated hair follicles. This technique does not require any surgical intervention and allows the isolation and cultivation of follicular melanocytes from a comparatively small amount of raw material. Generally, 30-60 human anagen hair follicles have been plucked from the scalp of healthy donors and cultivated under low oxygen pressure (5%). After a short period of time cells of various types were growing out from the outer root sheath (ORS) of the hair follicles. Under the selected culture conditions, most of the cells other than melanocytes have been eliminated and a nearly 100% pure population of melanocytes has been achieved, as confirmed by immunohistochemical analyses for melanocyte-specific markers, for example, Tyrosinase-1, S-100 and premelanosomal antigens. These melanocytes derived from the ORS were proliferating for up to 2 months.

Detection, isolation and partial characterization of an immunostimulating glycoprotein from Rhodococcus fascians.

In a search for novel immunostimulating substances we detected that culture supernatants of the gram-positive phytopathogenic bacterium, Rhodococcus fascians, were able to induce cytokine release (TNF(alpha)) from mouse peritoneal macrophages. Monoclonal antibodies were generated against the active principle, and were employed for its isolation and partial characterization as a high molecular (MW>100 kDa) glycoprotein. In addition, methods practicable for its biotechnological preparation and several ELISA variants for its determination were developed.

Synthetic mycoplasma-derived lipopeptide MALP-2 induces maturation and function of dendritic cells.

Dendritic cells (DC) modulate immune responses depending on the nature of the antigens. Receptors capable of discriminating these antigens on the basis of the pathogen-associated molecular patterns (PAMP) belong to the Toll-like receptor (TLR) family. The macrophage-activating lipopeptide 2 kDa (MALP-2), a synthetic lipopeptide derived from Mycoplasma fermentans, signals through TLR-2 and TLR-6. The aim of this study was to examine whether MALP-2 can modulate the functional properties of human monocyte-derived DC. The effects of this treatment were compared to those of the TLR-4 agonist lipopolysaccharide (LPS). To ensure clinical applicability, DC were generated under serum-free conditions. MALP-2 and LPS stimulation induced the expression of CD83 and increased the expressions of CD80, CD86, HLA-ABC and CD40. Furthermore, both substances decreased the endocytotic capacity of DC and induced the release of bioactive TNF-alpha and IL-10, whereas LPS additionally increased IL-12 release. Pretreatment with both substances boosted the allostimulatory capacity of DC. In a coculture with autologous lymphocytes, either MALP-2 or LPS pretreated DC induced a marked proliferation of lymphocytes, but only DC prestimulated with MALP-2 activated lymphocytes to produce the cytokines IL-4, IL-5 and IFN-gamma. No polarisation of lymphocytes into T-helper (Th)1 or Th2 was detected. These data indicate that MALP-2 is a potential candidate to modulate DC for clinical applications.