Prenatal immune priming in onchocerciasis—Onchocerca volvulus-specific cellular responsiveness and cytokine production in newborns from infected mothers

This study investigated the effect of maternal Onchocerca volvulus infection on humoral and cellular responsiveness in newborn children and their mothers. Onchocerca volvulus-specific IgG isotypes and IgE were significantly elevated in infected mothers and their infants. One year post partum, O. volvulus-specific IgG4 was strongly reduced in children of infected mothers, while IgG1 responses weakened only slightly. Umbilical cord mononuclear blood cells (UCBC) and peripheral blood cells (PBMC) from mothers proliferated in response to phytohaemagglutinin (PHA), concanavalin A (Con A), and the bacterial antigens streptolysin-O (SL-O) or purified protein derivative (PPD). UCBC from neonates born to O. volvulus-infected mothers responded lower (P < 0.01) to Con A (at 5 μg/ml), PPD (at 10 and 50 μg/ml) and O. volvulus-derived antigens (OvAg) (at 35 μg/ml), and in parallel, a diminished cellular reactivity (P < 0.01) by PBMC was observed to OvAg in mothers positive for O. volvulus. Several Th1-type (IL-2, IL-12, interferon-gamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α)) and Th2-type (IL-4, IL-5, IL-10, IL-13) cytokines were secreted by UCBC and PBMC in response to OvAg, bacterial SL-O and PHA. OvAg did not stimulate IL-2 and none of the mitogens or antigens induced production of IL-4 in neonates. In response to OvAg, substantially elevated (P < 0.01) amounts of IFN-γ were produced by UCBC from newborns of O. volvulus-infected mothers. UCBC secreted low levels of IL-5 and IL-13, while higher amounts of IL-10 were found (P < 0.01) in newborns from onchocerciasis-free mothers. In conclusion, maternal O. volvulus-infection will sensitize in utero parasite-specific cellular immune responsiveness in neonates and activate OvAg-specific production of several Th1- and Th2-type cytokines

History of orchid propagation: A mirror of the history of biotechnology

Part I Orchid seeds are nearly microscopic in size. Because of that, many fanciful theories were proposed for the origin of orchids. Almost 400 years separate the time when orchid seeds were seen for the first time and the development of a practical asymbiotic method for their germination. The seeds were first observed and drawn during the sixteenth century. Seedlings were first described and illustrated in 1804. The association between orchid and fungi was observed as early as 1824, while the requirement for mycorrhiza for seed germination was established in 1899. An asymbiotic method for orchid seed germination was developed in 1921. After Knudson's media B and C were formulated, orchids growing and hybridization became widespread. Hybrids which early growers may not have even imagined became possible. Part II A commonly held view is that Prof. Georges Morel is the sole discoverer of orchid micropropagation and that he was the first to culture an orchid shoot tip in 1960. In fact, the first in vitro orchid propagation was carried out by Dr. Gavino Rotor in 1949. Hans Thomale was the first to culture an orchid shoot tip in 1956. The methods used by Morel to culture his shoot tips were developed by others many years before he adapted them to orchids. This review also traces the history of several techniques, additives, and peculiarities (agitated liquid cultures, coconut water, banana pulp, a patent and what appears to be an empty claim) which are associated with orchid micropropagation. A summary of plant hormone history is also outlined because micropropagation could not have been developed without phytohormones. © 2009 Korean Society for Plant Biotechnology and Springer