Injection by various routes of melanoma antigen-associated macrophages: biodistribution and clinical effects

Patients' autologous macrophages (AM) were used as antigen-presenting cells (APC) in a vaccination protocol against malignant melanoma. AM were administered by various routes, including intralymphatic, since these cells did not express CCR7, a molecule required for APC migration to lymph nodes. Seven HLA-A2 patients with metastatic melanoma-two classified as M1 and five as M3-were included in the study. AM were produced from leukapheresis-separated mononuclear cells by 7-day culture with granulocyte-macrophage colony-stimulating factor. After separation by elutriation, AM were frozen in aliquots and subsequently thawed at monthly intervals, exposed to MAGE-3(271-279) peptide and injected subcutaneously into lymph nodes or into one peripheral lymph vessel. Intradermal tests were performed before and after treatment to determine peptide reactivity. No acute toxicity was observed following injection. One M1 patient had a 7-mm induration intradermal reaction response and was stabilized for 64 weeks. The M3 patients did not show any immunological or clinical response. In 11 patients, the biodistribution of 111In-labeled AM was investigated. There was no clear evidence that AM injected intradermally or subcutaneously left the site of injection. After injection into a lymph vessel of the foot region, scintigraphs showed five to ten popliteal and inguinocrural lymph nodes. This appeared to be the most efficient way to administer rapidly and safely large amounts of peptide-loaded APC into lymph nodes.     

Immune suppression and the cost of reproduction in the ground cricket, Allonemobius socius

One of the most common life history trade-offs in animals is the reduction in survivorship with increasing reproductive effort. Despite the prevalence of this pattern, its underlying physiological mechanisms are not well understood. Here we test the hypothesis that immune suppression mediates this phenotypic trade-off by manipulating reproductive effort and measuring immune function and mortality rates in the striped ground cricket, Allonemobius socius. Because A. socius males provide females with a hemolymph-based nuptial gift during copulation, and many structural components of immunity reside in the hemolymph, we also predicted that sexual selection may differentially affect how disease resistance evolves in males and females. We found that an increased mating effort resulted in a reduced immune ability, coupled with an increased rate in age-specific mortality for both sexes. Thus, immune suppression appears to be a link between reproductive effort and cost in this system. In addition, males and females appeared to differentially invest in several aspects of immunity prior to mating, with males exhibiting a higher concentration of circulating hemocytes and a superior bacterial defense capability. This pattern may be the result of previously established positive selection on gift size due to its affect on female fecundity. In short, female choice for larger gifts may lead to a sexually dimorphic immune ability.     

A direct interaction between transforming growth factor (TGF)-betas and amyloid-beta protein affects fibrillogenesis in a TGF-beta receptor-independent manner

Transforming growth factor-beta (TGF-beta) receptor-mediated signaling has been proposed to mediate both the beneficial and deleterious roles for this cytokine in amyloid-beta protein (Abeta) function. In order to assess receptor dependence of these events, we used PC12 cell cultures, which are devoid of TGF-beta receptors. Surprisingly, TGF-beta potentiated the neurotoxic effects of the 40-residue Abeta peptide, Abeta-(1-40), in this model suggesting that there may be a direct, receptor-independent interaction between TGF-beta and Abeta-(1-40). Surface plasmon resonance confirmed that TGF-beta binds with high affinity directly to Abeta-(1-40) and electron microscopy revealed that TGF-beta enhances Abeta-(1-40) oligomerization. Immunohistochemical examination of mouse brain revealed that hippocampal CA1 and dentate gyrus, two regions classically associated with Abeta-mediated pathology, lack TGF-beta Type I receptor immunoreactivity, thus indicating that TGF-beta receptor-mediated signaling would not be favored in these regions. Our observations not only provide for a unique, receptor-independent mechanism of action for TGF-beta, but also help to reconcile the literature interpreting the role of TGF-beta in Abeta function. These data support a critical etiological role for this mechanism in neuropathological amyloidoses.     

Heritability of phenolics in Quercus laevis inferred using molecular markers.

Studies of quantitative inheritance of phenotypes do not generally encompass the range of environmental conditions to which a population may be exposed in a natural setting and are rarely conducted on long-lived species due to the time required for traditional crossing experiments. We used a marker-based method to estimate relatedness with microsatellite markers in a natural population of a long-lived oak, then used this inferred relatedness to examine quantitative genetic variation in the concentration of foliar phenolics. Estimating heritability using this method requires both significant relatedness and variance in relatedness over distance. However, this population did not show significant variance of relatedness, so only the presence of heritability, and its ranking among traits and environments, could be estimated. Seven foliar phenolics showed a significant relationship between phenotypic similarity and relatedness. The significance of this relationship varied among individual phenolic compounds, as well as by season. Genetic factors appeared to have a more measurable influence on the production of secondary compounds early in the season. After leaf expansion, covariance of relatedness and phenotypic variance appear to become less significant. Therefore heritability may vary seasonally for these traits.     

GENETIC VARIATION IN CRICKET CALLING SONG ACROSS A HYBRID ZONE BETWEEN TWO SIBLING SPECIES

The sibling ground crickets Allonemobius fasciatus and A. socius meet along a mosaic hybrid zone at ≈ 40°N latitude in eastern North America. In this paper we report the findings of a genetic analysis of calling-song variation within and among six cricket populations sampled along a transect through the hybrid zone in southern New Jersey. We compared aspects of the calling song of both wild-caught and laboratory-reared crickets to test the hypothesis that population differences in song observed in the wild were genetically based. We found significant, species-level differences in all aspects of the calling song, and these differences persisted even after a generation of common-garden rearing in the laboratory, supporting the hypothesis that interspecific variation observed in the wild largely reflects genetic differentiation between the two taxa. A discriminant function analysis indicated that individual crickets could be assigned to the proper taxon with less than 10% error, supporting the premise that calling song could be used by female crickets as a mechanism for species recognition. One population, collected from within the hybrid zone and containing significant numbers of hybrid individuals, was intermediate in its calling song, presumably reflecting this population's mixed genetic makeup. In this hybrid zone population, song phenotype was highly correlated to a hybrid index score generated using species-specific alleles at four diagnostic allozyme markers, suggesting a multigenic basis to calling-song variation in these crickets as well as linkage disequilibrium between markers and song. Based on an analysis of laboratory-reared full-sib families, broad-sense heritabilities for calling-song characteristics were generally significant in the two A. socius populations, whereas many components of song showed no significant family effects in the three A. fasciatus populations. The genotypically mixed, hybrid zone population showed very high heritabilities for most calling-song components, which likely reflect the influence of interspecific gene flow on genetic variation for quantitative traits.     

Geographic variation in embryonic development time and stage of diapause in a grasshopper

Embryonic development times and the stage at which embryonic diapause occurs varied dramatically among 23 populations of the Melanoplus sanguinipes/ devastator species complex in California, USA. Grasshoppers were collected from a wide range of latitudes (32°57N to 41°20N) and altitudes (10m to 3031 m), spanning much of the variation in climatic conditions experienced by these insects in California. When reared in a common garden in the laboratory, total embryonic development times were positively correlated to the mean annual temperature of the habitat from which the grasshoppers were collected (varying from about 19 days to 32 days when reared at 27°C). These grasshoppers overwinter as diapausing eggs and the proportion of embryonic development completed prior to diapause was significantly higher in populations collected from cool habitats (>70%) than in populations collected from warm environments (<26%). The length of pre-diapause development time is determined by the stage of embryonic development at which diapause occurs, and varies considerably among populations of these grasshoppers; grasshoppers from warmer environments tend to diapause at very early stages of embryogenesis, while grasshoppers from cooler environments diapause at very late stages. The combined effect of variation in embryonic development times and variation in the stage at which diapause occurs results in a dramatic reduction in the time needed to hatch in the spring; populations from warm environments required up to 20 days (at 27°C) to hatch while populations from cool environments required as few as 5 days to complete embryonic development prior to hatching. Egg size also varied significantly among populations, but tended to be larger in populations with shorter embryonic development times. Significant family effects were observed for development time and stage of diapause, suggesting significant heritabilities for these traits, although maternal effects may also contribute to family level variation. We interpret these findings to support the hypothesis that embryonic development time and the stage of embryonic diapause have evolved as adaptations to prevailing season lengths in the study populations.     

Analysis of shoot-forming capacity in vitro in two lines of tomato (Lycopersicon esculentum Mill.) and their hybrids

Shoot differentiation in vitro of tomato plants and transmissionof this capacity into hybrids was studied. Most of the resultswere obtained with hypocotyls. The highest level of shoot formationoccurred when IAA and IPA were given, but the optimum concentrationof these growth regulators varied depending on lines and hybrids,on organs treated (hypocotyl and leaf), and on the positionof explants in these organs. Histological study of hypocotyltissues indicated that shoots were differentiated from the callusoriginating from superficial tissues. The organogenetic capacityof hypocotyls (in terms of the number of shoots per explant)of two lines and their reciprocal F₁ hybrids was modified byexogenous growth regulators. However, one parental line consistentlyshowed a higher organogenetic capacity than the other. Withregards to shoot-forming capacity, the reciprocal hybrids showed:

1. maternal effect and
2. heterosis

¹ This work was done in Laboratoire de Physiologie Pluricellulaire,C.N.R.S., Gif-sur-Yvette, France, with courtesy of Dr. H. Haradaand Dr. J. P. Pernes. (Received July 25, 1977; )     

Mechanochemical coupling in spin-labeled, active, isometric muscle

Observed effects of inorganic phosphate (P(i)) on active isometric muscle may provide the answer to one of the fundamental questions in muscle biophysics: how are the free energies of the chemical species in the myosin-catalyzed ATP hydrolysis (ATPase) reaction coupled to muscle force?. Pflugers Arch. 414:73-81) showed that active, isometric muscle force varies logarithmically with [P(i)]. Here, by simultaneously measuring electron paramagnetic resonance and the force of spin-labeled muscle fibers, we show that, in active, isometric muscle, the fraction of myosin heads in any given biochemical state is independent of both [P(i)] and force. These direct observations of mechanochemical coupling in muscle are immediately described by a muscle equation of state containing muscle force as a state variable. These results challenge the conventional assumption mechanochemical coupling is localized to individual myosin heads in muscle.     

THE EVOLUTIONARY GENETICS OF AN ADAPTIVE MATERNAL EFFECT: EGG SIZE PLASTICITY IN A SEED BEETLE

In many organisms, a female's environment provides a reliable indicator of the environmental conditions that her progeny will encounter. In such cases, maternal effects may evolve as mechanisms for transgenerational phenotypic plasticity whereby, in response to a predictive environmental cue, a mother can change the type of eggs that she makes or can program a developmental switch in her offspring, which produces offspring prepared for the environmental conditions predicted by the cue. One potentially common mechanism by which females manipulate the phenotype of their progeny is egg size plasticity, in which females vary egg size in response to environmental cues. We describe an experiment in which we quantify genetic variation in egg size and egg size plasticity in a seed beetle, Stator limbatus, and measure the genetic constraints on the evolution of egg size plasticity, quantified as the genetic correlation between the size of eggs laid across host plants. We found that genetic variation is present within populations for the size of eggs laid on seeds of two host plants (Acacia greggii and Cercidium floridum; h² ranged between 0.217 and 0.908), and that the heritability of egg size differed between populations and hosts (higher on A. greggii than on C. floridum). We also found that the evolution of egg size plasticity (the maternal effect) is in part constrained by a high genetic correlation across host plants (r_G > 0.6). However, the cross-environment genetic correlation is less than 1.0, which indicates that the size of eggs laid on these two hosts can diverge in response to natural selection and that egg size plasticity is thus capable of evolving in response to natural selection.