Relationship of B blood group locus to skin allograft in chickens

Skin grafts were exchanged among 21 genotypic pairs of B blood group locus in the non-inbred chicks of White Leghorn at 5–7 days of age. The mean percentages of B locus compatible pairs were 94.7, 84.2 and 56.8 at the 11th, 15th and 19th days after grafting, respectively. These percentages of survival grafts were significantly higher than those of incompatible pairs. The effects of three B alleles were investigated but the the differences of effects of them were not found in this experiment. Two of the prolonged survival grafts survived for 35 days after grafting and all of the incompatible grafts were rejected the 20th day after grafting. The results of skin graft provided evidence that the B blood group locus was a histocompatibility locus or closely linked to such a locus.     

Development of a semi-inbred line of Landrace pigs. I. Breeding performance and immunogenetic characteristics

During 15 years of inbreeding of pigs (Canadian Landrace) a semi-inbred line has been developed. The inbreeding coefficient (FX) is 0.84, which theoretically corresponds to between 8-9 generations of brother/sister matings. At the highest inbreeding level (0.84) the mean number of newborn piglets in the litter was 7.2 (5 litters, n = 36) including 5 stillborn (13.8%). The mean birth weight of the litter was 8.56 kg (5 litters, n = 31) the mean piglet birth weight was 1.23 kg and at the age of 21 days the mean weight of a litter was 33.24 kg with a mean piglet weight of 5.44 kg. During inbreeding, immunogenetic alloantigenic systems were investigated. Of 15 known erythrocyte systems, alleles of loci J, K, and of the most polymorphic system E, segregated. As to other immunogenetic systems (histocompatibility, leucocyte and allotypes) 2 SLA haplotypes (major histocompatibility complex) and 2 alleles of the SLC leucocyte system segregated. Allotransplants of the skin in SLA compatible siblings survived for a mean of 50.7 days (n = 77) compared with 10.8 days (n = 29) in non-inbred siblings. Tests of blastic transformation activated by T and B lymphocyte mitogens revealed a normal cell-mediated immune response. After immunization with some cell membrane alloantigens a normal humoral response was also recorded. All tested animals were halothane-resistant and tolerated a 10-min exposure to 5% without developing malignant hyperthermia. Depression due to inbreeding was manifested by a reduced reproductive ability (smaller number of piglets, frequent incidence of gonadal hypoplasia, diminution or loss of libido).     

Abo blood groups and completed reproductive performance of rural Haryanavi couples: analysing measures of selection intensities

The possible differential effects of ABO blood group materno-paternal (fetal) incompatibility on completed reproductive performance were investigated on a sample of 100 couples (100 fathers and 100 mothers) from three villages in the Jind district of Haryana state, India. The average number of live births per mating couple was slightly higher for the incompatible matings (5.32) than the compatible ones (5.05). This advantage was offset by higher postnatal mortality in the former. Consequently, the average number of living children in the compatible matings (4.64) was higher than in the incompatible ones (4.18). With reference to individual ABO matings, the index of relative fertility (Irf) was the highest in A x AB followed by B x A type of incompatible matings. No decrease in live births in O x A and O x B incompatible matings was observed compared with their reciprocal compatible ones, i.e. A x O and B x O matings, as has been hypothesized in previous studies. The total pregnancy wastage was substantially higher in ABO-incompatible matings (24.59%) than compatible matings (8.45%). About 71% of the postnatal deaths took place within one year of the birth in the case of incompatible matings compared with 50% in the case of compatible matings. The study supports the hypothesis that selection is operative at the ABO locus as revealed by the measures of selection intensity. The loss of fitness in the present sample was associated with differential mortality. There were no differences in the proportions of average number of male live births in the compatible (0.55) and incompatible matings (0.58). However, in the individual mating types, there was some evidence of higher or lower proportions of male live births.     

Seed production from the mixed mating system of Chesapeake Bay (USA) eelgrass (Zostera marina; Zosteraceae)

In monoecious plants, gametes can be exchanged in three ways: among unrelated genets (outbreeding), with close relatives (inbreeding), or within individuals (geitonogamous selfing). These different mating systems may have consequences for population demography and fitness. The experiment presented herein used artificial crosses to examine the mating system of Chesapeake Bay, Virginia, USA eelgrass (Zostera marina L; Zosteraceae), a bisexual submerged aquatic plant that can outbreed, inbreed, and self. Genetic data indicate severe heterozygosity deficiencies and patchy genotype distribution in these beds, suggesting that plants therein reproduce primarily by vegetative propagation, autogamy, or geitonogamy. To clarify eelgrass reproductive strategies, flowers from three genetically and geographically distinct beds were hand-pollinated in outbred, inbred, and selfed matings. Fertilization success and seed production, life history stages which contribute greatly to the numeric maintenance of populations, were monitored. We found no evidence that inbreeding had negative consequences for seed production. On the contrary, selfed matings produced seeds significantly more frequently than outcrossed matings and produced significantly larger numbers of seeds than either inbred or outbred matings. These results contrast with patterns for eelgrass in other regions but might be expected for similar populations in which pollen limitation or a short reproductive season renders selfing advantageous.     

Survival of heterotopic heart xenografts from Helisoma duryi,Planorbula armigera,and Planorbarius corneus in Biomphalaria glabrata (Pulmonata,Basommatophora, Planorbidae): evidence for phylogenetic relatedness?

Abstract. Heart xenografts from the pulmonate snail Helisoma trivolvis survive in Biomphalaria glabrata , whereas xenografts from most other pulmonate snail genera are rejected within 3 to 15 days. To test whether xenografts from snails closely related to H. trivolvis were also accepted, specimens of an albino strain of B. glabrata were implanted with hearts from H. duryi, Planorbula armigera , and Planorbarius corneus . The fate of implants was monitored for 180 days by measuring heartbeat and by histological analysis. All 3 types of implants survived beyond the 3 to 15 days required for the complete destruction of incompatible xenografts, suggesting a degree of physiological and immunological compatibility between B. glabrata and these donors. Among the 3 types of xenografts, all from H. duryi survived for the entire 180 days. Fewer grafts from P. armigera and P. corneus survived for prolonged periods, although some still were beating at 60 and 180 days post implantation (DPI) respectively, suggesting that a range of histocompatibility, and perhaps phylogenetic relatedness, with B. glabrata occurs within this group. Paradoxically, the initial hemocytic response by the recipient was strongest against grafts from H. duryi , the most compatible donor, while responses to grafts from P. armigera and P. corneus were mild or did not occur during the first 7 DPI. We used 2 albino strains of B. glabrata in these studies, and the data suggest slight differences in recipient strain compatibility.     

ABO blood groups and fertility in an Indian population

A total of 589 compatible mating couples could be investigated against 432 incompatible mating couples in order to determine the selective mechanism operating on ABO blood groups. There appears to be no striking difference in the proportion of childless couples between the two groups. The mean number of living children presents a significant difference. There is 21% deficiency of 'A' children in the two groups. Similarly, there is 16% deficiency of 'B' children in the two groups. It appears that there is 31.9% fetal wastage in incompatible matings as compared with 17.15% in compatible matings.     

Inbreeding in a natural population of Euodynerus foraminatus (Hymenoptera: Vespidae), a solitary wasp with single-locus complementary sex determination

The solitary wasp Euodynerus foraminatus has single-locus complementary sex determination (sl-CSD), which is normally incompatible with inbreeding because it increases the production of sterile or inviable diploid males. Previous field observations of E. foraminatus have suggested that high levels of sibling mating are present in this species. However, conclusions about inbreeding and its genetic consequences could be flawed if based solely upon behavioural observations. Through microsatellite DNA genotyping of 102 E. foraminatus females in southwest Michigan, we estimate that between 55% and 77% of the matings in this population take place between siblings, but the frequency of diploid males is lower than expected. Our data suggest that a mixture of inbreeding and outbreeding persists in E. foraminatus despite the presence of sl-CSD.     

Histocompatibility analyses in tetraploids induced from clonal triploid crucian carp and in gynogenetic diploid goldfish

Histocompatibility analyses in goldfish were performed using the tetraploid goldfish-crucian carp hybrid and the first generation of gynogenetic diploid (GD₁) goldfish. Tetraploids were obtained by crossing clonal triploid crucian carp with goldfish. GD₁ goldfish were produced by the suppression of the second meiotic division. Tetraploid scale grafts on triploid clone members evoked an acute rejection in 4–6 days, whereas the reverse transplants were accepted or rejected chronically. Reciprocal grafting between tetraploids showed subacute rejection in 10–12 days, although some fish showed chronic rejection in 20–30 days. On the other hand, scale grafts reciprocally exchanged among triploids were intact even 3 months after grafting, although some of them showed a unidirectional rejection pattern. Furthermore, allograft rejection among gynogens occurred between 5 and 20 days, whereas all the scale allografts between members of control siblings were rejected within 9 days. In addition, neither accelerated acute rejection nor acceptance of allografts was observed in grafts exchanged among GD₁ goldfish. These results suggest that single doses of histocompatibility alleles are effective in eliciting acute rejection, and each of the fourth haploid set of chromosomes originating from paternal goldfish might share the same histocompatibility antigens to a large extent. This experiment also indicates that the genecentromere recombination rate is quite high with respect to the histocompatibility loci in this species.     

Frequencies of Mitochondrial DNA Haplotypes in Laboratory Cage Populations of the Mosquito, Aedes Albopictus

A laboratory cage experiment was undertaken to study changes over time in the frequencies of two mitochondrial DNA (mtDNA) haplotypes in the mosquito, Aedes albopictus, under two conditions: bidirectionally compatible matings and unidirectionally incompatible matings. Frequencies were monitored for 10 generations in three replicate cages for each of the two conditions above. In cages with bidirectionally compatible strains, changes in haplotype frequencies were nondirectional and neither haplotype increased in frequency. Statistical analysis of relative proportions of the two haplotypes in each generation indicated that the magnitude of the observed fluctuations could be expected under an assumption of random genetic drift alone. In cages with unidirectionally incompatible matings, mtDNA of females that lay inviable eggs upon mating with males of another strain, decreased significantly in the F1 generation and was completely replaced in the F2 generation.     

ABO blood groups and fertility—with special reference to intrauterine selection due to materno-fetal incompatibility

The purpose of the present investigation was to study whether there is differential fertility between different mating types of ABO blood group system. Selective force which is operating through maternal-fetal incompatibility has been observed in the differential fertility between compatible and incompatible mating groups in the present sample of 183 families of Visakhapatnam town of Andhra Pradesh, India. The differences in the mean numbers of pregnancies as well as living children between the two major mating groups, compatible and incompatible are significant. The fertility rates of O fathers and O mothers were significantly higher than those in matings in which neither parents belongs to O. The selection is operating to reduce the gene ratio of A and to increase the gene ratios of O and B in this sample.     

Prolongation of skin allograft survival after neonatal injection of donor bone marrow and epidermal cells

Composite-tissue (e.g., hand allograft) allotransplantation is currently limited by the need for immunosuppression to prevent graft rejection. Inducing a state of tolerance in the recipient could potentially eliminate the need for immunosuppression but requires reprogramming of the immunological repertoire of the recipient. Skin is the most antigenic tissue in the body and is consistently refractory to tolerance induction regimens using bone marrow transplantation alone. It was hypothesized that tolerance to skin allografts could be induced in rats by injecting epidermal cells with bone marrow cells during the first 24 hours of life of the recipients. Brown Norway rats (RT1n) served as donors for the epidermal cells, bone marrow cells, and skin grafts. Epidermal cells were injected intraperitoneally and bone marrow cells were injected intravenously into Lewis (RT1l) newborn recipient rats. In control groups, recipients received saline solution with no cells (group I, n = 12), bone marrow cells only (group II, n = 15), or epidermal cells only (group III, n = 15). In the experimental group (group IV, n = 18), recipients received epidermal and bone marrow cells simultaneously. Skin grafts were transplanted from Brown Norway (RT1n) rats to the Lewis (RT1l) rats 8 weeks after cell injections. Skin grafts survived an average of 8.5 days in group I (10 grafts), 9.2 days in group II (12 grafts), and 12 days in group III (14 grafts). Grafts survived 15.5 days (8 to 26 days) in group IV (15 grafts). The difference was statistically significant (p < 0.05). Hair growth was observed in some accepted grafts in group IV but never in the control groups. This is the first report of prolonged survival of skin allografts in a rat model after epidermal and bone marrow cell injections. Survival prolongation was achieved across a major immunological barrier, without irradiation, myeloablation, or immunosuppression. It is concluded that the presentation of skin-specific antigens generated a temporary state of tolerance to the skin in the recipients that could have delayed the rejection of skin allografts.     

木耳和毛木耳的极性研究*

从木耳(Auricularia auricula)和毛木耳(A.polytricha)的同一子实体弹射、分离30个单孢子并发育成单核菌丝体,各自分成3组,以10×10方式进行单核体两两配对。取两配对单核体交结处菌丝体块到新的平板上继续发育并插入无菌的盖玻片让其菌丝爬上。后利用双苯并咪唑(Hoechst 33258)染色,在萤光显微镜下逐块检查配对后菌丝体细胞中核的数目。如果出现双核,再加以检查锁状联合以验证,则为配对亲和。不亲和者仍为单核。根据配对行为进行不亲和因子分配决定其交配型。检测结果表明,木耳和毛木耳担孢子的性别是由一对遗传因子A.a所控制。属典型性二极性(bipolar)异宗结合。     

木耳和毛木耳的极性研究

从木耳(Auricularia auricula)和毛木耳(A.polytricha)的同一子实体弹射、分离30个单孢子并发育成单核菌丝体,各自分成3组,以10×10方式进行单核体两两配对。取两配对单核体交结处菌丝体块到新的平板上继续发育并插入无菌的盖玻片让其菌丝爬上。后利用双苯并咪唑(Hoechst 33258)染色,在萤光显微镜下逐块检查配对后菌丝体细胞中核的数目。如果出现双核,再加以检查锁状联合以验证,则为配对亲和。不亲和者仍为单核。根据配对行为进行不亲和因子分配决定其交配型。检测结果表明,木耳和毛木耳担孢子的性别是由一对遗传因子A.a所控制。属典型性二极性(bipolar)异宗结合。     

Analysis of Inbreeding Depression in Agaricus Bisporus

Inbreeding depression was observed in the commercial button mushroom, Agaricus bisporus, by examining two laboratory populations. The outbred population consisted of 20 compatible pairings, 10 homokaryons with each of the homokaryons Ag1-1 and Ag89-65. The inbred population consisted of 104 backcrosses (among which 52 were expected to be sexually compatible) obtained from the pairings of two progenitor homokaryons, Ag1-1 and Ag89-65, with 52 progeny homokaryons derived from the mating between Ag1-1 and Ag89-65. The eight fitness components examined for these two populations were successful matings as identified by the analysis of restriction fragment length polymorphisms, positive mycelial interaction in these successful matings, heterokaryon growth rate, primordium formation by the successful matings, fertile fruiting body formation, time to first break, average number of fruiting bodies per square foot, and average weight per fruiting body. The outcrossed population showed a significant advantage over the inbred population in three of eight fitness components. Two pairs of traits were significantly correlated. The multiplicative fitness ratio of the inbred to the outcrossed population was 0.18. The relevance of inbreeding depression to the evolution of fungal mating systems and to mushroom breeding is discussed.     

Value of Prospective Tissue Typing in Kidney Transplantation Between HL-A Identical Siblings

The predictability of leucocyte typing in kidney transplantation was assessed by an analysis of 37 kidney transplants from sibling donors. Recipients who were identical for the HL-A antigens with their donors gave highly predictable results. In comparison with those siblings who were incompatible or compatible but not identical their grafts functioned earlier, they required less immunosuppression, and had never had any rejections. They also appeared to have less postoperative morbidity. These results indicate that less immunosuppression than is current in many transplant centres could well be used with benefit in HL-A identical sibling transplants. This could reduce the risk of infection and possibly minimize the adverse effects of steroids on wound healing in these patients.     

Variation in inbreeding depression among populations of the seed beetle, Stator limbatus

Inbreeding depression has been documented in many insect species, but the degree to which it varies among traits within populations and among populations within species is poorly understood. We used a single‐generation factorial breeding design to examine variation in inbreeding depression among three populations of the seed‐feeding beetle, Stator limbatus Horn (Coleoptera: Chrysomelidae: Bruchinae), from the southwestern USA. Eggs from sib matings were less likely to develop and hatch, and larval hatch‐to‐adult mortality was higher for offspring of sib matings. Overall, inbreeding resulted in a reduction in the proportion of eggs that produced an adult from >80% for outbred matings in all three populations to an average of only 54% for inbred matings. Of those larvae that survived to adult, inbred beetles took ～1.5 days (>5%) longer to reach adult. The only measured trait not affected by inbreeding was adult body mass. The degree to which inbreeding increased mortality varied among the populations – inbreeding depression was lowest in the population that is most isolated. Although populations of S. limbatus are generally large in nature our results suggest that increased inbreeding associated with population fragmentation can have substantial effects on fitness of S. limbatus.     

The transition to social inbred mating systems in spiders: role of inbreeding tolerance in a subsocial predecessor

The social spiders are unusual among cooperatively breeding animals in being highly inbred. In contrast, most other social organisms are outbred owing to inbreeding avoidance mechanisms. The social spiders appear to originate from solitary subsocial ancestors, implying a transition from outbreeding to inbreeding mating systems. Such a transition may be constrained by inbreeding avoidance tactics or fitness loss due to inbreeding depression. We examined whether the mating system of a subsocial spider, in a genus with three social congeners, is likely to facilitate or hinder the transition to inbreeding social systems. Populations of subsocial Stegodyphus lineatus are substructured and spiders occur in patches, which may consist of kin groups. We investigated whether male mating dispersal prevents matings within kin groups in natural populations. Approximately half of the marked males that were recovered made short moves (< 5m) and mated within their natal patch. This potential for inbreeding was counterbalanced by a relatively high proportion of immigrant males. In mating experiments, we tested whether inbreeding actually results in lower offspring fitness. Two levels of inbreeding were tested: full sibling versus non-sib matings and matings of individuals within and between naturally occurring patches of spiders. Neither full siblings nor patch mates were discriminated against as mates. Sibling matings had no effect on direct fitness traits such as fecundity, hatching success, time to hatching and survival of the offspring, but negatively affected offspring growth rates and adult body size of both males and females. Neither direct nor indirect fitness measures differed significantly between within patch and between-patch pairs. We tested the relatedness between patch mates and nonpatch mates using DNA fingerprinting (TE-AFLP). Kinship explained 30% of the genetic variation among patches, confirming that patches are often composed of kin. Overall, we found limited male dispersal, lack of kin discrimination, and tolerance to low levels of inbreeding. These results suggest a history of inbreeding which may reduce the frequency of deleterious recessive alleles in the population and promote the evolution of inbreeding tolerance. It is likely that the lack of inbreeding avoidance in subsocial predecessors has facilitated the transition to regular inbreeding social systems.     

Structures of Conversion Products Formed from 18β-Glycyrrhetinic Acid by Streptomyces sp. G-20

Dynamic profiles of the rate of O₂ generation from press-injured and inoculated rice leaf slices, versus the time after inoculation, discriminated between the incompatible and compatible combination of blast fungus races with a cultivar. The application of sodium saccharin to rice seedlings via the root system for 6 days changed the compatible to incompatible profile. Even after press- injury and inoculation with the compatible conidia, the leaf application of sodium saccharin enhanced superoxide generation. The application of N-methylsaccharin in a similar manner, however, did not enhance the superoxide generation. Inoculation of press-injured leaves with incompatible conidia in the presence of an aqueous diffusate of the germinating compatible conidia changed the incompatible to compatible profile. The application to press-injured of concanavalin A or a lyophylized preparation from 5 m ammonia extracts of rice leaf homogenate prior to stimulating with a resistance-inducing factor (RIF) from the fungus also enhanced the superoxide generation. The RIF, either from the incompatible or compatible race, gave a quite similar profile of activation upon the generation of the superoxide anion.     

Skin graft survival in genetically identical cloned pigs

Nuclear transfer technology allows for the reprogramming of somatic cells, and the production of embryonic stem cells and animals that are genetically identical in terms of nuclear DNA to the parental somatic cell. It is assumed that these products of nuclear transfer technology will be immunologically compatible to each other in spite of the fact that there are data that show differences in the expression patterns and phenotypes between animals produced by nuclear transfer. We have produced a series of cloned pigs from embryonic fibroblasts. Microsatellite analysis was used to confirm that the clones were genetically identical. Skin transplants were performed to assess immunological reactivity. Skin transplants between genetically identical cloned pigs were accepted, whereas third party grafts were rejected. Histological analysis of the grafts showed edema and mononuclear cell infiltrates in the recipient's skin in rejected grafts and not in grafts that were accepted. Our data supports the notion that genetically identical cloned pigs are immunologically compatible.     

Growth and carbon partitioning in compatible and incompatible peach/plum grafts

The shoot growth of compatible ( Prunus persica L. Batsch cv. Springtime grafted on Prunus cerasifera L. Ehrh cv. Myrobolan P2032) and incompatible ( Prunus persica L. Batsch cv. Springtime grafted on Prunus cerasifera L. Ehrh cv. Myrobolan P18) peach/plum grafts was observed over a period of 100 days after grafting under controlled conditions. Leaf and root activities were determined by studying carbon assimilation and partitioning, leaf mineral contents and water relations. Shoot length and leaf number were not significantly affected in the incompatible combination during the first 55 days after grafting, but then, shoot growth rate was significantly reduced. Final total dry weights of the shoot were similar in both graft combinations. The incompatible combination did not show any water stress. Soluble sugar and starch contents increased in the leaves of the incompatible combination, accounting for about 36% of the increase of leaf dry weight per unit area. Photosynthesis was affected by the compatibility of the grafts. Leaf nitrogen content (% dry weight) fell in the incompatible graft combination 65 days after grafting. However, nitrogen content on an area basis was not affected. The possibility of nitrogen stress is discussed.