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PubMed1976

Kinetics of horseradish peroxidase migration through cerebral cortex.

This study provides a semiquantitative description of the migration of the extracellular space marker, horseradish peroxidase (HRP), through the cerebral cortex. Following a continuous subarachnoid infusion of HRP, this marker was fixed rapidly within the cortical extracellular space (ECS) by intravascular aldehyde perfusion fixation. Microscopic measurements of the maximum depth of penetration of HRP into the cortex perpendicular to the pial surface were taken from coronal whole brain sections of rabbits that had been exposed to HRP for varying periods of time. The depth of penetration plotted as a function of time of exposure to HRP produced a 'diffusion profile'. The failure of experimental points to conform to an ideal diffusion curve indicates that simple diffusion alone is an inadequate explanation of the rate of movement of large molecular solutes from the subarachnoid space through the cerebral cortical ECS. The complex pattern of migration velocity of HRP through cortex may be due to alterations of flux of this solute which result from variations in the volume of ECS in different cortical laminae and to the presence of bulk flow of extracellular fluid in the deeper cortical regions.

Animals↗
PubMed2001

Immigration and the regional demographics of the elderly population in the United States.

OBJECTIVES: This research examined the impacts of past international and interregional migration flows on regional elderly population growth and distribution patterns. METHODS: The authors used 1960, 1970, 1980, and 1990 Census data and multiregional demographic models to analyze changes in the sources of regional elderly population growth rates, age compositions, and spatial distributions over time. RESULTS: Past elderly interregional migration patterns have exhibited considerable stability and have contributed less than aging-in-place in shaping regional elderly population geographies. Also the effects of immigration on elderly dependency ratios have been very modest. DISCUSSION: Little evidence exists of any significant breaks with past trends in internal elderly migration patterns. Reconstruction of elderly population changes between 1950 and 1990 reveals that the driving force behind the changes was net aging-in-place and not net migration. Finally, analysis of the possible population rejuvenating effects of immigration suggests that although its impact has contributed to lower elderly-to-worker dependency ratios, its level over the past decades has been insufficient to counteract the much stronger countervailing impact of population aging.

Aged↗
PubMed1994

[Migration, marriage, and family in the valley of the Senegal River].

"In 1993, out migration from five villages in the upper valley of the Senegal river appears to be as intensive as it was ten years ago, but with the difference that new social groups are now concerned: children, women, and older men. Migration of family groups is essentially characteristic of international migrants, although all the members of the family do not always move to the same place. Besides pendular and incomplete migrations, settlement in Dakar can be observed, probably corresponding to a progressive [severance] from the village of origin. Exogamy and nonresidential polygamy also contribute to a multilocalization of the family and of the community of origin, thus strengthening the flows of migrants, especially to Dakar." (SUMMARY IN ENG AND SPA)

Africa↗
PubMedDate not supplied

Alterations of mouse embryonic branchial nerves and ganglia induced by ethanol.

An immunostaining technique using monoclonal antibodies to a neurofilament protein has allowed us to visualize defects in the development of cranial nerves and ganglia of 10 to 10.5 days mouse embryos following exposure to ethanol in whole embryo culture. Reference patterns for development of cranial nerves and ganglia of control mouse embryos explanted and examined when they had 25 to 34 pairs of somites were established. Additionally, control mouse embryos were grown in whole embryo culture for 48 h, with culture being initiated in embryos having 6 to 7 somite pairs. At the end of the culture period, only minor differences were observed between the control groups. An experimental group of embryos was cultured in the presence of increasing doses (1.6, 3.2, 4, and 4.8 g/l) of ethanol. Defects were observed in the development of the glossopharyngeal and vagus nerves. These abnormalities included absence of the dorsal root (superior ganglion) of IX, star-like shape of inferior ganglion IX, disorganization of the rootlets of nerve X and abnormal fibers between the two nerves and ganglia. These results suggest that the migration and patterning of neural crest cells derived from r6 and r7 may be particularly affected by ethanol. The results also demonstrate the usefulness of this approach in evaluating the susceptibility of the developing cranial nerves to toxicant exposure.

Animals↗
PubMed2004

Prespecification and plasticity: shifting mechanisms of cell migration.

Cell migration is a universal process involving different morphologies and mechanisms in different cell types and tissue environments. Prespecified cell-type-specific patterns of cell migration can be classified into single cell migration (amoeboid, mesenchymal) and collective migration modes (cell sheets, strands, tubes, clusters). These intrinsic molecular programs are associated with a characteristic structure of the actin cytoskeleton, as well as the cell-type-specific use of integrins, matrix-degrading enzymes (matrix metalloproteinases and serine proteases), cell-cell adhesion molecules (cadherins and activated leukocyte adhesion molecule), and signaling towards the cytoskeleton (carried out by RHO GTPases). In response to the gain or loss of these key molecular determinants, significant adaptation reactions can modify the cell's shape, pattern, and migration mechanism; examples of this include the epithelial-mesenchymal transition, mesenchymal-amoeboid transition and collective-amoeboid transition.

Animals↗
PubMed1997

Detection and characterization of an activity which aligns mesodermal cells into parallel arrays.

A cell line of mesodermal origin, FS9, was found to release a Cell Orienting Factor into its culture medium. In contrast with the random migration of controls, the orienting activity causes migrating mesenchymal cells to form an orderly "halo' surrounding tissue explants; individual cells and their cytoskeletons are elongated and parallel to each other but at right angle to the explant. No effect on the rate of cell movement was apparent. The orienting activity could be quantified by counting the number of cells found within strings radiating at right angles to a single tissue explant in the presence of FS9 conditioned medium or by using NIH image analysis. A dose dependent relationship with half maximal activity occurring at a 25% dilution of conditioned medium was observed. Cells that migrated randomly in the absence of conditioned medium became oriented within 4 h of exposure to 50% conditioned medium. Conversely, when the conditioned medium was removed, parallel alignment was rapidly lost. The orienting activity was found in conditioned media from a variety of mesodermal derivatives. Transformation of Balb/c 3T3 cells using EJ-ras oncogene led to augmented production of the activity. Furthermore, insulin was required in serum-free medium to support its production, Laminin, fibronectin and collagen and a range of pure cytokines, neither promoted nor inhibited orientation. Cell alignment was also unaffected by treatments which interfered with cell-substrate interactions and motility including the addition of the RGD peptide or anti-integrin beta 1 and beta 3 antibodies. A protein is likely to be involved since the activity was heat and trypsin sensitive and non-dialysable. The possibility is discussed that the orienting activity is a novel protein(s) which alters intercellular interactions to promote the formation of an aligned pattern by migrating mesenchymal cells.

3T3 Cells↗
PubMed1986

Migration of the schistosomula of Schistosoma mansoni in mice vaccinated with radiation-attenuated cercariae, and normal mice: an attempt to identify the timing and site of parasite death.

The migration of the schistosomula of Schistosoma mansoni labelled with [75Se]methionine, has been followed from the skin to the hepatic portal system. Parasites were detected in all mouse tissues by compressed organ autoradiography. Two separate experiments were performed to track parasites in normal mice, and in mice previously vaccinated with irradiated cercariae. In normal mice, the profile of numbers of autoradiographic foci detected in the skin, lungs, systemic and splanchnic organs was described with time post-infection. The distribution of parasites to systemic organs, following exit from the lungs, paralleled the fractional distribution of cardiac output. Accumulation of schistosomula in the hepatic portal system was complete by day 21 post-infection. Only 2-3 passes of parasites around the vascular system would be required to produce the hepatic portal population. No significant decline in total foci was detected in the first 12 days post-infection. The majority of parasite elimination appeared to occur in the lungs as late as day 21, with lesser proportions in the systemic organs and skin infection site. The pattern of migration in vaccinated mice was similar to that in normal animals. One difference observed was the longer duration of stay in the skin; however, the majority of parasites eventually reached the lungs. The systemic phase of migration occurred on a reduced scale, as did accumulation of parasites in the hepatic portal system. The decline in total foci in vaccinated mice commenced approximately 7 days earlier than in normal mice and proceeded to a lower end-point. Again the majority of parasite elimination appeared to occur in the lungs with lesser proportions in the systemic organs and skin infection site. It is suggested that resistance to reinfection in vaccinated mice has two additive components which combine to retard the migration of schistosomula within the vasculature, preventing them from reaching the hepatic protal system.

Animals↗
PubMed1992

Long-term survival of mouse corpus callosum grafts in neonatal rat recipients, and the effect of host sensitization.

Previous studies have suggested that the incidence of spontaneous rejection among immunogenetically mismatched neural transplants in neonatal recipients varies significantly depending on the cellular composition of the graft material. For example, neuron-rich grafts of embryonic mouse retina generally survive for extended periods without showing signs of rejection after implantation into neonatal rats, whereas cortical xenografts, which contain abundant glial and endothelial cells as well as neurons, typically undergo rejection 4-6 weeks after implantation. To determine whether the presence of donor glia is responsible for this high incidence of spontaneous rejection, we examined the fate of a non-neuronal graft material composed predominantly of xenogeneic glial cells (post-natal day 3, PD3, CD-1 mouse corpus callosum) implanted into the mesencephalon of PD1 Sprague-Dawley rats. The distribution and survival of donor astrocytes were assessed using a monoclonal antibody specific for a mouse astrocyte surface antigen, M2. Thirteen of 16 animals sacrificed within 2 months of implantation had detectable transplants. In these animals, M2-positive cells frequently migrated well away from body of the graft, clustering in large numbers in several characteristic regions of the host brain. Unlike cortical grafts of similar age, the vast majority (93%) of callosal transplants showed no histological signs of rejection or major histocompatibility complex antigen expression in and around the transplant-derived cells. As previously noted in the neonatal retinal transplant paradigm, however, well-integrated 1-month-old corpus callosum grafts could be induced to reject by appropriate sensitization of the host immune system, implying that the host was not immunologically tolerant to the foreign neural graft. With longer survival times in unsensitized hosts, a progressively smaller percentage of animals had detectable donor astrocytes (5 of 10 animals at 3 months postimplantation and 4 of 16 animals at 4 months); in those 9 animals with surviving grafts, only small numbers of M2-positive cells were seen within the graft bed and surrounding host brain. However, only 2 of the 26 "long-term" animals showed evidence of graft rejection. These results indicate that mouse astrocytes show characteristic patterns of migration into the host brain when implanted into neonatal rats; however, these xenogeneic cells have a limited duration of survival. The infrequency with which even subtle signs of spontaneous rejection were detected in animals that had received corpus callosum xenografts suggests that an immune-mediated process is unlikely to be responsible for the time-dependent elimination of the donor astrocytes.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1983

Marriage migration, a neglected form of long-term mobility: a case study from Ilorin, Nigeria.

"This article examines the evidence for and possible significance of marriage migration in and around the city of Ilorin, the capital of Kwara State, Nigeria, which has a population of about 400,000." The study "reveals a movement of rural women to marry into wealthy polygymous compounds in the city and the return of some of these women to their rural natal compounds later in life. This movement may be an explanation for the high proportion of women in indigenous towns, and perhaps also in some newer medium-sized settlements. It can also be seen as a reflection of the unequal and exploitive relationship between the towns and their rural hinterland."

Africa↗
PubMed1980

Locomotion and cell-substratum contacts of Xenopus epidermal cells in vitro and in situ.

Studies of tissue cell locomotion in culture have revealed much about cell motility, but whether behaviour in vitro resembles movement of the same cells in the animal is not clear. To investigate this, I compared the locomotion and cell-substratum contacts of epidermal cells from Xenopus tadpoles, migrating from explants on glass and plastic, with the same cells spreading in vivo during wound closure. Time-lapse cinemicrography showed that in both cases, cells spread by extending broad lamellipodia across the substratum, and did not form microspikes, filopodia, or blebs. The net rate of translocation was significantly slower in vitro, however, because cells both protruded lamellipodia slower and spent more time stationary or withdrawing, compared with cells in situ. The increased fluctuation seemed in part due to greater tension within the expanding sheet in vitro, since when tension was reduced, for example by wounding, the cells spread with less fluctuation and at a greater rate (6.5 micrometers/min compared with 0.77 micrometers/min). Micromanipulation showed that cells adhered to the substratum, both in situ and in vitro, by a broad contact where transmission electron microscopy (TEM) of sectioned material showed the cells to be less than 30 nm from the substratum. A similar separation was observed beneath cells in vitro when viewed in life with interference-reflexion optics (IRM). A few focal contacts (adhesion plaques) were also seen with IRM and TEM of cells in vitro, but were not seen with TEM of cells in situ. Submarginal as well as marginal basal cells of the advancing sheet adhere and spread on the substratum in both situations, whereas cells of the outer layer are passive. Hence, the overall pattern of migration of these cells is similar in vitro and in situ; the differences in rates of movement may be explained in part by the different degree of tension in the epithelium under the 2 conditions.

Animals↗
PubMed1993

Development of geniculocortical projections to visual cortex in rat: evidence early ingrowth and synaptogenesis.

Anterograde movement of DiI and transneuronal transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) were used to study the temporal and laminar patterns of ingrowth of the geniculocortical projection to visual cortex in fetal and postnatal rats. The development of this projection was compared to patterns of migration and settling of [3H]-thymidine-labeled neurons destined for cortical layer IV, and to geniculocortical synapse formation. DiI-labeled geniculocortical axons were found in the intermediate zone beneath the lateral cerebral mantle at embryonic day (E)17 and in the subplate layer underlying visual cortex by E18. On E19 they appeared to accumulate and grow radially into an expanding subplate layer and into the deep part of developing cortical layer VI. By postnatal day (P)0, DiI or WGA-HRP-labeled geniculocortical axons were found in developing cortical layers VI and V. By P1, they invaded the deep portion of the cell-dense cortical plate, where they were in position to make initial contact with neurons that would later form layer IV. A few axons traversed the cortical plate to reach the marginal zone. Layer IV became an identifiable layer on P2, and a clear projection to layer IV was evident by P3. These results suggest that geniculocortical afferents grow continuously from the intermediate zone, initially into an expanding subplate layer and then sequentially into each of the developing cortical layers without evidence of "waiting." Electron microscopic data suggest that geniculocortical axons begin to form immature synapses with dendrites and neuronal perikarya as they first encounter cortical neurons, first in the subplate layer and then in developing layers VI, V and marginal zone, in addition to the primary target layer IV. The precise targeting and overall temporal and laminar patterns of ingrowth and synaptogenesis suggest that geniculocortical axons are directed to the visual cortex by guidance cues within the internal capsule and subplate. Further, they reach the occipital pole early enough to influence the specification and histogenesis of cortical area 17, perhaps by exerting an influence on the deep-to-superficial "wave" of neuronal differentiation in sequentially developing subplate and cortical layers VI, V and IV.

Afferent Pathways↗
PubMed1992

Relationship between mast cell degranulation and jejunal myoelectric alterations in intestinal anaphylaxis in rats.

The effects of two degranulators of mast cells and intestinal anaphylaxis on jejunal myoelectric activity were compared in rats fasted for 15 hours. Attempts to antagonize the motility changes were performed using antagonists of histamine and serotonin and a cyclooxygenase and lipoxygenase inhibitor. Hooded Lister rats were chronically fitted with electrodes implanted in the jejunal wall. A group of rats was sensitized to egg albumin and challenged 14 days later by intraduodenal infusion of antigen. Sensitized animals had serum titers greater than or equal to 1:64. The other group was administered with mast cells degranulators. Both 48/80 (1 mg/kg), a degranulator of connective mast cells, and bromolasalocid (2 mg/kg), acting on connective and mucosal mast cells, induced a phase of total spiking inhibition followed by a progressive irregular spiking activity until the recovery of migrating myoelectric complex pattern (about 3 hours after injection). In contrast, antigen challenge disrupted the migrating myoelectric complex pattern, which was replaced by a peculiar pattern characterized by propagated spike burst, lasting 98 +/- 11.3 minutes. Chlorpheniramine (1 mg/kg) antagonized only the inhibitory phase induced by degranulators and was ineffective on the intestinal anaphylaxis-induced motor changes. Methysergide (1 mg/kg) and indomethacin (5 mg/kg) significantly reduced the degranulator effects as well as the anaphylaxis-induced alterations of intestinal motility. It is concluded that anaphylaxis-induced motor disturbances are relevant to mucosal mast cell degranulation involving 5-hydroxytryptamine and arachidonic acid derivative products, whereas histamine release appears to be a minor component.

Anaphylaxis↗
PubMedDate not supplied

Structure and function in the ruminant synepitheliochorial placenta: central role of the trophoblast binucleate cell in deer.

The ruminant placenta has a very uniform gross structure based on localised areas of fetomaternal membrane apposition and proliferation to form placentomes. There is no consistency, however, in the number or size of these placentomes (6-150), nor in the villus architecture of the individual placentome. The one consistent feature is the binucleate cell (BNC) population in the trophoblast. These BNC form 15-20% of the epithelium in all ruminants examined so far. They synthesise the placental lactogen hormone and other glycoproteins and migrate through tight junctions to fuse with a uterine epithelial cell to form initially fetomaternal hybrid trinucleate cells (TNC) and subsequently syncytial plaques (SP). Such SP may be transient or persist throughout pregnancy depending on the species. The wide range of deer species examined confirms the uniformity of the BNC hormone production, migration, and fusion pattern described for other ruminants. BNC migration produces predominantly transient TNC, but there are areas of SP largely restricted to the apex of the maternal crypts. Maternal large granule lymphocytes (LGL) are uniquely found in deer placentomal uterine epithelium; they are usually closely associated with TNC and SP sites, but the significance of the interactions remains to be established.

Animals↗
PubMed1989

Inherited diseases in North American Mennonites: focus on Old Colony (Chortitza) Mennonites.

The patterns of migration and the genetic disorders occurring among North American Mennonites are reviewed, and inherited conditions recently recognized in a religious and genetic isolate, the Old Colony (Chortitza) Mennonites, are described. Old Colony Mennonites are of Dutch/German origin and descend from approximately 400 founding families who settled in the Old Colony, Chortitza (the Ukraine, USSR) in the late 1700s, and then migrated to Canada and Central and South America in the past century. We investigated over 6 generations of a Canadian Old Colony kindred in which there was extensive intermarriage, and in whom 28 individuals developed diabetes mellitus. Insulin-dependent diabetes mellitus (IDDM) occurred in 14 affected individuals in 10 closely related sibships; the 11 living IDDM patients were all concordant for the immunogenetic marker HLA-DR4. Fourteen close relatives had other disorders of carbohydrate metabolism, including gestational diabetes and non-insulin-dependent diabetes mellitus. Other close relatives had autoimmune diseases, including rheumatoid arthritis, hyper- and hypothyroidism, multiple sclerosis, and red cell aplasia. Other inherited diseases, including Alport syndrome, congenital defects, and inborn errors of metabolism were also found in the kindred. In the almost exclusively (99%) Old Colony Mennonite public health district in which the kindred was ascertained, there were multiple cases of Tourette syndrome, of malformations (including congenital heart defects and cleft lip +/- palate), and familial clusters of inborn errors of metabolism. We report this Old Colony (Chortitza) Mennonite isolate because 1) there are large familial aggregations of tissue-specific autoimmune diseases, malformations, inborn errors of metabolism, and of some other conditions whose genetic basis is still unknown; 2) there are multiple cases of rare genetic conditions, 3) we have established a computerized genealogic data base on over 1,000 kindred members as well as a cryopreserved lymphocyte/DNA bank on over 100 closely related individuals with various genetic conditions; and 4) this religious isolate, which extends across North, Central, and South America, offers an excellent opportunity for studying the epidemiology and molecular genetics of both common and rare inherited diseases.

Adrenal Hyperplasia, Congenital↗
PubMed2005

Development of projection-specific interneurons and projection neurons in the embryonic mouse and rat spinal cord.

Interneurons and projection neurons in the lumbar spinal cord of mouse and rat embryos were labeled retrogradely with fluorescent dextran amines from a distance of one segment from the segment of origin [lumbar segment (L) 2]. Six classes with specific axonal projections (ipsilateral ascending, descending, and bifurcating, and commissural ascending, descending, and bifurcating) were identified by differential labeling in both species and followed from embryonic day (E)12 to birth in the mouse. Neurons with shorter projections (intrasegmental interneurons) were not studied. We show that the four nonbifurcating neuron classes occupy characteristic, partially overlapping domains in the transverse plane, indicating a systematic pattern of migration and settlement related to axon trajectories. The number of neurons in each of the nonbifurcating classes increased steadily during development. Bifurcating neurons represented a minor fraction of the total throughout development and had relatively scattered positions within the ipsilateral and commissural neuron domains. Combination of retrograde tracing and immunohistochemistry for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) showed that none of the spinal neurons in the six projection-specific classes was GABA positive, suggesting that all GABA-positive spinal neurons, including previously described GABA-positive commissural neurons, are unlikely to have projections exceeding one or two segments in either direction.

Animals↗
PubMed1983

Developmental relationships between trigeminal ganglia and trigeminal motoneurons in chick embryos. III. Ganglion perikarya direct motor axon growth in the periphery.

The previous study in this series demonstrated that the ingrowth of the central axons of the trigeminal (V) ganglion is prerequisite to V motor axon outgrowth and somatic translocation. In the present experiment we determined whether further interactions with V ganglion cell bodies were required by V motoneurons after the V ganglion innervates the brainstem. Soon after the ganglion axons had penetrated the brainstem they were severed, and a barrier, either permeable or impermeable, was placed between the ganglion cell bodies and the metencephalon. V motor axons grew along aberrant pathways to circumvent the impermeable barriers, many rerouting to reach the V ganglion. Only those V motor nerves which contacted the V ganglion distal to the barrier reached their target musculature in the mandible. The pattern of migration of V motoneurons was normal regardless of the V motor nerve trajectory, but the cell bodies of those axons which did not reach a muscle were not fully differentiated. When permeable barriers (Millipore filters) were implanted, the nerves followed two types of trajectories. If the pore size of the filter was small (0.45 and 0.025 microns), the V motor nerves grew identically to those observed in embryos in which impermeable barriers had been implanted. If the pore size of the filter was large (8.0 and 0.08 microns), the V motor nerve grew along its normal path directly to the barrier. Small axonal bundles from these nerves frequently grew into the filter toward the distal V ganglion. These results indicate that V motor axons preferentially grow to the V ganglion perikarya after exiting from the brainstem. Contact with the V ganglion always results in V motor nerve growth to the mandible while growth of the V motor axons to aberrant target sites only occurs when the axons fail to contact the V ganglion cells distal to the barrier.

Animals↗
PubMed1997

Ancient and modern mitochondrial DNA sequences and the colonization of the Pacific.

Mitochondrial DNA (mtDNA) is a valuable tool for the study of recent human evolution because it is easy to analyse, is inherited uniparentally and has a relatively rapid rate of evolution. mtDNA analysis has been used extensively for the elucidation of the pattern of migrations of human populations. Several studies have focused on the Pacific because Polynesia was settled by humans for the first time relatively recently and there is a wealth of archaeological and linguistic data to complement genetic data on the region. Results of mtDNA analyses on modern-day Pacific populations indicate reduced genetic variability, and suggest that the Polynesians descend from people who migrated relatively recently from island Southeast Asia and that a population bottleneck occurred during the settlement of the central Pacific. Several informative polymorphisms have been identified in the hypervariable control region of mtDNA in modern-day Pacific populations that are helpful in tracing the ancestral affinities of these people. Studies of these mtDNA polymorphisms in ancient bones of prehistoric Pacific islanders indicate that the proto-Polynesian colonizers may have descended from the early settlers of island Melanesia. Although fraught with technical difficulties, studies of ancient DNA can provide valuable evidence on the genetic affinities of past peoples.

Asia↗
PubMed1975

Cellular immune reactivity in vitro and tumor rejection provided by tumor-associated antigens of friend-virus-induced leukemia.

Cell-mediated immunity (CMI) and tumor rejection were studied in the Friend virus leukemia system of C57Bl/6 mice. Mice were immunized with Friend leukemia virus (FLV) or X-irradiated FBL-3 leukemic cells and studied temporally for the development of CMI reactivity by assays of 51Cr release lymphocyte cytotoxicity, lymphocyte transformation, migration inhibition, Winn tumor cell neutralization and transplantation rejection. High levels of specific lymphocyte cytotoxicity were observed by day 7 f0llowing FLV infection; this reactivity reached a peak between 17 and 21 days, and returned to background levels by day 36. Further, positive Winn assays were obtained with spleen cells from mice immunized with FLV at times when the mice resisted live FBL-3 tumor challenge. Positive lymphocyte transformation was obtained with spleen cells from mice immunized with FLV or FBL-3, but not with cells from normal mice or mice immune to a syngeneic methycholanthrene-induced tumor, when cultured with papain-soluble FBL-3 or RBL-5 tumor-cell extracts or mitomycin-C (MMC)-treated FBL-3 or RBL-5 cells. Positive reactivity in the lymphocyte transformation assay occurred after reactivity had peaked in the lymphocyte cytotoxicity test. Similar positive macrophage migration inhibition patterns were also obtained with peritoneal exudate cells (PEC) from FLV-immunized mice using papain-solubilized tumor-associated antigen (TAA) from FBL-3 cells. These data suggest that sequential development and modulation of CMI reactivity occurs as observed in different assays following immunization in this system.

Animals↗