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PubMed1988

Subpopulations of T lymphocytes emigrating in venous blood draining pig thymus labelled in vivo with fluorochrome.

The emigration of labelled thymus cells in the pig was studied directly in blood draining the large right distal cervical lobe of the thymus after controlled labelling with FITC delivered through cannulated branches of a main thymic artery and vein by temporary ex vivo perfusion at body temperature. Roughly 1% of thymic cells emigrated per day. Unlike most thymocytes, which are small, the size spectrum of thymic emigrants is slightly larger than that of typical blood lymphocytes. Surface-marker studies show that the surface phenotypes of the emigrants differ from both typical thymus and peripheral blood lymphocytes. Although the emigrants resemble thymocytes in the high proportion of strong rosettes formed with sheep red blood cells (RBC), they rosette poorly with pig red cells, particularly in the unenhanced saline test, in this respect behaving like blood lymphocytes. The peripheral T-cell subset bearing a Fc receptor is almost absent in thymus, but is well represented among the emigrants which thus resemble corticosteroid-resistant thymocytes in the pig. The large population of thymus-dependent Null lymphocytes in young pig blood apparently arise in thymus since they constitute 1/3 of emigrants, although only forming less than 10% of thymus cells. This emigration of thymic cells is discussed in relation to its implications for the turnover of known functional peripheral T-cell populations.

Animals↗
PubMed2001

Longitudinal study of psychiatric symptoms, disability, mortality, and emigration among Bosnian refugees.

CONTEXT: Evidence is emerging that psychiatric disorders are common in populations affected by mass violence. Previously, we found associations among depression, posttraumatic stress disorder (PTSD), and disability in a Bosnian refugee cohort. OBJECTIVE: To investigate whether previously observed associations continue over time and are associated with mortality emigration to another region. DESIGN, SETTING, AND PARTICIPANTS: Three-year follow-up study conducted in 1999 among 534 adult Bosnian refugees originally living in a refugee camp in Croatia. At follow-up, 376 (70.4%) remained living in the region, 39 (7.3%) were deceased, 114 (21.3%) had emigrated, and 5 (1%) were lost to follow-up. Those still living in the region and the families of the deceased were reinterviewed (77.7% of the original participants). MAIN OUTCOME MEASURES: Depression and PTSD diagnoses, based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria and measured by the Hopkins Symptom Checklist-25 and the Harvard Trauma Questionnaire, respectively; disability, measured by the Medical Outcomes Study Short-Form 20; and cause of death, determined by family interviews with review of death certificates, if available. RESULTS: In 1999, 45% of the original respondents who met the DSM-IV criteria for depression, PTSD, or both continued to have these disorders and 16% of respondents who were asymptomatic in 1996 developed 1 or both disorders. Forty-six percent of those who initially met disability criteria remained disabled. Log-linear analysis revealed that disability and psychiatric disorder were related at both times. Male sex, isolation from family, and older age were associated with increased mortality after adjusting for demographic characteristics, trauma history, and health status (for male sex, adjusted odds ratio [OR], 2.63; 95% confidence interval [CI], 1.17-5.92; living alone, OR, 2.40; 95% CI, 1.07-5.38; and each 10-year increase in age, OR, 1.91; 95% CI, 1.34-2.71). Depression was associated with higher mortality in unadjusted analysis but was not after statistical adjustment (unadjusted OR, 3.12; 95% CI, 1.55-6.26; adjusted OR, 1.85; 95% CI, 0.82-4.16). Posttraumatic stress disorder was not associated with mortality or emigration. Spending less than 12 months in the refugee camp (OR, 11.30; 95% CI, 6.55-19.50), experiencing 6 or more trauma events (OR, 3.34; 95% CI, 1.89-5.91), having higher education (OR, 1.90; 95% CI, 1.10-3.29), and not having an observed handicap (OR, 0.11; 95% CI, 0.02-0.52) were associated with higher likelihood of emigration. Depression was not associated with emigration status. CONCLUSIONS: Former Bosnian refugees who remained living in the region continued to exhibit psychiatric disorder and disability 3 years after initial assessment. Social isolation, male sex, and older age were associated with mortality. Healthier, better educated refugees were more likely to emigrate. Further research is necessary to understand the associations among depression, emigration status, and mortality over time.

Adult↗
PubMed1992

[Introduction of shock therapy and psychiatric emigration].

The introduction and general acceptance of shock treatment was intimately connected with the emigration of psychiatrists from the German speaking countries in 1933-1938. In 1934 Manfred Sakel began in Vienna, possibly already in 1933 in Berlin, with insulin shock treatment, and later emigrated to the US. From 1936 Max Müller in Münsingen, Switzerland, practised and propagated the same treatment. Many psychiatric emigrants, on their way to their new countries, visited Münsingen to learn the methods and take them to their future countries of residence (e.g. Lucie Jessner, Gertrude May-Gross, Martin Gross, Ruth Wilmanns, Arthur Kronfeld, Justin Hans Adler and Jacob Peter Frostig). In 1934 Ladislas von Meduna, who emigrated to Chicago in 1939, using campher and Cardiazol also introduced the convulsion treatment. After Cerletti and Bini in Rome had changed the method of provoking convulsions by using electric current, other psychiatric emigrants (Lothar Kalinowsky, Fritz Kant, William Karlinger, Lilly Ottenheimer, Max Rinkel, among others) introduced this method to many countries. In addition, Wagner-Jauregg's best known collaborators for the well-introduced malaria therapy, also had to emigrate. Among these are Helene Deutsch, Josef Gerstmann, Bernhard Dattner and Martha Brünner-Ornstein. The review of life and work of the psychiatrists concerned, before and after emigration, has been complemented by unpublished material.

Convulsive Therapy↗
PubMed1990

Using census and survey data to measure undocumented immigration and emigration for the United States.

The estimation of emigration and undocumented immigration rates for the United States is discussed. "A residual methodology compares census or survey data on the resident foreign-born population with an independently derived estimate of the legally resident foreign-born population. The difference is the estimated undocumented population which may be compared for alternative dates to derive measures of change. In 1988, this difference was 1.9 million, similar to the 1980 estimate of 2.1 million.... Measurement of emigration...has recently relied on resident reports of immediate relatives who have emigrated. Controlling for multiple reporting of the same emigrants, the direct estimate of the emigrant population from the United States is about 1.2 million. Allowing for undercoverage of the emigrant population due to nonresident relatives, there could be 2.0 million or more emigrants."

Americas↗
PubMed1977

Emigration and remigration of Okinawans settled in the lowlands of eastern Bolivia in relation to background characteristics of their place of origin.

Post-war Okinawans emigrated to the lowlands of Bolivia in an attempt of pioneer agricultural colonization were studied with regard to behavioral patterns of the adjustment process in terms of permanency in the newly created colony. The uniqueness of the post-war emigration to Bolivia by Okinawans is discussed in comparison with pre-war emigration and the inter-regional migratory flow. The permanency of Okinawan emigrants in Bolivia is analyzed in relation to background characteristics of their regional origin in Okinawa using Spearman's rank correlations between each pair of selected variables; the number of emigrants by municipality in Okinawa Prefecture, rate of persons who settled in the colony, rate of population engaged in the primary sector of economy in 1965 in Okinawa Prefecture, and rate of area for U.S. military use. The permanency of the migrants in colonization is related to the background characteristics in the place of their origin before emigration. The likelihood of emigrants settling in the colony is thus greater for those from less urbanized municipalities, the size of migrants from one municipality of the rural area signifying the permanency in the pioneer colonization project.

Bolivia↗
PubMed1998

Combinatorial requirements for adhesion molecules in mediating neutrophil emigration during bacterial peritonitis in mice.

To investigate the requirements for adhesion molecules in neutrophil emigration during peritonitis, mice received intraperitoneal injections of Streptococcus pneumoniae while the functions of multiple adhesion molecules were blocked. Emigration after 4 h was compromised by antibodies against ICAM-1 or genetic deficiency of ICAM-1. Anti-CD11a/CD18 antibodies decreased emigration in ICAM-1 mutant mice, suggesting that ICAM-1 independent emigration requires CD11/CD18 complexes. In contrast, mice mutant in ICAM-1 plus E-selectin showed no defect in emigration, suggesting that E-selectin commits neutrophils to an ICAM-1-dependent pathway during streptococcal peritonitis. However, in mutant mice lacking the three endothelial adhesion molecules E-selectin, P-selectin, and ICAM-1, emigration after 4 h was significantly compromised. Thus, P-selectin is essential to ICAM-1- and E-selectin-independent acute peritoneal inflammation. After 24 h of peritonitis, there were no differences between WT and E-selectin/P-selectin/ICAM-1 mutant mice, demonstrating that these endothelial adhesion molecules are not essential to neutrophil emigration during later stages of peritonitis.

Animals↗
PubMed2004

Queen movement during colony emigration in the facultatively polygynous ant Pachycondyla obscuricornis.

In ants, nest relocations are frequent but nevertheless perilous, especially for the reproductive caste. During emigrations, queens are exposed to predation and face the risk of becoming lost. Therefore the optimal strategy should be to move the queen(s) swiftly to a better location, while maintaining maximum worker protection at all times in the new and old nests. The timing of that event is a crucial strategic issue for the colony and may depend on queen number. In monogynous colonies, the queen is vital for colony survival, whereas in polygynous colonies a queen is less essential, if not dispensable. We tested the null hypothesis that queen movement occurs at random within the sequence of emigration events in both monogynous and polygynous colonies of the ponerine ant Pachycondyla obscuricornis. Our study, based on 16 monogynous and 16 polygynous colony emigrations, demonstrates for the first time that regardless of the number of queens per colony, the emigration serial number of a queen occurs in the middle of all emigration events and adult ant emigration events, but not during brood transport events. It therefore appears that the number of workers in both nests plays an essential role in the timing of queen movement. Our results correspond to a robust colony-level strategy since queen emigration is related neither to colony size nor to queen number. Such an optimal strategy is characteristic of ant societies working as highly integrated units and represents a new instance of group-level adaptive behaviors in social insect colonies.

Animals↗
PubMed1997

Neutrophil emigration in the skin, lungs, and peritoneum: different requirements for CD11/CD18 revealed by CD18-deficient mice.

To determine the role of CD11/CD18 complexes in neutrophil emigration, inflammation was induced in the skin, lungs, or peritoneum of mutant mice deficient in CD18 (CD18-/- mutants). Peripheral blood of CD18-/- mutants contained 11-fold more neutrophils than did blood of wild-type (WT) mice. During irritant dermatitis induced by topical application of croton oil, the number of emigrated neutrophils in histological sections of dermis was 98% less in CD18-/- mutants than in WT mice. During Streptococcus pneumoniae pneumonia, neutrophil emigration in CD18-/- mutants was not reduced. These data are consistent with expectations based on studies using blocking antibodies to inhibit CD11/CD18 complexes, and on observations of humans lacking CD11/CD18 complexes. The number of emigrated neutrophils in lung sections during Escherichia coli pneumonia, or in peritoneal lavage fluid after 4 h of S. pneumoniae peritonitis, was not reduced in CD18-/- mutants, but rather was greater than the WT values (240 +/- 30 and 220 +/- 30% WT, respectively). Also, there was no inhibition of neutrophil emigration during sterile peritonitis induced by intraperitoneal injection of thioglycollate (90 +/- 20% WT). These data contrast with expectations. Whereas CD11/CD18 complexes are essential to the dermal emigration of neutrophils during acute dermatitis, CD18-/- mutant mice demonstrate surprising alternative pathways for neutrophil emigration during pneumonia or peritonitis.

Animals↗
PubMed2004

Ventrally emigrating neural tube (VENT) cells: a second neural tube-derived cell population.

Two embryological fates for cells of the neural tube are well established. Cells from the dorsal part of the developing neural tube emigrate and become neural crest cells, which in turn contribute to the development of the peripheral nervous system and a variety of non-neural structures. Other neural tube cells form the neurons and glial cells of the central nervous system (CNS). This has led to the neural crest being treated as the sole neural tube-derived emigrating cell population, with the remaining neural tube cells assumed to be restricted to forming the CNS. However, this restriction has not been tested fully. Our investigations of chick, quail and duck embryos utilizing a variety of different labelling techniques (DiI, LacZ, GFP and quail chimera) demonstrate the existence of a second neural tube-derived emigrating cell population. These cells originate from the ventral part of the cranial neural tube, emigrate at the exit/entry site of the cranial nerves, migrate in association with the nerves and populate their target tissues. On the basis of its site of origin and route of migration we have named this cell population the ventrally emigrating neural tube (VENT) cells. VENT cells also differ from neural crest cells in that they emigrate considerably after the emigration of neural crest cells, and lack expression of the neural crest cell antigen HNK-1. VENT cells are multipotent, differentiating into cell types belonging to all four basic tissues in the body: the nerve, muscle, connective and epithelium. Thus, the neural tube provides at least two cell populations--neural crest and VENT cells--that contribute to the development of the peripheral nervous system and various non-neural structures. This review describes the origin of the idea of VENT cells, and discusses evidence for their existence and subsequent fates.

Animals↗
PubMed2006

Upper urothelial tumors in emigrants from Balkan endemic nephropathy areas in Serbia.

AIM: The aim of the study was to investigate upper urothelial tumors (UUT) in emigrants from Balkan endemic nephropathy (BEN) areas in Serbia and compare them with UUT from both endemic and nonendemic areas. MATERIALS AND METHODS: A total of 1,121 patients from the state cancer database, between 1960 and 1998, were investigated. Sixty of them were emigrants from BEN areas. RESULTS: UUT in emigrants from BEN areas occurred after 21.7+/-9.9 years (median 20) spent in a rural environment. The time spent outside of the BEN regions was 33.2+/-12.8 years (median 31, range 10-72). Age at surgery was 55 years (range 31-89). In emigrants from BEN areas, there was a significant association of other diseases with UUT: renal failure in 63%, bladder tumors in 23.3% and bilateralism in 6.7% of the patients. Bilateralism was statistically more frequent in emigrants from BEN areas (p=0.04), as were low-grade tumors (p=0.03). There was no statistical difference in tumor stage between patients from BEN areas and from outside of them. Relatives of the emigrants from BEN areas were also affected by BEN, UUT and both of them (33%). CONCLUSIONS: It is concluded that hereditary as well as environmental factors are important for the expression and evolution of the disease. An early period of life spent in the endemic region seems important for the later development of UUT in emigrants from BEN regions. Different time spans spent in the endemic region have no effect on the age of appearance of UUT.

Adolescent↗
PubMed2006

Two waves of neutrophil emigration in response to corneal epithelial abrasion: distinct adhesion molecule requirements.

PURPOSE: Corneal abrasion results in an inflammatory response characterized by leukocyte emigration into the corneal stroma. Adhesion molecules play a critical role in leukocyte emigration to wound sites, but differences are evident in different vascular beds. In this study, the contributions of two families of adhesion molecules to neutrophil emigration into the cornea were investigated. METHODS: Re-epithelialization, patterns of neutrophil influx and CXC chemokine production were assessed in C57Bl/6 mice after removal of a 2-mm diameter area of central corneal epithelium. Comparisons were made between wild-type (WT) mice and mice with targeted deletions of genes for CD18 (CD18(-/-)) or P- and E-selectin (P/E-sel(-/-)) or in mice with antibody-induced neutropenia. RESULTS: Wild-type mice exhibited neutrophil emigration in two waves, the first peaking at 18 hours and the second at 30 hours after wounding, 6 hours after epithelial wound closure and peak levels of corneal CXCL1. In CD18(-/-) animals, only a single wave of neutrophil influx was seen, and it was temporally and quantitatively equivalent to the second wave in WT. In P/E-sel(-/-) mice, neutrophil influx was markedly depressed throughout the 48-hour observation period. Re-epithelialization was significantly delayed in mice with adhesion molecule deletions and in neutropenic animals. Transfer of wild-type leukocytes into CD18(-/-) mice resulted in neutrophil emigration into the injured cornea within 18 hours of wounding and improved closure of the epithelium. CONCLUSIONS: Neutrophil emigration into corneal stroma after epithelial abrasion occurs in two waves. The first is dependent on CD18 integrins and selectins, whereas the second is CD18-independent but requires selectins. Early leukocyte emigration appears to promote re-epithelialization.

Animals↗
PubMed1998

Intraspecific variation in the effects of mating on emigration activity and fecundity in a natural population of Drosophila melanogaster.

Intraspecific variation in the effects of mating on the emigration response behavior and fecundity of Drosophila melanogaster was investigated using isofemale lines of the Himeji population in Japan. The emigration activities of the mated and unmated females were examined with Sakai's population system. The isofemale lines were classified into two groups with respect to the effect of mating on emigration activity; 1) copulation decreased the emigration activity in 26 out of 28 isofemale lines, and 2) higher emigration activity was noted in the mated than in the unmated females in two lines. The percentage of expressed genotypic variance on emigration activity was higher in the unmated females than in the mated ones. Gregarious oviposition did not seem to be related to the decrease of emigration activity in the mated females.

Animals↗
PubMed1992

Quantitative genetic study on sexual difference in emigration behavior of Drosophila melanogaster in a natural population.

A quantitative genetic analysis was conducted on emigration response behavior using 140 second chromosome lines of Drosophila melanogaster. Fourteen sets of 5 x 5 partial diallel cross experiments were made in the parental generation. The emigration activity per batch of 50 male and 50 female F1 progeny was scored with Sakai's population system. Sexual difference did not appear in the emigration activity in these experiments. A significant genotype x sex x set interaction was detected. The genetic variance components of emigration activity differed between sexes: In males, additive genetic variance of emigration activity was 0.0497 +/- 0.0092 and dominance variance, 0.0018 +/- 0.0046; in females, additive, 0.0373 +/- 0.0076 and dominance, 0.0169 +/- 0.0044. Additive genetic correlation between sexes for the emigration activity was 0.685 +/- 0.150, deviating significantly from unity. These results suggested that the genes affecting emigration activity would operate differently between sexes of D. melanogaster in natural populations.

Animals↗
PubMed1994

Survivors of bursal B cell production and emigration.

The bursa of Fabricius is the site of primary B cell generation in the chicken. Analysis of the rate of bursal cell emigration demonstrated that about 1% of the blood B cell pool was replaced per hour by bursal emigrants. Surgical bursectomy distinguished three populations of blood B cells. About 60% of blood B cells in 3-wk-old chickens were short lived, with a lifespan of 2 to 3 d, and included most bursal emigrants. These cells migrate directly from the bursal follicular cortex to the periphery, express the LT2 antigen, and are proposed to represent a diversified repertoire of B cell specificities that have emigrated from the bursa in the absence of interaction with environmentally derived antigens in the follicular medulla. About 35% of blood B cells were much longer lived cells, having a lifespan exceeding 2 wk. These cells represent about 10% of bursal emigrants, which do not express the LT2 antigen and do not divide in the peripheral blood following emigration from the bursa. This population may represent cells that have undergone positive selection in the bursa by interacting with environmentally derived antigens and should, therefore, contain a restricted repertoire of B cell specificities. The third population, about 5% of blood B cells, were short-lived cells that represent the progeny of postbursal B cell production. The frequency of these cells progressively increases with time, taking over from the short-lived bursal emigrants as the bursa involutes, likely as a diversified repertoire of B cell specificities.

Animals↗
PubMed2000

Host choice and host leaving in Rhopalosiphum padi (Hemiptera: aphididae) emigrants and repellency of aphid colonies on the winter host.

Host choice and winter-host leaving in emigrants of bird cherry-oat aphid, Rhopalosiphum padi (Linnaeus), were investigated in the laboratory. In settling choice tests, emigrants collected from the winter host, Prunus padus, preferred this plant over a summer host, oats. Emigrants which had left P. padus for up to 24 h did not express a preference as a group, and those which had left for 24-48 h preferred oats. Eighty seven percent of emigrants caged as fourth-instar nymphs on P. padus leaves abandoned the host by the second day of adult life, and apparently did not subsequently return to the leaf. In an olfactometer, P. padus leaves which had supported spring generations of R. padi were repellent to emigrants. Volatiles were entrained from uninfested and R. padi-infested P. padus using cut twigs in the laboratory as well as intact twigs on a tree in the field. Entrainment extracts from uninfested P. padus had no effect on emigrants in the olfactometer, whereas those from twigs infested with nymphal emigrants were repellent. The study indicates that in R. padi, host-alternation is driven by behavioural changes which occur in individuals as well as between morphs.

Animals↗
PubMed1990

Streptococcus pneumoniae-stimulated macrophages induce neutrophils to emigrate by a CD18-independent mechanism of adherence.

Neutrophil adherence to and emigration across endothelium are in large part dependent upon the neutrophil membrane CD11/CD18 glycoprotein complex. Recently, however, we have demonstrated that some stimuli can elicit neutrophil emigration in the lung by a CD18-independent pathway. We examined further the mechanism involved in CD18-independent emigration in a rabbit model of inflamed peritoneum. Neutrophil emigration in the peritoneum induced by instillation of E. coli and S. pneumoniae was studied under four experimental conditions: Group 1--normal peritoneum, Group 2--peritoneum primed with protease peptone to increase the number of macrophages, Group 3--peritoneum treated by protease peptone instillation and then depleted of the increased macrophage population, and Group 4--peritoneum with macrophages transplanted from animals enriched as in Group 2. Experiments were run in pairs with animals in each group assigned to receive either saline (control) or monoclonal antibody (MAb) 60.3 prior to bacterial instillation in the peritoneum. Neutrophil emigration in response to E. coli was greater than 86% inhibited by MAb 60.3 in both the normal and the macrophage-enriched peritoneum. Neutrophil emigration in response to S. pneumoniae was inhibited greater than 85% in the normal peritoneum and the macrophage-enriched and the transplanted macrophage peritoneum. These data indicate that macrophages can augment PMN emigration by a non-CD18 mechanism, and may explain the increased sensitivity of organs with large resident macrophage populations, liver and lung, to injury following shock and sepsis.

Animals↗
PubMed1986

Numbers and phenotype of lymphocytes emigrating from sheep bone marrow after in situ labelling with fluorescein isothiocyanate.

In normal young lambs the bone marrow was selectively labelled with fluorescein isothiocyanate by a temporary perfusion of one hind-leg. One day later, the incidence of bone marrow emigrants in different lymph nodes, spleen, Peyer's patches, thymus, non-perfused bone marrow and blood was determined. The emigrants were also phenotyped by the use of monoclonal antibodies and classified into monocytes or lymphocyte subsets. Large numbers of lymphocytes left the bone marrow of the perfused leg during 1 day. Considerable numbers of cells migrated to other bone marrow compartments. Varying numbers of mononuclear emigrants were found in peripheral lymphoid organs, with labelling indices ranging from 1.06% in the blood to 0.004% in the thymus. In the spleen, comparable numbers of B- and T-lymphocyte emigrants from the bone marrow were found, whereas in the blood, lymph nodes and jejunal Peyer's patches many more emigrants were T lymphocytes than B lymphocytes. In the prescapular lymph nodes, for instance, 90.4% of emigrants were T cells but only 9.6% were B cells. Based on the large numbers of lymphocytes emigrating from the bone marrow, their phenotypes and their entry into other bone marrow compartments, it it can be concluded that the bone marrow of young lambs is an integral part of the migratory route of lymphocytes.

Animals↗
PubMed1986

Emigration and accumulation of PMN-leukocytes induced by endotoxin, interleukin 1 and other chemotactic substances.

This publication describes polymorphonuclear leukocyte (PMN) emigration and accumulation, which is prerequisite for their defensive function in infected tissues. The extravasated PMNs can kill microorganisms, but in this process they also release proteolytic enzymes and other cell constituents which can alter and even injure the tissues, primarily the microcirculation. In the first part of the paper in vivo quantitation of the acute inflammatory reaction is described with emphasis on PMN emigration and accumulation. With 51Cr-labeled PMNs the kinetics of their emigration induced by a number of chemotaxins and chemotaxinigens was found to be similar, peaking in 1-4 hour old lesions and returning to baseline values thereafter. The most potent substance tested was endotoxin, which induced a PMN influx at a molar concentration a least 3 orders of magnitude lower than the other substances tested, implying the these substances are not the primary endogenous mediators of endotoxin induced inflammation. Next we describe an observation which shed considerable light on the mechanisms underlying PMN emigration. When a chemotaxin or endotoxin was injected intradermally and after varying periods of time reinjected into the same site, the PMN influx into those sites was diminished, compared to sites not previously injected, i. e. injected for the first time. This tachyphylaxis or diminished responsiveness was attributed to a downregulation of receptors, presumably on endothelial cells, coupled to a facilitatory mechanism. Other mechanism proposed to terminate emigration of PMNs during inflammatory reaction were unlikely, based on our experimental findings. Endotoxin is not chemotactic in vitro but it induces PMN emigration when injected intradermally. Hence the third part of the publication deals with PMN emigration induced by interleukin 1 and its significance for endotoxin-induced inflammation. IL 1 is the only chemotaxin which induces PMN accumulation at a concentration comparable to that of endotoxin and considerably lower than the other chemotaxins. There was cross tachyphylaxis between endotoxin and IL 1 and vice versa. The PMN influx into IL 1 sites injected 6 hours earlier with IL 1 or with endotoxin was diminished compared to IL 1 sites injected into normal skin. Sites injected first with IL 1 and then with a low dose of endotoxin also exhibited cross tachyphylaxis. FMLP or LTB4 injected into sites pretreated with endotoxin did not exhibit cross tachyphylaxis, i. e. the PMN influx was similar to sites injected for the first time with these chemotaxins.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗