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H Repo

Publications and source records attributed to H Repo.

85 records · Page 5Linked to original sources
PubMed1981

Defective neutrophil migration in monosomy-7.

The migration in vitro of neutrophils from six patients with monosomy-7 or partial deletion of the long arm of chromosome 7 was studied by two methods: the Millipore filter assay and the migration under agarose assay. Four of the patients had preleukemia, one had subacute myelomonocytic leukemia, and one polycythemia vera. In four patients, chemotaxis (migration towards a higher concentration of chemoattractant) and chemokinesis (stimulated migration without a gradient) were shown to be defective by both methods. In the remaining two patients, this defect could be demonstrated only by the Millipore filter assay or by the agarose assay. Under agarose, random locomotion (no chemoattractant present) of the patients' neutrophils was less than that of the control subjects in four patients, whereas no clear difference could be shown by the Millipore filter method. This study demonstrates that the previously described defect of neutrophil migration in monosomy-7 involves not only chemotaxis but all stimulated migration and, at least in some patients, random locomotion as well. Defective migration in two patients with an apparently terminal deletion of the long arm of one chromosome 7 indicates that the distal half of 7q carries genetic material important for neutrophil locomotion.

Adolescent↗
PubMed1980

Chemotaxis in yersinia arthritis. HLA-B27 positive neutrophils show high stimulated motility in vitro.

Chemotaxis, chemokinesis, and spontaneous locomotion of polymorphonuclear leukocytes (PMNs) of yersinia arthritis (YA) patients and healthy subjects with or without HLA-B27 were studied by agarose assay and membrane filter technique. HLA-B27 positive healthy control subjects and yersinia patients showed significantly higher response to chemotactic stimulus than HLA-B27 negative controls. Consequently, the high response was associated with HLA-B27 irrespective of YA. The high responder PMNs may contribute to the more severe inflammatory symptoms in YA patients with HLA-B27.

Acute Disease↗
PubMed1980

Cellular hypersensitivity to tuberculin in BCG-revaccinated persons studied by skin reactivity, leucocyte migration inhibition and lymphocyte proliferation.

Some persons seem to lose long-standing peripheral hypersensitivity to tuberculin earlier than others. This was seen in a group of five healthy student nurses who had been BCG-vaccinated as children and were found, in routine skin testing, to be negative to 100 TU of tuberculin purified protein derivative (PPD). They were revaccinated, which resulted in conversion to 10 TU skin test positivity. In agreement with this, their buffy coat cells achieved reactivity to 100 microgram/ml of PPD in a leucocyte migration inhibitory factor (LIF) assay. However, the LIF response, being maximal at 4 weeks, faded away earlier than skin reactivity. Peripheral blood lymphocyte proliferation was studied with several PPD concentrations, 10 microgram/ml always inducing the maximum 3H-thymidine uptake. This was still high at 6 months after vaccination, when the skin reactions tended to be smaller than earlier. The reason why the various parameters of cellular hypersensitivity followed different courses is not known, but it may involve different subpopulations of lymphocytes, activity of suppressor cells or influence by serum factors such as mycobacterial antigen-antibody complexes.

Adolescent↗
PubMed1980

Leucocyte motility in the newborn: determination of spontaneous movement is essential in the in vitro assessment of neutrophil chemotaxis.

Polymorphonuclear leucocytes (PMNs) of the newborn show poor movement in vitro toward a chemotactic stimulus, such as zymosan-activated human serum (ZAS). This may result from a defect either in spontaneous movement or in the response of the cells to the stimulus. To identify the defect we studied chemotaxis, chemokinesis and spontaneous movement of cord blood PMNs by agarose assay and by the leading front modification of the Boyden chamber technique. Under agarose, cord PMNs showed much spontaneous movement. This, associated with poor stimulated movement, indicated a defect in the responsiveness of cord PMNs to ZAS. In the membrane filter, cord PMNs migrated spontaneously, and in the presence of ZAS, significantly less than adult cells. The weak spontaneous movement most probably resulted from poor deformability of cord PMNs and contributed to the weak stimulated movement of these cells in the filter. Our results indicate that the impaired chemotaxis was due to a defect in both responsiveness and deformability of cord PMNs rather than to a defect in their intrinsic ability to move.

Adult↗
PubMed1979

Impaired neutrophil chemotaxis in Pelger-Huët anomaly.

A family has previously been described in which four members with Pelger-Huët (P-H) anomaly suffered from recurrent attacks of abdominal pain and fever, while one member, whose polymorphonuclear leucocytes (PMNs) were also hyposegmented, was asymptomatic. We studied chemotaxis, chemokinesis and spontaneous locomotion of PMNs in the three surviving symptomatic sisters, in their asymptomatic brother and in two asymptomatic members of another family with P-H anomaly. The spontaneous migration of the PMNs of the three sisters was significantly slower both under agarose and in a membrane filter than that of the PMNs of the asymptomatic patients with P-H anomaly. Chemotactic and chemokinetic locomotion of the PMNs of the symptomatic sisters was also slow. Our results suggests that the impaired chemotaxis was due to a defect in the intrinsic locomotor capacity of PMNs rather than in their deformability or their responsiveness to the chemotactic stimulus.

Adult↗
PubMed1978

Use of leucocyte migration under agarose to study spontaneous and directed locomotion of leucocytes.

Three different cell attractants, together with the parallel use of the leucocyte migration agarose test (LMAT) and the leading front modification (LFM) of the Boyden chamber technique, were employed in studying whether the maximal migration of normal human polymorphonuclear leucocytes (PMNs) is higher toward an attractant (chemotaxis) than in the same attractant incorporated in the culture media (chemokinesis). Using LMAT, the maximal migration distance toward zymosan activated serum (ZAS) was found to be significantly longer than that under agarose mixed with ZAS, thus indicating a chemotactic effect exerted by ZAS. When bacterial culture filtrate (BCF) and casein were used as attractants, the corresponding difference was not significant, implying that the stimulatory effect of these substances on cell migration could be explained by increased random locomotion (chemokinesis) alone. In LFM, the migration rate was significantly higher along a casein gradient than without a gradient. Using ZAS, however, only chemokinesis could be demonstrated. BCF was found to attract PMNs into membrane filters only in the presence of human serum albumin. These observations give credence to the view that both LMAT and LFM are applicable to the in vitro assessment of chemotaxis and chemokinesis but the attractant of choice for this is different in each of the two methods.

Caseins↗
PubMed1977

Leukocyte migration agarose test for the assessment of human neutrophil chemotaxis. I. Effects of environmental factors on neutrophil migration under agarose.

To apply the leukocyte migration agarose test (LMAT) to the in vitro assessment of human neutrophil chemotaxis, effects of different culture conditions on neutrophil migration under agarose were studied. Presence of either serum or human serum albumin (HSA) in the culture medium was necessary for detectable neutrophil migration. HSA was preferred since heat-stabile chemotactic agents were found to be generated from fresh serum in the presence of agarose. Additional CO2 in the assay milieu could be replaced by decreasing the NaHCO3 concentration of the culture medium. Both the directed and the spontaneous migration rates of neutrophil leukocytes increased when the concentration of agarose was decreased. Area and distance of migration and cumulative cell count of migrated neutrophil leukocytes were suitable for quantitating the neutrophil migration rate.

Adult↗
PubMed1977

Leukocyte migration agarose test for the assessment of human neutrophil chemotaxis. II. Variables in the attraction assay.

Optimal conditions for the attraction assay of human neutrophil leukocytes were studied, using the leukocyte migration agarose test (LMAT). Larger migration areas were obtained toward the attractant wells when they were filled with zymosan-activiated serum (ZAS) in advance than when both the attractant and the cells were added simultaneously. Chemotactic indices (CI; the ratio between the migration rate toward attractant and that toward the control substance) decreased when the number of applied neutrophil leukocytes increased, whereas migration differentials (MD; the difference between the migration rate toward attractant and that toward the control substance) were not markedly affected. Both the spontaneous and the directed migration rates, and CI and MD of neutrophil leukocytes obtained from the same donor on different days varied markedly. When tested repeatedly, however, the neutrophil leukocytes of different donors migrated on the average rather equally toward inactivated serum, as they also did toward ZAS, and the variation of the means of CI and MD was insignificant.

Adult↗
PubMedDate not supplied

Whole blood luminol-enhanced chemiluminescence: statistical analysis of the responses of different subjects.

Whole blood luminol-enhanced chemiluminescence (CL) was studied using N-formyl-methionyl-leucyl-phenylalanine (FMLP) or opsonized zymosan particles as stimuli. The peak and the integral responses of CL were recorded. In the FMLP-induced CL the initial activation (1-minute values) was also studied, because it coincides with the extracellular production of oxy radicals. Correction factors based on neutrophil count and on haemoglobin concentration were found to decrease dispersion and shape the distributions of the CL responses close to normal in a study of 50 healthy adults. One-minute values were significantly lower in women than in men but there were no significant differences for peak or integral values between sexes. Depressed reaction is in accordance with the previous findings that phagocytic oxy radical production is depressed in female plasma. Thus, our results suggest that 1-minute value is a variable more sensitive than peak or integral value of the CL response.

Adult↗
PubMedDate not supplied

Effects of HLA-B27 positive and negative sera on migration of polymorphonuclear leukocytes in vitro.

Sera from both HLA-B27 positive patients with previous yersinia arthritis and healthy HLA-B27 positive subjects have been reported to stimulate chemokinetic migration of polymorphonuclear leukocytes (PMNs) more than sera from subjects who are HLA-B27 negative. To study this further we tested chemotactic and chemokinetic activities of sera of 213 consecutive blood donors (27 positive for HLA-B27, 12.7%) and those of 55 children (mean age 20 months, range 6-137 months, 8 positive for HLA-B27, 14.5%). Migration distances of PMNs both in membrane filter and under agarose were longer, although not in a statistically significant way, in HLA-B27 positive adult sera than in HLA-B27 negative ones. Chemokinetic activity of sera of HLA-B27 positive children was very similar to that of HLA-B27 negative children. These results give credence to the view that PMN migration enhancing capacity of HLA-B27 positive sera described previously is acquired secondarily and is not genetically determined.

Adult↗