OBJECTIVETo determine the optimal method for separating neutrophils for studying neutrophil polarization.

METHODSHuman neutrophil was separated from healthy human peripheral blood by Percoll density gradient centrifugation and Dextran sedimentation. The cell polarization, purity and activity of the neutrophils were determined, and F-actin polymerization and [Ca2+]i were analyzed.

RESULTSNo significant difference was found in cell polarization, purity and activity of the human neutrophils separated by Dextran sedimentation and Percoll density gradient centrifugation (P>0.05), but F-actin polymerization was inhibited in PMNs separated by Dextran sedimentation, and the peak value of [Ca2+]i was decreased by 25% in PMNs separated by Dextran sedimentation compared to the cells separated by Percoll density gradient centrifugation.

CONCLUSIONSBoth Percoll density gradient centrifugation and Dextran sedimentation can be used for isolating human neutrophils to study cell polarization, but the former method allows better isolation. Dextran sedimentation can be considered when a large number of neutrophils need to be separated.

Actins ; Cell Polarity ; Cell Separation ; Centrifugation, Density Gradient ; methods ; Humans ; Leukocyte Count ; Neutrophils ; cytology ; Povidone ; Silicon Dioxide

OBJECTIVE: To explore the effects of exogenous transforming growth factor-beta 1 (TGFbeta1) on peripheral nerve regeneration after the peripheral nerve injury and if TGFbeta1 regulates the expression of basic fibroblast growth factor (bFGF) in the anterior horn motoneurons of spinal cord during regeneration. METHODS: Forty-eight rats were crushed on the right sciatic nerve and then randomly divided into 2 groups: TGFbeta1 group and NS group. In TGFbeta1 group, TGFbeta1 50 microL (0.1 microg/mL) was injected into the proximal nerve near to the crushed nerve and after the operation the injured leg was injected with equal TGFbeta1 whereas the NS was replaced in the NS group. The rats of each group survived for 3, 7, 14 and 21 days after the lesion. The bFGF expression in the anterior horn motoneurons of spinal cord was detected by immunohistochemistry (IHC). Semi-thin section and Fast Blue retrograde tracing were also performed with the rats surviving for 21 days to observe the regeneration of distal end in the injured right sciatic nerve. RESULTS: The number of bFGF immunoreactive positive motoneurons in TGFbeta1 group was obviously higher than that of the NS group (P < 0.05). In the distal sciatic nerve of the rats treated with TGFbeta1, the number and diameter of regenerating myelinated axons and the thickness of myelinated sheath were more than those of the NS group (P < 0.05). The number of motoneurons in spinal cord and neurons in dorsol root ganglia (DRG) labelled with Fast Blue in the NS group was obviously lower than in the TGFbeta1 group (P < 0.01). CONCLUSION Exogenous TGFbeta1 plays an important role in promoting the peripheral nerve regeneration; TGFbeta1 up-regulates the bFGF expression in the anterior horn motoneurons of spinal cord during the peripheral nerve regeneration.
Animals ; Female ; Fibroblast Growth Factor 2 ; biosynthesis ; genetics ; Male ; Motor Neurons ; metabolism ; Nerve Regeneration ; drug effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve ; injuries ; metabolism ; physiology ; Spinal Cord ; metabolism ; Transforming Growth Factor beta ; pharmacology ; Transforming Growth Factor beta1

Objective:To establish a graded method to avoid mean fluorescence intensity(MFI)threshold of HLA Class I antibodies corresponding antigen,and the HLAMatchmaker program has been used to select the minimum mismatch value of donor-patient epitopes.Evaluate the application value of combining both methods in selecting HLA compatible platelets(PTL)for patients with immune platelet transfusion failure(IPTR)in improving platelet the corrected count increment(CCI).Methods:A total 7 807 PLT cross-matching compatible were performed by the solid-phase red cell adherence(SPRCA)method for 51 IPTR patients.The Luminex single antigen flow cytometry was used to detect HLA Class I antibodies in patients,and detected the MFI value for different specificity antigens of HLA Class I antibodies,was graded into strong positive group(MFI＞4 000,level 1),medium positive group(1 000＜MFI 4 000,2),weak positive group(500＜MFI≤1 000,3),and one negative control group(MFI≤500).The results of 7 807 SPRCA their negative/positive reaction wells were enrolled and statistically analyzed in different grades and the four groups,the statistical differences between the four groups were compared.Multiple applications for the select HLA Class I compatible donor events were made for patients in two cases,and HLAMatchmaker program was used to calculate the number of HLA Class I epitopes mismatches between the donors and patients.The donor with the minimum number of epitopes mismatches was selected,while avoiding the corresponding antigens of HLA Class I antibodies in levels 1 and 2,the provision of HLA compatible platelets for IPTR.After the transfusions,the CCI value of the platelet transfusion efficacy evaluation index was calculated,and the clinical evaluation of the transfusion effect was obtained through statistical analysis.Results:There were statistically significant differences in the positive results of SPRCA immunoassay among the strong positive group,medium positive group,and weak positive group of 51 IPTR patients with different specific of HLA-I class antibodies and corresponding antigens(all P＜0.001).The positive results showed a range from high to low,with strong positive group＞medium positive group＞weak positive group.There were a statistical difference among between the strongly positive or moderately positive groups and the negative control group(P＜0.001).There was no statistical difference between the weakly positive group and the negative control group(P＞0.05).The strong positive group was set as the corresponding specific HLA Class I site corresponding antigen grade 1 avoidance threshold,the medium positive group as the grade 2 avoidance thresholds,and the weak positive group as the grade 3 avoidance threshold.In the case of donor platelet shortage,it is not necessary to avoid the weak positive group.Avoiding the strategy of donor antigens and HLAMatchmaker program scores≤7 corresponding to HLA Class I antibodies of levels 1 and 2,with CCI values＞4.5 × 109/L within 24 hours,can obtain effective clinical platelet transfusion conclusions.Conclusion:When selecting HLA Class I compatible donors for IPTR patients,the grading avoids HLA Class I antibodies corresponding to donor antigens,and the donor selection strategy with the minimum scores of HLAMatchmaker program is comprehensively selected.The negative result confirmed by platelet cross-matching experiments has certain practical application value for improving platelet count in IPTR patients.