Effect of sublingual immunotherapy on platelet activity in children with allergic rhinitis / Efeito da imunoterapia sublingual sobre a atividade plaquetária em crianças com rinite alérgica

Abstract Introduction: The role of platelet activation in allergic inflammation is receiving increasing attention. Sublingual immunotherapy for allergic rhinitis can modify the immunological process to an allergen, rather than simply treating symptoms. Objective: The aim of this study was to explore the role of platelet activation during sublingual immunotherapy in children with allergic rhinitis. Methods: Forty-two House Dust Mite - sensitized children with allergic rhinitis were enrolled and received House Dust Mite allergen extract for sublingual immunotherapy or placebo. Serum of different time points during treatment was collected and used for detection of Platelet Factor-4 and Beta-Thromboglobulin concentration by Enzyme-Linked Immuno Sorbent Assay. Results: Our data showed decreased expression of Platelet Factor-4 and Beta-Thromboglobulin protein after one year's sublingual immunotherapy. In addition, the decrease of symptom scores and serum Platelet Factor-4 and Beta-Thromboglobulin protein concentrations was positively related. Conclusion: During sublingual immunotherapy, platelet activation was inhibited significantly. Our results might indicate that inhibition of platelet activation within the systemic circulation is an important mechanism during sublingual immunotherapy.

Resumo Introdução: O papel da ativação de plaquetas na inflamação alérgica recebeu atenção crescente. A imunoterapia sublingual para rinite alérgica pode modificar o processo imunológico a um alérgeno, em vez de tratar os sintomas simplesmente. Objetivo: Explorar o papel da ativação plaquetária durante a imunoterapia sublingual em crianças com rinite alérgica. Método: Quarenta e duas crianças com rinite alérgica sensibilizadas por ácaros de poeira domiciliar (APD) foram inscritas e receberam extrato de alérgeno de APD para imunoterapia sublingual ou placebo. O soro de diferentes pontos no tempo durante o tratamento foi recolhido e usado para a detecção de fator 4 plaquetário e concentração de beta-tromboglobulina por ensaio imunoenzimático. Resultados: Nossos dados mostraram diminuição da expressão de fator 4 plaquetário e proteína beta-tromboglobulina após imunoterapia sublingual de um ano. Além disso, a diminuição dos escores de sintomas e o fator 4 plaquetário sérico e concentrações de proteína beta-tromboglobulina foram relacionados de maneira positiva. Conclusão: Durante imunoterapia sublingual, a ativação plaquetária foi inibida significativamente. Os nossos resultados podem indicar que a inibição da ativação de plaquetas dentro da circulação sistêmica é um mecanismo importante durante imunoterapia sublingual.

Quantitative analysis of β thromboglobulin level in patients with coronary heart disease complicated dif-ferent complications / 心血管康复医学杂志

Objective:To compare serum level of β thromboglobulin in patients with coronary heart disease (CHD) complicated different complications.Methods:According to their complications,a total of 398 patients with unsta- ble angina pectoris (UAP)were divided into pure UAP group (UAP control group,n=82),hypertension group (n=89),diabetes mellitus (DM)group (n=133)and brain infarction group (n=94).Serum level of β thromboglobu- lin were measured and compared among four groups 6h after onset and before discharge.Incidence of myocardial in- farction within six months were followed up in four groups.Results:On 6h after onset,the serum level of β throm- boglobulin of brain infarction group,DM group,hypertension group,UAP control group was (61.13±3.32)ng/ml,(59.77±3.15)ng/ml,(52.12±3.27)ng/m, (48.55±3.14)ng/ml respectively,in which the level of brain infarction group was the highest,the difference between any two groups were significant (P0.05.Conclusion:β-thromboglobulin level during UAP onset is significant higher than that of remission period,and it rises most significantly in brain infarction group,and in this group the percentage of myocardial infarction occurred within six months is highest

Platelet Activation Markers (beta-thromboglobulin and platelet factor 4) and Clopidogrel Drug Response in Patients with Myocardiac Infarction

BACKGROUND: Dual antiplatelet therapy (aspirin and clopidogrel) is used to prevent adverse cardiac events in patients undergoing percutaneous coronary intervention (PCI). Some patients do not respond adequately to clopidogrel. Beta-thromboglobulin (beta-TG) and platelet factor 4 (PF-4) can act as markers to detect platelet activation. We investigated the relationship between clopidogrel response and the dynamics of beta-TG and PF4 concentrations. METHODS: This study included 36 myocardial infarction (MI) patients, who underwent PCI and was indicated for dual antiplatelet therapy. Platelet reactivity, using the VerifyNow P2Y12 assay, was measured on the 3rd day of PCI. At the time of admission, and on the 3rd and 10th day of PCI, the plasma beta-TG and PF4 concentrations were quantified. RESULTS: Ten patients (27.8%) were clopidogrel non-responders displaying >208 P2Y12 reaction units. At the time of admission, levels of beta-TG in patients were elevated than that in the healthy controls (P<0.001). A similar trend was observed on the 3rd and 10th day of PCI (P<0.001). The beta-TG levels on the 10th day were reduced than those at the time of admission and on the 3rd day of PCI. PF4 levels were not different between patients and controls, and were not significantly reduced after PCI. Higher beta-TG levels were observed in clopidogrel non-responders on the 10th day, but not significant. CONCLUSIONS: Clopidogrel therapy in MI reduce beta-TG concentration, but the beta-TG and PF4 levels before and after therapy are not associated with the response to clopidogrel. Platelet-derived markers may not be suitable for distinguishing clopidogrel non-responders.

The effects of plasma low high-density lipoprotein cholesterol on platelet cytosolic free calcium and release reaction / 中国实用内科杂志

Objective To discuss pathogenic effects of low high-density lipoprotein cholesterol(HDL-C)on atherosclerosis and thromboembolism,the influences of HDL-C on platelet cytosolic free calcium concentration([Ca2+]i),platelet release reaction products beta-thromboglobulin(?-TG)and platelet factor 4(PF4)were observed in dyslipoproteinemia patients with low HDL-C.Methods i,?-TG and PF4 were measured by fluorescent probe Fura 2-AM and ELISA skills respectively,in 42 patients with low HDLC(LHDL-C)and 25 healthy controls(CONT).Results Compared with those in CONT group,the platelet[Ca2+]i,?-TG and PF4 were all higher in LHDL-C group(all P

Platelet Activation and Storage lesions in Apheresis Platelet Concentrates / 대한수혈학회지

BACKGROUND: Three cell separators are being used and they collect platelets with different centrifuge speed and duration. Because centrifugation may cause platelet activation, the differences of centrifuge speed and duration are important in controlling the quality of apheresis platelet products. We compared many parameters of activation of platelets collected by Spectra (Cobe BCT, Lakewood, CO, USA), CS3000plus (Baxter Healthcare, Fenwal Division, Round Lake, IL, USA) and Mobile Collection SystemTM (MCS, Haemonetics co., Braintree, MA, USA). METHODS: Platelets were collected from ninety-five normal donors with Spectra (n=39), CS3000plus (n=19) and MCS (n=37). We underwent the procedure according to the automatic program set. We measured platelet yield and assayed pH, hypotonic shock respose (HSR), CD62 (p-selectin, GMP140) expression and beta-thromboglobulin in each stored unit on day 0 and day 3 for evaluation of the storage lesions. RESULTS: Platelet yield per product was 3.7 +/- 1.2 x 1011, mean final product volume was 316 +/- 69 mL and mean procession time was 100 +/- 19 minutes. Mean collection efficiency was 42.5 +/- 8.3%. The cell separator volume of product collected by CS3000plus was the smallest while platelet concentration and total yield were the highest in the product collected by Spectra. The pH of the products were 7.1 +/- 0.1 on day 0 and 6.7 +/- 0.4 on day 3. Hypotonic shock response was 69 +/- 13 % on day 0 and 28 +/- 17 % on day 3. P-selectin expression was 19 +/- 9 % (4.2 +/- 1.9 relative fluorescence intensity, RFI) on day 0 and 60 +/- 22 % (17.9 +/- 14.2) on day 3. beta-thromboglobulin was 28.5 +/- 7.0 IU/107 platelets on day 0 and 31.3 +/- 7.2 IU/107 platelts on day 3. The comparison of the three cell separators showed that on day 0 platelet product of MCS has lower pH and higher beta-thromboglobulin release than others (p<0.05). And on day 3 platelet product of MDS has better hypotonic shock response than others (p<0.05). Other parameters revealed no differences among three cell separators. The expression of p-selectin was shown to correlate highly with pH reduction (r=0.72), but not with the release of beta-TG (r=0.24). CONCLUSIONS: Most parameters showed no differences among three cell separators, but apheresis platelet concentrates processed by MCS showed lower pH on day 0 and higher beta-thromboglobulin concentration on day 0 and day 3 than apheresis platelet concentrates processed by Spectra or CS3000plus and hypotonic shock response on day 3 was the lowest in CS3000plus. So platelet activation produced during apheresis processing was lowest in apheresis platelet concentrates with Spectra.