Dynamic Changes and Differences of B-cell Responses between Severe Dengue Disease and Mild Dengue Fever / 中山大学学报(医学科学版)

@#【Objective】 To find out the possible marker for early warning or therapeutic target of severe dengue disease ，we studied B cell responses during natural dengue virus（DENV）infection and their association with disease severity.【Methods】Sixty-two cases and their blood samples were collected from the patients hospitalized during September to December in 2014 and three groups were designated as mild dengue（DF，n=33），severe dengue（SD，n=29）and control group（Control ，n=6）. Multicolor flow cytometrywas used to analyze the dynamic changes of B cells and plasmablasts in the peripheral blood of patients during the acute phase and the critical phase. The plasmablasts in a succession of samplesfrom the same infected patients （including 3 mild and 3 severe cases） were further analyzed. We also observed the changes of B cells and their subsets ，including naive B cells ，memory B cells and plasmablasts，during primary and secondary infections. 【Results】 The expansion of B cells in the severe group was significantly higher than that in the mild group（P=0.013），especially on day 5 and day 6 after the symptom onset（P = 0.017 and 0.002，respectively）. Compared with those in the control group，the plasmablasts in the mild and severe groups showed significant proliferation（P=0.011 and 0.032，respectively），but no statistical difference was observed between these two groups. The analysis of the serial blood samples showed that the plasmablasts，in mild cases，peaked on day 7 and 8 and returned to baseline on day 10，whereas in the severe group，peaked on day 7 to 9，and still existed at a certain rate after day 10. In mild dengue group，more proliferative B cells，less naive B cells and memory B cells were found in secondary infection than in primary infection（P = 0.028，0.010 and 0.037，respectively），but plasmablasts revealed no difference. In severe dengue group， only naïve B cells significantly decreased in secondary infection （P = 0.018）. 【Conclusion】 B cell responses between mild and severe dengue after DENV- 1 infection present different trends. The significant proliferation of B cells in the early stage of the disease and the persistent existence of plasmablasts may be related to the severity of the dengue disease.

Clinical characteristics of the patients with dengue fever seen from 2002 to 2006 in Guangzhou / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the clinical characteristics of the patients with dengue fever (DF) seen from 2002 to 2006 in Guangzhou in order to prevent and treat dengue fever better.</p><p><b>METHODS</b>Clinical data from 1342 inpatients with DF seen from 2002 to 2006 were retrospectively analyzed. The dengue virus was isolated by C6/36 cell culture and genotyped by reverse transcriptase-polymerase chain reaction and gene sequence analysis.</p><p><b>RESULTS</b>The average age of the patients was 34.4 years, without sex difference in distribution. Most of the patients had obvious toxemic symptoms including fever (100 percent), headache (85.9 percent), myalgia (64.5 percent), bone soreness (46.6 percent) and skin rash (65.9 percent). Leukopenia, thrombocytopenia, elevated alanine aminotransferase, elevated aspartate aminotransferase and hypokalemia were found in 66.0 percent, 61.3 percent, 69.0 percent , 85.7 percent and 28.4 percent of patients, respectively. DF-IgM could be detected in 90 percent of patients. The virus was identified as dengue virus type-I.</p><p><b>CONCLUSIONS</b>The epidemic of DF was caused by dengue virus- I from 2002 to 2006 in Guangzhou. Most of the patients had classic DF clinical manifestation with high percentage of hepatic injury. Few patients progressed to dengue hemorrhagic fever.</p>

Analysis on clinical and epidemiological characteristics of 1032 patients with Dengue fever in Guangzhou / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the clinical and epidemiological characteristics of Dengue fever (DF) during the Dengue-1 epidemic in Guangzhou.</p><p><b>METHODS</b>Clinical and epidemiological data of 1032 patients with DF from May 2002 to November 2003 were retrospectively analyzed. Dengue virus were isolated by cell culture and typed by reverse transcriptase polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Age of the patients ranged from 55 days to 91 years old (average 34.7 +/- 13.2 years) with sex ratio 1.03:1. Incubation period ranged from 2 to 12 days with mean periods of 5.3 +/- 2.4 days. Most (45.0%) cases appeared in September and the epidemic last from July to November. Dengue outbreak had involved 675 cases in 26 common places. The common manifestations were seen as fever (100%), headache (90.9%), myalgia (68.4%), bone soreness (48.8%), fatigue (79.3%), skin rash (60.1%), positive tourniquet test (45.3%), leukopenia (63.3%) and thrombocytopenia (60.8%), respectively. Dengue virus was isolated from serum of 19 out of 54 patients' and identified as Dengue virus type 1. DNA sequence analyzes on rates of nucleotide homology were 97%, 97% and 98% compared with those of Dengue virus type 1 strain of DF outbreak in Cambodia, in 1997 and 1999 in China.</p><p><b>CONCLUSION</b>The epidemic of DF in Guangzhou in 2002/2003 was caused by Dengue virus type-1 with most patients showing classic type of the disease. Date suggested that change can happen from non-endemic to hypoendemic regions in Guangdong province.</p>