Studies of the mechanism of HIV entry and transmission have identified multiple new targets for drug development. A range of inhibitors have demonstrated potent antiretroviral activity by interfering with CD4-gp120 interaction, coreceptor binding or viral-cell fusion in preclinical and clinical studies. One of these agents, fusion inhibitor enfuvirtide, is already in clinical use. Here we review the progress in the development of specific entry inhibitors as novel therapeutics. The potential of entry inhibitors as topical microbicides to block HIV transmission is also discussed.

Objective:To compare the immune responses to simply mixed and fused recombinant DNA vaccines of herpes simplex virus type 2 glycoprotein D (HSV-2 gD) and molecular adjuvant CCL19 in mice and to evaluate the protective effects.Methods:Gene recombination technology was used to construct recombinant DNA vaccines expressing HSV-2 gD and CCL19 alone or fused together. After verification by sequencing, Western blot and ELISA, BALB/c mice were immunized twice by intramuscular injection. Serum samples and vaginal lavage fluids were collected regularly after immunization. Splenocytes, mesenteric lymph node cells and rectal tissues were collected after immunization. Differences in humoral and cellular immune responses to the two forms of vaccines and their protective effects in mice were analyzed using end-point ELISA, in vitro neutralization assay, immunohistochemical staining, chemotaxis assay, vaginal virus challenge, fluorescence quantitative PCR, weighing and disease severity assessment. Results:The fused recombinant pgD-IZ-CCL19 plasmid could express gD protein and CCL19 protein in vitro, but the level of expressed CCL19 protein by pCCL19-IZ-gD plasmid was less than that by pgD-IZ-CCL19. The mice immunized with pgD-IZ-CCL19 showed higher levels of IgG in sera and IgA in vaginal lavage fluids ( P<0.01) and stronger neutralization ability than the mice vaccinated with pgD+ pCCL19. Compared with other groups, more lymphocytes were recruited in the rectal mucosa, the spleen and mesenteric lymph nodes of mice immunized with pgD-IZ-CCL19. Weight loss or disease symptoms were not observed in the pgD-IZ-CCL19 group after virus challenge. In addition, the positive rate of HSV-2 in vaginal mucosa and the mortality rate in the pgD-IZ-CCL19 group were the lowest. However, pCCL19-IZ-gD turned out ineffective in preventing HSV-2 infection. Conclusions:The fused recombinant DNA vaccine pgD-IZ-CCL19 could induce stronger immune responses in mice and provide better protective effects, which was superior to the simply mixed DNA vaccine.

Objective:To study the protective effects of bicistronic DNA vaccines carrying herpes simplex virus type 2 glycoprotein D (HSV-2 gD) and adjuvant CCL28 sequences that were connected by internal ribosome entry site (IRES) sequence in mouse model.Methods:The recombinant DNA vaccines, pgD-IRES-CCL28 and pCCL28-IRES-gD, encoding HSV-2 gD and adjuvant CCL28 were constructed with IRES sequence. After verified by sequencing, they were intramuscularly injected twice into BALB/c mice. Serum samples and vaginal lavage fluids were collected regularly. Splenocytes, mesenteric lymph node cells and rectal mucosa tissues were separated and collected. The titers of antigen-specific antibodies in immunized mice were analyzed with end-point ELISA. In vitro neutralization assay was used to measure neutralizing antibody titers in serum and vaginal lavage fluid after vaccination and virus challenge. CCL28-responsive immune cells in splenocytes, mesenteric lymph node cells and rectal tissues were detected by chemotaxis experiment and immunohistochemical staining. The protective effects of the bicistronic DNA vaccines were evaluated by fluorescent quantitative PCR, weighing and disease severity assessment. Humoral and cellular immune responses induced by the bicistronic DNA vaccines and their efficacy in immunoprotection were analyzed by comparing with pgD+ pCCL28 group. Results:IgG titers in serum samples and IgA antibody titers in vaginal lavage fluids of mice immunized with pCCL28-IRES-gD were similar to those in pgD+ pCCL28 group. The neutralizing ability of antibodies, the number of rectal mucosal IgA+ plasma cells and CCL28-responsive immune cells in mucosal tissues were increased in pCCL28-IRES-gD group. Serum neutralizing antibodies were not produced immediately in the mice challenged with HSV-2, but no weight loss, disease symptoms or death was observed. However, pgD+ pcDNA3.1 and pgD-IRES-CCL28 were ineffective against HSV-2 infection in mice.Conclusions:The recombinant bicistronic DNA vaccine of pCCL28-IRES-gD could induce stronger mucosal immune response in mice and provide better protective effects.

Objective: To observe the effects of minimally invasive tangential excision in treating deep partial-thickness burn wounds on trunk and limbs in pediatric patients in the early stage post burn. Methods: Clinical data of 40 children with deep partial-thickness burn wounds on trunk and limbs, admitted to our burn ward from January 2016 to June 2017, conforming to the study criteria, were retrospectively analyzed. They were divided into conventional treatment group (CT, n=19) and minimally invasive tangential excision group (MITE, n=21) according to the different treatments. The patients in group CT were treated with eschar-reserving therapy firstly. When tangential excision was performed, the roller knife was used, and no necrotic tissue left on the wound bed was considered the proper depth of excision. Razor-thickness skin grafting was performed to cover the wound when adipose tissue exposed markedly after tangential excision. Dressing change was performed within 48 h after the operation and repeated every 2 days. Unhealed wounds were covered by razor-thickness skin grafting. The patients in group MITE were treated with tangential excision in the early stage post burn. The tangential excision was operated with electric dermatome, and the thickness was set at 0.1 mm to excise the surface of eschar until the sporadic punctate hemorrhage on wound surface was observed and some necrotic tissue was left on the wound bed. Porcine acellular dermal matrix was applied after tangential excision. The first dressing change was often performed about 1 week after the operation. Razor-thickness skin grafting was performed to cover the unhealed wounds. The length of wound healing, high fever, antibiotic usage, and hospital stay, times of later operation, and hospitalization expenses of patients in the 2 groups were recorded. The excisional eschar and wound bed tissue of patients in group MITE were harvested for pathological observation. Data were processed with t test and Fisher′s exact probability test. Results: (1) There were no statistically significant differences in length of high fever and length of hospital stay and hospitalization expenses between patients in the 2 groups (t=-1.67, -1.93, 0.31, P>0.05). The lengths of wound healing [(24.8±2.5) d] and antibiotic usage [(4.4±0.7) d] of patients in group MITE were significantly shorter than those in group CT [(33.3±2.5) and (7.0±0.7) d, t=-2.44, -2.44, P<0.05], and times of later operation of patients in group MITE [(0.29±0.14) times] were significantly less than those in group CT [(0.79±0.21) times, t=-2.03, P<0.05]. (2) The thickness of the excisional eschar of patients in group MITE was about 150 μm. The eschar has epidermis and upper dermis. Some necrotic tissue was left on the wound bed. Conclusions The treatment for pediatric deep partial-thickness burn wounds on trunk and limbs with minimally invasive tangential excision using electric dermatome in the early stage post burn can accelerate wound healing, shorten length of antibiotic usage, and reduce times of later operations.

Objective:To explore the value of using metagenomic next-generation sequencing (mNGS) technology to detect pathogens in patients with burns and patients with acute or chronic wounds.Methods:A retrospective observational study was conducted. From March 2019 to June 2020, 11 patients with burns and patients with acute or chronic wounds (including 10 males and 1 female, aged 23 to 85 years) in the Fourth Medical Center of PLA General Hospital met the inclusion criteria and were recruited. A total of 23 specimens were collected, including 6 whole blood specimens, 1 skin tissue specimen, 1 drained pus specimen, and 15 wound secretion swab specimens. Each specimen was divided into two parts, which were subjected for pathogen detection using microbial culture method and mNGS method, respectively. The number and types of pathogens detected by the 2 methods and the relative abundance detected by the mNGS method were recorded, and the consistency of the two methods were compared. Data were statistically analyzed with paired Wilcoxon rank sum test.Results:With the microbial culture method, no pathogen was detected in 5 of the 23 specimens, while 35 pathogens were detected in the remaining 18 specimens, belonging to 9 species of bacteria and 2 species of fungi. Five specimens had one pathogen while 9 specimens had 2 pathogens and 4 specimens had 3 pathogens detected in each specimen. With the mNGS method, no pathogen was detected in one of the 23 specimens, while 75 pathogens were detected in the remaining 22 specimens, belonging to 28 species of bacteria, 3 species of fungi, and 3 species of viruses. Eight specimens had one pathogen, 5 specimens had 2 pathogens, 2 specimens had 3 pathogens, 3 specimens had 4 pathogens, 2 specimens had 6 pathogens, and 1 specimen had 7 pathogens, and 1 specimen had 20 pathogens detected in each specimen. The number of pathogens detected in each specimen by microbial culture method was 2 (1, 2) types, which was significantly less than 2 (1, 4) types by mNGS method ( Z=3.359, P<0.01). In 5 specimens, no bacteria were detected by microbial culture method but mNGS method detected bacteria in 2 specimens and virus in 2 different specimens. The mNGS method detected two or more types of bacteria in 13 specimens, the relative abundance of bacteria with the 1st relative abundance ranking ranged from 28.8% to 95.9% in each specimen. Of the 23 specimens detected by two detection methods, 7 specimens (30.4%) showed identical detection results, 5 specimens (21.7%) showed totally different detection results, and 11 specimens (47.8%) had partially consistent detection results. Conclusions:Compared with the traditional microbial culture method, the mNGS method has higher detection sensitivity and stronger capacity to detect pathogens, and can determine the relative abundance of pathogens in mixed infections. As a supplement to the culture method, the mNGS method is expected to play an important role in the diagnosis of infectious pathogens in burns and acute or chronic wounds.

Objective: To observe the clinical effects of stage-Ⅱ Meek skin grafting on adipose tissue after tangential excision in patients with extensive deep burns, and to explore the functional mechanism. Methods: The medical records of 26 extensively burned patients who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of the Fourth Medical Center of PLA General Hospital from May 2015 to December 2017 were retrospectively analyzed. According to the treatment methods, 14 patients were enrolled in stage-Ⅰ skin grafting group (10 males and 4 females, aged 27 to 75 years), and 12 patients were enrolled in stage-Ⅱ skin grafting group (10 males and 2 females, aged 31 to 76 years). Patients in the 2 groups all underwent debridement of tangential excision, and their healthy adipose tissue was preserved. Meek skin grafting was performed just after tangential excision in patients in stage-Ⅰ skin grafting group. In patients in stage-Ⅱ skin grafting group, porcine acellular dermal matrix (ADM) was applied to cover the wound after tangential excision, and 3 days later, it was removed and Meek skin grafting was performed. The times of complement skin grafting and the wound basic healing time of patients in the 2 groups were observed and recorded. In the stage-Ⅱ skin grafting group, the adipose tissue of patients were taken from the wound center immediately after tangential excision and immediately after the removal of porcine ADM, for the observation of structure of the fault surface of adipose tissue through hematoxylin and eosin staining and microvessel density (MVD) through immunohistochemical staining. Data were processed with independent sample t test and Fisher′s exact probability test. Results: (1) The times of complement skin grafting of patients in stage-Ⅱ skin grafting group was (1.83±0.17) times, which was obviously less than (3.36±0.63) times in stage-Ⅰ skin grafting group (t=2.19, P<0.05). The wound basic healing time of patients in stage-Ⅱ skin grafting group was (35.1±2.3) d, which was obviously shorter than (48.8±4.9) d in stage-Ⅰ skin grafting group (t=2.27, P<0.05). (2) Immediately after tangential excision, the intercellular substance was few between the adipose cells in adipose tissue of patients in stage-Ⅱ skin grafting group. Immediately after the removal of porcine ADM, there was regenerated granulation tissue in the intercellular space of adipose cells of adipose tissue of patients in stage-Ⅱ skin grafting group. Immediately after tangential excision, the MVD of adipose tissue of patients in stage-Ⅱ skin grafting group was 20.2±1.3 under per 400-time field, which was obviously less than 32.2±1.9 under per 400-time field immediately after the removal of porcine ADM (t=-5.38, P<0.01). Conclusions Meek skin grafting on the adipose tissue in stage-Ⅱ surgery after tangential excision could reduce the times of complement skin grafting and shorten wound healing time of patients with extensive deep burns. The mechanism may be related to the improvement of the recipient condition of adipose tissue.