Painful Diabetic Neuropathy Is Associated with Compromised Microglial IGF-1 Signaling Which Can Be Rescued by Green Tea Polyphenol EGCG in Mice.

Background: Painful diabetic neuropathy (PDN) is a frequent and troublesome complication of diabetes, with little effective treatment. PDN is characterized by specific spinal microglia-mediated neuroinflammation. Insulin-like growth factor 1 (IGF-1) primarily derives from microglia in the brain and serves a vital role in averting the microglial transition into the proinflammatory M1 phenotype. Given that epigallocatechin-3-gallate (EGCG) is a potent anti-inflammatory agent that can regulate IGF-1 signaling, we speculated that EGCG administration might reduce spinal microglia-related neuroinflammation and combat the development of PDN through IGF-1/IGF1R signaling. Methods: Type 1 diabetes mellitus (T1DM) was established by a single intraperitoneal (i.p.) injection of streptozotocin (STZ) in mice. The protein expression level of IGF-1, its receptor IGF1R, interleukin 1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) was determined by Western blot or immunofluorescence. Results: The spinal IGF-1 expression markedly decreased along with the presence of pain-like behaviors, the spinal genesis of neuroinflammation (increased IL-1ß, TNF-α, and Iba-1+ microglia), and the intensified M1 microglia polarization (increased iNOS+Iba-1+ microglia) in diabetic mice. IGF-1 could colocalize with neurons, astrocytes, and microglia, but only microglial IGF-1 was repressed in T1DM mice. Furthermore, we found that i.t. administration of mouse recombinant IGF-1 (rIGF-1) as well as i.t. or i.p. treatment with EGCG alleviated the diabetes-induced pain-like behaviors, reduced neuroinflammation (suppressed IL-1ß, TNF-α, and Iba-1+ microglia), prevented the M1 microglia polarization (less iNOS+Iba-1+ microglia), and restored the microglial IGF-1 expression. Conclusions: Our data highlighted the importance of maintaining spinal IGF-1 signaling in treating microglia-related neuroinflammation in PDN. This study also provides novel insights into the neuroprotective mechanisms of EGCG against neuropathic pain and neuroinflammation through IGF-1 signaling, indicating that this agent may be a promising treatment for PDN in the clinical setting.

Chemotherapy-induced peripheral neuropathy is promoted by enhanced spinal insulin-like growth factor-1 levels via astrocyte-dependent mechanisms.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common and intractable complication in chemotherapy-receiving patients. Insulin-like growth factor-1 (IGF-1) is a popular neurotrophin with various functions, such as maintaining neuronal survival and synaptic functioning in the central nervous system. Therefore, we hypothesized that the IGF-1 signaling pathway could be a candidate target for treating CIPN. METHODS: We established the CIPN model by injecting mice intraperitoneally with oxaliplatin and assessed IGF-1 protein expression, its receptor IGF1R, phospho-IGF1R (p-IGF1R), interleukin-17A (IL-17A), tumor necrosis factor-α (TNF-α), and calcitonin gene-related peptide (CGRP) in the lumbar spinal cord with Western blot and immunofluorescence. To examine the effect of IGF-1 signaling on CIPN, we injected mice intrathecally or intraperitoneally with mouse recombinant IGF-1 (rIGF-1). RESULTS: IGF-1 protein expression decreased significantly in the spinal cord on D3 and D10 (the 3rd and 10th days after beginning oxaliplatin chemotherapy) and was co-localized with astrocytes primarily in the lumbar spinal cord, whereas IGF1R was predominantly expressed on neurons. Both intrathecally- and intraperitoneally-administered rIGF-1 relieved the chemotherapy-induced pain-like behavior and reduced IL-17A, TNF-α, and CGRP protein expressions in the spinal cord. CONCLUSION: Our results indicate a vital role for IGF-1 signaling in CIPN. Targeting IGF-1 signaling could be a potent therapeutic strategy for treating CIPN in clinical settings.

Abnormal Insulin-like Growth Factor 1 Signaling Regulates Neuropathic Pain by Mediating the Mechanistic Target of Rapamycin-Related Autophagy and Neuroinflammation in Mice.

Neuropathic pain is a chronic condition with little specific treatment. Insulin-like growth factor 1 (IGF1), interacting with its receptor, IGF1R, serves a vital role in neuronal and brain functions such as autophagy and neuroinflammation. Yet, the function of spinal IGF1/IGF1R in neuropathic pain is unclear. Here, we examined whether and how spinal IGF1 signaling affects pain-like behaviors in mice with chronic constriction injury (CCI) of the sciatic nerve. To corroborate the role of IGF1, we injected intrathecally IGF1R inhibitor (nvp-aew541) or anti-IGF1 neutralizing antibodies. We found that IGF1 (derived from astrocytes) in the lumbar cord increased along with the neuropathic pain induced by CCI. IGF1R was predominantly expressed on neurons. IGF1R antagonism or IGF1 neutralization attenuated pain behaviors induced by CCI, relieved mTOR-related suppression of autophagy, and mitigated neuroinflammation in the spinal cord. These findings reveal that the abnormal IGF1/IGF1R signaling contributes to neuropathic pain by exacerbating autophagy dysfunction and neuroinflammation.

Determination of the chemical components and phospholipids of velvet antler using UPLC/QTOF-MS coupled with UNIFI software.

Velvet antler, which exhibits immune and growth enhancing effects, is commonly used in a variety of Asian health care products, but its complex components remain unknown. The current study analyzed extracts using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry in the MSE mode. Automated detection and data filtering were performed using UNIFI software and peaks were compared with a proprietary scientific library (Traditional Medicine Library; TML). The results obtained using different data processing parameters (including 3D peak detection, target by mass and fragment identification) were evaluated against 87 compounds comprising 1 lignan, 30 terpenoids (including 20 triterpenes), 39 steroids, 8 alkaloids, 4 organic acids and 5 esters in the TML. Using a screening method with a mass accuracy cutoff of ±2 mDa, a retention time cutoff of ±0.2 min, a minimum response threshold of 1,000 counts and an average of 10 false detects per sample analysis, 16 phospholipids were identified in the extracts of velvet antler, three of which were quantified. The results demonstrated that there was 1.07±0.02 µg/g of 1-myristoyl-sn-glycero-3-phosphocholine, 7.05±0.52 ng/g of 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 18.81±0.55 ng/g of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine in velvet antler. The current study successfully identified certain components of velvet antler. Furthermore, the results may provide an experimental basis for further pharmacological and clinical study.

Measurement of Giardia lamblia adhesion force using an integrated microfluidic assay.

The mechanisms how Giardias attach to the intestinal epithelium remain unclear. None of the methods currently being used to measure the attachment force could provide a continuous nutrition supply and a micro-aerobic atmosphere to the Giardia. Besides, they are all labor-intensive. In the present research, a microfluidic method based on electric circuit analogy was developed. The input fluid flowed through the inlet channel with different lengths and was distributed in four assay chambers. Shear force gradients were generated in chambers, too. This allowed an easy control of fluids and the shear forces. Most importantly, the shear stress large enough to detach Giardia could be generated in laminar flow regime. Moreover, analysis could be accomplished in one single test. By applying inlet flow rates of 30, 60, and 120 µL ml-1, shear force gradients ranging from 19.47 to 60.50 Pa were generated. The adhesion forces of trophozoites were analyzed and the EC50 of the force that caused 50% trophozoites detachment was calculated as 36.60 Pa. This paper presents a novel method for measurement of Giardia adhesion force. Graphical Abstract Measurement of Giardia adhesion force. Various of flow rates were applied to generate different shear forces and Giardia trophozoites remaining attached were counted (a-c). The percentages of attachment vs shear stress were plotted and the EC50 of adhesion force was calculated (d).

Giardia duodenalis GlSir2.2, homolog of SIRT1, is a nuclear-located and NAD(+)-dependent deacethylase.

Sir2 family proteins are highly conserved and catalyze Nicotinamide Adenine Dinucleotide (NAD(+))-dependent protein deacetylation reaction that regulates multiple cellular processes. Little is known about Sir2 family proteins in Giardia. In this research, Sir2 homologs of Giardia were Phylogenetically analyzed. GL50803_10707 (GlSIR2.2) showed strong homology to SIRT1 and was the only parasite SIRT1 homolog being reported to date. Recombinant GlSIR2.2 (rGlSIR2.2) was expressed and purified. The renaturied recombinant protein showed a typical NAD-dependent protein deacetylase activity that could be inhibited by nicotinamide, with IC50 of 4.47 mM rGlSIR2.2 displayed deacetylase activity under varied NAD(+), with Km, kcat and kcat/Km values of 31.71 µM, 1.4 × 10(-3) s(-1), and 4.42 × 10(-5) µM(-1) s(-1). Similarly, the steady-state kinetic parameters with varied ZMAL, yielded Km, kcat and kcat/Km values of 96.89 µM, 4.7 × 10(-3) s(-1), and 4.85 × 10(-5) µM(-1) s(-1). Anti-rGlSIR2.2 serum was used to probe subcellular localization of GlSIR2.2 and strong staining was found predominantly in the nucleus. So we demonstrated that GlSIR2.2 was a SIRT1-like, nuclear-located, NAD(+)-dependent deacetylase. This is the first report of deacetylase activity of Sir2 family protein in Giardia.

Expression and clinical significance of nestin in astrocytic tumors.

PURPOSE: This study aimed to investigate the expression and clinical significance of nestin in human astrocytic tumors. METHODS: Indirect immunofluorescent staining and flow cytometry were used to quantitatively detect the nestin content in 35 specimens, including 3 normal brain tissues, 29 astrocytic tumor (AT) tissues, and 3 peritumoral tissues. RESULTS: In normal brain tissues, nestin expression was extremely low. Nestin expression was significantly positively correlated with the histological grade of astrocytic tumors (p<0.05, rs=0.83). Nestin content in the peritumoral tissues was between the levels of nestin in tumor tissue and in normal brain tissue (p<0.01). Nestin expression was unrelated to the patient's gender, age, tumor location, size, etc. (p>0.05). CONCLUSION: The application of flow cytometry in the determination of nestin content could improve the accuracy of early cancer diagnosis. This method would be helpful for developing a reference range that is closely related to the pathological grading of ATs through routine assessments of nestin in many patients. Additionally, through examining nestin levels in peritumoral tissues, the invasiveness of ATs can be clarified.

MicroRNA-29a: A potential biomarker in the development of intracranial aneurysm.

AIM: To identify serum microRNA-29a (miR-29a) level in patients with intracranial aneurysm and its role in the development of intracranial aneurysm (IA). METHODS: Case group included 165 IA patients hospitalized in the department of neurosurgery between January 2010 and January 2012 while control group enrolled 220 healthy volunteers. Morning fasting blood samples were collected from peripheral vein. RT-PCR was used for miR-29a detection. Receiver Operating Characteristic (ROC) curve was drawn. Survival curves were drawn for survival analysis with Kaplan-Meier method and Long-rank test was conducted. MiR-29a expression Glasgow Prognosis Score (GOS) was used for prognosis scaling. Multivariate Cox proportional hazards regression analysis was performed for prognosis analysis. Results Cases had significantly higher miR-29a expressions than controls (P<0.05). ROC curve analysis indicated that miR-29a expression in IA had high effectiveness in IA diagnosis. Close associations were identified between miR-29a expression and rupture, Hunt-Hess level and surgical timing (all P<0.05). GOS strongly associated with history of hypertension, aneurysm location, rupture, Hunt-Hess level and miR-29a expression. Patients with low miR-29a expression had longer disease-free survival (DFS) and overall survival (OS) than those with high miR-29a expression (both P<0.05). MiR-29a expression, tumor aneurysm, rupture and Hunt-Hess were risk factors to the prognosis of IA (all P<0.05). CONCLUSION: MiR-29a may be closely related to IA development and therefore could be a useful predicator of IA prognosis, providing a new target for IA therapy.

Primary intratesticular rhabdomyosarcoma: A case report and literature review.

Rhabdomyosarcoma (RMS) that primarily occurs in the testes is particularly rare, with only retrospective studies and sporadic cases reported in the literature. The present study describes the case of a large, primary intratesticular RMS (ITRMS) that was treated with a radical inguinal orchiectomy (RIO) and a regimen of chemotherapy. The study also presents a review of the literature regarding primary ITRMSs, aiming to elucidate the clinical characteristics and optimal treatment of the disease. A 14-year-old male presented with a 1-year history of a slow-growing, painless, left scrotal mass. Magnetic resonance imaging identified a mass in the left scrotum with mixed signal intensity; no abnormal signals were identified in the right testicle and retroperitoneal lymph node. An X-ray of the chest demonstrated no evidence of metastasis. Subsequent to this, a left RIO was performed. Histopathological and immunohistochemical examination confirmed the final diagnosis of embryonal ITRMS. At 21 days post-surgery, an 18F-fluorodeoxyglucose-positron emission tomography-computed tomography (FDG-PET-CT) scan identified widespread metastatic lesions in the lungs, local lymph nodes and bones, presenting as increased glucose metabolism nodules. Subsequently, the patient received six sequential cycles of adjunct chemotherapy. The patient is alive with disease in October 2015. The case described is noteworthy as it is an example of ITRMS, in which the patient received successful treatment. However, multidisciplinary treatment may further improve the outcome of the disease.

An on-chip pollutant toxicity determination based on marine microalgal swimming inhibition.

We report the use of microalgal swimming behavior as a sensor signal integrated into microfluidics for a rapid and high-throughput determination of pollutant toxicity. There are two types of chip. A poly(dimethylsiloxane) (PDMS) 12-well chip, used for optimization of experimental conditions (i.e. light level, temperature, initial cellular density and exposure time), can perform twelve parallel tests simultaneously. In a concentration gradient generator (CGG) chip, a CGG connected with diffusible chambers enables a large number of dose-response bioassays to be performed in a simple way. Microalgal swimming was set as a microfluidic bioassay signal and was evaluated as swimming manner, motile percentage (%MOT), curvilinear velocity (VCL), average path velocity (VAP) and straight line velocity (VSL). Under optimized physical conditions, the toxicities of Cu, Pb, phenol and nonylphenol (NP) towards four mobile marine microalgae, Platymonas subcordiformis, Platymonas helgolandica var. tsingtaoensis, Isochrysis galbana and Isochrysis zhanjiangensis sp. nov, were investigated. In all cases, a toxic response (i.e. a dose-related inhibition of swimming) was detected, and a time of only 2 h was needed to predict EC50 values. The 2h-EC50s showed that I. galbana was the most tolerant and that P. subcordiformis was one of the most sensitive. Based on the relative motile percentage data, the EC50 values for Cu of I. galbana and P. subcordiformis were 6.04 and 1.67 µM, respectively, while for Pb the EC50 values were 15.30 and 3.87 µM, for phenol the EC50 values were 8.69 and 6.08 mM, and for NP the EC50 values were 29.65 and 14.47 µM, respectively. Taking into account all the swimming inhibition parameters, MOT provided more sensitive EC results. The sensitivity differences between the velocity parameters (VCL, VAP and VSL) were ascribed to differences in swimming manner of the different classes of microalgae.

MicroRNA-184 promotes proliferation ability of glioma cells by regulating FOXO3.

OBJECTIVES: To investigate the effect of microRNA (miR-184) on regulating the genesis, development and proliferation of glioma cells. METHODS: Lipidosome was used to transfect miR-184 mimic and inhibitor to glioma cell line, and the cell proliferation ability changes were determined by MTT and plate cloning experiment after the transfection. WB test was used to measure the levels of cyclinD1, p27 and FOXO3. Meanwhile, QPCR was used to detect miR-184 expression in glioma cell line, glioma tissues and adjacent tissues. Luciferase experiment was used to test 3'UTR gene targeting regulation of miR-184 and FOXO3. RESULTS: QPCR results showed a significant lower miR-184 expression level in glioma cell line and glioma tissues than that in juxtacancerous tissue. MTT and plate cloning experiments have shown that after over-expressing of miR-184, the cell proliferation capacity of glioma U87 and T98G was significantly increased, which was significantly inhibited after the inhibition of miR-184. WB results showed a lower expression level of p27 in U87 and T98G cells, and a higher expression level of cyclinD1 after over-expressing of miR-184 was observed. However, a lower expression level of cyclinD1 and a higher expression level of p27 after the inhibition of miR-184. The luciferase activity was inhibited after the over-expressing of miR-184. CONCLUSIONS: MiR-184 can affect the proliferation abilities of glioma cells and regulate the cell cycle related protein. It plays an important role in the occurrence and development of gliomas.

Marine phytoplankton motility sensor integrated into a microfluidic chip for high-throughput pollutant toxicity assessment.

A microfluidic chip was designed to assess the toxicity of pollutants in a high-throughput way by using marine phytoplankton motility as a sensor signal. In this chip, multiple gradient generators (CGGs) with diffusible chambers enable large scale of dose-response bioassays to be performed in a simple way. Two mobile marine phytoplankton cells were confined on-chip and stimulated by 8 concentrations (generated by CGG) of Hg, Pb, Cu and phenol singly, as well as Cu and phenol jointly. CASA system was used to characterize motility by motile percentage (%MOT), curvilinear velocity (VCL), average path velocity (VAP) and straight line velocity (VSL). In all cases, dose-dependent inhibitions of motility were observed. In the present system, only 2h was needed to predict EC50. Thus, the developed microfluidic chip device was proved to be useful as a rapid/simple and high-throughput test method in marine pollution toxicity assessment.

Paper-based three-dimensional microfluidic device for monitoring of heavy metals with a camera cell phone.

A 3D paper-based microfluidic device has been developed for colorimetric determination of selected heavy metals in water samples by stacking layers of wax patterned paper and double-sided adhesive tape. It has the capability of wicking fluids and distributing microliter volumes of samples from single inlet into affrays of detection zones without external pumps, thus a range of metal assays can be simply and inexpensively performed. We demonstrate a prototype of four sample inlets for up to four heavy metal assays each, with detection limits as follows: Cu (II) = 0.29 ppm, Ni(II) = 0.33 ppm, Cd (II) = 0.19 ppm, and Cr (VI) = 0.35 ppm, which provided quantitative data that were in agreement with values gained from atomic absorption. It has the ability to identify these four metals in mixtures and is immune to interferences from either nontoxic metal ions such as Na(I) and K(I) or components found in reservoir or beach water. With the incorporation of a portable detector, a camera mobile phone, this 3D paper-based microfluidic device should be useful as a simple, rapid, and on-site screening approach of heavy metals in aquatic environments.

An integrated microfludic device for culturing and screening of Giardia lamblia.

In vitro culturing of trophozoites was important for research of Giardia lamblia (G. lamblia), especially in discovery of anti-Giardia agents. The current culture methods mainly suffer from lab-intension or the obstacle in standardizing the gas condition. Thus, it could benefit from a more streamlined and integrated approach. Microfluidics offers a way to accomplish this goal. Here we presented an integrated microfluidic device for culturing and screening of G. lamblia. The device consisted of a polydimethylsiloxane (PDMS) microchip with an aerobic culture system. In the microchip, the functionality of integrated concentration gradient generator (CGG) with micro-scale cell culture enables dose-response experiment to be performed in a simple and reagent-saving way. The diffusion-based culture chambers allowed growing G. lamblia at the in vivo like environment. It notable that the highly air permeable material of parallel chambers maintain uniform anaerobic environment in different chambers easily. Using this device, G. lamblia were successfully cultured and stressed on-chip. In all cases, a dose-related inhibitory response was detected. The application of this device for these purposes represents the first step in developing a completely integrated microfluidic platform for high-throughput screening and might be expanded to other assays based on in vitro culture of G. lamblia with further tests.

Association of ERCC1 rs3212986 & ERCC2 rs13181 polymorphisms with the risk of glioma.

OBJECTIVE: : Several previous studies have reported the role variant of ERCC1 rs3212986 and ERCC2 rs13181 polymorphisms in the risk of glioma, but the results of these studies are inconsistent. Therefore, we aimed to conduct a meta-analysis to investigate the role of ERCC1 rs3212986 and ERCC2 rs13181 on the risk of glioma. METHODS: A comprehensive research was conducted through the databases of Pubmed, EMBASE and the China National Knowledge Infrastructure (CNKI) platforms until June 1, 2014, including 14 eligible case-control studies. RESULTS: Our meta-analysis found that ERCC1 rs3212986 AA genotype was significantly associated with increased risk of glioma compared with CC genotype, and the pooled OR (95%CI) was 1.29(1.07-1.55). By subgroup analysis, ERCC1 rs3212986 AA genotype was found to be significantly correlated with increased glioma risk in Chinese population (OR=1.37, 95%CI=1.07, 1.55), Similarly, we found that ERCC2 rs13181 GT and TT genotypes were significantly associated with increased risk of glioma in Chinese population, with ORs(95%CI) of 1.47(1.17-1.85) and 1.50(1.02-2.22). But ERCC1 rs3212986 and ERCC2 rs13181 polymorphisms had no significant association with glioma risk in Caucasian populations. By begg's funnel plot, we found that no publication bias was existed in this meta-analysis. CONCLUSION: Our meta-analysis suggested that ERCC1 rs3212986 and ERCC2 rs13181 polymorphism play an important risk factor for brain tumor development in Chinese population, but no association in Caucasian populations.

[Effect of control interventions for intestinal nematodiasis in areas with low prevalence in Changzhou City].

OBJECTIVE: To evaluate the effect of control interventions for intestinal nematodiasis in areas with low prevalence, so as to explorethe effective measures for the control of intestinal nematode infections in Changzhou City, Jiangsu Province, China. METHODS: The residents in Wujin, Jintan, Tianning districts were selected as monitor subjects and the infections of intestinal nematodes were investigated with Kato-Katz technique or the transparent tape anal swab method. The results were analyzed statistically and the cost-effectiveness was also analyzed. RESULTS: A total of 26 966 people were investigated and the total infection rate of intestinal nematodes was 0.37% (99/26 966). The infection rates of the local residents and floating population were 0.31% (63/20 267) and 0.55% (37/6 699), respectively, and the former was lower the latter (P < 0.01); the infection rates of urban residents and rural residents were 0.29% (44/15 328) and 0.47% (55/11 638),respectively, and the former was lower than the latter (P < 0.05). The 3 jurisdictions used different interventions, and the costs of 1% infection rate drop were 15.9 yuan/thousand people in Wujin District, 1.9 yuan/thousand people in Jintan District, and 1.7 yuan/thousand people in Tianning District. The cost in Jintan was lower than that in Wujin, but the infection rate drop in Jintan was more than that in Wujin. CONCLUSION: The floating population as well as the rural residents is still the focus and difficulty of the intestinal nematodiasis control. The deworming and health education are the main interventions in the key population.

Single molecular functionalized gold nanoparticles for hydrogen-bonding recognition and colorimetric detection of dopamine with high sensitivity and selectivity.

In this work, we developed a low-cost, facile, sensitive, and selective colorimetric method for the quantitative determination of dopamine, based on 4-amino-3-hydrazino-5-mercapto-1,2,4-triazol (AHMT) functionalized gold nanoparticles (AHMP-AuNPs) as a model probe. Dopamine could induce the aggregation of the AHMT-AuNPs through hydrogen-bonding interactions, which caused the colloidal solution changed from red to blue. And the color change was in situ monitored for the quantitative determination of dopamine in human serum and urine samples. The developed approach is simple, without using complex financial instruments and adding other metal salts or ions for improving sensitivity.

[Construction of rapid tagging vector of genes in Giardia lamblia].

OBJECTIVE: To construct a recombinant vector for rapid gene tagging in Giardia lamblia. METHODS: To obtain the recombinant vector pGL gdh-Neo with the Neo selection marker, the Neo gene was put under the control of gdh promoter by overlap PCR and inserted into pGEM-5zf. A DNA fragment containing multiple cloning sites (MCS) followed by triple hemagglutinin(3HA) coding sequences was synthesized and cloned into the pGL gdh-Neo to construct a recombinant vector pGL MCS-3HA-gdh-Neo. Giardia H2A gene was selected as a tagging gene to validate the effectivity of the recombinant vector pGL MCS-3HA-gdh-Neo. The histone H2A coding sequence was amplified by PCR, digested with EcoR I and Spe I, and inserted into MCS of pGL MCS-3HA-gdh-Neo. The resulting plasmid was then linearized and transfected into Giardia trophozoites. The H2A recombinant strain selected by G418 was analyzed by PCR,Western blotting and immunofluorescence. RESULTS: A rapid tagging recombinant vector with multiple cloning sites and triple hemagglutinin (3HA) was constructed with a length of 4 260 bp. The H2A recombinant vector was transfected into Giardia trophozoites and integrate into the Giardia genome at the correct locus. The HA-tagged H2A protein was expressed with a molecular weight (Mr) of 16 900. CONCLUSION: A rapid tagging recombinant vector of genes in Giardia lamblia, pGL MCS-3HA-gdh-Neo, has been constructed.