Evaluating the role of interleukin-2 and interleukin-12 in pediatric patients with concurrent Mycoplasma pneumoniae and Epstein-Barr virus infections

BACKGROUND Mycoplasma pneumoniae(MP)frequently causes respiratory infections in children,whereas Epstein-Barr virus(EBV)typically presents subclinical manifestations in immunocompetent pediatric populations.The incidence of MP and EBV coinfections is often overlooked clinically,with the contributory role of EBV in pulmonary infections alongside MP remaining unclear.AIM To evaluate the serum concentrations of interleukin-2(IL-2)and interleukin-12(IL-12)in pediatric patients with MP pneumonia co-infected with EBV and assess their prognostic implications.METHODS We retrospectively analyzed clinical data from patients diagnosed with MP and EBV co-infection,isolated MP infection,and a control group of healthy children,spanning from January 1,2018 to December 31,2021.Serum IL-2 and IL-12 levels were quantified using enzyme-linked immunosorbent assay.Logistic regression was employed to identify factors influencing poor prognosis,while receiver operating characteristic(ROC)curves evaluated the prognostic utility of serum IL-2 and IL-12 levels in co-infected patients.RESULTS The co-infection group exhibited elevated serum IL-2 and C-reactive protein(CRP)levels compared to both the MP-only and control groups,with a reverse trend observed for IL-12(P<0.05).In the poor prognosis cohort,elevated CRP and IL-2 levels,alongside prolonged fever duration,contrasted with reduced IL-12 levels(P<0.05).Logistic regression identified elevated IL-2 as an independent risk factor and high IL-12 as a protective factor for adverse outcomes(P<0.05).ROC analysis indicated that the area under the curves for IL-2,IL-12,and their combination in predicting poor prognosis were 0.815,0.895,and 0.915,respectively.CONCLUSION Elevated serum IL-2 and diminished IL-12 levels in pediatric patients with MP and EBV co-infection correlate with poorer prognosis,with combined IL-2 and IL-12 levels offering enhanced predictive accuracy.

Cloning and Bioinformatics Analysis of Interleukin-2 of Sichuan White Goose

[Objective] The study aimed to clone interleukin-2(IL-2) gene from Sichuan white goose. [Method] Based on the IL-2 gene of duck accessed in GenBank, a pair of primers was designed for cloning IL-2 gene from total RNA of peripheral blood lymphocytes of Sichuan white goose stimulated by ConA via RT-PCR technology. The yielded fragment was sequenced for bioinformatics analysis. [Result] The full length of IL-2 gene of Sichuan white goose is 468 bp that contains a 441 bp open reading frame(ORF), encoding 146 amino acid residues. Bioinformatics analysis shows that the amino acid sequence of IL-2 gene of Sichuan white goose contains four phosphorylation sites, a glycosylation site and a signal peptide with 21 amino acid residues. Homologies of IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and duck, chicken, turkey are 92.7%, 77.5%, 78.2% and 85.8%, 65.5%, 64.1%, respectively. By contrast IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and mammalian and rodents such as human, monkey, rat, bovine, horse, pig, cat, mouse, rabbit and deer, are all less than 45% and 28%, respectively. [Conclusion] The IL-2 gene of Sichuan white goose has closer genetic relationship with those of chicken and duck.

Serum soluble interleukin-2 receptor levels in patients with chronic hepatitis B virus infection and its relation with antiHBc

AIM： To investigate the relationship between serum soluble interleukin-2 receptor （sIL-2R） level and anti-HBc in patients with chronic hepatitis B virus （HBV） infection. METHODS： Sera from 100 patients with chronic HBV infection and 30 healthy controls were included in this study. The patients were divided into group A [HBsAg （＋）, HBeAg （＋） and anti-HBc （＋）, n = 50] and group B [HBsAg （＋）, HBeAg （＋） and anti-HBc （-）, n = 50]. sIL-2R levels were determined using ELISA. HBV DNA and alanine aminotransferase （ALT） were also detected. RESULTS： Serum sIL-2R levels were significantly higher in patients with chronic HBV infection than in healthy controls. Moreover, serum sIL-2R levels were significantly higher in patients with HBsAg （＋）, HBeAg （＋） and antiHBc （＋） （976.56±213.51×10^3 U/L） than in patients with HBsAg （＋）, HBeAg （＋） and anti-HBc （-） （393.41±189.54 ×10^3 U/L, P〈 0.01）. A significant relationship was found between serum sIL-2R and ALT levels （P〈 0.01） in patients with chronic HBV infection, but there was no correlation between sIL-2R and HBV DNA levels. The anti-HBc status was significantly related to the age of patients （P〈 0.01）. CONCLUSION： The high sIL-2R level is related to positive anti-HBc in chronic hepatitis B patients. Positive anti-HBc may be related to T-lymphocyte activation and negative anti-HBc may imply immune tolerance in these patients.

Changes in soluble interleukin-2 receptor level in serum and Na^+ -K^+ -exchanging ATPase activity in semen of infertile men caused by antisperm antibody

Aim: To explore the possible mechanisms of male infertility caused by antisperm antibody (AsAb). Methods: Thesoluble interleukin-2 receptor (sIL-2R) level in serum was analyzed by ELISA and Na^+ -K^+ -exchanging ATPase activi-ty in semen by phosphorus (Pi) assay. Results: The slL-2R level in serum was significantly higher and the Na^+ -K^+ -exchanging ATPase activity in semen significantly lower in AsAb positive infertile men when compared with thecontrols. Conclusion: The AsAb titer varies with the slL-2R level in serum. A decrease in Na^+ -K^+ -exchangingATPase activity in semen may play a role in male infertility caused by AsAb.

Porcine Interleukin-2 Expression in Insect Cells and Its Enhancement of Pig Immunity to Swine Influenza Virus Inactivated Vaccine

Mature porcine interleukin-2 （pIL-2） gene was amplified by PCR from the plasmid pGEM-T-pIL2 and cloned into the baculovirus pFastBacTM Dual vector of the Bac-to-Bac baculovirus expression system under the control of the PH promoter. Recombinant plL-2 （rpIL-2） expressed in Sf9 insect cells was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunofluorescence assay. Western blot analysis confirmed that the rpIL-2 protein had a molecular mass of 20 kDa, which was larger than the molecular mass of the mature protein predicted based on its peptide sequence. The rpIL-2 protein induced in vitro proliferation of ConA-stimulated porcine splenocytes and enhanced in vivo protective immune responses induced by vaccinating the pigs with inactivated oil emulsion vaccine against swine influenza virus. The results showed that the rpIL-2 expressed in Sf9 insect cells has immunoenhancement effects; the finding lays the foundation for the preparation of a specific recombinant IL-2 protein and the development of a novel immune adjuvant of vaccines against various infectious porcine pathogens to increase the immunoprotective efficacy of vaccines.

Study of the Effect of Leeching on Plasma Endothelin and Soluble Interleukin-2 Receptor in Patients with Systemic Lupus Erythematosus

Objective: to explore the mechanism of leeching in treating systemic lupus erythematosus (SLE). Methods: Forty-four patients with SLE were randomly divided into conventional corticosteroid treated group (control group, n =20) and conventional treatment group with leeching intervention added (leeching group, n =24). Before and after treatment the concentration of plasma endothelin (ET) and soluble interleukin-2 receptor (sIL-2R) were determined. Results: Before treatment the level of plasma ET and sIL-2R in the SLE patients were all higher than those in the normal healthy group, ( P <0.01). But after treatment the level of these in both groups were significantly improved than those of before treatment ( P <0.05), and comparison between these two treated groups showed that the difference between them was significant ( P <0.05). Conclusion: Leeching added to conventional treatment of SLE could be more effective in improving the level of plasma ET and sIL-2R, and ameliorating the impairment of renal tissues.

Effects of Aprotinin on Serum Interleukin-2 and Soluble Interleukin-2 Receptor during Cardiopulmonary Bypass

Interleukin-2 and its receptor are of importance in regulating immunity responses. The changes of interleukin-2 (IL-2) and soluble interleukin-2 receptor (IL-2R) during heart valve (s) replacement operation and effects of aprotinin on them were observed. Twenty patients undergoing heart valve (s) replacement were randomly divided into two groups: control group (n=10) and apro- tinin group (n=10). In aprotinin group, 1 000 000 KIU aprotinin was given by vein injection and then 2 000 000 KIU was given as a bolus in prime. Blood samples were collected before CPB, right after CPB and on the 1st, 3rd and 7th postoperative day (POD) for serum IL-2 and sIL-2R determination. Results showed that after CPB, IL-2 was reduced and slL-2R increased. Meanwhile, serum IL-2R was lower in aprotinin group than that of control. It is concluded that the immunity depression after CPB is associated with low level of IL-2 and high level of sIL-2R and aprotinin can ameliorate the situation.

Assessment of natural and interleukin-2-induced production of interferon-gamma in patients with liver diseases

AIMS To clarify whether the lower interferon gamma (IFNγ) production by lymphocytes in patients with liver diseases is due to defects of lymphocytes themselves or of other cofactors such as interleukin-2(IL-2). METHODS Peripheral blood mononuclear cells (PBMCs) from patients with various liver diseases were cultured with or without PHA and IL-2. The cells were harvested and counted and the su- pernatants were tested for IFNγ by a sensitive and quantitative ABC-ELISA. RESULTS IFNγ was not round in serum samples from patients as well as normal individuals. However,in supernatants of non-in- duced and induced PBMCs,IFN7 was detected by ABC-ELISA. In non-induced PBMCs (group 1),the content of IFNγ in super- natants from control,CAH,CPH and HCC was 8.72 μg/L, 5.03 μg/L,6.02 μg/L and 4.91 μg/L respectively. The pro- duction of IFNγ in liver disease was significantly decreased,com- pared to control. In group 2 in which PBMCs were stimulated with PHA,the content of IFNγ was 22.71,17.12,14.54 and 17.63 μg/L respectively. In group 3 in which PBMCs were in- duced by IL-2,the amount of IFN7 in supernatant from control (60.67 μg/L) was much larger than those from CAH (21.70 μg/ L),CPH (24.00 μg/L) and HCC (19.15 μg/L) (P<0.01). Comparing the amount of IFNγ in group 3 (IL-2-induced) with that in group 1 (non-induced),we found that IFNγ production was en- hanced by nearly 4 folds in liver diseases and by over 7 folds in control,Whereas the number of PBMCs,whether from liver dis- eases or from control,was increased by only approximately 3 folds. CONCLUSIONS The decreased production of IFNγ in liver dis- eases including HCC is mainly due to endogenous defects of lym- phocytes though the defects of stimulating cofactors such as IL-2 may also be involved.

Serum Levels of Interleukin-2 and -10 in Patients with Early Syphilis

Objective: To investigate the roles of interleukin-2(IL-2) and interleukin-10 (IL-10) in pathogenesis ofearly syphilis. Methods: The serum levels of IL-2 and IL-10 in 48patients with early syphilis were detected by ABC-ELISA. Results: (1) The level of IL-2 in the patients withearly syphilis was significantly higher than that inhealthy controls, while that of IL-10 was lower(P<0.001 and P<0.001). (2) The levels of IL-2 and IL-10 were almost identical in patients with primary andsecondary syphilis (P>0.05), as well as between dif-ferent RPR titers (P>0.05). (3) After therapy, the levelof IL-2 decreased markedly (P<0.05), while that of IL-10 increase (p>0.05). (4) A significant correlation wasfound between the serum levels of IL-2 and IL-10 (r=0.5385 P<0.05). Conclusions: Th1 up-regulation occurs in patientswith early syphilis, and plays an active role in fightingagainst TP infection.

INTERLEUKIN-2 (IL-2) PRODUCTION AND INTERLEUKIN-2 RECEPTOR EXPRESSION IN PATIENTS WITH APLASTIC ANEMIA

IL-2 production and IL-2 receptor (Tac antigen) of the peripheral blood mononuclear cells in 30 patients with aplastic anemic (AA) were studied. We found that mononuclear cells from patients produce spontaneously IL-2 in the absence of exogenous lee-tin stimulation, the proportion of Tac+ cells in mononuclear cells increased. The release of IL-2 and or Tac antigen expression were elevated in almost every patient with AA. The plasma from patients stimulate mitogen-induced blastogenesis and Tac antigen expression of normal human lymphocytes. Immunological 1 abnormalities of patients with AA possibly might represents secondary response to bone marrow depression.

Neuronal changes in the retinal ganglion cell layer following recombinant human interleukin-2 intravitreal injection in a rat model of chronically elevated intraocular pressure

Intraperitoneal injection of recombinant human interleukin-2（rhIL-2）inhibits neuronal apoptosis in the chronic ocular hypertension retinal ganglion cell layer.Intravitreous injection was performed on retinal ganglion cells in a Wistar rat model of chronically elevated intraocular pressure to observe the effects of LY294002 and AG490 on retinal ganglion cell survival,macrophage activation,and PI3K/Akt and JAK/STAT activation.The number of retinal ganglion cells in the rhIL-2 treatment group was much greater than in the normal control and phosphate-buffered saline groups.Western blot analysis revealed low Akt and STAT3 protein expression in the retina after 3-hour intravitreous injections of rhIL-2.However,protein expression was increased at 12 hours,but decreased again at 24 hours,with very low expression at 96 hours.LY294002 and AG490,which are inhibitors of the PI3K/Akt and JAK/STAT3 signal pathways,prevented upregulation of Akt and STAT3 protein expression in the retina,respectively.Intravitreous injection of rhIL-2 exhibited neuroprotective effects by decreasing retinal ganglion cell layer damage in a rat model of chronic glaucoma.These results suggest that intravitreal injection of rhIL-2 could induce the PI3K/Akt and JAK/STAT3 signaling pathways to protect retinal ganglion cells in chronically elevated intraocular pressure models.

Expression of Porcine Interleukin-2 and Porcine Interleukin-6 and Their Adjuvant Effects on Gene Deleted Vaccine of Pseudorabies Virus(TK^-/gG^-/LacZ^+)

Porcine interleukin-2 and porcine interleukin-6 cDNA sequences were cloned into the expressing vectors pET-28a and pGEX-KG respectively. They were expressed in E. coli BL21(DE3)with high-level production. The gene deleted vaccine of pseudorabies virus Ea strain(TK-/gG-/LacZ+)was mixed with the two different purified recombinant proteins each, or both, with the doses of 2, 5 or 10 μg ml-1. Ten groups of pseudorabies negative antibody swines were immuned twice with tested vaccines with different doses, or control vaccine, respectively. The antibody liters of the test groups were detected by neutralization test, and the daily weight gains of swines were calculated and analyzed statistically. In the study, all the neutralizing antibody ti-ters in test groups were higher than the control group, and the recombinant proteins appeared a dose dependent adjuvant effect. The tested vaccines with 2 μg ml-1 pIL-2 and with 10 μg ml-1 pIL-2/pIL-6 got significant and extremely significant differences, compared with the vaccines without pILs. The difference of the daily weight gain indicated the potential positive influence of pIL-2 and pIL-6 on immune protection.

EFFECT OF METAL IONS ON ACTIVITY OF INTERLEUKIN-2

1 IntrodutionInterleukin-2(IL-2)was found to selectively keep growth of T lymphocytes for longperiod in vitro in 1976,and was then named T cell growth factor,TCGF.After that,IL-2 was found to promote proliferation of various cells,mainly including T,B,NK,and to in-crease activity of T cell and NK cell.Discovery of its surprising effect in treatment of can-cer,tumor through inducing LAK(lymphokine-activated killer cells)or activating TIL(tumor infiltrated lymphocytes)to kill cancer cell made it very attractive.Therefore it wasfound a wide application in therapy of cancer,immunodeficiency and diseases relating toinfection.However,in its application,problem was found that it had very serious side-effect,and very high dose made the side effect even more serious.The aim of this study was to find a simple way to stabilize IL-2 so as to lower the doserequired in application and in turn to solve the problem.

RESPONSES OF HUMAN FETAL SPLENOCYTES AND THYMOCYTES TO INTERLEUKIN-2: LAK ACTIVITY AND PROLIFERATION

Using cytotoxicity and thymidine uptake assays, we investigated the effects of human recombinant in-terleukin-2 (rIL-2) on the induction of lympholine-activated killer (LAK) activity and cellular proliferation in splenocytes and thymocytes from human fetuses (18-22 weeks). We observed that fetal splenocytes and thymocytes incubated with low doses of rIL-2 (10-100 U ml) developed broad antitumor activity (LAK activity) although the kinetics and magnitudes of the responses were different. It indicated the LAK precursors are present in fetal spleen and thymus. Further, rIL-2 induced a strong proliferative response in splenocytes, but not in thymocytes. On the basis of the findings, we conclude that the responses of fetal splenocytes and thymocytes to IL-2 are different.

THE ANTITUMOR ACTIVITY OF LYMPHOTOXIN AND THE EFFECT OF INTERLEUKIN-2 ON ITS FUNCTION

The effect of lymphotoxin (LT)-containing supernatant produced by lectin-stimulated human lymphocytes on tumor cells and the relation between interleukin-2 (IL-2) and LT were studied in this article. Results showed that LT-containing superna-tants had cytotoxicities on many different kinds of tumor cells from human and mice, that actinomycin D increased the LT activities on target cells and that IL-2 had the ability to increase the cytotoxicity of human PBMC on tumor cells, after being treated with LT, the target cells were more easy to kill by PBMC as well.

Fluence of Glucosidorum Tripterygii Totorum on joint and serum soluble interleukin-2 receptor in patients with ankylosing spondylitis

Objective The current study was designed to find out the effect of Glucosidorum Tripterygii Totorum (GTT) on the serum level of soluble interleukin-2 receptor (sIL-2R) in patient with ankylosing spondylitis (AS). Method 29 patients with active AS were selected to take GTT (1mg per kg) three times a day for one year. After that, its curative effect was evaluated. The serum level of sIL-2R of these patients was measured by sandwich ELISA method and was compared with that of normal subjects. Result The serum level of sIL-2R in active AS patients was obviously higher than that of the non-active AS patients. (P<0.01). The total effective rate of GTT on AS was 89.6%, while clinical relief rate 27.6%, obvious effective rate 44.8%, effective rate 17.2% and non-effective rate 10.4%. The patients’ serum level of sIL-2R after therapy was significantly lower than that before therapy except patients with no effect. (P<0.05). Conclusion GTT has positive curative effect on active AS patients and could cause obvious decrease of the serum level of sIL-2R. The serum level of sIL-2R can be used as an important index of activity of AS and as a guide of therapy.

PURGING OF BONE MARROWS CONTAMINATED WITH MYELOID LEUKEMIC CELLS BY INTERLEUKIN-2 AND LYMPHOKINE-ACTIVATED KILLER CELLS

The capability of recombinant human interleukin-2 ( rhIL-2) and lymphokine-activated killer (LAK) cells in the purging of normal human bone marrows contaminated with human myeloid leukemic cell lines was evaluated. Mixtures of normal human bone marrow mononuclear cells ( BMC) and K562 cells or HL-60 cells (at the BMCK562 ratio of 200:1, 100:1 or 20:1) were incubated with IL-2 with or without LAK cells at the BMC:LAK ratio of 1:1 for one or three days. The nubmers of residual K562 cells, BFU-E and CFU-GM were examined by clonogenic assays. In 200:1 mixture groups without LAK cells, the number of K562 colonies reduced by 50% with no loss of BFU-E and CFU-GM in one-day cultures, and no K562 colonies formed in three-day cultures with about 20% loss of BFU-E and CFU-GM. If the BMC.K562 ratios were 100:1 or 20:1 in the mktures, the leukemic cells could not be eliminated. When the mixtures were incubated with IL-2 and LAK cells, no leukemic cell colonies were detected in the 20:1 group following one-day

Effect of interleukin-2 on neurogliocyte and neuron apoptosis in rat models of acute spinal cord injury

BACKGROUND： lnterleukin-2 （IL-2） may influence the growth and survival of nerve cells following spinal cord injury and resuscitate the proliferation and maturation of oligodendrocytes. OBJECTIVE： To observe the effect of IL-2 on neuronal apoptosis of neurogliocytes at different times following acute spinal cord injury in rats. DESIGN, TIME AND SETTING： A randomized grouping trial based on cellular morphology was performed at the Institute of Traumatic Orthopedics of Shandong Province between October 2004 and January 2006. MATERIALS： A total of 72 adult, male, Sprague Dawley rats were included in this study and were divided into a control group and an IL-2 group. The Bcl-2 monoclonal antibody and TUNEL kit were purchased from Wunan Boster Biological Technology Corporation. METHODS： Spinal cord injury was induced in all the rats by dropping a weight from a height of 25 cm onto the exposed spinal cord at vertebral levels T7-11, thus producing a mild lesion. Immediately following the modeling, the rats were injected with daily IL-2 （10 uL） intramuscularly （the IL-2 group）. Other rats received an injection of physiological saline 0.5 mL/d （the control group）. MAIN OUTCOME MEASURES： Bcl-2 immunohistochemistry was applied to detect the Bcl-protein and positive cell expression. The TUNEL method was used to count the number of apoptotic cells. RESULTS： The expression level of Bcl-2 proteins increased significantly in spinal cord tissues during the first day after acute spinal cord injury, reaching a peak on days 3 and days 8 in the control and IL-2 groups, respectively. They were more prevalent in neurogliocytes than in neurocytes, and then began to decrease on day 14. From then until day 21, less expression was detected （P 〈 0.05）. In the control group, many apoptotic cells existed after 24 hours, and most of them were gliocytes; apoptotic cells reached a peak after 3-8 days. They then decreased gradually until day 21, when a small number of cells were still available. In the IL-2 group, the number of positive cells was significantly lower than in the control group （P 〈 0.05）. CONCLUSION： The expression of Bcl-2 and the number of apoptotic cells in neurogliocytes undergo similar changes with time after acute spinal cord injury. IL-2 may upregulate the expression of Bcl-2 proteins and decrease cell apoptosis in spinal cord tissue.

High efficient mammalian expression and secretion of a functional humanized single-chain Fv/human interleukin-2 molecules

AIM： To construct and produce a recombinant bispecific humanized single-chain Fv （sFv） /Interleukin-2 （IL-2） fusion protein by using mammalian cells. METHODS： The sFv/IL-2 protein was genetically engineered, and transfected to mammalian cells to determine whether the mammalian protein folding machinery can produce and secrete active sFv/IL-2 with high efficiency. RESULTS： The fusion protein was constructed and high efficiently expressed with yields up to 102 ±4.2 mg/L in culture supernatant of the stably transfected 293 cell line. This recombinant fusion protein consisted of humanized variable heavy （VH） and light （VL） domains of monoclonal antibody （mAb） 520C9 directed against the human HER-2/neu （c-erbB2） proto-oncogene product p185, and human IL-2 connected by polypeptide linker. The fusion protein was shown to retain the immunostimulatory activities of IL-2 as measured by IL- 2-dependent cell proliferation and cytotoxicity assays. In addition to its IL-2 activities, this fusion protein also possessed antigen-binding specificity against p185, as determined by indirect ELISA using p185 positive SKOV 3ip1 cells. CONCLUSION： The large-scale preparation of the recombinant humanized sFv antibody/IL-2 fusion protein is performed with 293 cells. The recombinant humanized sFv antibody/IL-2 fusion protein may provide an effective means.of targeting therapeutic doses of IL-2 to p185 positive tumors without increasing systemic toxicity or immunogenicity.

Sequence Analysis on Interleukin-2 Gene and Interleukin-6 Gene in a Hybrid Pig

[ Objective] To understand the functions of interteukin-2 （IL-2） and interleukin-6 （IL-6） in immune response. [ Method] Peripheral lymphocytas were isolated from a hybrid pig （ Duroc x Landrace x Shandong local pig） and stimulated with canavalin A in vitro. With total RNA as templates, the IL-2 and IL-6 cDNA were amplified by the RT-PCR and sequenced, respectively. [Result] The sequence of IL-2 gene had 100.0% nucleotide homology to the published IL-2 sequences. The sequence of IL-6 gene had 99.8% -100.0% nucleotide homology to the published IL-6 sequences, and the amino acid homology was 99.1% -100.0%. [ Conclusion] NO great variation of the IL-2 gene and IL-6 gene is observed in the hybdd pig, and these results provide a basis for research about functions of IL-2 and IL-6 protein.