抗鼠隐孢子虫单克隆抗体的研究

利用鼠隐孢子虫卵囊脱囊物免疫ＢＡＬＢ／Ｃ小鼠，取脾细胞与ＳＰ２／Ｏ细胞融合，经过３￣４次有限稀释法克隆化，获得５株持续分泌抗体的杂交瘤细胞株。所获抗体均属ＩｇＧ１。ＩＦＡ检测结果表明：２Ｇ７株单抗作用于卵囊壁抗原，而ＩＡ４、２Ｅ７、３Ｇ３、４Ａ７株单抗作用于子孢子表面抗原。诱生腹水经过反复冻融、冻干及硫酸铵沉淀后，抗体活性无明显变化。５株单抗均不与贝氏隐孢子虫及柔嫩艾美尔球虫产生交叉反应，与小孢隐     

抗鸡传染性支气管炎病毒单克隆抗体的制备及其特性的研究

本实验将鸡传染性支气管炎病毒（澳大利亚Ｔ株）进行纯化，制成抗原，应用杂交瘤技术建立了５株分泌抗鸡传染性支气管炎病毒的杂交瘤细胞株，其免疫球蛋白的亚类分别属于ＩｇＧ１、ＩｇＧ３、ＩｇＭ。杂交瘤细胞分泌抗体的能力稳定，长期传代对其抗体分泌能力没有影响。５株单克隆抗体与其它１２株鸡传染性支气管炎病毒标准株之间存在不同程度的交叉反应，但对鸡新城疫病毒、传染性法氏囊病病毒、产蛋下降综合征病毒及禽流感病毒均无交叉反应。用此杂交瘤细胞制备腹水的ＥＬＩＳＡ效价为１０－６～１０－７，抗体对热的稳定性有一定的差别。抗体纯化后，经ＳＤＳ－ＰＡＧＥ凝胶电泳表明具有单克隆抗体的特征，经快速蛋白分析鉴定其纯度为８９．４９％。竞争ＥＬＩＳＡ法证明其中４株的单抗与抗原结合位点并不完全相同。采用单抗夹心ＥＬＩＳＡ法，对抗原的检测方法进行了初步探索。     

Serological Observations on Chlamydia Psittaci Infection in Finnish Dairy Herds

Chlamydial complement fixing antibodies were followed in 5 small Finnish dairy herds. All 53 animals in the herds were bled. In herds A, B, C and D the blood samples were collected in May and in the following autumn after the pasturing period and in herd E over a period of 2 years at about 1 ½-month intervals. The frequencies of positive reactions among the adults and the calves younger than 1 year did not differ significantly from each other, but there were considerable seasonal variations in the frequencies. The highest frequency was found during springtime and early summer and the lowest in autumn.     

A new freeze-dried living virus vaccine against sheep-pox

A sheep-pox virus strain has been adapted and multiplied in primary lamb kidney cell cultures. The main characteristics of the strain have been verified in vitro after clones were isolated, and the results confirmed its identity. The safety and the potency of the strain have been investigated in sheep.

The inoculation of the strain to sheep was followed by a post-vaccinal reaction materialised by a nodule at the site of inoculation and an increase of temperature by about 1°C. No reactions adversely affecting pregnancy have been noted. Immunisation was demonstrated by an increase in the level of neutralising serous antibodies and protection against the pathogenic virus. The immunity tended to decrease during the second year after primovaccination and a yearly booster vaccination appeared to be necessary. Primovaccination of lambs over 2 months of age produced a better immunity, especially when the lambs were born from vaccinated ewes.

This strain forms the active principle of a freeze-dried vaccine containing no adjuvant of the immunity.     

Maceration of plant tissue by fungi is inhibited by recombinant antipectinase antibodies

Polyclonal antiserum from mice immunized with extracellular proteins from Rhizoctonia solani inhibited pectinase and cellulase activities in cell free culture supernatants of Rhizoctonia solani. Spleen mRNA from these mice was used to construct a cDNA library from which antipectinase ScFv antibodies were isolated using phage display techniques. Soluble ScFv antibodies produced by individual clones in Escherichia coli inhibited polygalacturonase in the culture supernatants of a range of fungal pathogens, including ascomycetes, basidiomycetes, and oomycetes. The soluble antibodies also inhibited maceration of potato tissue by these pathogens.     

Potential as an aerosol vaccine of an improved Newcastle disease vaccine derived from the LaSota strain—II. In vivo studies

Aerosol administrations of RIT 4030 and other available vaccine strains have been carried out in SPF and in conventional chickens. The results indicate that the RIT 4030 and Ulster 2C strains are significantly less reactogenic than the LaSota and the Hitchner B1 strains.The RIT 4030 strain produces an immune response even when administered to chickens with maternal antibodies and induces a better protection to challenge than the Ulster 2C strain.The replication of the RIT 4030 strain in the respiratory tract will be discussed with respect to its attenuation and transmissibility.     

鸡白血病／肉瘤病毒杂交瘤细胞株的建立及其单抗特性分析

用提纯的RSV-1抗原免疫BALB/C小鼠,将其脾细胞与SP2/0癌细胞进行融合,获得10株能稳定分泌特异性抗体的杂交瘤细胞系。用间接ELISA、IFA、AGP对其生物学特性进行了分析,10株MCA均属小鼠免疫球蛋白IgG_1、R_5C_(21)a、R_5C_(22)a、R_7C(32)、R_7C(34)四株MCA与RAV-1、RAV-2、SR-RSV-A、Pr-RSV-C、RAV-50病毒株均有强交叉反应,其余6株对上述病毒反应情况不尽一致,10株单抗与REV(T株)均无交叉反应。文章还讨论了单克隆抗体在我国SPF鸡群和普通鸡群白血病检测、净化中实际应用的可能性。     

Sex determination of bovine embryos using H-Y antibodies

6 days old bovine embryos (n = 126) were obtained from 8 superovulated cows or heifers by flushing the uteri and oviducts either non-surgically or after slaughter. Part of the embryos (n = 72) (morula stages) were placed in Ham's F-10 or PBS supplemented with 10% fetal calf serum (FCS) diluted 1:1 with supernatant from the H-Y antibody producing clone and cultured at 38 degrees C, in 5% CO2/95% air and 100% humidity. Control embryos (n = 54) were cultured in H-Y antibody free medium. After culture the embryos could be separated into a blastocyst--and a morula group. A subsequent colchemid and hypotonic treatment and fixation and Giemsa staining allowed a precise karyotyping, and thus sex determination for 36 H-Y antibody treated embryos and 22 control embryos. The limiting factor for proper karyotyping was lack of metaphases, incomplete methaphases or poor preparation. Among the H-Y antibody treated embryos we found 7 males and 15 females in the blastocyst and 14 males and 0 females in the morula group. A statistical analysis of these proportions led to the conclusion that the H-Y antibody had a significant influence on the sex ratio.     

Development of an Immunobinding Assay with Monoclonal Antibodies to Diagnose Mycoplasma bovis in Semen

Veterinary Research Communications -     

Doppler evaluation of maternal and fetal vessels during normal gestation in the bitch

The aim of this work is to evaluate the haemodynamic characteristics of maternal and fetal vessels during normal pregnancy in bitches, using Colour and Pulsed wave Doppler ultrasonography, in order to obtain more information about maternal and fetal circulation. The blood waveforms of the uteroplacental arteries, aorta, caudal cava vein and umbilical cord of the fetuses were recorded weekly in 16 pregnant bitches. Also, the measurements of Peak Systolic, End Diastolic Velocities, Resistance and Pulsatility Indices were carried out. Uteroplacental blood flow was biphasic while the ones of the umbilical artery and aorta were first systolic and then diastolic. The cava showed a typical waveform of venous vessels. During gestation the EDV and PSV of fetal vessels increased (alpha<0.05) while the PI and RI of all vessels examined decreased (alpha<0.05) except for the IP of the Aorta. The Doppler ultrasonography was used to study the characteristics of maternal and fetal vessel flow and their progressive changes during pregnancy. This study can be considered a further contribution in diagnosing and monitoring high-risk pregnancies in Veterinary Medicine.