Interleukin-12 subunits p35 and p40 of Indian water buffalo (Bubalus bubalis) maintain high sequence homology with those of other ruminants

Molecular cloning, sequence, and phylogenetic analysis of T helper 1 cytokines of Pashmina goats

Cytokines play an important role in regulation of immune responses either in health or disease. In the present study, the cDNAs encoding mature Interleukin (IL)-2, interferon gamma (IFN-γ), and IL-12 p35 and p40 of Pashmina goat were cloned and sequenced. The amino acid sequence was deduced from nucleotide sequence and compared with those available in GeneBank. Mature forms of goat IL-2, IFN-γ, IL-12 p35, and IL-12 p40 composed of 135, 143, 196, and 305 amino acid residues, respectively. Comparison of amino acid sequence of goat IL-2 with sheep, buffalo, cattle, pig, camel, cat, and human sequences showed homology percentages of 100, 97.8, 96.3, 72.4, 72.4, 67.2, and 64.7, respectively. Amino acid sequence of goat IFN-γ showed 98.6, 95.8, 81.1, 81.8, 80.4, and 62.9 percent homology with sheep, bovine, pig, horse, dog, and humans, respectively. Homology ranging from 81.6 to 99% for IL-12 p35 sequences and 85.6 to 100% for IL-12 p40 sequences at amino acid level were observed across these species. Multiple sequence alignment and phylogenetic analysis of goat cytokines revealed close relationship with sheep sequence.

Identification and isolation of stimulator of interferon genes (STING): an innate immune sensory and adaptor gene from camelids

The mechanism by which type I interferon-mediated antiviral response is mounted by hosts against invading pathogen is an intriguing one. Of late, an endoplasmic reticulum transmembrane protein encoded by a gene called stimulator of interferon genes (STING) is implicated in the innate signalling pathways and has been identified and cloned in few mammalian species including human, mouse and pig. In this article, we report the identification of STING from three different species of a highly conserved family of mammals - the camelids. cDNAs encoding the STING of Old World camels - dromedary camel (Camelus dromedarius) and bactrian camel (Camelus bactrianus) and a New World camel - llama (Llama glama) were amplified using conserved primers and RACE. The complete STING cDNA of dromedary camel is 2171 bp long with a 706-bp 5' untranslated regions (UTR), an 1137-bp open reading frame (ORF) and a 328-bp 3' UTR. Sequence and phylogenetic analysis of the ORF of STING from these three camelids indicate high level of similarity among camelids and conservation of critical amino acid residues across different species. Quantitative real-time PCR analysis revealed high levels of STING mRNA expression in blood, spleen, lymph node and lung. The identification of camelid STING will help in better understanding of the role of this molecule in the innate immunity of the camelids and other mammals.

Porcine IL12A and IL12B gene mapping, variation and evidence of association with lytic complement and blood leucocyte proliferation traits

Interleukin-12, a heterodimeric cytokine consisting of glycosylated subunits of 35 and 40 kDa, is a central molecule in controlling innate as well as adaptive immunity. This study was aimed to investigate the role of IL12A and IL12B as candidate genes for immune competence in pigs. The porcine genes were screened for polymorphism and association analysis was carried out by mixed model analysis with parameters of innate immunity, in vitro haemolytic complement activity in the classical and alternative pathways, in vivo complement activation expressed as C3c serum concentration, and blood leucocyte proliferation measured in F2 animals of a pig resource population based on cross of Duroc and Berlin miniature pig (DUMI resource population). A single nucleotide polymorphism (SNP) in the promoter region (C > A) of IL12A was identified. Two SNPs were detected in intron 4 of IL12B at positions 192 (A > G) and 437 (C > T). Significant effects of IL12 genotypes on complement activity traits and mitogen-induced leucocyte proliferation were found. The IL12A and IL12B genes were assigned to chromosome13 and 16, respectively, by using radiation hybrid analysis and genetic mapping in the DUMI resource population. Mapping and association analyses promote the IL12 genes as functional and positional candidate gene for disease resistance in pigs.

Comparative assessment of Th1 and Th2 cytokines of swamp type buffalo and other bubaline breeds by molecular cloning, sequencing and phylogenetics

Comparative assessment of Th1 and Th2 cytokines of three bubaline breeds namely swamp buffalo, its crossbreed with riverine buffalo (CB), and the improved breed of Bulgarian Murrah buffalo (BMB), was done by molecular cloning, sequencing and phylogenetic analysis. The Th1 cytokines analyzed included IL-2, IL-12p35, IL-12p40, and IFN-gamma while Th2 cytokines included IL-4 and IL-10. Both groups showed strict conservation in the putative secondary structures and amino acid residues within the tribe Bovini, which indicated functional cross-reactivity. Nucleotide sequence homology ranged from 98.6 to 100.0% and was lowest for IL-12p35. With regard to amino acid sequence, the lowest homology was observed in IL-4 with 97.8%. This substitution was mainly due to differences in mRNA splicing. The phylogenetic relationship of the buffalo breeds was analyzed and showed them as a cluster comprised mainly of species belonging to the order Artiodactyla, including cattle and pigs. A deeper knowledge of these cytokine structures will favor understanding of water buffalo immunology and how much it differs from its closest subspecies and other animals.

Buffalo (Bubalus bubalis) interleukin-12: Analysis of expression profiles and functional cross-reactivity with bovine system

Interleukin-12, a heterodimeric pro-inflammatory cytokine, from water buffaloes (Bubalus bubalis) was analyzed for its for its tissue specific expression and functionality. Concanavalin A stimulated splenocytes displayed an up-regulation of the IL-12 p40 subunit 8-24h post-stimulation, whereas the p35 subunit did not show any quantitative variation at different time intervals. Basal level expressions of both the subunits were observed by RT-PCR in spleen. In addition p40 transcripts could be detected in liver and p35 in brain and muscle tissues as well in very low levels. Functional recombinant buffalo IL-12 was expressed in HEK 293T cells as a heterodimer using foot-and-mouth disease virus 2A polypeptide as a linker. Culture supernatants from transfected cells contained a hetero-dimeric p70 subunit as revealed in western blot of the proteins separated by native polyacrylamide gel electrophoresis (PAGE) using a monoclonal antibody against bovine IL-12 p40. IL-12 containing culture supernatant induced production of nitric oxide in cultured splenocytes of both buffalo and bovine origin. Our study reveals that buffalo IL-12, which shares a high-level sequence identity with bovine IL-12, also has functional cross-reactivity with the bovine immune cells.

Molecular cloning and expression profile analysis of interleukin-10 and interleukin-18 cDNA of Indian water buffalo (Bubalus bubalis)

The cDNAs encoding the interleukin-10 and interleukin-18 of Indian water buffalo (Bubalus bubalis) were cloned and sequenced. A 537 bp IL-10 cDNA fragment and a 623 bp IL-18 cDNA fragment were amplified by reverse transcriptase polymerase chain reaction (RT-PCR) from concanavalin A stimulated splenocytes. Sequence analysis of these cytokines revealed high level conservation at nucleic acid and protein level. Both these cytokines also showed strict conservation in the predicted secondary structure and critical amino acid residues compared to the ruminant homologues. Basal level expression of both IL-10 and IL-18 was observed in liver, lung and spleen. The expression level of IL-10 was not affected by mitogenic stimulation, whereas IL-18 was up regulated upon stimulation. The availability of these cytokine molecules will aid in the study of their role in the immunology and pathogenesis of infections in water buffalo.