373677 Results for: "single-use assemblies"

Supplier: Prosci

Methylates (mono- and asymmetric dimethylation) the guanidino nitrogens of arginyl residues in several proteins involved in DNA packaging, transcription regulation, and mRNA stability. Recruited to promoters upon gene activation together with histone acetyltransferases from EP300/P300 and p160 families, methylates histone H3 at 'Arg-17' and activates transcription via chromatin remodeling. During nuclear hormone receptor activation and TCF7L2/TCF4 activation, acts synergically with EP300/P300 and either one of the p160 histone acetyltransferases NCOA1/SRC1, NCOA2/GRIP1 and NCOA3/ACTR or CTNNB1/beta-catenin to activate transcription. During myogenic transcriptional activation, acts together with NCOA3/ACTR as a coactivator for MEF2C. During monocyte inflammatory stimulation, acts together with EP300/P300 as a coactivator for NF-κ-B. Also seems to be involved in p53/TP53 transcriptional activation. Methylates EP300/P300, both at 'Arg-2142', which may loosen its interaction with NCOA2/GRIP1, and at 'Arg-580' and 'Arg-604' in the KIX domain, which impairs its interaction with CREB and inhibits CREB-dependent transcriptional activation. Also methylates arginine residues in RNA-binding proteins PABPC1, ELAVL1 and ELAV4, which may affect their mRNA-stabilizing properties and the half-life of their target mRNAs.

Supplier: Biosensis

GDNF is a glycosylated, disulfide-bonded homodimer molecule. It was first discovered as a potent survival factor for midbrain dopaminergic neurons and was then shown to rescue these neurons in animal models of Parkinson's disease. GDNF is about 100 times more efficient survival factor for spinal motor neurons than the neurotrophins. FUNCTION: Neurotrophic factor that enhances survival and morphological differentiation of dopaminergic neurons and increases their high-affinity dopamine uptake. SUBUNIT: Homodimer; disulfide-linked. SUBCELLULAR LOCATION: Secreted protein. ALTERNATIVE PRODUCTS: 2 named isoforms produced by alternative splicing. DISEASE: Defects in GDNF may be a cause of Hirschsprung disease (HSCR). In association with mutations of RET gene, defects in GDNF may be involved in Hirschsprung disease. This genetic disorder of neural crest development is characterized by the absence of intramural ganglion cells in the hindgut, often resulting in intestinal obstruction. DISEASE: Defects in GDNF are a cause of congenital central hypoventilation syndrome (CCHS); also known as congenital failure of autonomic control or Ondine curse. CCHS is a rare disorder characterized by abnormal control of respiration in the absence of neuromuscular or lung disease, or an identifiable brain stem lesion. A deficiency in autonomic control of respiration results in inadequate or negligible ventilatory and arousal responses to hypercapnia and hypoxemia. SIMILARITY: Belongs to the TGF-beta family. GDNF subfamily.

Supplier: Rockland Immunochemical

The Anti-Glut2 antibody was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). The glucose transporter GLUT2 is a transmembrane carrier protein that allows protein facilitated glucose movement across cell membranes. GLUT2 is expressed in the plasma membranes of the liver, intestine, renal tubular cells, pancreatic islet beta cells, as well as in the portal and hypothalamic areas. Due to its low affinity and high capacity, GLUT2 transports dietary sugars, glucose, galactose and fructose in high concentrations, displaying large bidirectional fluxes in and out of cells. In pancreatic beta cells, GLUT2 is essential for glucose-stimulated insulin secretion. GLUT2 expression is necessary for the physiological control of glucose-sensitive genes, and its inactivation in the liver leads to impaired glucose-stimulated insulin secretion. In the nervous system, GLUT2-dependent glucose sensing regulates feeding, thermoregulation and pancreatic islet cell mass and function, as well as sympathetic and parasympathetic activities. In humans, inactivating mutations in GLUT2 cause Fanconi–Bickel syndrome, which is characterized by hepatomegaly and kidney disease. Anti-Glut2 is ideal for researchers interested in studying glucose transport mediated by Glut2 protein in the fields of diabetes, obesity, metabolism, and neuroscience research.

Supplier: Omega Bio-Tek

Omega Bio-teks Mag-Bind SeqDTR is designed to effective and reliable removal of unincorporated terminators from sequencing reaction. The system combines Omega Bio-teks proprietary chemistry with the reversible nucleic acid-binding properties of paramagnetic beads to eliminate excess nucleotides, primers, salts, and unicorporated dye terminators.

Supplier: BioVendor

Cyclophilins belong to a group of proteins that have peptidyl-prolyl cis-trans isomerase activity; such proteins are collectively known as immunophilins and also include the FK-506-binding proteins and the parvulins. Cyclophilins are found in all cells of all organisms studied, in both prokaryotes and eukaryotes. Human have a total of 16 cyclophilin proteins. Cyclophilins also have varying degrees of affinity for the immunosuppressive drug Cyclosporine A (CsA), a cyclic 11-amino-acid peptide produced by fungus Tolypocladium infantum. Cyclophilin A, in particular, is the major intracellular receptor for CsA. Cyclophilin A (CYPA) is the first member of the cyclophilins to be identified in mammals. Human genes of CYPA, also known as Cyp18, are located on chromosome 7p11.2-p13 and encode the protein, which consists of 165 amino acid residues with a relative molecular mass approximately 18 kDa. Human CYPA has an eight-stranded antiparallel β-barrel structure, with two α-helices enclosing the barrel from either side. Seven aromatic and other hydrophobic residues form a compact hydrophobic core within the barrel, usually in the area where CsA binds. A loop from Lys118 ti His126 and four β-strands (β3-β6) make up the binding site for CsA. In mammals, the CsA-CYPA complex binds to and inhibits calcineurin, a calcium-calmodulin-activated serine/threonine-specific protein phosphatase. The inhibition of calcineurin blocks the translocation of nuclear factor of activated T cells from the cytosol to the nucleus, thus preventing the transcription of genes encoding cytokines such as interleukin-2.

Supplier: IBI Scientific

Supplemental kit for IBI Tri-Isolate RNA Pure Kit when working with bacterial cells.

Supplier: Enzo Life Sciences

Rapid and complete removal of gDNA from RNA preps.

Supplier: Rockland Immunochemical

The Anti-Glut2 antibody was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). The glucose transporter GLUT2 is a transmembrane carrier protein that allows protein facilitated glucose movement across cell membranes. GLUT2 is expressed in the plasma membranes of the liver, intestine, renal tubular cells, pancreatic islet beta cells, as well as in the portal and hypothalamic areas. Due to its low affinity and high capacity, GLUT2 transports dietary sugars, glucose, galactose and fructose in high concentrations, displaying large bidirectional fluxes in and out of cells. In pancreatic beta cells, GLUT2 is essential for glucose-stimulated insulin secretion. GLUT2 expression is necessary for the physiological control of glucose-sensitive genes, and its inactivation in the liver leads to impaired glucose-stimulated insulin secretion. In the nervous system, GLUT2-dependent glucose sensing regulates feeding, thermoregulation and pancreatic islet cell mass and function, as well as sympathetic and parasympathetic activities. In humans, inactivating mutations in GLUT2 cause Fanconi–Bickel syndrome, which is characterized by hepatomegaly and kidney disease. Anti-Glut2 is ideal for researchers interested in studying glucose transport mediated by Glut2 protein in the fields of diabetes, obesity, metabolism, and neuroscience research.

Supplier: Rockland Immunochemical

Anti-Cyclin D3 antibody was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). Cyclin D3 belongs to a highly conserved cyclin family, whose members are the ultimate recipients of oncogenic signals. Cyclin D3 is a key component of the cell cycle progression machinery and induces progression through the G1 phase of the cell cycle. Cyclin D3 is expressed in nearly all proliferating cells, and shows the most broad expression pattern of all three D-type (D1-D3) cyclins. Cyclin D3 is encoded from the 6p21 chromosome region and the protein is predominantly localized in the nucleus. Once induced, cyclin D3 binds and activates its associated cyclin-dependent kinases CDK4 and CDK6. Amplification of the cyclin D3 gene and overexpression of cyclin D3 protein is seen in several human cancers. A large number of human malignancies contain lesions in pathways impacting on cyclin D3. Abnormal expression of Cyclin D3 is believed to be a driving force in several human cancers. A possible role for cyclin D3 in the malignancies of the lymphoid system is suggested by the observations that cyclin D3 gene is rearranged in several neoplastic diseases such as diffuse large B cell lymphomas or multiple myelomas. Anti-Cyclin D3 is ideal for researchers interested in Cancer Research and Immunology research.

Supplier: Rockland Immunochemical

The Anti-Glut2 antibody was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). The glucose transporter GLUT2 is a transmembrane carrier protein that allows protein facilitated glucose movement across cell membranes. GLUT2 is expressed in the plasma membranes of the liver, intestine, renal tubular cells, pancreatic islet beta cells, as well as in the portal and hypothalamic areas. Due to its low affinity and high capacity, GLUT2 transports dietary sugars, glucose, galactose and fructose in high concentrations, displaying large bidirectional fluxes in and out of cells. In pancreatic beta cells, GLUT2 is essential for glucose-stimulated insulin secretion. GLUT2 expression is necessary for the physiological control of glucose-sensitive genes, and its inactivation in the liver leads to impaired glucose-stimulated insulin secretion. In the nervous system, GLUT2-dependent glucose sensing regulates feeding, thermoregulation and pancreatic islet cell mass and function, as well as sympathetic and parasympathetic activities. In humans, inactivating mutations in GLUT2 cause Fanconi–Bickel syndrome, which is characterized by hepatomegaly and kidney disease. Anti-Glut2 is ideal for researchers interested in studying glucose transport mediated by Glut2 protein in the fields of diabetes, obesity, metabolism, and neuroscience research.

Supplier: New England Biolabs (NEB)

The Monarch spin columns S2A and tubes are a component of Monarch kits for RNA cleanup, and also offered separately for convenience and flexibility.

Supplier: Omega Bio-Tek

The Mag-Bind® Blood DNA HDQ 96 Kit is designed for rapid and reliable isolation of high-quality genomic DNA from 100-200 μL blood samples

Supplier: Prosci

Since their discovery in the early 1990's, the peroxisome proliferator activated receptors (PPARs) have attracted significant attention. This is primarily because PPARs serve as receptors for two very important classes of drugs: the hypolipidemic fibrates and the insulin sensitizing thiazolidinediones. Peroxisome proliferators are non-genotoxic carcinogens that are purported to exert their effect on cells through their interaction with members of the nuclear hormone receptor family termed PPARs. Nuclear hormone receptors are ligand-dependent intracellular proteins that stimulate transcription of specific genes by binding to specific DNA sequences following activation by the appropriate ligand. Upon binding fatty acids or hypolipidemic drugs, PPARs form heterodimers with retinoid X receptors (RXRs) and these heterodimers regulate the expression of target genes. There are 3 known subtypes of PPARs: PPAR-alpha, PPAR-delta and PPAR-gamma. Mostly target genes are involved in the catabolism of fatty acids. Conversely, PPAR-gamma is activated by peroxisome proliferators such as prostaglandins, leukotrienes and anti-diabetic thiazolidinediones and affects the expression of genes involved in the storage of the fatty acids. PPAR-gamma may also be involved in adipocyte differentiation. It has also been shown that PPARs can induce transcription of acyl coenzyme A oxidase and cytochrome P450 through interaction with specific response elements.

Supplier: BioVendor

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue-Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26. Resistin may be an important link between obesity and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulace glucose uptake. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs. Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression. Recent studies have shown that human resistin is expressed also in macrophages and may be a novel link between inflammation and insulin resistance.

Supplier: Promega Corporation

The Wizard SV Genomic DNA Purification System provides a fast, membrane-based method for preparing genomic DNA from cultured cells and tissue, including mouse tails.

Supplier: MilliporeSigma

The SpinPrep™ Gel DNA Kit enables efficient extraction of DNA fragments of 150 bp to > 12,000 bp in size from agarose gels.

Supplier: Rockland Immunochemical

CXCR4 antibody detects a G coupled -protein receptor. Human immunodeficiency virus (HIV) and related viruses require coreceptors, in addition to CD4, to infect target cells. Some G protein-coupled receptors including CCR5, CXCR4, CCR3, CCR2b and CCR8 in the chemokine receptor family, and four new human molecules GPR15, STRL33, GPR1 and V28 were recently identified as HIV coreceptors. Among them, CXCR4 (fusin, LESTR or HUMSTR) is a principal coreceptor for T-cell tropic strains of HIV-1 fusion and entry of human white blood cells. CXCR4 is also required for the infection by dual-tropic strains of HIV-1 and mediates CD-4 independent infection by HIV-2. The a-chemokine SDF-1 is the ligand for CXCR4 and prevents infection by T-tropic HIV-1. CXCR4 associates with the surface CD4-gp120 complex before HIV enters target cells. CXCR4 messenger RNA levels correlated with HIV-1 permissiveness in diverse human cell types. Antibodies to CXCR4 block HIV-1 and HIV-2 fusion and infection of human target cells. The amino-terminal domain and the second extracellular loop of CXCR4 serve as HIV biding sites. Anti-CXCR4 antibodies are ideal for investigators involved in Cytokines and Growth Factors or Infectious Disease reasearch.

Supplier: BioVendor

S100A11 (S100C; calgizzarin) was first isolated from chicken gizzard smooth muscle. Human homologue was later identified in human colorectal cancer cells and in colorectal normal mucosa, with much higher expression in the cancer cells. S100A11 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. The polypeptide chain consists of 105 amino acid residues giving molecular weight of unmodified monomeric protein 11.74 kDa. Disulphide bridge linking two monomers in the dimer via Cys-11 residues was found in its structure. The protein can be phosphorylated on some residues from which at least phosphorylation on Thr-10 causes significant structural changes. S100A11 binds to annexins A1 and A2, the DNA-dependent ATPase Rad54B, p53 and RAGE. It was proposed that up-regulated chondrocyte expression of S100A11 (as RAGE ligand) in OA cartilage and RAGE signaling through the p38 MAPK pathway promote inflammation-associated chondrocyte hypertrophy. RAGE signaling mediated by S100A11 thereby might have the potential to contribute to the progression of OA. S100A11 has also been shown to be secreted and to exert RAGE dependent signaling in human keratinocytes. S100A11 was found in many different human both normal and cancer tissues. S100A11 appears to play distinct roles depending on the tumour involved. In bladder carcinoma or renal carcinoma expression is related to tumour suppression however in prostate cancer, breast and pancreatic cancer S100A11 is thought to be a tumour promoter. S100A11 has been also indicated as one of potential biomarkers of infective endocarditis.

Supplier: Rockland Immunochemical

Nitric Oxide Synthase 1(NOS1,neuronal NOS,nNOS1) is a messenger molecule, mediating the effect of endothelium-derived relaxing factor in blood vessels and the cytotoxic actions of macrophages, and playing a part in neuronal communication in the brain. It may be involved in neuronal cell death and damage in neurological illness. nNOS1 localized to the 12q24.2 region of human chromosome 12. It splice variant, expressed in testis, that encodes an NH2-terminal truncated protein of 1098 amino acids. nNOS cDNA clones were shown to contain different 5' terminal exons spliced to a common exon 2. Genomic cloning and sequence analysis demonstrate that the unique exons are positioned within 300 bp of each other but separated from exon 2 by an intron that is at least 20 kb in length. The neuronal isoform of nitric oxide synthase is highly expressed in mammalian skeletal muscle, it suggested a specific role for NOS1 in the local metabolic inhibition of alpha-adrenergic vasoconstriction in active skeletal muscle. The novel gaseous neuromediator nitric oxide is thought to play an important role in development and plasticity. Despite this, gene-knockout mice lacking neuronal (Type I) nitric oxide synthase exhibit relatively normal brain development and behavior. This antibody is suitable for researchers interested in apoptosis research, cell death, and TNF pathways.

Supplier: New England Biolabs (NEB)

The NEBNext Poly(A) mRNA Magnetic Isolation Module is designed to isolate intact poly(A)+ RNA from previously isolated total RNA.

Supplier: Omega Bio-Tek

Omega Bio-tek’s E.Z.N.A.® PX Blood RNA Kit is designed for isolation of total RNA from blood samples stored in special preserved reagents and Paxgene tubes

Supplier: BioVendor

Uromodulin (Tamm-Horsfall protein, UMOD) is approx. 85-kDa glycoprotein that is produced in the thick ascending limb of Henle´s loop and early distal convoluted tubules of the nephron. It is a transmembrane protein, which is secreted into the urine through proteolytic cleavage of the glycosylphosphatidylinositol (GPI) anchor. It belongs to the GPI family. Healthy individuals excrete tens of miligrams of uromodulin per day, making in the most abundant protein in the urine. Uromodulin modulates cell adhesion and signal transduction by interacting with cytokines and it inhibits the aggregation of calcium crystals. By reducing calcium oxalate precipitation, uromodulin plays a protective role with respect to renal stone formation as demonstrated by recent studies on THP- deficient mice prone to nephrolithiasis. THP acts as a host defense factor against urinary tract infections induced by uropathogens such as Esherichia coli, Staphylococcus saphrophyticus, Proteus mirabilis and Klebsiela pneumonie. Uromodulin binds to type 1 fimbriae of Escherichia coli and thereby blocks colonization of urothelial cells. Tamm-Horsfall protein interacts with other molecules and cells including IL-1, IL-2, TNF, IgG, neuthrophils, lymphocytes and monocytes. Binding of uromodulin to neutrophils induces synthesis of IL-8, provokes the respiratory burst and degranulation and stimulates chemotaxis and phagocytosis. Recently, genome-wide association studies identified uromodulin as a risk factor for chronic kidney disease and hypertension. Mutations in the Uromodulin gene are associated with three autosomal dominant tubulo-interstitial nephropathies such as familial juvenile hyperuricemic nephropathy (FJHN), medullary cystic kidney disease (MCKD2) and glomerulocystic kidney disease (GCKD). These disorders are characterized by juvenile onset of hyperuricemia, gout and progressive renal failure.

Supplier: Brandtech

The LHS and LHS Flow are compact benchtop automated liquid handlers with intuitive method development software, an outstanding solution for automating common repetitive pipetting tasks. The LHS easily prepares ELISA, PCR, serial dilutions, cherry picking, aliquoting and more. Units provide all the benefits from automation with none of the complexity.

Supplier: IBI Scientific

The Total RNA Mini and Maxi Tissue Kits are specially designed for purification of total RNA from a variety of animal tissues or cells

Supplier: IBI Scientific

The Total RNA Mini and Maxi Kits are specially designed for purification of total RNA from fresh whole human blood and cultured cells

Supplier: Prosci

Interleukin-18 (IL-18) is a costimulatory factor for production of interferon-gamma (IFN-gamma) in response to toxic shock and shares functional similarities with IL-12. IL-18 is synthesized as a precursor 24kDa molecule without a signal peptide and must be cleaved to produce an active molecule. IL-1 converting enzyme (ICE; Caspase-1) cleaves pro-IL-18 at aspartic acid in the P1 position, producing the mature, bioactive peptide that is readily released from the cells. It is reported that IL-18 is produced from Kupffer cells, activated macrophages, keratinocytes, intestinal epithelial cells, osteoblasts, adrenal cortex cells and murine diencephalon. IFN-gamma is produced by activated T or NK cells and plays critical roles in the defense against microbiral pathogens. IFN-gamma activates macrophages and enhances NK activity and B cell maturation, proliferation and Ig secretion. IFN-gamma also induces expression of MHC class I and II antigens and inhibits osteoclast activation. IL-18 acts on T helper type-1 (Th1) T cells and in combination with IL-12 strongly induces them to produce IFN-gamma. Pleiotropic effects of IL-18 have also been reported, such as enhancement production of IFN-gamma and GM-CSF in peripheral blood mononuclear cells, production of Th1 cytokines, IL-2, GM-CSF, IFN-gamma in T cells and enhancement of Fas ligand expression by Th1 cells.

Supplier: Rockland Immunochemical

Anti-Nuclear receptor ROR gamma pS203 was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). Nuclear receptor ROR gamma pS203 antibody detects mouse receptor ROR gamma phosphorylated at the serine 203 position. RAR-related orphan receptor gamma is a member of the nuclear receptor family of transcription factors. (ROR-gamma) is a key regulator of cellular differentiation, immunity, peripheral circadian rhythm as well as lipid, steroid, xenobiotics and glucose metabolism. ROR-gamma regulates the circadian expression of clock genes such as CRY1, ARNTL/BMAL1 and NR1D1 in peripheral tissues and in a tissue-selective manner. It is also involved in the regulation of the rhythmic expression of genes involved in glucose and lipid metabolism and is a negative regulator of adipocyte differentiation. It controls adipogenesis as well as adipocyte size and modulates insulin sensitivity in obesity. Isoform 2, ROR-gamma is essential for lymphoid organogenesis, in particular lymph nodes and Peyer's patches. ROR-gamma also plays an important regulatory role in thymopoiesis, and in inhibiting apoptosis of undifferentiated T cells. Anti-nuclear receptor ROR gamma pS203 is ideal for researcher's interested in autoimmune diseases such as psoriasis and rheumatoid arthritis, circadian rhythms, and immune system disorders.

Supplier: Labconco

Ideal for biology, microbiology, biochemistry, pharmaceutical research, and analytical chemistry laboratories, centrifugal concentrators quickly process the evaporation of multiple small samples.

Supplier: Rockland Immunochemical

Influenza A virus is a major public health threat, killing more than 30, 000 people per year in the USA. In early 2009, a novel swine-origin influenza A (H1N1) virus was identified in specimens obtained from patients in Mexico and the United States. The virus spread quickly around the world and on June 11, 2009, the World Health Organization declared it a pandemic. Influenza A virus has one of sixteen possible Hemagglutinin (HA) surface proteins and one of nine possible Neuraminidase (NA) surface proteins. The Hemagglutinin protein facilitates viral attachment while Neuraminidase is involved in viral release. These proteins also elicit immune responses that prevent infection or independently reduce viral replication. The genetic make-up of this swine flu virus is unlike any other: it is an H1N1 strain that combines a triple assortment first identified in 1998 including human, swine, and avian influenza with two new pig H3N2 virus genes from Eurasia, themselves of recent human origin. The distinct antigenic properties of the new swine influenza virus compared with seasonal influenza A (H1N1) virus suggest that human immunity against new swine influenza virus is limited, although the age distribution of reported cases suggests some degree of protection in older age groups.

Supplier: Rockland Immunochemical

Influenza A virus is a major public health threat, killing more than 30, 000 people per year in the USA. In early 2009, a novel swine-origin influenza A (H1N1) virus was identified in specimens obtained from patients in Mexico and the United States. The virus spread quickly around the world and on June 11, 2009, the World Health Organization declared it a pandemic. Influenza A virus has one of sixteen possible Hemagglutinin (HA) surface proteins and one of nine possible Neuraminidase (NA) surface proteins. The Hemagglutinin protein facilitates viral attachment while Neuraminidase is involved in viral release. These proteins also elicit immune responses that prevent infection or independently reduce viral replication. The genetic make-up of this swine flu virus is unlike any other: it is an H1N1 strain that combines a triple assortment first identified in 1998 including human, swine, and avian influenza with two new pig H3N2 virus genes from Eurasia, themselves of recent human origin. The distinct antigenic properties of the new swine influenza virus compared with seasonal influenza A (H1N1) virus suggest that human immunity against new swine influenza virus is limited, although the age distribution of reported cases suggests some degree of protection in older age groups.