Human monoclonal antibodies to glycolipid A that exhibit complement species-specific effector functions.

Two human IgM monoclonal anti-glycolipid A antibodies (MAbs) were evaluated for their abilities to bind to various endotoxins and pathogenic gram-negative bacteria and to activate complement pathways, thereby accomplishing bactericidal and opsonic effector functions. Both MAbs cross-reacted with glycolipid A mutant lipopolysaccharides from rough colony-forming gram-negative bacteria and with selected endotoxins from smooth colony-forming bacteria. However, MAb 10235 bound to all clinical isolates of Escherichia coli and Klebsiella pneumoniae tested but only very weakly to Pseudomonas aeruginosa, whereas MAb 10058 bound to all three genera.

Human monoclonal antibodies specific for capsular polysaccharides of Klebsiella recognize clusters of multiple serotypes.

We report the generation and the characterization of a set of human monoclonal antibodies (HmAb) specific for Gram-negative bacteria of Klebsiella pneumoniae. The eight human hybridomas secrete either IgM kappa, IgA1 kappa, or IgA2 kappa antibodies. One HmAb binds bacteria of only one serotype.

Comparison of Rapid Tests Used to Detect Antibiotic Residues in Milk .

Five rapid methods for detection of antibiotics in milk were compared. The Bacillus stearothermophilus var. calidolactis disc assay was also performed on the same samples.

Systematic generation of antigen specific human monoclonal antibodies with therapeutical activities using active immunization.

Presenting a panel of human hybridomas secreting serospecific antibodies which confer a high degree of protection against fatal infection with Pseudomonas aeruginosa, we report an efficient approach for a systematic generation of antigen specific human monoclonal antibodies with biological activity. This approach is based on active immunization and antigen specific panning. Individuals were immunized with polysaccharides isolated from LPS of Pseudomonas aeruginosa conjugated to toxin A.

Influence of bovine mastitis on lipolysis ond proteolysis in milk.

Lipolysis and proteolysis in milk were determined before, during, and after experimentally induced mastitis. Streptococcus agalactiae was infused into one quarter of five cows to elicit an infection. Milk protease activity was higher during infection, but milk lipase activity was unchanged.

Selection of tests for monitoring the bacteriological quality of refrigerated raw milk supplies.

Raw milk samples were collected from 10 producer bulk tanks. Samples were then subdivided so that milks were subsequently stored at 1.7, 4.

Comparison of dry culture medium and conventional plating techniques for enumeration of bacteria in pasteurized fluid milk.

Standard plate counts, psychrotrophic bacterial counts, and coliforms were determined by conventional plating techniques and by Petrifilm TM plates, a dry culture medium, for 48 commercially processed milk samples (24 whole milk and 24 skim milk). The Petrifilm SM plate counts were compared with counts on standard methods agar for the standard plate count, psychrotrophic bacterial count, and rapid psychrotrophic bacterial count. The Petrifilm violet red bile plate counts were compared with counts on violet red bile agar for coliform test with a solid medium and the preliminary incubation method for detection of coliforms.

Recombinant tumor necrosis factor causes activation of human granulocytes.

We have tested the hypothesis that tumor necrosis factor (TNF), by binding to and activating granulocytes, may contribute to the pathogenesis of gram-negative sepsis and the adult respiratory distress syndrome (ARDS). Buffy coat granulocytes incubated with as little as 0.5 ng/mL of recombinant TNF (rTNF) showed a dose-related increase in nitroblue tetrazolium dye reduction, in granulocyte polarization, in superoxide anion release, and in visually apparent aggregation.

Variability in true protein, casein, nonprotein nitrogen, and proteolysis in high and low somatic cell milks.

Monthly variation in milk protein (total nitrogen X 6.38) and milk fat was determined for 115 farms over 2 yr. Yearly average milk protein and fat tests in each year were 3.

Human monoclonal antibodies against group A red blood cells.

A human monoclonal antibody with anti-A specificity was generated by Epstein-Barr virus transformation of lymphocytes isolated from splenic tissue after in vitro stimulation with group A red blood cells. This antibody is of the IgM class and directly agglutinates group A red blood cells. Type A1, A2, Aint, A3, AX, Aend and A5 cells were agglutinated by the reagent indicating a single determinant is shared by these A subgroups.

Characterization of human hybridomas secreting antibody to tetanus toxoid.

We have selected a thioguanine-resistant lymphoblastoid cell line (LTR228) that forms human-human hybrids with high efficiency. Fusions with peripheral B cells consistently yield one colony per 10(5) cells plated. To produce antitetanus monoclonal antibodies, we withdrew blood from persons who had recently received booster injections of tetanus toxoid.

Subpasteurization Heat Treatment to Inactivate Lipase and Control Bacterial Growth in Raw Milk.

Raw milk was heat-treated under subpasteurization and suprapasteurization conditions, cooled and stored for up to 72 h at 4.4 and 6.7°C.

Immune responses to chlamydial antigens in humans.

Antibody titer, lymphocyte stimulation and leukocyte migration inhibition with chlamydial antigens were determined repeatedly over many months on human subjects. The volunteers were retrospectively placed into four groups on the basis of clinical, laboratory and epidemiologic criteria. Group A consisted of persons with proven or probable chlamydial infection, including an illness confirmed by chlamydial isolation or seroconversion, or a clinically compatible illness with positive serologic results.

Cell-mediated and humoral immune responses to chlamydial antigens in guinea pigs infected ocularly with the agent of guinea pig inclusion conjunctivitis.

Cell-mediated immune response and humoral response to chlamydial antigens were investigated in guinea pigs infected with the agent of guinea pig inclusion conjunctivitis (GPIC). Pronounced cell-mediated immune response to the homologous antigen, as well as to two other chlamydial antigens, 6BC (Chlamydia psittaci) and LB-1 (C. trachomatis), occurred in all infected animals.

Cell-mediated immune responses to chlamydial antigens in guinea pigs injected with inactivated chlamydiae.

Cell-mediated immunity (CMI) to chlamydial antigens was readily induced in guinea pigs by a single injection of Betaprone-inactivated chlamydiae in complete Freund adjuvant. The CMI was measured in vivo by delayed hypersensitivity skin tests, and in vitro by inhibition of migration of peritoneal exudate cells and by proliferation of lymph node lymphocytes. There was an overall correlation between in vivo and in vitro responses.

Modified fluorometric determination of vitamin A in milk.

A modified fluorometric procedure for determination of vitamin A in milk was developed to provide rapid analysis of large numbers to samples.. Saponification and a single extraction in a reaction vessel without transfer provided simplicity and standardization.

In vitro correlates of delayed hypersensitivity in man: ambiguity of polymorphonuclear neutrophils as indicator cells in leukocyte migration test.

Delayed cutaneous hypersensitivity (DCH) of 12 normal adult subjects to purified protein derivative (PPD) of Mycobacterium tuberculosis, streptococcal streptokinase-streptodornase (SK-SD), and Candida albicans Dermatophytin O (DO) was assayed in vivo by skin testing and compared with such in vitro correlates of cellular immunity as lymphocyte transformation (LT) and inhibition of leukocyte migration (ILM) from microcapillary tubes or in agarose gel. LT was shown to be the best in vitro correlate of specific lymphocyte sensitization with all antigens. In the ILM assays, PPD showed good correlation with in vivo DCH and in vitro LT; SK-SD showed partial correlation; DO showed no correlation, not being active in any of the ILM tests.

The functional dissection of an antigen molecule: specificity of humoral and cellular immune responses to glucagon.

Bovine glucagon, a polypeptide of 29 amino acids, was immunogenic in guinea pigs. The immunologic determinants of glucagon were investigated using isolated tryptic peptides of the hormone. Antibodies from virtually all of more than two dozen animals had specificity primarily for the amino-terminal heptadecapeptide (NM) and showed little or no binding with the carboxy-terminal undeca- and dodecapeptides (C).

Immunogenicity of glucagon: determinants responsible for antibody binding and lymphocyte stimulation.

Bovine glucagon, a polypeptide of 29 amino acids, is immunogenic in rabbits and guinea pigs. The antigenic determinants of glucagon were investigated with isolated tryptic peptides of the hormone. Antibodies from virtually all of more than a dozen animals tested had specificity primarily for the aminoterminal heptadecapeptide.