The recently described property of bacteria to bind to human lymphocytes was used to distinguish between normal and chronic leukemic lymphocyte (CLL) populations. Strains of the following bacteria were used in this study: Arizona hinshawii, Escherichia coli strains 1 and 2, Bacillus globigii, Brucella melitensis, Corynebacterium diphtheriae strains 1 and 2, Corynebacterium xerosis, Sarcina lutea, Staphylococcus aureus, and Staphylococcus epidermidis. For identification of immunoglobulin-bearing lymphocytes, a strain of E. coli that did not bind to human lymphocytes was coated with anti-human light-chain antibody. Labeling of lymphocytes with bacteria was promoted by centrifugation. In the eight CLL patients studied, in which greater than 90% of the lymphocytes were leukemic cells, 52 to 77% were labeled by anti-human light-chain antibody-E. coli, 80 to 93% were labeled by Br. melitensis, and 78 to 95% were labeled by E. coli 1 compared to 11 to 24, 11 to 22, and 30 to 44%, respectively, in normal individuals, Thus, Br. melitensis, E. coli 1, and the anti-human light-chain antibody-E. coli may have diagnostic value for CLL. The percentage of the lymphocyte population that bound each of the other bacteria varied from patient to patient. Preliminary results obtained by studying the pattern of binding of E. coli 2, B. globigii, Sa. lutea, or S. aureus by leukemic lymphocytes suggest that categories of CLL patients may be distinguished by this method.

Antibodies, Anti-Idiotypic↗

PubMed1977

Identification and genetic control of the n83 and n84 allotypes of rabbit IgM.

Two additional allotypes of rabbit IgM, n83 and n84, have been identified and characterized with antisera obtained by cross immunization of rabbits with IgM. These allotypic specificities were not detected on IgG or IgA by double diffusion in agar gel and by quantitative radioprecipitin analyses. This finding implies that the specificities reside in the CH region of the mu-chain. Most of the IgM (88%) from an n83 homozygote reacted with anti-n83 Ab and most of the IgM (79%) from the net n84 homozygote reacted with anti-n84 Ab. The IgG or IgA from n83 or n84 rabbits did not precipitate to a significant extent (less than 6%) with the anti-n83 or anti-n84 Ab, respectively. That the n83 and n84 specificities are controlled at the n locus was verified by genetic analysis. Thus, four alleles are now known at the n locus, n81, n82, n83 and n84. The n locus is closely linked to the other six defined loci in the heavy chain chromosomal region and the allelic alternatives for each of the seven loci are coinherited by gene combinations called allogroups. Ten such allogroups are now defined with respect to the allele at the n locus.

Alleles↗

PubMed1977

Auto-antibody to an Ig VH region allotype: induction of anti-a1 antibody in an a1-suppressed a1a2 heterozygous rabbit.

Two a1a2 heterozygous sibling rabbits were first suppressed for the paternally inherited a1 VH region allotype and then immunized with a1 IgG. Anti-a1 antibody was detected in the serum of one of the rabbits. The anti-a1 auto-antibody reacted with the same amount of a1 IgG as did a conventional anti-a1 allo-antibody. Most of the IgG and IgM of this rabbit was of the a2 allotype and no significant amount of the a1 allotype was detected as would be expected for an a1 suppressed a1a2 heterozygous rabbit. However, allotype suppression in this rabbit is maintained by endogenous anti-allotype antibody. Rabbits with anti-allotype auto-antibody may be exploited to produce litters of heterozygous and homozygous rabbits efficiently suppressed for selected allotypes.

Animals↗

PubMed1977

Additional rabbit IgA allotypes, f69, f70, g76,g77: control by the C alphaf and C alphag loci.

Genetic and immunochemical studies have led to the identification of four additional rabbit IgA allotypes controlled by the Calphaf and Calphag loci. The folowing linkage combinations of the VHa and the 'new' alleles were observed among the populations of rabbits studied: a1f70g76, a1f69g77, and a2f69g77. Cross-reactions among g74, g76, and g77 molecules with various anti-g anti-allotype antisera indicate that the IgA-g allotypic specificities are comprised of multiple antigenic determinants. These studies provide a basis for further understanding of the evolution and gnetic control of the immunoglobulin heavy chain chromosomal region.

Alleles↗

PubMed1977

Similar cell surface antigens on hamster cells transformed by different papovaviruses.

Transformed baby hamster kidney (BHK) cells were tested for surface antigens by an immunocytoadhesion method. The cells were sensitized with rabbit antisera to cell clones transformed by polyoma or by BK virus and then rosetted with erythrocytes coated with antibody to rabbit immunoglobulin. These antisera detected common antigens on BHK cells transformed by either of three papovaviruses, polyoma, BK, or SV40, but apparently not on normal BHK cells.

Animals↗

PubMed1977

Allotype suppression at the CHn locus of IgM in heterozygous rabbits with concomitant suppression at the VHa locus of all Ig classes.

Doubly heterozygous offspring, malen83alpha1/femalen82alpha2 or malen81alpha1/femalen82alpha2, of doubly homozygous dams, n82alpha2/n82alpha2, were injected neonatally with anti-n83 or anti-n81 antibody directed to the paternal n locus allotype. In each injected rabbit, the paternal n83 or n81 allotypes were suppressed and increased amounts of the maternal n82 allotype accounted for almost all of the serum IgM. This is the first report of allotype suppression in the rabbit mediated by antibody directed toward the CH region of any Ig class. A concomitant decrease in the paternal a1 Ig allotype and a compensatory increase in the maternal a2 allotype were also found. This finding supports the concept that IgM-bearing cells are the precursors of IgG-secreting cells.

Animals↗

PubMed1977

Immune RNA-mediated transfer of tumor antigen responsiveness to unresponsive peritoneal exudate cells from tumor-bearing animals.

Peritoneal exudate cells (PEC) from mice inoculated 5 to 7 days previously with 1 X 10(6) MOPC-315 plasmacytoma cells exhibit in vitro migration-inhibitory factor reactivity to soluble tumor-associated antigens. By 10 to 14 days of tumor growth, PEC from MOPC-315-bearing mice did not elicit migration-inhibitory factor when stimulated with MOPC-315 tumor-associated antigens but were still capable of migration-inhibitory factor production when stimulated with nontumor antigens. RNA-rich extracts prepared from 5- and 6-day postgrafting tumor bearers were capable of transferring tumor antigen reactivity to both normal PEC and PEC from unresponsive MOPC-315-bearing mice. On the other hand, RNA from unresponsive tumor bearers was incapable of transferring tumor antigen reactivity to normal mouse cells.

Animals↗

PubMed1976