V genes of the primary antibody response of C57BL/10 mice to the hapten phenyloxazolone

The mRNA of ten monoclonal phenyloxazolone (phOx) antibodies originating from the primary (day 7) response of C57BL/10 mice were partially sequenced. The sequences were analyzed together with those of two previously published antibodies. The C57BL response does not have a predominant subset of antibodies like the BALB/c response has (VH-Ox1/V kappa-Ox1 JK5). Probably, C57BL mice lack the VH-Ox1 gene and, as a consequence, their V kappa-Ox1 gene does not have a main role in the anti-phOx response. Five V kappa and six VH genes were found to participate. All five V kappa genes or their "alleles" had previously been found from the BALB/c response to 2-phenyloxazolone (phOx). On the other hand, the two strains use different VH genes for the anti-phOx response. Most C57BL antibodies were coded by VH genes of group 1 which has only minor role in the BALB/c response. The remaining VH genes were from group 7. Our data show that one V kappa segment (e.g. V kappa-Ox1) can code for anti-phOx antibodies with several, even widely different, VH genes. On the other hand, they emphasize the role of certain VH/VL gene combinations for the anti-phOx specificity. Thus, VH genes of group 7 were found to code for anti-phOx antibodies only together with the V kappa 45.1 gene.     

Combinatorial association of V genes: one VH gene codes for three non-cross-reactive monoclonal antibodies each specific for a different antigen (phoxazolone, NP or gat)

Two anti-phenyloxazolone (phOx3) and one anti-GAT MAbs from C57BL mice are shown to be coded by VH gene 186.2. This gene has been found earlier to code for several anti-NP (NNP) antibodies (Bothwell et al., 1981) and anti-GT antibodies (Rocca-Serra et al., 1983; Carmack and Pincus, 1986). The L chain partner of the VH 186.2 gene is different in anti-NP and anti-GAT antibodies (Bothwell et al., 1981; Rocca-Serra et al., 1983; Carmack and Pincus, 1986); in anti-phOx antibodies two new unrelated kappa chain V regions were found. Both of the new VK genes involved code frequently for anti-phOx antibodies in BALB/c mice but then with different VH genes. We tested five 186.2-coded antibodies for cross-reactions. Four antibodies were specific, one bound only to NNP, one only to phOx and two only to GT (GAT). The fifth antibody (anti-phOx) bound also to NNP, GAT and ABA-HOP though probably with a low affinity. This is the first demonstration that one V gene can code for three different antibody specificities. It emphasizes the role of the combinatorial element in antibody diversity.     

The same few V genes account for a majority of oxazolone antibodies in most mouse strains.

The early primary anti-phenyloxazolone antibodies of 12 mouse strains were studied by determining proportions of two defined subsets id495 (the classical phOx idiotype) and id350. Id495-positive antibodies bear an H chain encoded by VHOx1 gene (family Q52) and an L chain usually coded for by VKOx1 but occasionally by other VK genes. Id350-positive antibodies are encoded by a VK gene VK45.1, and usually by a VH gene of the S107 family. All 12 strains (representing nine H-chain and four kappa-chain haplotypes) produced id350-positive anti-phOx antibodies. While id495 is the predominant major subset in the BALB/c response (originally studied), id350 seems to be the predominant subset of early anti-phOx antibodies in the mouse species. The combined proportion of the two subsets varied from ca. 50 to almost 100% of the total in all strains except C57BL.     

Several V genes participate in the early phenyloxazolone response in various combinations

Seventeen monoclonal anti-2-phenyloxazolone antibodies from the early (day 7) primary response were partially sequenced with an mRNA method. Ten antibodies expressed the VH-Ox1 gene. The remaining seven express at least four but probably six different germ-line VH genes belonging to Dildrop's groups 1, 5, 6 and 7 (Immunol. Today 1984. 5: 85). Two of them have been met before in other antibodies, one (group 6) in J606 and the other (group 7) in antibodies to the influenza virus hemagglutinin. Eleven kappa chains were partially sequenced and five of them (all VH-Ox1 antibodies) express the V kappa-Ox1 gene. One expresses another germ-line gene of the V kappa-Ox1 family, one the V kappa 89.4 gene, three the V kappa 45.1 gene and one a new V kappa gene. The V kappa 45.1 gene was found to form anti-phOx antibodies with two new VH genes. The frequency of somatic mutations in day 7 antibodies was estimated by comparing germ-line sequences and antibody sequences. It is low (one mutation per 2500 nucleotides sequenced), twenty times lower than in antibodies obtained a week later. Two anti-idiotype antisera (495 and 260) are useful in the typing of monoclonal antibodies. 260 bound only to antibodies coded by both VH-Ox1 and V kappa-Ox1 genes. 495 bound strongly to antibodies coded by the VH-Ox1 gene and weakly to antibodies coded by the (related) VH101 gene regardless of the light chain partner.     

Kappa-deficient mice are non-responders to dextran B512: is this unresponsiveness due to specialization of the kappa and lambda Ig repertoires?

In the dextran B512 high-responder strain C57BL, the response to dextran is restricted to the preferential expression of the V(H)B512 and the V(kappa)OX1 gene combination. The importance of the heavy chain is suggested by the fact that mice with the Ig C(H) allotype, different from C57BL, are low or non-responders to dextran, but the light chain could also play a role. All anti-dextran B512 mAb described to date (>200) use kappa light chains. No anti-dextran antibody using lambda has ever been observed. To ascertain if the restriction of the use of V(kappa) genes in response to dextran B512 was more stochastic or due to other factors, we have studied the response to dextran B512 in C57BL/6 mice where the C(kappa) domain has been disrupted (C57BL.C(kappa)T). These mice are unable to express kappa light chains and their humoral antibodies bear light chains of the lambda type. We found that C(kappa) knockout mice are unable to respond to dextran given in a thymus-independent or -dependent form. The lack of responsiveness is specifically directed to the dextran epitopes since these mice are fully competent to respond to other antigenic structures present in the same immunogenic molecule. These mice are also apparently normal regarding the expression of V(H) genes. Finally, we tested the response to dextran in C57BL.C(kappa)T mice carrying the lpr mutation that was introduced to favor an increase in the life span and make the response to dextran more easily detectable. The introduction of the lpr mutation was not sufficient to change the pattern of unresponsiveness in the C57BL.C(kappa)T mice. We concluded that there are deficiencies in the light chain repertoire because the V lambda light chain could not reconstitute the response to dextran. We discuss the possible mechanisms for this new type of unresponsiveness to dextran B512.     

Genetic control of eosinophilia. Analysis of production and response to eosinophil-differentiating factor in strains of mice infected with Trichinella spiralis.

Bone marrow cultures were established from mice undergoing parasitic eosinophilia after infection with Trichinella spiralis. In the presence of eosinophil-differentiation factor (EDF/IL-5) eosinophil precursor cells differentiated and could be identified and counted after a 7-day in vitro culture period. The EDF-bone marrow assay system was used to determine differences in bone marrow eosinophil precursor capacity between a number of inbred strains of mice. Bone marrow cultures from high peripheral eosinophil-response phenotype strains of mice (NIH, SWR & SJL) contained significantly greater numbers of eosinophil precursor cells than the low response strain C57BL/10. All congenic strains of mice with the B10 background, i.e. C57BL/10, B10.S, B10.BR and B10.G were found to have low eosinophil precursor capacity. Bone marrow cultures obtained from F1 hybrids (NIH x C57/BL10, SJL x C57/BL10 and SWR x C57BL/10) demonstrated high precursor numbers, indicating that low responsiveness is inherited as a recessive characteristic. When spleen cells from T. spiralis-infected, high and low responder strains of mice were stimulated in vitro with concanavalin A (Con A) or with parasite antigen, it was found that low responder phenotype strains produced quantities of two eosinophilopoietic lymphokines EDF and IL3, which were similar to, if not greater than high responder strains. This suggests that bone marrow precursor capacity and not T cell lymphokine release is an important limiting factor in determining strain-dependent eosinophilia.     

Virus-induced diabetes mellitus. X. Attachment of encephalomyocarditis virus and permissiveness of cultured pancreatic beta cells to infection.

Monolayers of pancreatic β-cells from strains of mice susceptible (SJL/J) and resistant (C57BL/6J) to the development of virus-induced diabetes mellitus were inoculated with the M variant of encephalomyocarditis (EMC) virus. Immunofluorescence showed that viral antigens appeared in up to 10 times more β cells from susceptible SJL/J mice than from resistant C57BL/6J mice. Infectious center assays revealed that 10–30 times more SJL/J β cells contained infectious virus than C57BL/6J β cells. Viral attachment experiments showed no difference in the binding of EMC virus when embryonic fibroblasts, pancreatic fibroblasts, and kidney cells from SJL/J and C57BL/6J mice were compared. However, at least twice as much virus attached to the pancreatic β cells from susceptible than from resistant strains of mice. Our data suggest that genetically determined differences in viral receptors on the surface of β cells may be one of the factors controlling susceptibility to EMC-induced diabetes mellitus.     

Genetic analysis of cerebellar foliation patterns in mice (Mus musculus)

Four inbred strains of mice, DBA/2J, C57BL/10J, BALB/cJ, and SJL/J, were mated in a diallel cross. The cerebella of the F₁ generation were examined for the presence (Type I) or absence (Type II) of an intraculminate fissure between vermian lobule IV and vermian lobule V (the ventral and dorsal lobules of the culmen). One strain (DBA/2J) consistently expressed the Type I pattern. Another strain (SJL/J) expressed predominantly the Type II pattern. The other two strains (C57BL/10J and BALB/cJ) and many of the hybrids exhibited variability in their expression of the foliation patterns. The results were analyzed using biometrical genetic procedures and showed significant additive and dominance genetic effects and a maternal effect. Correlations of these cerebellar anatomical variants with the development of behavior are discussed.     

Autoimmunity to the glutamate receptor in mice--a model for Rasmussen's encephalitis?

We investigated the in vivo pathogenic potential of murine autoimmunity to peptides of the glutamate/AMPA receptor subunit 3 (GluR3). Antibodies to GluR3 are found in human epilepsy, Rasmussen's encephalitis (RE). In our accompanying paper in this issue we found that murine antibodies to the GluR3B peptide (amino acids 372-395) bind neurons in culture, evoke GluR channel activity, and kill neurons in a complement-independent excitotoxic manner, mimicking the pathophysiologic effects of excess of glutamate. In the present study, we immunized four mouse strains (BALB/c, C3H/HeJ, SJL/J and C57BL/6) with the GluR3B peptide, and investigated the development of (1) anti-GluR3B antibodies; (2) anti-GluR3 T cells; (3) clinical symptoms and abnormal behaviour; (4) brain pathology. We found that BALB/c, C3H/HeJ and SJL/J mice strains developed high titres of anti-GluR3B antibodies. The low levels anti-GluR3B antibodies raised in C57BL/6 mice suggest that the genetic background of mice influences their ability to mount a humoral autoimmune response towards the GluR3B peptide. The GluR3B-immunized mice also developed anti-GluR3B T cells, and their splenocytes showed significantly biased frequencies of particular (Vbeta11, Vbeta7 and Vbeta8) TCR Vbeta families. Surprisingly, GluR3B-immunized mice also raised high anti-ssDNA humoral immunoreactivity. GluR3B-immunized mice exhibited multiple brain pathology, partially resembling that observed in RE, and subclinical behavioral abnormalities, but no epilepsy, even upon facilitating the entry of the autoreactive antibodies into the brain, by weakening the blood-brain barrier. Taken together, these results suggest that autoimmunity to the GluR3B epitope may account for the neuronal death and brain pathology seen in neurodegenerative diseases like RE, but may not be sufficient to underly epilepsy, at least not in mice.     

Structural polymorphism of V kappa 21 E and V kappa 21 D gene products in laboratory mice

The aim of the present work was to study structural polymorphism of V kappa genes products. To this end we isolated immunoglobulins expressing the V kappa 21 D and V kappa 21 E gene products from the normal sera of several inbred strains of mice using a monoclonal antibody that selectively recognizes V kappa 21 D and V kappa 21 E subgroups. Analysis of the isoelectric focusing pattern of the light chain of these immunoglobulins revealed the existence of 3 clearly different phenotypes. The first one is shared by most inbred strains of mice, the second one is expressed by C58/J, AKR and PL/J and the third one defines V kappa 21 D-E light chains of SJL and SJA mice. Genetic analysis revealed that the locus controlling V kappa 21 D-E chain structure is closely linked to the Ly2-3 and to the Ig Kappa-Ef1 loci. Finally, using recombinant mouse strains, we could also order V kappa 21 D-E genes with respect to the known loci affecting V kappa polymorphism. Taken together our data argue against the possibility that the polymorphism observed results from strain-specific expression of V kappa genes common to all mice, but rather suggest that different allelic form of the same V kappa gene subgroup exist in different strains.     

Lack of somatic mutation in a kappa light chain transgene

Analysis of mice transgenic for immunoglobulin genes should allow definition of the cis-acting DNA sequences required to target somatic mutation to antibody V genes. We have looked for mutations in a chimeric kappa transgene encoding a V region specific for the hapten 2-phenyloxazolone (phOx) linked to a rat C kappa gene. Two independent lines of transgenic mice were hyperimmunized with phOx and splenic hybridomas established. In B cells that had been selected by antigen and which used mouse anti-phOx genes, the endogenous sequences were found to be mutated whereas the transgene remained unchanged. These results suggest either that (a) if the transgene is a "passenger" gene expressed at a low level, transgene mutation is a rare event, or that (b) sequences far from the kappa coding region are necessary to direct somatic mutation.     

Sensitivity to methylmercury-induced autoimmune disease in mice correlates with resistance to apoptosis of activated CD4+ lymphocytes

The sensitivity of splenic lymphoid cells to apoptosis induced by low concentrations of methylmercury (MeHgCl) has been examined in C57BL/6 and SJL mice, which are, respectively, resistant and sensitive to a genetically determined autoimmune disease induced by subtoxic doses of MeHgCl. To determine the implications of subtoxic doses of MeHgCl in the susceptibility of SJL mice to autoimmune disease, Concanavalin A (ConA) stimulated spleen cells from both mouse strains were treated in vitro with MeHgCl concentrations varying between 0.001 and 1.0 microM for 48h. Results have shown that ConA-activated splenic lymphoid cells from SJL mice increased in the presence of low concentrations of MeHgCl while the number of lymphoid cells from C57BL/6 mice rather decreased. Flow cytometric analysis of the cells showing a typical lymphoid forward scatter (FSC)/side scatter (SSC) pattern (region R1), and those characterized by a lower FSC and a higher SSC parameters (region R2), morphologically corresponding to apoptotic cells, revealed that lymphoid cells from C57BL/6 mice suffered a dose-dependent shift from region R1 toward region R2 when treated with concentrations ranging between 0.01 and 1 microM of MeHgCl. However, SJL splenic lymphoid cells cultured in the presence of low concentrations of MeHgCl proved more resistant to apoptosis. The level of apoptosis induced by MeHgCl in both regions was verified by AnnexinV-propidium iodide (PI) and TdT-mediated dUTP nick end labeling (TUNEL) immunolabelings. Phenotyping of lymphoid cells from both mouse strains cultured in the presence of low concentrations of MeHgCl and stimulated with ConA, indicated that CD4+ T cells from SJL mice increased while the corresponding cell subset from C57BL/6 mice became apoptotic. The resistance to apoptosis of ConA-activated lymphoid cells from SJL mice seemed related to an increase of CD4+ cells induced by the lower concentrations of MeHgCl (0.001 and 0.01 microM). However, these SJL cells were sensitive to anti-Fas-mediated apoptosis while residual anti-Fas-resistant cells from C57BL/6 mice were, themselves, sensitive to MeHgCl-induced apoptosis. The in vivo significance of these results has been confirmed by an observed increase in splenic cellularity and in the percentage of activated CD4+ cells from SJL mice. These increases were not observed in C57BL/6 mice.     

An immunoglobulin V gene polymorphism in the rat

Anti-phenyloxazolone (phOx) antibodies of different AVN rats (primary response) share several isoelectric focusing bands. These bands were not shared by antibodies of some other rat strains, including DA. An anti-idiotype reagent was prepared (in rabbits) that bound radioactive anti-phOx antibodies of AVN rats but not normal AVN immunoglobulin. This binding was strongly inhibited by AVN anti-phOx anti-sera, but not by AVN anti-BOC-p-azobenzene arsonate-tyrosine antisera or DA anti-phOx antisera. Anti-phOx antisera of (AVN x D A)F₁ rats were also strongly inhibitory indicating the presence of the idiotype (Ox-r1). Antisera of backcross rats (AVN x DA) x DA either resembled F₁ hybrid sera (31 rats) or DA sera (23 rats). The data suggest that the presence of idiotype Ox-r1 is controlled by one gene, or genes linked to each other. The gene(s) is not linked to the Ig kappa chain locus. It may be a V gene of the Ig H chain.     

Genetic variance contributes to ingestive processes: A survey of mercaptoacetate-induced feeding in eleven inbred and one outbred mouse strains

The feeding response following administration of the free fatty acid oxidation inhibitor, mercaptoacetate (MA) is conceptualized as an experimental model of lipoprivation, which may contribute to the understanding of inter-individual differences in the modulation of this homeostatic response. Although variation in the intake of food, water and glucoprivation as well as intake of several nutrients is known to be associated with genetic variation, it is not known whether MA-induced feeding is similarly dependent upon genotype. The present study therefore examined MA-induced feeding in mice of 11 inbred (A/J, AKR/J, BALB/cJ, CBA/J, C3H/HeJ, C57BL6/J, C57BL10/J, DBA/2J, SJL/J, SWR/J, 129P3/J) and one outbred (CD-1) strains across a wide range of previously determined effective MA doses (5, 35, 70, 100 mg/kg) and test times (1-4 h). MA produced significant dose-dependent and strain-dependent increases in food intake with strong responses noted in DBA/2J, outbred CD-1 and AKR/J mice. More limited dose-specific increases in food intake following MA occurred in C3H/HeJ, BALB/cJ, CBA/J, SJL/J, SWR/J and C57BL/6J mice. In contrast, MA failed to significantly increase food intake in A/J, C57BL/10J and 129P/3J mice. MA-induced food intake correlated significantly across strains only following the two highest doses, and intake following only the highest MA dose correlated significantly across strains with intake following only a moderate glucoprivic dose of 2-deoxy-d-glucose. Thus, these inter-strain differences suggest that lipoprivic (e.g., MA intake) and glucoprivic (e.g., 2-deoxy-d-glucose intake) responsivity operate via only partially overlapping genetic mechanisms of action. The demonstration of genotype-dependent variability in this lipoprivic response may provide the basis for the subsequent identification of trait-relevant genes.     

The effect of light chain gene expression on the inheritance of an idiotype associated with primary anti-(4-hydroxy-3-nitrophenyl)acetyl(NP) antibodies.

Primary anti-(4-hydroxy-3-nitrophenyl)acetyl (NP) antibodies from C57BL/6 mice were idiotypically defined by a rabbit anti-idiotypic antiserum. The idiotypic marker detected by this antiserum (the NP^b idiotype) requires for its expression a specific heavy (H) chain-lambda (Λ) light (L) chain combination as shown in chain reassociation experiments. The idiotypic binding reaction is inhibitable by hapten. BALB/c and CBA mice also produce large amounts of Λ-bearing anti-NP antibodies, but these do not express the NP^b idiotype as defined by the rabbit antiserum. Since the NP^b idiotype could be reconstituted by reassociating C57 BL/6 anti-NP antibody H chains with either HOPC 1, or BALB/c or CBA anti-NP antibody Λ chains, the absence of the NP^b idiotype in BALB/c and CBA antibodies implies that these animals express different sets of H chain variable (V) regions in the anti-NP response. SJL mice, in contrast to other mouse strains with the Ig-1^b allotype, express only traces of NP^b idiotype in their anti-NP antibodies, the L chains of which are almost exclusively of the χ type. Knowing that SJL mice possess a regulatory gene responsible for the low level of Λ (Λ¹⁰) chains in their immunoglobulins, we have analyzed the progeny of (SJL × BALB/C)F₁, (SJL × BALB/C)F₁ × BALB/C and (SJL × BALB/C)F₁ × SJL for the expression of Λ-bearing anti-NP antibodies and NP^b idiotype. In accord with previous work (SJL × BALB/c)F₁ mice produced substantial amounts of anti-NP antibodies with the NP^b idiotype. Backcross of these mice to BALB/c revealed linkage of the NP^b idiotype to the Ig-1^b allotype, in agreement with previous data. Backcross of the F₁ animals to SJL demonstrated control of the NP^b idiotype by the gene regulating Λ chain expression in serum immunoglobulin. Chain reassociation experiments showed that in SJL mice, the regulation against Λ chain expression prevents the selection in the anti-NP response of those H chains that together with Λ chains constitute the NP^b idiotype. Apparently, these H chains are unable to contribute to a binding site with specificity for the NP hapten when combined with χ chains.     

Genetic Control of Murine Antibody-Dependent Cell-Mediated Cytotoxicity

We have observed that the intensity of the direct antibody-dependent cell-mediated cytotoxicity (ADCC) response after an inoculation of foreign tumour cells varies with the strain of mice studied. The inoculation of a human lymphoblastoid cell-line into CBA/J, BALB/c, or DBA/2 mice gives rise to a good cytotoxic response by the host K cells armed with specific antibodies. In contrast, A/J, B10.A, C57BL/6 and B10.S mice respond poorly under the same conditions. The high response is dominant in Fi hybrids between high and low responders and is also expressed among F2 backcrosses with the H-2 phenotype of low responders, suggesting that non-H-2 genes are also implicated in the regulation of ADCC. The genetic control is not exerted at the level of antibody secretion but at that of K-cell activity, since sera from high or low responders are equally effective in arming an ADCC reaction, whereas K cells from low-responder strains are less efficient than those from high-responder strains. The natural killer (NK) activity of the same strains has been screened. The results show a good correlation with some high- and low-responder strains, such as CBA and DBA/2 or A/J and SJL, respectively, but not with C57BL/6, B10.S or B10.A strains. Thus, in addition to common genes controlling both lytic functions, there are specific genetic factors influencing the balance between NK and K cells. These findings confirm the general view that NK and K cells represent only partially identical subsets.     

Genetic variance contributes to ingestive processes: a survey of eleven inbred mouse strains for fat (Intralipid) intake

Genetic variation across inbred and outbred mouse strains have been observed for intake of sweet solutions, salts, bitter tastants and a high-fat diet. Our laboratory recently reported marked strain differences in the amounts and/or percentages of kilocalories of sucrose consumed among 11 inbred and one outbred mouse strains exposed to a wide range of nine sucrose concentrations (0.0001-5%) in two-bottle 24-h preference tests. To assess whether differences in fat intake were similarly associated with genetic variation, the present study examined intake of chow, water and an emulsified fat source (Intralipid) across nine different concentrations (0.00001-5%) in the same 11 inbred and 1 outbred mouse strains using two-bottle 24-h preference tests, which controlled for Intralipid concentration presentation effects, Intralipid and water bottle positions, and measurement of kilocalorie intake consumed as Intralipid or chow. Strains displayed differential increases in Intralipid intake relative to corresponding water with significant effects observed at the seven (BALB/cJ: 0.001% threshold sensitivity), four (AKR/J, C57BL/6J, DBA/2J, SWR/J: 0.5% threshold sensitivity), three (CD-1, C57BL/10J, SJL/J: 1% threshold sensitivity) and two (A/J, CBA/J, C3H/HeJ, 129P3/J: 2% threshold sensitivity) highest concentrations. In assessing the percentage of kilocalories consumed as Intralipid, SWR/J mice consumed significantly more at the three highest concentrations to a greater degree than BALB/cJ, C57BL/6J, CD-1, C3H/HeJ, DBA/J and 129P3/J strains which in turn consumed more than A/J, AKR/J, CBA/J, C57BL/10J and SJL/J mice. Relatively strong (h2 = 0.73-0.79) heritability estimates were obtained for weight-adjusted Intralipid intake at those concentrations (0.001-1%) that displayed the largest strain-specific effects in sensitivity to Intralipid. The identification of strains with diverging abilities to regulate kilocalorie intake when presented with high Intralipid concentrations may lead to the successful mapping of genes related to hedonics and obesity.     

The Hb-2d cross-reactive idiotype. A common idiotype expressed by monoclonal and polyclonal antibodies to human haemoglobin

Hb-2d is a monoclonal antibody of B10.D2 origin that is specific for the beta chain of human adult haemoglobin (HuHb-beta). Polyclonal anti-idiotypic sera to Hb-2d were produced in B10.D2, SJL/J and BALB/c mice. Using anti-idiotypic sera from SJL/J it was observed that Hb-2d expresses a cross-reactive idiotype (CRI) also found on both polyclonal and monoclonal antibodies to HuHb. Polyclonal antisera against HuHb-beta from H-2 congenic mice on the C57BL/10 (B10) background contained antibodies expressing the Hb-2d CRI; these antisera, however, contained little if any antibody to the antigenic determinant on HuHb-beta recognized by Hb-2d. Polyclonal antisera to HuHb-beta from the strains A.CA, A.SW, C3H.OL, BALB/cByJ, DBA/2 and SJL/J contained lower, but nevertheless detectable, amounts of antibody expressing the Hb-2d CRI. Unlike B10-H-2 congenic mice, antisera from the strains A.CA, A.SW and BALB/c bound to the same or a closely associated determinant as that recognized by Hb-2d. Two anti-HuHb monoclonal antibodies, Hb-48a and Hb-53a, both derived from B10-H-2 congenic mice, were shown to possess at least part of the Hb-2d idiotype. These antibodies are specific for epitopes on the human haemoglobin alpha chain (HuHb-alpha). It would appear, therefore, that Hb-2d possesses a CRI that is carried by antibodies to various antigenic determinants on HuHb. The linkage of these different antibodies by the CRI may allow for a common regulatory pathway.     

Immunologic memory to phosphorylcholine. VI. Heterogeneity in light chain gene expression

BALB/c mice immunized with phosphorylcholine-conjugated keyhole limpet hemocyanin (PC-KLH) produce two types of anti-PC antibodies, designated group I and group II, which differ in their fine specificity and idiotype expression. Group II hybridomas can utilize VH genes and VL genes (in particular, V kappa 1-3) distinct from those expressed in the group I-like anti-PC myelomas. Here we have analyzed additional anti-PC hybridomas from BALB/c and (CBA/N X BALB/c)F1 male mice and also anti-PC antibodies purified from BALB/c and C57BL/6N antisera. Isoelectric focusing indicates that one of the group II hybridomas utilizes V kappa 1-3 and that related L chains are expressed in a major portion of group II serum antibodies. Other group II antibodies in antisera express different L chains, some of which are presently unidentified. However, isoelectric focusing analysis also indicates that the L chains of some group II hybridomas and serum antibodies are related to those found in the group I anti-PC myelomas and group I hybridoma and serum antibodies. In addition, one hybridoma was found to utilize lambda 2. Thus, it appears that the anti-PC antibodies with group II-like fine specificity can utilize a variety of VL genes related to, or distinct from, those expressed in group I antibodies.