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J L Press

Publications and source records attributed to J L Press.

At least 19 recordsLinked to original sources
PubMed2000

Neonatal immunity and somatic mutation.

Neonatal animals are able to mount an effective immune response, both humoral and cellular, when immunized using conditions that maximize stimulation of antigen presenting cells, T cells, and B cells. In adults, somatic mutation is a key feature of the humoral immune response because it contributes to the generation of high affinity memory B cells. Recent evidence that B cells in neonatal mice and human infants can somatically mutate their immunoglobulin heavy chains suggests that neonates can utilize somatic mutation not only to diversify their restricted germline antibody repertoire, but also to improve upon this repertoire by the generation of B cells which can produce higher affinity antibodies. By extrapolation, if vaccination of children early in life resulted in somatic mutation and affinity maturation, this could provide a more protective antibody response to childhood diseases.

Animals↗
PubMed1998

Somatic mutation in the neonatal mouse.

Several mechanisms that diversify the adult immune repertoire, such as terminal deoxynucleotidyl transferase-dependent N region addition, are not available to the neonatal mouse. One important process that contributes to protective immunity in the adult is somatic mutation, which plays a major role in the generation of high affinity memory B cells. It is not clear whether B cells in the neonatal mouse can activate the somatic mutation machinery. To investigate this, we immunized neonates with poly(L-Tyr,L-Glu)-poly-D,L-Ala-poly-L-Lys complexed with methylated BSA, or (4-hydroxy-3-nitrophenyl)acetyl coupled to chicken gamma-globulin. Eight to fourteen days after priming, V(D)J rearrangements of known V(H) genes (V(H)SM7 family) were screened for mutations using a temperature-melt hybridization assay and oligonucleotide probes specific for complementarity-determining regions I and II; possible mutations were confirmed by sequence analysis. More mutations per sequence were found in heavy chains from neonates immunized with (4-hydroxy-3-nitrophenyl)acetyl coupled to chicken gamma-globulin than in those from neonates immunized with poly(L-Tyr,L-Glu)-poly-D,L-Ala-poly-L-Lys complexed with methylated BSA. Mutations were found in heavy chains lacking N regions, suggesting that B cells of the putative fetal lineage can somatically mutate and diversify an initially limited repertoire. Since neonates immunized as early as 1 or 2 days after birth had mutations, the somatic mutation machinery can be activated soon after birth, suggesting that early vaccination should result in affinity maturation and protective immunity in the neonate.

Animals↗
PubMed1996

Deletional mapping of fifteen mouse VH gene families reveals a common organization for three Igh haplotypes.

In addition to the content of germ-line variable gene segments, the organization of V genes has been implicated in the development of the Ab repertoire. We have searched the expressed VH genes of BALB/c mice for additional VH gene families and utilized deletion mapping to explore the extent of VH gene family interspersion. We have identified and characterized one new VH gene family (VH15) and extended our previous studies of the Igha and Ighb haplotypes to include a third haplotype (Ighj) using a newly developed panel of pre-B cell lines (CXCB cell lines). We conclude that the Igha, Ighb, and Ighj haplotypes have a similar Igh-V locus structure. A refined deletional map for 15 VH gene families and an individual member of the VHSM7 family (H10) has been constructed based on the deletion profiles of 72 rearranged heavy chain loci. These results demonstrate previously unrecognized examples of interspersion among members of the VHS107, VH10, and VHSM7 families.

Amino Acid Sequence↗
PubMed1994

A peptide sequence mimics the epitope on the multideterminant antigen (Tyr,Glu)-Ala-Lys that induces the dominant H10/V kappa 1+ primary antibody response.

The multideterminant Ag (Tyr,Glu)-Ala-Lys [(T,G)-A-L] elicits a heterogeneous secondary antibody response to different epitopes consisting of side-chain or backbone residues. However, the primary response is restricted and dominated by side-chain specific antibodies that also bind a random, linear copolymer of L-Glu and L-Tyr (GT+ antibodies), share TGB5 Id, and use the H10/V kappa 1 germ-line gene combination. We analyzed several defined sequence peptides to determine whether any might mimic the side-chain epitope(s) on (T,G)-A-L which induce the dominant Id+, H10/V kappa 1+ primary response. A carrier conjugate of the peptide TyrGluGluGluGluTyrTyrGluGluGluGluTyr (called TG4) was recognized by all the (T,G)-A-L-induced, GT+ hybridoma antibodies analyzed. In the splenic focus assay, the majority of primary and memory B cell clones induced by (T,G)-A-L produced antibodies that recognized the TG4 peptide. Mice immunized with TG4 conjugated to human gamma globulin (HGG) produced antibodies that bound (T,G)-A-L and were TGB5 Id+. Molecular analysis of Id+ primary hybridomas from TG4-HGG immunized mice showed that the antibodies used the H10 and V kappa 1 germ-line genes. Thus, the TG4 peptide can be bound by Id+, GT+ anti-(T,G)-A-L antibodies, and it induces Id+ antibodies that use the H10/V kappa 1 gene combination. By these criteria, the TG4 peptide mimics the side-chain epitope(s) on (T,G)-A-L that induces the dominant primary antibody response to that multideterminant Ag.

Amino Acid Sequence↗
PubMed1993

Molecular and kinetic analysis of an epitope-specific shift in the B cell memory response to a multideterminant antigen.

Our previous studies showed that the primary and memory B cell responses to the multideterminant antigen poly-(L-Tyr, L-Glu)-poly-D,L-Ala-poly-L-Lys ((T,G)-A-L), differ. The primary response is dominated by antibodies binding side-chain epitopes; there is little antibody response to epitopes on the poly-D,L-Ala-poly-L-Lys backbone of (T,G)-A-L. In contrast, B cells producing A-L+ antibodies constitute approximately a third of the memory response to (T,G)-A-L. To determine the basis of this epitope-specific repertoire shift, we have examined the kinetics of expression of A-L+ B cells and antibodies after in vivo antigen priming and identified VH and V kappa genes used by A-L+ hybridoma antibodies derived from primary vs memory B cells. Kinetic studies, using the splenic focus assay, showed that the clonal frequency of A-L+ B cells remains low (<3% of (T,G)-A-L-specific B cells) 1 wk after Ag priming, increases (9%) by 2 wk, but does not reach the memory frequency (30%) until at least 3 wk after immunization. Molecular analyses showed that both the primary and memory A-L+ antibody responses are heterogeneous, using different VH and V kappa gene families as well as different germ-line genes within a VH gene family. Both H and L chain gene sequences showed somatic mutations in primary as well as memory antibodies. Analysis of antibody binding patterns and somatic mutations in a set of clonally related B cells that use a new germ-line VH gene in the VGAM3.8 family (VGK7, described here), showed a direct correlation between somatic mutation and change in antibody binding specificity. Our results demonstrate how somatic mutation and Ag selection play a role in the development of the memory response to a multideterminant Ag. The data are discussed in the context of the single vs dual lineage models for memory B cell generation.

Animals↗
PubMed1991

A new germline VH36-60 gene is used in the neonatal primary and adult memory response to (T,G)-A--L.

Our previous studies of the neonatal primary response to (T,G)-A--L showed that the majority of anti-(T,G)-A--L antibodies bind the copolymer L-Glu:L-Tyr (GT), share idiotypy (Id), and use the H10 germline VH gene from the VHJ558 family and a V kappa 1 gene. We also identified two hybridomas from different neonatal donors that produced GT+, Id+ antibodies using a V kappa 1 gene with a VH gene from the VH36-60 family. In the study reported here, we show that both neonatal hybridomas use the same germline VH gene from the VH36-60 gene family. However, the VH gene sequence is different from previously identified germline genes of the VH36-60 gene family. To determine whether the expressed heavy chain gene had undergone somatic mutation, we isolated the corresponding germline gene from kidney DNA. Sequence analysis of this gene shows that it is a new member of the VH36-60 family which is not mutated in the neonatal antibodies. Furthermore, the deduced amino acid sequences of the two neonatal antibodies are identical not only in the VH region but also in the VH-D-JH joins, suggesting that there is a strong selection for CDRIII among neonatal anti-(T,G)-A--L antibodies using this germline gene (designated here as VH3A1) with a V kappa 1 gene. Also, the VH gene from the VH36-60 family that we showed previously was used by an adult memory B cell clone specific for (T,G)-A--L, can now be identified as a rearrangement of the VH3A1 germline gene. Elucidation of the germline variable region genes that are used in the antigen-specific neonatal response will help us understand the mechanisms that shape the preimmune B cell repertoire during B cell development.

Animals↗
PubMed1990

Neonatal and adult primary B cells use the same germ-line VH and V kappa genes in their (T,G)-A-L-specific repertoire.

Although there is a nonrandom usage of VH gene families by primary B cells early in ontogeny, at issue is whether the preferential rearrangement of 3' germ-line VH genes, e.g., VH7183 and VHQ52 family genes, influences the neonatal B cell repertoire that can be expressed in response to Ag. In order to address this issue, and to determine whether neonatal B cells can use the same germ-line VH and V kappa genes as adult B cells in their primary response, we have analyzed at the molecular level the neonatal antibody response to (T,G)-A-L and compared it with the adult primary response. Among the TGB5 Id+, GT+ antibodies, which dominate the neonatal response to (T,G)-A-L, two VH gene families were used: J558 (high frequency) and 36-60 (low frequency). The majority of Id+ neonatal hybridomas used the same germ-line VH gene (H10, from the VHJ558 family), but with enormous diversity in the D region, and one of two germ-line V kappa 1 genes (V kappa 1A, V kappa 1C). These are the same germ-line V-genes used by most primary adult Id+ hybridomas, and the frequency of expression of this germ-line V-gene combination appears equivalent in the neonatal and adult primary repertoires. Therefore, it is clear from this study that as early as day 5, neonatal B cells can use the same germ-line V-genes as adult primary B cells in their Ag-specific repertoire.

Amino Acid Sequence↗
PubMed1987

Molecular analysis of heavy and light chains used by primary and secondary anti-(T,G)-A--L antibodies produced by normal and xid mice.

The primary (1 degree) antibody response to (T,G)-A--L shows limited heterogeneity, consisting mostly of side chain-specific antibodies that bind GT and that express the TGB5 idiotype (Id). The secondary (2 degrees) response is very diverse: antibodies that bind the backbone A--L constitute a third of the response, and a high proportion of the side chain-specific antibodies do not bind GT and are TGB5 Id-. To provide a molecular basis for understanding this difference in repertoire expression, we analyzed the Ig genes used by heavy and light chains of 1 degree and 2 degrees side chain-specific anti-(T,G)-A--L hybridoma antibodies (HP). Southern blot restriction analysis and nucleotide sequence analysis of the expressed genes used by three TGB5 Id+ 2 degrees HP showed usage of three different VH genes in two VH gene families (36-60 and J558), different D segments, and two different Vk1 genes (the Vk1A and Vk1C subgroups). Thus, antibody heterogeneity in the 2 degrees response is contributed by combinatorial diversity of distinct germ-line genes. Nucleotide sequence analysis of the expressed genes used by TGB5 Id+ 1 degree HP showed use of highly homologous VH genes in the J558 VH gene family and highly homologous Vk1A genes. The majority of TGB5 Id+ 1 degree HP from different donors gave similar heavy and similar light chain gene rearrangements by Southern blot restriction analysis, after correction for known or potential J region differences. The combined nucleotide sequence and Southern blot restriction analysis data suggest that most 1 degree B cells use the same or very similar VH and Vk genes, i.e., the 1 degree response is paucigenic. Different D segments were used by the TGB5 Id+ 1 degree and 2 degrees HP that were sequenced, and there was no apparent correlation between TGB5 idiotypy and VH, D gene, or JH gene usage. However, all TGB5 Id+ HP sequenced used highly homologous genes from the Vk1 group. Expression of a Vk1 light chain correlates with, but is not sufficient for, TGB5 idiotypy, because one GT-binding, TGB5 Id- HP was found to use a Vk1C subgroup light chain. By Southern blot and nucleotide sequence analysis, the Vk genes used by two TGB5 Id+ 2 degrees HP from xid mice are highly homologous, if not identical to the Vk1A gene(s) used by 1 degree and 2 degrees Id+ HP from wild-type mice.

Amino Acid Sequence↗
PubMed1986

Clonal analysis of the primary and secondary B cell responses of neonatal, adult, and xid mice to (T,G)-A--L.

The splenic focus assay was used to clone B cells from neonatal, adult and xid mice in order to examine their primary and secondary responses to (T,G)-A--L. Adult precursor cell frequencies to (T,G)-A--L were achieved late in neonatal ontogeny. Primary xid B cells responded to DNP-HY but not to (T,G)-A--L in the splenic focus assay. The frequency of secondary B cells from (T,G)-A--L-primed xid mice was less than or equal to 10% that of secondary B cells from wild-type (non-xid or X/Xxid heterozygous) mice. Although xid B cells were poorly responsive to (T,G)-A--L in the splenic focus assay, (T,G)-A--L-primed xid mice could provide help as recipients for stimulation of wild-type primary and secondary B cells. It seems likely that the B2 subset contributes most of the splenic focus response to (T,G)-A--L. The fine specificities of antibodies produced by neonatal, xid, and adult (wild-type) B cell clones were analyzed using analogues of (T,G)-A--L. A specificity shift was observed between the adult primary and secondary antibody responses to (T,G)-A--L. Less than 10% of adult primary clones produced antibodies cross-reactive on (Phe,G)-A--L (recognizing A--L determinants or Phe,Glu determinants), whereas more than 70% of primary clones produced Tyr,Glu side-chain specific antibodies cross-reactive on GT. The percentage of clones producing GT-binding antibodies diminished in the secondary response, while the percentage of clones producing antibodies cross-reacting on (Phe,G)-A--L increased. Neonatal clones also produced mostly GT-binding antibodies but gave a higher percentage of (Phe,G)-A--L-cross-reacting antibodies than adult primary clones. The specificities of secondary antibodies produced by xid and wild-type B cell clones were dissimilar. First, xid secondary clones were "primary-like" in that no anti-A--L antibodies were detected. Second, clones whose antibodies bound side-chain determinants but not GT were produced in higher frequency by xid than by wild-type secondary B cells. The differential responsiveness of B cell subsets to antigen and regulatory signals may influence memory B cell generation and the specificity of antibodies produced in the primary vs secondary response.

Aging↗
PubMed1986

Xid and normal mice express a light chain-associated cross-reactive idiotype in response to (T,G)-A--L and (T,G)-A--L-mBSA.

Rabbit anti-idiotypic (Id) antibodies were prepared against purified ascites anti-(T,G)-A--L antibodies (TGB5) that had been absorbed to remove A--L-specific antibodies and were specific for (T,G)-side chain determinants. Purified rabbit anti-TGB5 Id antibodies detected an allotype-independent, light chain-associated cross-reactive Id expressed by the majority of individual mice immunized with (T,G)-A--L, (T,G)-A--L coupled to methylated bovine serum albumin (mBSA), or the linear terpolymer GAT. Primary and secondary monoclonal hybridoma protein (HP) antibodies from X/Xxid heterozygous (wild-type) mice immunized with (T,G)-A--L and/or (T,G)-A--L-mBSA were analyzed for isotypy and were grouped into eight antibody fine specificity sets defined by the patterns of direct binding to the antigens (T,G)-A--L, (Phe,G)-A--L, (T,G)-Pro--L, GT, and A--L. Analysis of these primary and secondary HP for TGB5 idiotypy showed a preferential expression of the TGB5 Id among GT+-binding HP (antibody fine specificity sets 1 through 3). All of the primary GT+-binding HP and the majority of secondary GT+-binding HP (sets 1 through 3) were TGB5 Id+. Most but not all of the TGB5 Id+ HP bound GAT. Of the side-chain-specific HP (sets 1 through 7), 78% of primary HP vs 49% of secondary HP bound GT. By these criteria, the primary HP response appears more restricted than the secondary HP response, consistent with the idea that Id diversification and antibody heterogeneity are regulated and selected events occurring during memory B cell generation. Although xid mice produce less antibody than wild-type mice to (T,G)-A--L, the TGB5 Id was produced early in the primary response by both xid and wild-type mice immunized with (T,G)-A--L or (T,G)-A--L-mBSA, and was maintained as a detectable Id in equivalent amounts in their secondary serum antibody responses. These results support the idea that distinct B cell subsets, including the xid B cell subset, share the same immunoglobulin gene repertoire.

Animals↗
PubMed1983

Monoclonal antibodies localize changes on myosin heavy chain isozymes during avian myogenesis.

Monoclonal antibodies were used to identify and localize by immunoelectron microscopy epitopes on myosin isozymes. An antibody that reacts with an amino-terminal fragment of the myosin heavy chain maps on the myosin head 140 A distal to the head-rod junction. It identifies an epitope that is shared on adult and embryonic myosin, and detects two transitions in myosin expression during avian pectoralis myogenesis. Another antibody maps to the carboxyl terminus of the myosin rod. It is specific for an adult fast myosin epitope that is not detected in early developing pectoralis muscle. In contrast, an epitope that is present throughout development is identified by an antibody that reacts with a myosin light chain. This light chain epitope is localized at the head-rod junction. These results demonstrate structural changes in widely separated regions of the myosin molecule accompanying the sequential expression of developmental myosin isozymes.

Animals↗
PubMed1982

The H-2 haplotype of a thymus graft influences the Ir gene regulated IgG3, IgG1, IgG2b, and IgG2a anti-(T,G)-A--L antibody responses of high-responder F1.nude mice.

In order to examine whether the H-2 haplotype of a thymus graft influences the levels of IgG3, IgG1, IgG2b, and IgG2a antibodies produced in an in vivo response to antigens under immune response (Ir) gene control, genotypic high-responder (H-2b X H-2k)F1.nude mice were grafted with thymuses from irradiated, neonatal low-responder (H-2k) or high-responder (H-2b or (H-2k X H-2b)F1) mice and immunized with (T,G)-A--L. All IgG antibody responses to (T,G)-A--L in high-responder mice were shown to be thymus dependent. The majority of F1.nude mice grafted with thymuses from high-responder haplotype donors produced high-responder levels of IgG anti-(T,G)-A--L antibodies. Conversely, the majority of F1.nude mice grafted with thymuses from low-responder haplotype donors gave low-responder phenotypic patterns. The modulation of the Ir gene phenotype was not restricted to a particular IgG isotype, but affected IgG3, IgG1, IgG2b, and IgG2a. The F1 . nude mice grafted with low-responder haplotype thymuses were able to produce IgG1, IgG3, and IgG2b antibodies to sheep erythrocytes, a thymus-dependent (TD) antigen not under overt Ir gene control. Circulating peripheral T cells were shown to be of host origin. By these criteria, the thymus grafts did enable F1.nude mice to respond to a TD antigen. These results support the concept that thymic H-2 determinants are involved in at least the selection of H-2 restricted T cell subsets, if not also the derivation of the T cell receptor repertoire for self and/or antigen recognition.

Animals↗
PubMed1978

Expression of murine Ia antigens during embryonic development.

An immunochemical analysis of the kinetics of appearance of Ia antigens during embryonic development was performed. Ia antigens first appear on the surface of embryonic cells 11 days postconception and their expression between days 11 and 16 of gestation is confined to the fetal liver. Ia antigen synthesis by fetal liver cells is detectable at day 14. Ia seems to precede Ig as a surface marker of embryonic liver cells, since Ig cannot be detected until day 16 of gestation. H-2 antigens may be immunoprecipitated from day 10 whole embryo cells. F9 primitive teratocarcinoma cells are Ia negative and H-2 negative.

Aging↗
PubMed1977

Allotype-specific analysis of anti-(Tyr,Glu)-Ala-Lys antibodies produced by Ir-1A high and low responder chimeric mice.

Katz et al. (1) have demonstrated a restriction in lymphoid cell interaction when the antigen used is under immune response (Ir) gene control. T cells from (low responder x high responder) F(1) mice primed to the terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) can collaborate with 2,4-dinitrophenyl (DNP)-primed B cells from the Ir-GLT high responder but not low responder strain in response to DNP-GLT (1). In contrast are the studies of Bechtol et al. and Bechtol and McDevitt (2,3), who examined the antibody responses of tetraparental mice immunized with the synthetic polypeptide poly-L(Tyr,Glu)-poly D,L-Ala- poly-L-Lys ((T,G)-A-L), an antigen under Ir-1A genetic control. Several tetraparental mice produced anti(T-,G)-A-L antibody of low responder strain immunoglobulin (Ig) allotype (2,3). These results indicated that he Ir-1A gene was not expressed in B cells and implied that interactions among genetically dissimilar cell populations could occur when tolerance existed to H-2 antigenic differences. Recent studies with bone marrow cell chimeric mice have shown that chimeric T cells can interact with H-2 histoincompatible B cells in response to antigens not under Ir gene control (4-6). To clarify whether lymphoid cell chimerism, with presumed tolerance to H-2 incompatibility, would permit effective cell interactions in response to antigens under Ir gene control, bone marrow cell chimeric mice were prepared by using strains differing both for Ig allotype and for high versus low responsiveness to (T,G)-A-L. An antigen-specific and allotype- specific antibody assay was used to discriminate the responses produced by high and low responder strain B cells in these chimeras. The results suggest that lymphoid cell chimerism per se is not sufficient to obviate Ir gene-mediated restriction in cell interaction.

Animals↗