Lymphotoxin α (LTα) signals via tumor necrosis factor receptors (TNFRs) as a homotrimer and via lymphotoxin β receptor (LTβR) as a heterotrimeric LTα1β2 complex. LTα-deficient mice lack all lymph nodes (LNs) and Peyer's patches (PPs), and yet LTβ-deficient mice and TNFR-deficient mice have cervical and mesenteric LN. We now show that mice made deficient in both LTβ and TNFR type 1 (TNFR1) lack all LNs, revealing redundancy or synergism between TNFR1 and LTβ, acting presumably via LTβR. A complete lack of only PPs in mice heterozygous for both ltα and ltβ, but not ltα or ltβ alone, suggests a similar two-ligand phenomenon in PP development and may explain the incomplete lack of PPs seen in tnfr1−/− mice.

Studies on mice genetically deficient in various secondary lymphoid organs are increasing our understanding of the requirement or otherwise for these highly organized structures in immune function, from antiviral immunity (1) to autoimmunity (2). Hox11−/− mice lack a spleen (3), whereas aly/aly mutant mice lack LNs and have a disorganized spleen (4, 5). Also, mice made deficient in the putative chemokine receptor BLR1 lack inguinal lymph nodes and fail to form primary B cell follicles in the spleen (6). Our studies have involved members of the TNF receptor and ligand families (7, 8). Studies of TNF family members are not only providing insight into the intricate microarchitecture of immune cell responses in lymphoid organs but also of chronic inflammatory states (9), such as the phenomenon termed lymphoid neogenesis (10).

TNF-α and TNF-β (lymphotoxin α; LTα)1 are the archetypal ligands of a growing family, which includes CD30 ligand (L), CD40L, FasL, TRAIL, and lymphotoxin β (LTβ) (11, 12). LTβ was discovered by virtue of its ability to anchor LTα to the cell surface, without which LTα is secreted as a homotrimer (LTα3) (13, 14). LTα/β complex itself is a trimer with a predominant form (LTα1β2) that binds LTβR, and a minor form (LTα2β1) that binds TNF receptor type 1 (TNFR1) (1517). Both forms of LTα are produced by activated lymphocytes and NK cells (12, 18).

Historically, LTα3 is known as a factor that causes cytotoxicity and inflammation, and signals via TNFR1 and TNFR2 (9, 19, 20). Although LTα/β complexes do not appear to mediate inflammation (21), pleiotropic effects of LTβR cross-linking are now emerging, including cytotoxicity (17, 22), chemokine induction (23), and integrin upregulation (21). Studies with ltα−/− mice and ltβ−/− mice are beginning to address the in vivo significance of these facets of LTα and LTβ biology (2). However, initial studies of ltα−/− mice were dominated by the unexpected observation of a complete lack of LNs and Peyer's patches (PPs), as well as a disorganized spleen lacking follicular dendritic cells and germinal centers (2427). Since mice deficient in TNFR have LNs, it had been assumed that the LTα/β complexes were responsible rather than LTα3. However, we recently showed that this explanation was not entirely correct (28). Specifically, we determined that ltβ−/− mice retain mesenteric LNs (MLNs) and to a certain extent, cervical LNs, both of which drain mucosal surfaces. It was therefore a paradox that these LNs are absent in mice that lack the LTα3 ligand and yet they are present in mice that lack the known receptors TNFR1 and TNFR2.

We now report that mice made deficient in both TNFR1 and LTβ lack MLNs. We have thus revealed a redundancy or synergism between TNFR1 and LTβ (presumably signaling via LTβR) that warrants further investigation in other aspects of TNFR1 and LTβ biology. Ltα−/− mice and ltβ−/− mice were derived as littermates by interbreeding, and unambiguously confirmed the lack of MLNs in ltα−/− mice and their presence in ltβ−/− mice. Surprisingly, the latter studies also revealed a complete and specific lack of only PPs in ltα+/−ltβ+/− mice. This presents a unique mouse model for the study of gastrointestinal immunology and suggests that two LTα ligands are involved in PP as well as MLN development, and may explain the incomplete lack of PPs seen in tnfr1−/− mice.

Materials And Methods

Mice.

ltβ−/− and ltβ+/+ wild-type mice (expanded from original littermates of ltβ−/− mice) are those described previously (28). A breeding pair of ltα−/− mice (24) was obtained from Nancy Ruddle (Yale University Department of Epidemiology and Public Health, Yale University), derived originally from David Chaplin (Washington University, St. Louis, MO). Mice deficient in both TNFR1 and TNFR2 (dtnfr−/−) represent mice derived by interbreeding tnfr1−/− mice with tnfr2−/− mice (29). Various other knockout combinations were obtained by interbreeding. All mice were on a mixed background of C57BL/6 and 129/Sv. Breeding pairs of C57BL/6 Ly5.1 (CD45.1) mice were purchased from Clarence Reeder (Frederick Cancer Research Institute, Frederick, MD). All mice were maintained at Yale University in specific pathogen-free conditions. All procedures were conducted in accordance with Yale animal care and use guidelines.

LTβ genotyping was by PCR using three oligonucleotides, yielding ∼120- and 330-bp products for the ltβ+ and ltβ alleles, respectively. The oligonucleotide sequences are: LTβfor, 5′-GAGACAGTCACACCTGTTG-3′; LTβrev, 5′-CCTGTAGTCCACCATGTCG-3′; and LTβneo, 5′-CTTGTTCAATGGCCGATCC-3′. TNFR1 and TNFR2 genotyping was by Southern blot analysis as described elsewhere (29).

Bone Marrow Chimeras.

Hosts were exposed to 950 rads at 6–8 wk of age and, 1 d later, were given 2 × 106 total nucleated bone marrow cells intravenously in 0.2 ml of PBS. Bone marrow was from sex-matched 8–12-wk-old C57BL/6 Ly5.1 mice. 8 wk after irradiation, the relative ratio of CD45.1+ donor cells versus CD45.2+ host cells in peripheral blood was determined by fluorocytometry. Both biotin-conjugated anti-CD45.1 and FITC-conjugated anti-CD45.2 were from PharMingen (San Diego, CA). The degree of chimerism was >95% in all cases. 9–10 wk after irradiation, recipients were challenged intraperitoneally with 0.1 mg of chicken γ globulin adsorbed to alum in 0.2 ml of PBS and were culled 12 d later.

Pathology.

Visualization of bracheal, axillary, inguinal, and popliteal LNs (30) was aided in some experiments by injecting 50 μl of india ink into each footpad of the mice 3–4 h before culling. The prominence of PPs was greatly increased by immersing the intestine in 10% (vol/vol) acetic acid for 5 min before preservation in 10% neutral-buffered formalin. Hematoxylin and eosin staining was done on paraffin sections using standard procedures.

Immunohistology.

Mice were challenged intraperitoneally at 6–8 wk of age with 0.1 mg of chicken γ globulin adsorbed to alum in 0.2 ml of PBS. Spleens and MLNs were harvested 12 d later and frozen in O.C.T. compound using a dry-ice/methylbutane bath. 5-μm thick sections were cut onto silanized glass slides and fixed in cold acetone for 5 min before storage at −70°C. For staining, sections were allowed to thaw for 10 min and then rehydrated in PBS for 20 min. Endogenous peroxidase was inactivated with 0.3% hydrogen peroxide for 5 min and the sections were then washed with PBS for 10 min. Blocking was with PBS/3% BSA/0.1% (vol/vol) Tween 20 for 30 min. Staining for IgD used rat anti–mouse IgD (Southern Biotechnology Associates, Birmingham, AL), followed by biotin-conjugated goat anti–rat IgG (Southern Biotechnology Associates) and then β-galactosidase– conjugated avidin (Vector Laboratories, Burlingame, CA). Washing between layers was with PBS/0.1% (vol/vol) Tween 20 before reblocking as above. Germinal centers were stained using horseradish peroxidase–conjugated peanut agglutinin (EY Laboratories, San Mateo, CA; reference 31). IgM detection was with alkaline phosphatase–conjugated goat anti–mouse IgM (Southern Biotechnology Associates). Follicular dendritic cells were revealed with biotin-conjugated anticomplement receptor 1 (PharMingen, San Diego, CA; reference 32), followed by alkaline phosphatase– conjugated streptavidin (Zymed, South San Francisco, CA). Substrates for β-galactosidase, horseradish peroxidase, and alkaline phosphatase were HistoMark X-Gal (Kirkegaard and Perry Labs., Inc., Gaithersburg, MD), diaminobenzidine-brown (Zymed), and HistoMark Red (Kirkegaard and Perry Labs., Inc.), respectively.

Results

Ltα/− Littermates of ltβ/− Mice Lack MLNs.

Initial reports of the phenotype of two independently generated ltα−/− mouse strains differed in that one indicated that MLNs were absent (24), whereas the other indicated that lymphoid structures were present in the mesentery of 4 out of 14 mice (25). Most recently, among ∼500 ltα−/− mice examined for MLNs, only 10 had a single MLN (33). It was thus suggested that the frequency of occurrence of MLNs in ltα−/− mice may vary depending on how the mice are housed (33). If true, this would perhaps apply equally to ltβ−/− mice, which we described as consistently having MLNs (28). Furthermore, Alimzhanov et al. independently generated ltβ−/− mice and found that only ∼75% of these mice have MLNs (34). It was therefore also conceivable that there are effects of background genes, although all mice examined were on a mixed background of 129/Sv and C57BL/6. The studies here were begun to examine these issues and determine why ltβ−/− mice have MLNs despite the fact that ltα−/− mice mostly do not.

The ltα and ltβ genes are separated by only ∼6 kbp in the MHC locus (12). Thus, we reasoned that it would be possible to generate ltα−/− mice and ltβ−/− mice as littermates by interbreeding mice which are heterozygous for both ltα and ltβ (ltα+/−ltβ+/− mice). In this way, 137 progeny were generated and genotyped as described in Materials and Methods. Ltα−/−, ltβ−/−, and ltα+/−ltβ+/− mice occurred in a relatively normal Mendelian fashion (n = 31, 40, and 66, respectively). Some of these mice were examined at 6–8 wk of age. Ltα−/− mice did not have MLNs (n = 14), whereas almost all of their ltβ−/− littermates did (n = 25). A single ltβ−/− mouse out of 25 appeared to lack MLNs.

Lymphotoxin Gene Dosage Effect in PP Development.

Unlike ltα−/− and ltβ−/− mice, the above heterozygous ltα+/−ltβ+/− mice had all LNs (n = 30), except that two mice had only one inguinal LN and one mouse had none. Surprisingly, however, ltα+/−ltβ+/− mice showed a complete lack of PPs (n = 30), whereas both ltα+/− mice (n = 13) and ltβ+/− mice (n = 14) have PPs as well as all LNs. Having made this observation, we examined ltα+/−ltβ+/− mice further. At 6–8 wk of age, the gross spleen architecture was normal by hematoxylin and eosin histology (data not shown). Immunohistology for complement receptor 1 in the spleen (done as previously described; reference 28) revealed the presence of follicular dendritic cells (data not shown). Also, splenic germinal centers were formed in discrete B cell follicles after intraperitoneal challenge, except there appeared to be some disorganization among IgM+IgDlo/− marginal zone B cells (Fig. 1 E). Ltα−/− mice (2428) and ltβ−/− mice (28, 34) have severe defects in all of these aspects of lymphoid organogenesis.

The organization of the MLNs of ltα+/−ltβ+/− mice was also relatively normal (Fig. 1,F). As previously noted (28), the organization of the MLNs of ltβ−/− mice is not normal in that there appears to be a generalized B cell infiltration, but B cell follicles are found around the rim of MLNs and germinal center B cell clusters are formed despite the absence of follicular dendritic cells (reference 28; Fig. 1 D).

The lack of PPs in ltα+/−ltβ+/− mice was confirmed in progeny from intercrossing ltα−/− mice with ltβ−/− mice (n = 4). Bone marrow chimeras were also generated using wild-type bone marrow, to examine whether or not the lack of PPs was reversible. None of the ltα+/−ltβ+/− recipients showed any sign of PPs 10–12 wk after irradiation, but they did have LNs (n = 9). None of the ltα−/− recipients had MLNs (n = 8), but all of the ltβ−/− recipients did (n = 11). None of the ltα−/− recipients or ltβ−/− recipients had PPs. Ltβ+/+ wild-type recipients had MLNs and PPs (n = 4).

TNFR1 Is Involved in MLN Development.

Both ltβ−/− mice and dtnfr−/− mice have MLNs, and yet ltα−/− mice do not. This led us to propose that LTα may act without LTβ (i.e., as LTα3) via an as yet unidentified receptor (28). To test this hypothesis, we generated mice lacking both LTβ and TNFR and examined them for the presence of MLNs. Since TNFR-deficient mice were originally obtained as dtnfr−/− mice, the first mice generated here were ltβ−/− dtnfr−/− mice. At 6–8 wk of age, ltβ−/−dtnfr−/− mice showed a complete lack of MLNs (n = 10), whereas ltβ+/− dtnfr−/− mice still had MLNs (n = 5).

In a similar way to ltα−/− mice, it is conceivable that the apparent absence of MLNs in ltβ−/−dtnfr−/− mice is due to a possible lack of immune competence and/or lymphocyte homing, and that this might be reversed after reconstitution with wild-type bone marrow. We therefore generated wild-type bone marrow chimeras. However, none of the bone marrow chimeras had MLNs 10–12 wk after reconstitution (n = 11).

In the meantime, we also generated ltβ−/−tnfr1−/− and ltβ−/−tnfr2−/− mice. The latter had MLNs (n = 4) but ltβ−/− tnfr1−/− mice clearly did not (n = 5). Most ltβ−/−tnfr1+/− littermates (n = 5) had one small MLN (Fig. 2). One ltβ−/− tnfr1+/− littermate did not appear to have MLNs, whereas another had two small MLNs. This may be explained by the fact that tnfr1 heterozygosity is known to result in a partial phenotype at least in some respects (35), but at the same time ltβ+/−tnfr1+/− mice had MLNs of a normal size (n = 13).

Discussion

The study reported here extends our knowledge of the roles of TNF ligand/receptor family members in lymphoid organogenesis (Table 1). Based on several observations, we had previously hypothesized that both TNFR1 and LTβR may be involved in PP development (28). First, both ltα−/− mice (24, 25) and ltβ−/− mice (28, 34) completely lack PPs. Second, Rennert et al. observed a complete lack of PPs in mice administered recombinant soluble LTβR in utero (36). Third, tnfr1−/− mice lack PPs but have reduced numbers of residual lymphoid aggregates (37). Defective PP development was also reported recently with an independently generated tnfr1−/− mouse strain (29). Others reported that tnfr1−/− mice have PPs but that they appear flattened due to a lack of B cell follicle structures (38). However, even this study noted that tnfr1−/− mice have on average only two to four such PPs compared with six to eight PPs in the wild-type control mice (38).

In this study, we show the existence of a gene dosage effect that is consistent with a role for both TNFR1 and LTβR in PP development. That is, ltα+/−ltβ+/− mice specifically lack only PPs, but ltα+/− mice and ltβ+/− mice do not. If LTα and LTβ form a single species that signals via a single receptor, it might be expected that either LTα or LTβ would be the limiting factor and that heterozygosity in either ltα or ltβ alone should result in the lack of PPs seen in ltα+/−ltβ+/− mice. However, this is not the case. Only when both ltα and ltβ are heterozygous does insufficiency become evident. One interpretation would be that two ligands (e.g., LTα3 and LTα1β2 signaling via TNFR1 and LTβR, respectively) are involved in PP development, and that heterozygosity in either one or the other alone is not enough to cause a complete loss of PP development. This two-receptor model might therefore provide an explanation for the partial defect in PP development seen in tnfr1−/− mice.

Clearly, our results show that both TNFR1 and LTβ are involved in MLN development, even though both tnfr1−/− mice and ltβ−/− mice have MLNs. TNFR1 also functions independently of TNFR2 in this regard, as ltβ−/−tnfr2−/− mice still have MLNs. We have thus revealed a previously unappreciated relationship between TNFR1 and LTβ (presumably acting via LTβR). An explanation for the lack of MLN in ltα−/− mice might therefore be that LTα deficiency actually eliminates both ligands of the relationship (i.e., LTα3 and LTα1β2 signaling via TNFR1 and LTβR, respectively). LTα3 itself is not believed to bind LTβR (16, 17).

However, having said this, it has been indicated that ltβr−/− mice lack MLNs (34). Thus, the relationship between TNFR1 and LTβR may be one of synergism with LTβR as the dominant partner. At the same time, the presence of MLN in ltβ−/− mice would imply that LTβR has a ligand besides the LTα/β complex. Indeed, Mauri et al. have very recently described a new LTβR ligand (LIGHT) as well as a new LTα3 receptor, the herpesvirus entry mediator, expressed by lymphocytes (39).

The molecular basis for the relationship between TNFR1 and LTβ (presumably via LTβR) remains to be determined. It is conceivable that TNFR1 and LTβR signaling in MLN development is simultaneous and that they interact at the level of intracellular signal transducers. Certainly, activation of LTβR has been shown to potentiate TNF-α cytotoxicity, possibly reflecting cross-talk between signaling pathways (17, 22). Ligation of LTβR causes recruitment of TNFR-associated factor family members (4042), and activation of NF-κB and cell death by distinct signaling pathways (42, 43).

Thus far, our studies of ltβ−/− mice have evaluated the defects in lymphoid organogenesis (reference 28 and this study). We are now beginning to examine whether or not LTβ has roles in vivo in other respects. Certainly, in vitro studies have shown that signaling via LTβR causes cytotoxicity to some cell lines (17, 22), chemokine expression (23), and integrin upregulation (21). It remains to be seen whether or not the relationship between TNFR1 and LTβ (presumably via LTβR) in gut-associated lymphoid tissue development extends to any other facets of biology. With this in mind, caution is advised when interpreting the in vivo role (or rather, apparent lack thereof  ) of LTβ and TNFR1 based on studies of ltβ−/− mice and tnfr1−/− mice alone.

Finally, ltα+/−ltβ+/− mice may prove to be a useful PP-less mouse model, not only for the study of gastrointestinal infection, but also of oral tolerance, oral vaccination, and chronic disorders such as inflammatory bowel disease (44– 46). Ltα+/−ltβ+/− mice are being further characterized, particularly with respect to the subtle defect observed in splenic marginal zone organization. Although it remains possible that ltα+/−ltβ+/− mice have other as yet unidentified defects, unlike any other previously described mouse, these mice specifically and completely lack only PPs and do not appear to have any of the major abnormalities associated with ltα−/− and ltβ−/− mice.

Acknowledgments

We thank Jacques Peschon (Immunex Corp., Seattle, WA) for tnfr−/− mice; Frank Wilson, Cindy Hughes, and Debbie Butkus for technical assistance; and Fran Manzo for secretarial assistance.

This work was supported by the Howard Hughes Medical Institute (R.A. Flavell) with the aid of grants from the Human Frontiers Science Program (to P.A. Koni) and the American Diabetes Association (to R.A. Flavell). Richard A. Flavell is an Investigator of the Howard Hughes Medical Institute.

Abbreviations used in this paper: dtnfr

     
  • −/−

    mice deficient in both TNFR1 and TNFR2

  •  
  • LT

    lymphotoxin

  •  
  • MLN

    mesenteric lymph nodes

  •  
  • PPs

    Peyer's patches

References

References
1
Karrer
U
,
Althage
A
,
Odermatt
B
,
Roberts
CWM
,
Korsmeyer
SJ
,
Miyamaki
S
,
Hengartner
H
,
Zinkernagel
RM
On the key role of secondary lymphoid organs in antiviral immune responses studied in alymphoplastic (aly/ aly) and spleenless (Hox11−/−) mutant mice
J Exp Med
1997
185
2157
2170
[PubMed]
2
Suen
WE
,
Bergman
CM
,
Hjelmström
P
,
Ruddle
NH
A critical role for lymphotoxin in experimental allergic encephalomyelitis
J Exp Med
1997
186
1233
1240
[PubMed]
3
Roberts
CW
,
Shutter
JR
,
Korsmeyer
SJ
Hox11controls the genesis of the spleen
Nature
1994
368
747
749
[PubMed]
4
Miyawaki
S
,
Nakamura
Y
,
Suzuka
H
,
Koba
M
,
Yasumizu
R
,
Ikehara
S
,
Shibata
Y
A new mutation, aly, that induces a generalized lack of lymph nodes accompanied by immunodeficiency in mice
Eur J Immunol
1994
24
429
434
[PubMed]
5
Shinkura
R
,
Matsuda
F
,
Sakiyama
T
,
Tsubata
T
,
Hiai
H
,
Paumen
M
,
Miyawaki
S
,
Honjo
T
Defects of somatic hypermutation and class switching in alymphoplasia (aly)mutant mice
Int Immunol
1996
8
1067
1075
[PubMed]
6
Förster
R
,
Mattis
AE
,
Kremmer
E
,
Wolf
E
,
Brem
G
,
Lipp
M
A putative chemokine receptor, BLR1, directs B cell migration to defined lymphoid organs and specific anatomic compartments of the spleen
Cell
1996
87
1037
1047
[PubMed]
7
Liu
Y-J
,
Banchereau
J
Mutant mice without B lymphocyte follicles
J Exp Med
1996
184
1207
1211
[PubMed]
8
von Boehmer
H
Lymphotoxins: from cytotoxicity to lymphoid organogenesis
Proc Natl Acad Sci USA
1997
94
8926
8927
[PubMed]
9
Sacca
R
,
Cuff
CA
,
Ruddle
NH
Mediators of inflammation
Curr Opin Immunol
1997
9
851
857
[PubMed]
10
Kratz
A
,
Campos-Neto
A
,
Hanson
MS
,
Ruddle
NH
Chronic inflammation caused by lymphotoxin is lymphoid neogenesis
J Exp Med
1996
183
1461
1472
[PubMed]
11
Smith
CA
,
Farrah
T
,
Goodwin
RG
The TNF receptor superfamily of cellular and viral proteins: activation, costimulation, and death
Cell
1994
76
959
962
[PubMed]
12
Ware
CF
,
VanArsdale
TL
,
Crowe
PD
,
Browning
JL
The ligands and receptors of the lymphotoxin system
Curr Top Microbiol Immunol
1995
198
175
218
[PubMed]
13
Androlewicz
MJ
,
Browning
JL
,
Ware
CF
Lymphotoxin is expressed as a heteromeric complex with a distinct 33-kDa glycoprotein on the surface of an activated human T cell hybridoma
J Biol Chem
1992
267
2542
2547
[PubMed]
14
Browning
JL
,
Ngam-ek
A
,
Lawton
P
,
DeMarinis
J
,
Tizard
R
,
Chow
EP
,
Hession
C
,
O'Brine-Greco
GB
,
Foley
SF
,
Ware
CF
Lymphotoxin β, a novel member of the TNF family that forms a heteromeric complex with lymphotoxin on the cell surface
Cell
1993
72
847
856
[PubMed]
15
Browning
JL
,
Dougas
I
,
Ngam-ek
A
,
Bourdon
PR
,
Ehrenfels
BN
,
Miatkowski
K
,
Zafari
M
,
Yampaglia
AM
,
Lawton
P
,
Meier
W
et al
Characterization of surface lymphotoxin forms: use of specific monoclonal antibodies and soluble receptors
J Immunol
1995
154
33
46
[PubMed]
16
Crowe
PD
,
VanArsdale
TL
,
Walter
BN
,
Ware
CF
,
Hession
C
,
Ehrenfels
B
,
Browning
JL
,
Din
WS
,
Goodwin
RG
,
Smith
CA
A lymphotoxin-β–specific receptor
Science
1994
264
707
710
[PubMed]
17
Mackay
F
,
Bourdon
PR
,
Griffiths
DA
,
Lawton
P
,
Zafari
M
,
Sizing
ID
,
Miatkowski
K
,
Ngam-ek
A
,
Benjamin
CD
,
Hession
C
et al
Cytotoxic activities of recombinant soluble murine lymphotoxin-α and lymphotoxin-αβ complexes
J Immunol
1997
159
3299
3310
[PubMed]
18
Browning
JL
,
Sizing
ID
,
Lawton
P
,
Bourdon
PR
,
Rennert
PD
,
Majeau
GR
,
Ambrose
CM
,
Hession
C
,
Miatkowski
K
,
Griffiths
DA
et al
Characterization of lymphotoxin-αβ complexes on the surface of mouse lymphocytes
J Immunol
1997
159
3288
3298
[PubMed]
19
Schoenfeld
HJ
,
Poeschl
B
,
Frey
JR
,
Loetscher
H
,
Hunziker
W
,
Lustig
A
,
Zulauf
M
Efficient purification of recombinant human tumor necrosis factor β from Escherichia coliyields biologically active protein with a trimeric structure that binds to both tumor necrosis factor receptors
J Biol Chem
1991
266
3863
3869
[PubMed]
20
Picarella
D
,
Kratz
A
,
Li
C-B
,
Ruddle
NH
,
Flavell
RA
Insulitis in transgenic mice expressing TNF-β (lymphotoxin) in the pancreas
Proc Natl Acad Sci USA
1992
89
10036
10040
[PubMed]
21
Hochman
PS
,
Majeau
GR
,
Mackay
F
,
Browning
JL
Proinflammatory responses are efficiently induced by homotrimeric but not heterotrimeric lymphotoxin ligands
J Inflamm
1996
46
220
234
[PubMed]
22
Browning
JL
,
Miatkowski
K
,
Sizing
I
,
Griffiths
D
,
Zafari
M
,
Benjamin
CD
,
Meier
W
,
Mackay
F
Signaling through the lymphotoxin β receptor induces the death of some adenocarcinoma tumor lines
J Exp Med
1996
183
867
878
[PubMed]
23
Degli-Esposti
MA
,
Davis-Smith
T
,
Din
WS
,
Smolak
PJ
,
Goodwin
RG
,
Smith
CA
Activation of the lymphotoxin β receptor by cross-linking induces chemokine production and growth arrest in A375 melanoma cells
J Immunol
1997
158
1756
1762
[PubMed]
24
De Togni
P
,
Goellner
J
,
Ruddle
NH
,
Streeter
PR
,
Fick
A
,
Mariathasan
S
,
Smith
SC
,
Carlson
R
,
Shornick
LP
,
Strauss-Schoenberger
J
et al
Abnormal development of peripheral lymphoid organs in mice deficient in lymphotoxin
Science
1994
264
703
707
[PubMed]
25
Banks
TA
,
Rouse
BT
,
Kerley
MK
,
Blair
PJ
,
Godfrey
VL
,
Kuklin
NA
,
Bouley
DM
,
Thomas
J
,
Kanangat
S
,
Mucenski
ML
Lymphotoxin-α–deficient mice: effects on secondary lymphoid organ development and humoral immune responsiveness
J Immunol
1995
155
1685
1693
[PubMed]
26
Matsumoto
M
,
Mariathasan
S
,
Nahm
MH
,
Baranyay
F
,
Peschon
JJ
,
Chaplin
DD
Role of lymphotoxin and the type I TNF receptor in the formation of germinal centers
Science
1996
271
1289
1291
[PubMed]
27
Matsumoto
M
,
Lo
SF
,
Carruthers
CJL
,
Min
J
,
Mariathasan
S
,
Huang
G
,
Plas
DR
,
Martin
SM
,
Geha
RS
,
Nahm
MH
,
Chaplin
DD
Affinity maturation without germinal centres in lymphotoxin-α–deficient mice
Nature
1996
382
462
466
[PubMed]
28
Koni
PA
,
Sacca
R
,
Lawton
P
,
Browning
JL
,
Ruddle
NH
,
Flavell
RA
Distinct roles in lymphoid organogenesis for lymphotoxins alpha α and β revealed in lymphotoxin β–deficient mice
Immunity
1997
6
491
500
[PubMed]
29
Peschon
JJ
,
Torrance
DS
,
Stocking
KL
,
Glaccum
MB
,
Otten
C
,
Willis
CR
,
Charrier
K
,
Morrissey
PJ
,
Ware
CB
,
Mohler
KM
TNF receptor–deficient mice reveal divergent roles for p55 and p75 in several models of inflammation
J Immunol
1998
160
943
952
[PubMed]
30
Hebel, R., and M.W. Stromberg. 1976. Anatomy of the Laboratory Rat. Williams & Wilkins Co., Baltimore. 112–118.
31
Rose
ML
,
Birbeck
MSC
,
Wallis
VJ
,
Forrester
JA
,
Davies
AJS
Peanut lectin binding properties of germinal centres of mouse lymphoid tissue
Nature
1980
284
364
366
[PubMed]
32
Kinoshita
T
,
Takeda
J
,
Hong
K
,
Kozono
H
,
Sakai
H
,
Inoue
K
Monoclonal antibodies to mouse complement receptor type 1 (CR1). Their use in a distribution study showing that mouse erythrocytes and platelets are CR1-negative
J Immunol
1988
140
3066
3072
[PubMed]
33
Fu
Y-X
,
Huang
G
,
Matsumoto
M
,
Molina
H
,
Chaplin
DD
Independent signals regulate development of primary and secondary follicle structure in spleen and mesenteric lymph node
Proc Natl Acad Sci USA
1997
94
5739
5743
[PubMed]
34
Alimzhanov
MB
,
Kuprash
DV
,
Kosco-Vilbois
MH
,
Luz
A
,
Turetskaya
RL
,
Tarakhovsky
A
,
Rajewski
K
,
Nedospasov
SA
,
Pfeffer
K
Abnormal development of secondary lymphoid tissues in lymphotoxin β–deficient mice
Proc Natl Acad Sci USA
1997
94
9302
9307
[PubMed]
35
Sacca
R
,
Cuff
CA
,
Lesslauer
W
,
Ruddle
NH
Differential activities of secreted lymphotoxin-α3 and membrane lymphotoxin-α1β2in lymphotoxin-induced inflammation: critical role of TNF receptor 1 signaling
J Immunol
1998
160
485
491
[PubMed]
36
Rennert
PD
,
Browning
JL
,
Mebius
R
,
MacKay
F
,
Hochman
PS
Surface lymphotoxin α/β complex is required for the development of peripheral lymphoid organs
J Exp Med
1996
184
1999
2006
[PubMed]
37
Neumann
B
,
Luz
A
,
Pfeffer
K
,
Holzmann
B
Defective Peyer's patch organogenesis in mice lacking the 55-kD receptor for tumor necrosis factor
J Exp Med
1996
184
259
264
[PubMed]
38
Pasparakis
M
,
Alexopoulou
L
,
Grell
M
,
Pfizenmaier
K
,
Bluethmann
H
,
Kollias
G
Peyer's patch organogenesis is intact yet formation of B lymphocyte follicles is defective in peripheral lymphoid organs of mice deficient for tumor necrosis factor and its 55-kDa receptor
Proc Natl Acad Sci USA
1997
94
6319
6323
[PubMed]
39
Mauri
DN
,
Ebner
R
,
Montgomery
RI
,
Kochel
KD
,
Cheung
TC
,
Yu
G-L
,
Ruben
S
,
Murphy
M
,
Eisenberg
RJ
,
Cohen
GH
et al
LIGHT, a new member of the TNF superfamily, and lymphotoxin α are ligands for herpesvirus entry mediator
Immunity
1998
8
21
30
[PubMed]
40
Nakano
H
,
Oshima
H
,
Chung
W
,
Williams-Abbott
L
,
Ware
CF
,
Yagita
H
,
Okumura
K
TRAF5, an activator of NF-κB and putative signal transducer for the lymphotoxin-β receptor
J Biol Chem
1996
271
14661
14664
[PubMed]
41
Force
W R
,
Cheung
TC
,
Ware
CF
Dominant negative mutants of TRAF3 reveal an important role for the coiled coil domains in cell death signaling by the lymphotoxin-β receptor
J Biol Chem
1997
272
30835
30840
[PubMed]
42
VanArsdale
TL
,
VanArsdale
SL
,
Force
WR
,
Walter
BN
,
Mosialos
G
,
Kieff
E
,
Reed
JC
,
Ware
CF
Lymphotoxin-β receptor signaling complex: role of tumor necrosis factor receptor–associated factor 3 recruitment in cell death and activation of nuclear factor κB
Proc Natl Acad Sci USA
1997
94
2460
2465
[PubMed]
43
Mackay
F
,
Majeau
GR
,
Hochman
PS
,
Browning
JL
Lymphotoxin β receptor triggering induces activation of the nuclear factor κB transcription factor in some cell types
J Biol Chem
1996
271
24934
24938
[PubMed]
44
Neutra
MR
,
Pringault
E
,
Kraehenbuhl
J-P
Antigen sampling across epithelial barriers and induction of mucosal immune responses
Annu Rev Immunol
1996
14
275
300
[PubMed]
45
Mowat
AM
,
Viney
JL
The anatomical basis of intestinal immunity
Immunol Rev
1997
156
145
166
[PubMed]
46
Mayrhofer
G
Peyer's patch organogenesis—cytokines rule, OK?
Gut
1997
41
707
709
[PubMed]

Author notes

Address correspondence to R.A. Flavell, Section of Immunobiology and Howard Hughes Medical Institute, Yale University School of Medicine, 310 Cedar Street, FMB 412, New Haven, CT 06520. Phone: 203-737-2216; Fax: 203-785-7561; E-mail: richard.flavell@qm.yale.edu